874 results on '"Waste-Water"'
Search Results
202. Cadmium adsorption on modified chitosan-coated bentonite: batch experimental studies.
- Author
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Arvand, Majid and Pakseresht, Mohammad A.
- Abstract
BACKGROUND: Several researchers have investigated the use of chitosan as an adsorbent for removal of heavy metals from aqueous streams. Chitosan flake or powder swells and crumbles making it unsuitable for use in an adsorption column. Chitosan also has a tendency to agglomerate or form a gel in aqueous media. The adsorption capacity can be enhanced by spreading chitosan on physical supports that can increase the accessibility of the metal binding sites. Although several attempts have been made to enhance the adsorption capacity of chitosan, using various chemicals, the sorption capacity for metal ions decreased after cross-linking of chitosan. RESULTS: Bentonite was coated with chitosan (Chi) and its derivative, 3,4-dimethoxy-benzaldehyde (Chi/DMB). The product was then used as adsorbent for the removal of Cd
2+ from aqueous solutions. The presence of imine groups resulting from chemical modification was confirmed using IR, DRS and SEM. The adsorption followed the Langmuir isotherm and could be described by pseudo-second order kinetics. CONCLUSION: Chi/DMB coated on bentonite increased the accessibility of metal binding sites. The Chi/DMB/bentonite showed no significant pH dependence in the pH range 2-9, but bentonite coated with chitosan revealed very intensive pH dependence, which had a considerable effect on cadmium removal. As expected adsorption of Cd2+ by Chi/bentonite and Chi/DMB/bentonite is dependent on contact time and adsorbent dose. In addition, an EDTA solution is suitable for desorption of cadmium ions, and the reusability of Chi/DMB/bentonite is quite good. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
203. The effect of an anti-depressant on responses to predation in an isopod
- Author
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Andrésen, Lisa and Andrésen, Lisa
- Abstract
A lot of chemicals and pharmaceutical substances used by humans, are released into the waste-water and end up in lakes and ponds. Further, because pharmaceutical substances are increasing worldwide, the problem increases. A very common human anti-depressant is fluoxetine which is found in lakes, ponds and even in the bodies of aquatic organisms. This study is focusing on how fluoxetine might change antipredation behaviour in the aquatic organism Asellus aquaticus. A. aquaticus live worldwide and are important for aquatic ecosystems because of its leaf litter decomposition degradation and hence nutrient cycling. A. aquaticus used in this study were wild-caught in lake Tåkern. In the lab, A. aquaticus were experimentally exposed to fluoxetine in an environmental relevant concentration, 20 ng/l, or kept in normal water as a control, for 28 days. After this exposure, A. aquaticus went through simulated predation attacks, and their responses were measured. I found no difference in anti-predation behaviour after the simulated predation attack in A. aquaticus, between the group exposed to fluoxetine and the control group. I found that males tended to be more active and explorative than females, but this was not affected by fluoxetine exposure. My results suggest that the dose of fluoxetine here used, did not cause behavioural changes as observed in other studies. Nevertheless, substance like fluoxetine are not the only pharmaceutical organisms in the wild are exposed to, and such cocktail effects may be additive. Future studies should therefore investigate how these substances both individually (in varying doses) and together, can affect aquatic organisms and ecosystems.
- Published
- 2019
204. Potential Benefits and Risks for Soil Health Derived From the Use of Organic Amendments in Agriculture
- Author
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Bioquímica y biología molecular, Derecho civil, Biokimika eta biologia molekularra, Zuzenbide zibila, Urra Ibañez de Sendadiano, Julen, Alcorta Calvo, Miren Itziar, Garbisu Crespo, Carlos, Bioquímica y biología molecular, Derecho civil, Biokimika eta biologia molekularra, Zuzenbide zibila, Urra Ibañez de Sendadiano, Julen, Alcorta Calvo, Miren Itziar, and Garbisu Crespo, Carlos
- Abstract
The use of organic amendments in agriculture is a common practice due to their potential to increase crop productivity and enhance soil health. Indeed, organic amendments of different origin and composition (e.g., animal slurry, manure, compost, sewage sludge, etc.) can supply valuable nutrients to the soil, as well as increase its organic matter content, with concomitant benefits for soil health. However, the application of organic amendments to agricultural soil entails a variety of risks for environmental and human health. Organic amendments often contain a range of pollutants, including heavy metals, persistent organic pollutants, potential human pathogens, and emerging pollutants. Regarding emerging pollutants, the presence of antibiotic residues, antibiotic-resistant bacteria, and antibiotic-resistance genes in agricultural amendments is currently a matter of much concern, due to the concomitant risks for human health. Similarly, currently, the introduction of microplastics to agricultural soil, via the application of organic amendments (mainly, sewage sludge), is a topic of much relevance, owing to its magnitude and potential adverse effects for environmental health. There is, currently, much interest in the development of efficient strategies to mitigate the risks associated to the application of organic amendments to agricultural soil, while benefiting from their numerous advantages.
- Published
- 2019
205. Silica based inorganic-organic hybrid materials for the adsorptive removal of chromium
- Author
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Duran, Hatice, Baig, H., Nayab, S., Ghaffar, A., Tuncel, E., Oluz, Zehra, Yameen, Basit, Duran, Hatice, Baig, H., Nayab, S., Ghaffar, A., Tuncel, E., Oluz, Zehra, and Yameen, Basit
- Abstract
We employed polymer functionalized silica gel as an adsorbent for the removal of Cr(vi) from water. The chains of 2-aminoethyl methacrylate hydrochloride (AEMA·HCl) polymer were grown from the surface of silica gel via surface-initiated conventional radical polymerization and the resulting hybrid material exhibited high affinity for chromium(vi). To investigate the adsorption behavior of Cr(vi) on diverse polymer based hybrid materials, the removal capacity of (SG-AEMH) was compared with our previously reported branched polyamine functionalized mesoporous silica (MS-PEI). The adsorption capacities of polymer based materials were also compared with their respective monolayer based platforms comprising a 3-aminopropyltriethoxysilane (APTES) functionalized silica gel (SG-APTES) and mesoporous silica (MS-APTES). The polymer based systems showed excellent Cr(vi) adsorption efficiencies compared to monolayer counterparts. The structural characteristics and surface modification of these adsorbents were examined by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The experimental data were analyzed using the Langmuir and Freundlich models. Correlation coefficients were determined by analyzing each isotherm. The kinetic data of adsorption reactions were described by pseudo-first-order and pseudo-second-order equations. Thermodynamic parameters, i.e., change in the free energy (?G°), the enthalpy (?H°), and the entropy (?S°), were also evaluated. The synthesized hybrid materials exhibited a high adsorption capacity for chromium ions. Furthermore, they could be regenerated and recycled effectively.
- Published
- 2019
206. From one species to another: A review on the interaction between chemistry and microbiology in relation to cleaning in the built environment
- Author
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Velazquez, Samantha, Griffiths, Willem, Dietz, Leslie, Horve, Patrick, Nunez, Susie, Hu, Jinglin, Shen, Jiaxian, Fretz, Mark, Bi, Chenyang, Xu, Ying, Van Den Wymelenberg, Kevin G., Hartmann, Erica M., Ishaq, Suzanne L., Velazquez, Samantha, Griffiths, Willem, Dietz, Leslie, Horve, Patrick, Nunez, Susie, Hu, Jinglin, Shen, Jiaxian, Fretz, Mark, Bi, Chenyang, Xu, Ying, Van Den Wymelenberg, Kevin G., Hartmann, Erica M., and Ishaq, Suzanne L.
- Abstract
Since the advent of soap, personal hygiene practices have revolved around removal, sterilization, and disinfection—both of visible soil and microscopic organisms—for a myriad of cultural, aesthetic, or health-related reasons. Cleaning methods and products vary widely in their recommended use, effectiveness, risk to users or building occupants, environmental sustainability, and ecological impact. Advancements in science and technology have facilitated in-depth analyses of the indoor microbiome, and studies in this field suggest that the traditional “scorched-earth cleaning” mentality—that surfaces must be completely sterilized and prevent microbial establishment—may contribute to long-term human health consequences. Moreover, the materials, products, activities, and microbial communities indoors all contribute to, or remove, chemical species to the indoor environment. This review examines the effects of cleaning with respect to the interaction of chemistry, indoor microbiology, and human health.
- Published
- 2019
207. Synthesis of peroxidase-encapsulated sodium cellulose sulphate/poly-dimethyl-diallyl-ammonium chloride biopolymer via polyelectrolyte complexation for enhanced removal of phenol
- Author
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Tung, Evelyn, Lau, John, Zeng, X., Danquah, M.K., Tung, Evelyn, Lau, John, Zeng, X., and Danquah, M.K.
- Abstract
Peroxidases have attracted significant interests in enzymatic wastewater treatment strategies. In this work, jicama peroxidase (JP) was extracted from jicama skin peels and used for the degradation of phenol under free and immobilized conditions. The crude enzyme extract demonstrated enzymatic activity of 1.6 ± 0.1 U mL−1. Sodium cellulose sulphate/poly-dimethyl-diallyl-ammonium chloride (NaCS-PDMDAAC) spherical capsules were synthesized and immobilized with crude JP to generate JP beaded capsules with an average diameter of 5.05 mm ± 0.16 mm. Phenol biodegradation analysis showed that the free and immobilized JP capsules demonstrated optimum working pH values of 7 and 6, respectively, and both systems maintained JP catalytic functionalities over a broad range of H2O2 concentration before H2O2 inhibition. The optimal temperature range for phenol removal was from 25°C to 40°C for both free and immobilized JP with lower removal efficiency above 45°C due to thermal denaturation. Due to diffusive mass transfer limitation, immobilized JP capsules required a longer reaction time of 15 hr for optimal phenol removal efficiency of >95%, whereas free JP achieved the same efficiency in 13 hr. The first order kinetic rate constants for free and immobilized JP capsules were determined to be 1.21 hr−1 and 1.02 hr−1, respectively. JP capsules maintained reusability up to 4 cycles at the highest removal efficiency of >95% with no regeneration.
- Published
- 2019
208. Mathematical modeling of biofilm-covered granular activated carbon: a review.
- Author
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Shen, Liang, Lu, Yinghua, and Liu, Yu
- Abstract
This paper reviewed the mass-transfer of the target substance in the biofilm-covered granular activated carbon (BGAC) system. Representative hypotheses and equations related to developing the mathematical models for a BGAC reactor were discussed in terms of granular activated carbon (GAC) phase, biofilm phase and bulk solution, respectively. It should be noted that discrete phenomena such as biofilm detachment due to erosion or sloughing were not considered for the modeling system. Recent advances on this topic were thoroughly updated, as well as those models proposed in past decades. It appears that a general BGAC model has not been available so far, and further efforts are required to obtain models more approaching of the physical mechanism of this complicate system. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
209. Waste-water impacts on groundwater: Cl/Br ratios and implications for arsenic pollution of groundwater in the Bengal Basin and Red River Basin, Vietnam
- Author
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McArthur, J.M., Sikdar, P.K., Hoque, M.A., and Ghosal, U.
- Subjects
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GROUNDWATER pollution , *ATMOSPHERIC models , *ARSENIC poisoning , *COMPOSITION of water , *DISSOLVED organic matter , *SEAWATER - Abstract
Abstract: Across West Bengal and Bangladesh, concentrations of Cl in much groundwater exceed the natural, upper limit of 10mg/L. The Cl/Br mass ratios in groundwaters range up to 2500 and scatter along mixing lines between waste-water and dilute groundwater, with many falling near the mean end-member value for waste-water of 1561 at 126mg/L Cl. Values of Cl/Br exceed the seawater ratio of 288 in uncommon NO3-bearing groundwaters, and in those containing measurable amounts of salt-corrected SO4 (SO4 corrected for marine salt). The data show that shallow groundwater tapped by tube-wells in the Bengal Basin has been widely contaminated by waste-water derived from pit latrines, septic tanks, and other methods of sanitary disposal, although reducing conditions in the aquifers have removed most evidence of NO3 additions from these sources, and much evidence of their additions of SO4. In groundwaters from wells in palaeo-channel settings, end-member modelling shows that >25% of wells yield water that comprises ≥10% of waste-water. In palaeo-interfluvial settings, only wells at the margins of the palaeo-interfluvial sequence contain detectable waste water. Settings are identifiable by well-colour survey, owner information, water composition, and drilling. Values of Cl/Br and faecal coliform counts are both inversely related to concentrations of pollutant As in groundwater, suggesting that waste-water contributions to groundwater in the near-field of septic-tanks and pit-latrines (within 30m) suppress the mechanism of As-pollution and lessen the prevalence and severity of As pollution. In the far-field of such sources, organic matter in waste-water may increase groundwater pollution by As. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
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210. Evaluation of a Bidisperse Pore Model for Ion Exchange Kinetics in Porous Media.
- Author
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Radulescu, M., Cox, M., and Oancea, A. M. S.
- Subjects
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WASTEWATER treatment , *ION exchange resins , *DIFFUSION , *PHASE transitions , *POROUS materials , *CHEMICAL kinetics , *MATHEMATICAL models - Abstract
A previously published bidisperse pore model that considers in turn ion interdiffusion in macro- and micro-pores as competitive and step-by-step processes was evaluated. The ion exchange rate of H+/Ni2+ on gel and macroporous strong acid resins was measured under conditions favoring a particle diffusion controlled mechanism. The interdiffusion coefficients were obtained using a bidisperse pore and quasi-homogenous resin phase kinetic models, respectively. The overall rate of H+/Ni2+ exchange on the macroporous resin is lower than in the gel resin. It was shown that ion interdiffusion in the micropores of the porous resin could also be important. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
211. SORPTION OF Pb(II) AND Cu(II) BY LOW-COST MAGNETIC EGGSHELLS-FE3O4 POWDER.
- Author
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Ren, Jianwei, Bopape, Mokgadi F., Setshedi, Katlego, Kitinya, Jacob O., and Onyango, Maurice S.
- Subjects
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SORPTION , *EGGSHELLS , *METAL powders , *MAGNETIC fields , *ADSORPTION (Chemistry) , *AQUEOUS solutions , *X-ray diffraction , *FOURIER transform infrared spectroscopy - Abstract
This study explored the feasibility ofusing magnetic eggshell-Fe3O4 powder as an adsorbent for the removal of Pb(II) and Cu(II) ions from aqueous solution. The metal ions-adsorption media interaction was characterized using XRD and FTIR. The effects of contact time, initial concentrations, temperature, solution pH and reusability ofthe adsorption media were investigated. The metal ions adsorption was fast and the amount of metal ions adsorbed increased with an increase in temperature, suggesting an endothermic adsorption. The kinetic data showed that the adsorption process followed the pseudo-second order kinetic model. The optimal adsorption pH value was around 5.5 at which con-dition the equilibrium capacity was 263.2 mg/g for Pb(II) and 250.0 mg/g for Cu(II). The adsorption equilibrium data fitted very well to the Langmuir and Freundlich adsorption isotherm models. The thermodynamics of Pb(II) and Cu(II) adsorption onto the magnetic eggshell-Fe3O4 powder indicated that the adsorption was spontaneous. The reusability study has proven that magnetic eggshell-Fe3O4 powder can be employed as a low-cost and easy to separate adsorbent. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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212. Sensitivity of spore germination and germ tube elongation of Saccharina japonica to metal exposure.
- Author
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Han, Taejun, Kong, Jeong-Ae, Kang, Hee-Gyu, Kim, Seon-Jin, Jin, Gyo-Sun, Choi, Hoon, and Brown, Murray
- Subjects
GERMINATION ,MARINE algae ,INDUSTRIAL wastes ,HEAVY metal toxicology ,TOXICITY testing - Abstract
The sensitivity of early life stages of the brown seaweed Saccharina japonica to six metals (Cd, Cu, Hg, Ni, Pb, Zn) and two waste-water samples were investigated and a new toxicity bioassay developed. The two endpoints used were spore germination and germ tube elongation with an exposure time of 24 h. Optimal test conditions determined for photon irradiance, pH, salinity and temperature were darkness, pH 8, 35‰ and 15°C, respectively. The toxicity ranking of five metals was: Hg (EC of 41 and 42 μg l) > Cu (120 and 81 μg l) > Ni (2,009 and 1,360 μg l) > Zn (3,024 and 3,897 μg l) > Pb (4,760 and 4,429 μg l) > Cd (15,052 and 7,541 μg l) for germination and germ tube elongation, respectively. The sensitivities to Cd, Cu and Ni were greater in germ tube elongation than in germination process. When tested against two different waste-water samples (processed animal and printed circuit board waste-water) values of EC were between 21.29 and 32.02% for germination and between 5.33 and 8.98% for germ tube elongation. Despite differences in their chemical composition, the toxic effects of waste-water samples, as indicated by EC values, did not differ significantly for the same endpoints. The CV range for both germination and germ tube elongation was between 4.61 and 37.69%, indicating high levels of precision of the tests. The results compare favourably with those from more established test procedures employing micro- and macroalgae. The advantages and potential limitations of the bioassay for the assessment of anthropogenic impacts on coastal ecosystems and commercial cultivation areas in near-shore environments are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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213. Surface engineered magnetic nanoparticles for removal of toxic metal ions and bacterial pathogens
- Author
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Singh, Sarika, Barick, K.C., and Bahadur, D.
- Subjects
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NANOPARTICLES , *SURFACES (Technology) , *METAL ions , *PATHOGENIC microorganisms , *X-ray diffraction , *TRANSMISSION electron microscopy , *IRON oxides , *SUCCINIC acid , *INDUSTRIAL wastes - Abstract
Abstract: Surface engineered magnetic nanoparticles (Fe3O4) were synthesized by facile soft-chemical approaches. XRD and TEM analyses reveal the formation of single-phase Fe3O4 inverse spinel nanostructures. The functionalization of Fe3O4 nanoparticles with carboxyl (succinic acid), amine (ethylenediamine) and thiol (2,3-dimercaptosuccinic acid) were evident from FTIR spectra, elemental analysis and zeta-potential measurements. From TEM micrographs, it has been observed that nanoparticles of average sizes about 10 and 6nm are formed in carboxyl and thiol functionalized Fe3O4, respectively. However, each amine functionalized Fe3O4 is of size ∼40nm comprising numerous nanoparticles of average diameter 6nm. These nanoparticles show superparamagnetic behavior at room temperature with strong field dependent magnetic responsivity. We have explored the efficiency of these nanoparticles for removal of toxic metal ions (Cr3+, Co2+, Ni2+, Cu2+, Cd2+, Pb2+ and As3+) and bacterial pathogens (Escherichia coli) from water. Depending upon the surface functionality (COOH, NH2 or SH), magnetic nanoadsorbents capture metal ions either by forming chelate complexes or ion exchange process or electrostatic interaction. It has been observed that the capture efficiency of bacteria is strongly dependent on the concentration of nanoadsorbents and their inoculation time. Furthermore, these nanoadsorbents can be used as highly efficient separable and reusable materials for removal of toxic metal ions. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
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214. Zeolite and fungi's flocculability of simulated wastewater containing heavy metal ions or phosphorus.
- Author
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CAO Wenchuan, HAO Jianchao, LIAN Bin, LIU Congqiang, and WU Fengchang
- Subjects
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ZEOLITES , *FUNGI , *HEAVY metals , *IONS , *PHOSPHORUS , *INDUSTRIAL wastes , *SOLUTION (Chemistry) - Abstract
This paper focuses on the flocculability of simulated wastewater containing heavy metal ions (Fe3+, Cd2+) or phosphorus by zeolite, microbial flocculants (MBF) produced by Aspergillus niger and the composite flocculant composed of zeolite and MBF. The main results are presented as follows: zeolite was a good flocculant when the contamination of the three simulated wastewaters was low, but the treated water is of turbidness and the particles in it are hard to precipitate. The MBF have a good flocculability toward Fe3+ wastewater, as well as particulate matter. Significant changes in flocculability occurred after adding the composite flocculant in different simulated wastewaters, the best or least effect respective for Fe3+ and Cd2+ wastewater. The research we have done shows that the method by which the composite flocculant is used to treat the wastewater containing heavy metal ions or phosphorus provides important reference value for practical application. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
215. Capillary electrophoresis and liquid chromatography for determining steroids in concentrates of purified water from Päijänne Lake
- Author
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Tuomas Tavaststjerna, Heli Sirén, Marja-Liisa Riekkola, Department of Chemistry, INAR Analytical Chemistry, and Helsinki Institute of Sustainability Science (HELSUS)
- Subjects
PHARMACEUTICALS ,DRINKING-WATER ,116 Chemical sciences ,Microemulsion electrokinetic capillary chromatography ,HEALTH-RISK ASSESSMENT ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Mass Spectrometry ,Micellar electrokinetic chromatography ,Analytical Chemistry ,chemistry.chemical_compound ,REMOVAL ,Capillary electrophoresis ,WASTE-WATER ,Tap water ,Limit of Detection ,Liquid chromatography–mass spectrometry ,SURFACE-WATER ,ENDOCRINE-DISRUPTING COMPOUNDS ,Solid phase extraction ,Liquid chromatography-mass spectrometry ,Gonadal Steroid Hormones ,1172 Environmental sciences ,Steroid hormones ,Detection limit ,Androsterone ,Chromatography ,Chemistry ,Solid Phase Extraction ,010401 analytical chemistry ,Organic Chemistry ,Electrophoresis, Capillary ,Water ,General Medicine ,Purified water ,6. Clean water ,0104 chemical sciences ,SOLID-PHASE EXTRACTION ,Lakes ,UHPLC-MS/MS ,HORMONES ,Steroids ,Partial filling micellar electrokinetic chromatography ,Water Pollutants, Chemical ,Chromatography, Liquid - Abstract
The research was done with partial filling micellar electrokinetic chromatography, microemulsion electrokinetic chromatography, and ultra-high performance liquid chromatography. The study focuses on determination of male and female steroids from cold and hot tap water of households in Helsinki City. The district ' s raw water is made run from Paijanne Lake through a water tunnel to the purification plants in Helsinki area. The effluents delivered from the plants to households as tap water were sampled and used for the study. They were concentrated with solid phase extraction to exceed the detection limits of the three methods. With partial filling method the limits were 0.50, 0.48, 0.33, and 0.50 mg/L for androsterone, testosterone, progesterone, and testosterone-glucuronide, respectively. In microemulsion method the limit values were 1.33, 1.11, and 0.40 mg/L for androsterone, testosterone, and progesterone, respectively, and 0.83, 0.45, and 0.50 mg/L for hydrocortisone, 17-alpha-hydroxyprogesterone, and 17-alpha-methyltestosterone, respectively. In the tap water samples, progesterone concentrations represented the highest values being 0.22 and 1.18 ng/L in cold and hot water, respectively. They also contained testosterone (in all samples), its glucuronide metabolite (in 25% of the samples), and androstenedione (in 75% of the samples). The ultra-high liquid chromatographic method with mass spectrometric detection was used for identification of the steroids at mu g/L level. (c) 2021 Elsevier B.V. All rights reserved.
- Published
- 2021
216. Kinetic studies on the potential use of citrus-based green and low-cost demulsifying agents for the oil-in-water emulsions' treatment.
- Author
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Moodley, Pia-Pritha, Lokhat, David, Ahmad, Akil, Mishra, Asmita, and Meikap, B.C.
- Subjects
LEMON ,EMULSIONS ,CITRUS fruits ,DEMULSIFICATION ,CITRIC acid ,EMULSIONS (Pharmacy) ,ORANGES - Abstract
Water and oil form stable emulsions that are difficult to separate without the proper resources. In this study, the performance of green and low-cost demulsification agents was assessed, and the influences of the operating parameters on the performance of the demulsification process were evaluated. The main objective was to examine the kinetics of each demulsification formula and the dehydration efficiency as a function of time. Citrus fruits, namely Citrus aurantifolia (lime) and Citrus limon (lemon), and ready to consume Citrus sinensis (orange) fruit juice was studied. Moreover, the rate constants (k), coefficient correlation (R
2 ), and the dehydration efficiencies (∅(t)) were analyzed for each PFO model. The first-order models could satisfactorily represent the experimental data for the orange, lime, and lemon demulsification agents. The lemon demulsification formulation worked best at a temperature of 80 °C. The optimal pH value for the formula was 5. The overall fit of the experimental data to the PFO model was satisfactory for the temperatures 60 °C, 70 °C, and 80 °C. However, variations in the pH of the treated solutions did not yield good first-order fits, presumably due to a change in the mechanism of demulsification. [Display omitted] • Low-cost demulsifying agent an effective method for oil-contaminated water remediation. • Experimental data fitted to pseudo-first-order kinetic model (PFO) model. • The best results for each demulsification formula were produced at 80 ℃. • Demulsification agents performed best at a pH of 5. • Best demulsification was obtained in Lemon for its high citric acid content (48 g/L). [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
217. Chemometrics assisted spectrophotometric determination of pyridine in water and wastewater
- Author
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Singh, Kunwar P., Basant, Nikita, Malik, Amrita, Singh, Vinod K., and Mohan, Dinesh
- Subjects
- *
DISSOLVED organic matter , *PYRIDINE , *SEWAGE , *SPECTROPHOTOMETRY , *CHEMOMETRICS , *ULTRAVIOLET spectrometry - Abstract
Abstract: The paper reports a direct method for the determination of pyridine in water and wastewater samples based on ultraviolet spectrophotometric measurements using multi-way modeling techniques. Parallel factor analysis (PARAFAC) and multi-way partial least squares (N-PLS) regression methods were employed for the decomposition of spectra and quantification of pyridine. The study was carried out in the pH range of 1.0–12.0 and concentration range of 0.67–51.7μgmL−1 of pyridine. Both the three-way PARAFAC and tri-PLS1 models successfully predicted the concentration of pyridine in synthetic (spiked) river water and field wastewater samples. The mean recovery obtained from PARAFAC regression model were 97.39% for the spiked and 99.84% for the field wastewater samples, respectively. The sensitivity and precision of the method for pyridine determination were 0.58% and 5.95%, respectively. The N-PLS regression model yielded mean recoveries of 99.29% and 100.18% for the spiked and field wastewater samples, respectively. The prediction accuracy of the methods was evaluated through the root mean square error of prediction (RMSEP). For PARAFAC, it was 0.65 and 0.82μgmL−1 for spiked river water and field wastewater samples, respectively, while for N-PLS, it was 0.25 and 0.37μgmL−1, respectively. Both the PARAFAC and N-PLS methods, thus, yielded satisfactory results for the prediction of pyridine concentration in water and wastewater samples. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
218. Identification and quantification of ibuprofen, naproxen, ketoprofen and diclofenac present in waste-waters, as their trimethylsilyl derivatives, by gas chromatography mass spectrometry
- Author
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Sebők, Á., Vasanits-Zsigrai, A., Palkó, Gy., Záray, Gy., and Molnár-Perl, I.
- Subjects
- *
NONSTEROIDAL anti-inflammatory agents , *NAPHTHALENEACETIC acid , *WATER quality management , *INTERMEDIATES (Chemistry) - Abstract
Abstract: This paper reports a derivatization, mass fragmentation study relating to the most common, non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, naproxen, ketoprofen and diclofenac, identified and quantified in the aquatic environment. Derivatizations have been performed with four silylation reagents in order to select the most proper one, taking into account analytical and financial points of view, equally. The tested reagents were N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA), N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide (MTBSTFA) and for this purpose at the first time, hexamethyldisilazan (HMDS)+trifluoroacetic acid (TFAA). Varying derivatization time and temperature, taking into consideration chemical and financial advantages, HMDS+TFAA proved to be the optimum selection. Responses of derivatives have been compared, as a function of the ionization technique (external/internal ionization), as well as on the treatment of compounds’ selective fragment ions (SFIs): (i) extracting the corresponding, characteristic m/z masses from TIC elutions and (ii) from SIM elutions, in parallel. Reproducibilities of measurements, expressed in relative standard deviation percentages (R.S.D.%), including the nanogram and the low picogram levels of injected derivatives, provided an average between 0.93 R.S.D.% and 4.11 R.S.D.%. NSAIDs’ enrichment was performed with solid-phase extraction (SPE), applying the Oasis HLB (Waters) cartridges: recoveries in the 1–6μgL−1 range varied between 84% and 111%, with an average reproducibility of 6.4 R.S.D.%. The utility of the optimized derivatization method is presented, on monthly basis, by the identification and quantitation of the ibuprofen, naproxen, ketoprofen and diclofenac content of the influent and effluent waste-water samples obtained from a Hungarian waste-water treatment plant. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
219. Performance Evaluation of Submerged Membrane Bioreactor Pilot Units for Refinery Wastewater Treatment.
- Author
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Torres, Ana Paula R., Santiago, Vânia M. J., and Borges, Cristiano P.
- Subjects
COMPARATIVE studies ,WASTEWATER treatment ,MEMBRANE reactors ,ARTIFICIAL membranes ,PETROLEUM refineries -- Equipment & supplies ,PETROLEUM refining & the environment ,SALINE water conversion ,INDUSTRIAL wastes ,WATER reuse - Abstract
The article presents the results of a comparative study involving membrane bioreactor (MBR) pilot units for potential use at a Petrobras SA petroleum refinery in Brazil. The design of the units is described, noting its submerged membrane configuration with microfiltration polymeric membranes, with one using a flat sheet membrane and the other using a hollow fiber membrane. The evaluation process of monitoring the biological and membrane process parameters is discussed. The results of the study are also analyzed, specifying that all MBR systems proved effective in pretreating petroleum industry effluent for the purposes of desalination for steam production or for reuse in the cooling tower system.
- Published
- 2008
220. Transcriptional and cellular effects of paracetamol in the oyster Crassostrea gigas
- Author
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Afonso Celso Dias Bainy, Rômi Sharon Piazza, Clei Endrigo Piazza, Flávia L. Zacchi, Miguel A. S. Serrano, Fabrício Flores-Nunes, Maria João Bebianno, Carlos Henrique A.M. Gomes, Cláudio Melo, Jacó Joaquim Mattos, Marília N. Siebert, and Álvaro C. P. Mello
- Subjects
Gills ,0301 basic medicine ,Oyster ,Hemocytes ,Antiinflammatory drugs nsaids ,Antioxidant ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Glutathione reductase ,010501 environmental sciences ,01 natural sciences ,Antioxidants ,chemistry.chemical_compound ,Fatty acid binding ,Clam ruditapes-philippinarum ,Biomarker approach ,biology ,General Medicine ,Pollution ,Pharmaceutical compounds ,Biochemistry ,Catalase ,Crassostrea ,Dreissena-polymorpha ,animal structures ,Cell Survival ,Superoxide dismutase ,03 medical and health sciences ,Environmental risk-assessment ,biology.animal ,medicine ,Animals ,Marine organisms ,Corbicula-fluminea ,Acetaminophen ,0105 earth and related environmental sciences ,Dose-Response Relationship, Drug ,fungi ,Mytilus-galloprovincialis ,Public Health, Environmental and Occupational Health ,Glutathione ,biology.organism_classification ,Oxidative Stress ,030104 developmental biology ,chemistry ,biology.protein ,Waste-water ,Transcriptome ,Water Pollutants, Chemical ,DNA Damage - Abstract
Acetaminophen (paracetamol) (PAR) is one of the most popular non-steroidal anti-inflammatory drugs (NSAIDs) with analgesic and antipyretic properties consumed worldwide and often detected in the aquatic environment. Due to the fact that PAR induces oxidative stress in mammals, the aim of this study was to evaluate if similar effects were observed in oysters Crassostrea gigas, given their economic and ecological importance and world-wide distribution. Oysters were exposed for 1, 4 and 7 days to two different sublethal PAR concentrations (0, 1 and 100 mu g L-1). Cell viability, DNA damage in hemocytes and enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferases (GST) were evaluated in oyster gills. In addition, changes at transcriptional level of Cu/Zn superoxide distnutase (SOD), catalase-like (CAT-like), cytochrome P450 genes (CYP30C1, CYP2AU2, CYP3071A1, CYP356A1), glutathione S-transferase isoforms (GST-omega and GST-pi-like), cyclooxygenase (COX), fatty acid binding proteins-like (FABP-like), and caspase genes were evaluated in oyster gills and digestive gland. No changes in cell viability and DNA damage were observed in oysters exposed to both PAR concentrations. Similarly, no significant changes were detected in the major antioxidant enzymes (except for auxiliary enzyme GR) in oyster gills, suggesting that changes in GR activity are enough to counteract a potential oxidative stress in C. gigas gills under these experimental conditions. Furthermore, changes at transcriptional level are concentration and tissue dependent. PAR elicited an inhibition of CYP30C1, CYP3071A1 and FABP-like transcripts highlighting their role in drug metabolism, transport and detoxification of PAR in the gills. GST transcript levels were type, tissue and concentration-dependent. GST-pi-like was down-regulated in oyster gills exposed to the lowest PAR concentration and up-regulated in the digestive gland of oysters exposed to the highest PAR concentration. However, GST-omega transcript levels were lower only in oysters digestive gland exposed to the lowest PAR concentration. Therefore, changes at transcriptional level were more sensitive to assess the exposure to PAR at environmental relevant concentrations. project UNIVERSAL - MCTI/CNPq [14/2012 (483028/21012-6)] MSC grant PEC-PG/CNPq CNPq [307467/2013-9] PVE-CNPq [406104/2013-1]
- Published
- 2017
221. Near-surface distributions of soil water and water repellency under three effluent irrigation schemes in a blue gum (Eucalyptus globulus) plantation
- Author
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Thwaites, L.A., de Rooij, G.H., Salzman, S., Allinson, G., Stagnitti, F., Carr, R., Versace, V., Struck, S., and March, T.
- Subjects
- *
SOIL moisture , *SEWAGE irrigation , *WATER reuse , *WATER in agriculture - Abstract
Abstract: Water repellent soils are difficult to irrigate and susceptible to preferential flow, which enhances the potential for accelerated leaching to groundwater of hazardous substances. Over 5Mha of Australian soil is water repellent, while treated municipal sewage is increasingly used for irrigation. Only if a critical water content is exceeded will repellent soils become wettable. To avoid excessive loss of water from the root zone via preferential flow paths, irrigation schemes should therefore aim to keep the soil wet enough to maintain soil wettability. Our objective was to monitor the near-surface water content and water repellency in a blue gum (Eucalyptus globulus) plantation irrigated with treated sewage. The plantation''s sandy soil surface was strongly water repellent when dry. For 4 months, three rows of 15 blue gum trees each received no irrigation, three other rows received 50% of the estimated potential water use minus rainfall, and three more rows received 100%. During this period, 162 soil samples were obtained in three sampling rounds, and their water content (% dry mass) and degree of water repellency determined. Both high and low irrigation effectively wetted up the soil and eliminated water repellency after 2 (high) or 4 (low) months. A single-peaked distribution of water contents was observed in the soil samples, but the water repellency distribution was dichotomous, with 44% extremely water-repellent and 36% wettable. This is consistent with a threshold water content at which a soil sample changes from water repellent to wettable, with spatial variability of this threshold creating a much wider transition zone at the field scale. We characterized this transition zone by expressing the fraction of wettable samples as a function of water content, and demonstrated a way to estimate from this the wettable portion of a field from a number of water content measurements. To keep the plantation soil wettable, the water content must be maintained at a level at which a significant downward flux is likely, with the associated enhanced leaching. At water contents with negligible downward flux, the field is water repellent, and leaching through preferential flow paths is likely. Careful management is needed to resolve these conflicting requirements. [Copyright &y& Elsevier]
- Published
- 2006
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222. Treatment and reuse of wastewater in pesticide 2,4-D production.
- Author
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Qiu, Y. P., Chen, J. L., Li, A. M., Chen, Y. L., and Zhang, Q. X.
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SEWAGE ,INDUSTRIAL wastes ,PESTICIDES ,POLLUTANTS ,ACIDIFICATION ,WASTE products ,CHEMICAL reactions ,ENVIRONMENTAL chemistry ,ANALYTICAL chemistry - Abstract
Waste-water from the production of pesticide 2,4-D often contains high concentrations of 2,4-DCP and 2,6-D as the primary pollutants. Treatment of waste-water collected from a 2,4-D manufacturer was carried out using a technology combining acidification with hyper-crosslinked resin NDA-150 adsorption process. The overall process recovered 5.4 kg of 2,4-DCP and 0.6 kg of 2,6-D per cubic metre of the wastewater. The treatment reduced the concentration of 2,4-DCP in the wastewater from >6000 mg/L to <0.5 mg/L. The optimal operation parameters of adsorption and desorption were determined. The hyper-crosslinked resin adsorbent can be re-used after regeneration by NaOH aqueous solution. The recovered 2,4-DCP with a sufficiently high purity may be re-used in the production of 2,4-D. The technology may thus be applied to the treatment of waste-water for reclamation of chemicals for 2,4-D production while minimising the environmental nuisances and hazards that may be caused by these chemicals. [ABSTRACT FROM AUTHOR]
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- 2006
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223. Electrochemical Detection of Atrazine by Platinum Nanoparticles/Carbon Nitride Nanotubes with Molecularly Imprinted Polymer
- Author
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Necip Atar, Mehmet Lütfi Yola, Mühendislik ve Doğa Bilimleri Fakültesi -- Biyomedikal Mühendisliği Bölümü, and Yola, Mehmet Lütfi
- Subjects
Water samples ,X ray photoelectron spectroscopy ,General Chemical Engineering ,Potentiometric sensor ,Analytical chemistry ,High resolution transmission electron microscopy ,02 engineering and technology ,Nitride ,Platinum nanoparticles ,01 natural sciences ,Industrial and Manufacturing Engineering ,Nanocomposites ,chemistry.chemical_compound ,Engineering ,Methyldopa | Levodopa | Carbon Electrodes ,Carbon nitride ,Platinum nano-particles ,Graphene oxide ,Nanotubes ,Quantum dots ,021001 nanoscience & nanotechnology ,Glass membrane electrodes ,0210 nano-technology ,Scanning electron microscopy ,Molecular imprinting polymer ,Glassy-carbon electrode ,Voltammetric sensor ,Materials science ,X ray diffraction ,Bismuth film electrode ,Chemical detection ,Chemical ,Energy dispersive x-ray analysis (EDX) ,010402 general chemistry ,Nitrides ,X-ray photoelectron spectroscopy ,Yarn ,Electron microscopy ,Electrochemical sensors ,High-resolution transmission electron microscopy ,Electrodes ,Platinum ,Solid-phase extraction ,Nanocomposite ,Herbicides ,Characterization studies ,Molecularly imprinted polymer ,Triazine herbicides ,ELectrochemical detection ,General Chemistry ,Methanol oxidation ,Molecularly Imprinted Polymer ,0104 chemical sciences ,Electrochemical gas sensor ,chemistry ,Glassy carbon electrodes ,Waste-water ,Transmission electron microscopy ,Nuclear chemistry - Abstract
WOS: 000405643200003, In this Article, a new electrochemical sensor based on molecular imprinting polymer (MIP) and platinum nanoparticles (Pt NPs)/carbon nitride nanotubes (C3N4 NTs) nanocomposite was developed for atrazine (ATR) analysis. First, the structures of prepared nanocomposites and surfaces were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). After the characterization studies, ATR-imprinted glassy carbon electrode (GCE) based on Pt NPs/C3N4 NTs nanocomposite was developed by 100 mM phenol containing 25 nM ATR: The linearity range and the detection limit of the molecular imprinted sensor were calculated as 1.0 X 10(-12)-1.0 X 10(-10) and 1.5 X 10(-13) M, respectively. In addition, the voltammetric sensor was applied to wastewater samples with high recovery.
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- 2017
224. Design of remediation pilot plants for the treatment of industrial metal-bearing effluents (BIOMETAL DEMO project): Lab tests
- Author
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Manuel Garcia-Roig, Maria Clara Costa, Eric Guibal, Jorge D. Carlier, Antonio Ballester, Angela Alvarez, Caroline Bertagnolli, Patricia Pérez-Galende, Laura Castro, Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Centro Multidisciplinar de Qu ́ımica do Ambiente, Departamento de Qu ́ımica e Bioqu ́ımica, Faculdade de Ciˆencias e Tecnologia,Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal, Universidad de Salamanca, CONTACTICA, Pôle Matériaux Polymères Avancés (Pôle MPA), Centre des Matériaux des Mines d'Alès (C2MA), IMT - MINES ALES (IMT - MINES ALES), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-IMT - MINES ALES (IMT - MINES ALES), and Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)
- Subjects
Metal bio-removal ,Equilibrium ,Environmental remediation ,Metal ions in aqueous solution ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,7. Clean energy ,Industrial and Manufacturing Engineering ,12. Responsible consumption ,[SPI]Engineering Sciences [physics] ,chemistry.chemical_compound ,Biological sulfate reduction ,Materials Chemistry ,media_common.cataloged_instance ,Sulfate-reducing bacteria ,Sulfate ,European union ,Integrated industrial wastewater treatment ,Effluent ,0105 earth and related environmental sciences ,media_common ,Ions ,Acid-mine drainage ,Metals and Alloys ,Biosorption ,Phytase ,021001 nanoscience & nanotechnology ,Pulp and paper industry ,Biometal ,chemistry ,Continuous Biosorption ,acid phosphatase ,Bio-precipitation ,Carbon source ,Waste-water ,Uranium ,0210 nano-technology ,Removal ,Alginate beads - Abstract
Current research is the first part of the BIOMETAL DEMO project, funded by the European Union, focusing on the development of complementary and modular biotreatment processes for the removal of metal ions from industrial effluents (issued from mining industry, surface treatment and ceramics). Metal bio-precipitation (in form of metal sulfides and metal phosphates) using sulfate-reducing bacteria (SRB), phytase and phosphatase enzymes, biosorption using sugar-beet pulp, algal biomass and alginate- or chitosan-based composites (immobilizing polyethyleneimine derivatives by encapsulation) have been extensively studied using synthetic and industrial effluents. These preliminary results allow designing a treatment flow-sheet including pre-treatment of the effluent using biologically-assisted precipitation followed by biosorption (for mining effluents that contain sulfate anions). For surface treatment and ceramics effluents, bio-precipitation combined with biosorption processes and physicochemical pretreatment followed by biosorption process represent, respectively, a promising solution. The carbon-source for the SRB process, the optimization of process parameters and the biosorbents have been selected taking into account both the technical performance and the economic viability. (C) 2016 Elsevier B.V. All rights reserved. European Union's Seventh Framework Programme (FP7) [619101] info:eu-repo/semantics/publishedVersion
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- 2017
225. A joint action of aptamers and gold nanoparticles chemically trapped on a glassy carbon support for the electrochemical sensing of ofloxacin
- Author
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Sandra Van Vlierberghe, Fabio Bottari, Beate Strehlitz, Els Vanderleyden, Christine Reinemann, Sanaz Pilehvar, Karolien De Wael, and Ronny Blust
- Subjects
Ofloxacin ,Materials science ,Aptamer ,Nanotechnology ,02 engineering and technology ,Glassy carbon ,Electrochemistry ,01 natural sciences ,Covalent attachment ,4-AMINOBENZOIC ACID ,WASTE-WATER ,AMPLIFIED DETECTION ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,Detection limit ,ELECTRODE ,SELECTIVE DETECTION ,010401 analytical chemistry ,Electrochemical aptasensor ,Metals and Alloys ,Environmental monitoring ,DNA ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,AU NANOPARTICLES ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Chemistry ,ULTRASENSITIVE DETECTION ,Water quality ,Physics and Astronomy ,Colloidal gold ,Covalent bond ,COLORIMETRIC APTASENSOR ,Electrode ,0210 nano-technology ,ANTIBIOTICS ,Biosensor - Abstract
A joint action of ssDNA aptamers and electrochemistry is a key element in developing successful biosensing platforms, since aptamers are capable of binding various targets with high specificity, and electrochemistry is one of the most sensitive techniques for on-site detections. A continuous search for improved immobilization and sensing strategies of aptamers on transducer surfaces resulted in the strategy presented in this article. The strategy is based on the covalent attachment of gold nanoparticles on the surface of glassy carbon electrodes through sulfhydryl-terminated monolayer, acting as a glue to connect AuNPs on the electrode. The covalently attached gold nanoparticles modified glassy carbon electrodes have been applied for the efficient immobilization of thiolated ssDNA probes, with a surface coverage of about 8.54 × 10 13 molecules cm −2 which was 7-fold higher than that on the electrochemically deposited gold nanoparticles. Consequently, improved sensitivity, good reproducibility and stability are achieved for electrochemical aptasensor. Combined with the high affinity and specificity of an aptamer, a simple, novel, rapid, sensitive and label-free electrochemical aptasensor was successfully fabricated for ofloxacin (OFL) detection. The linear dynamic range of the sensor varies between 5 × 10 −8 to 2 × 10 −5 M OFL with a detection limit of 1 × 10 −9 M OFL. A potential application in environmental monitoring was demonstrated by using this sensing strategy for the determination of OFL in (experimentally spiked) real samples such as tap water and effluent of sewage treatment plant. The proposed nanoaptasensor combines the advantages of the covalent attachment of neatly arranged AuNPs (enlarged active surface area and strengthened electrochemical signal) and the elimination of labels for the amplified detection of OFL, with the covalent attachment of highly specific aptamers to the surface of the modified electrode.
- Published
- 2017
226. The effect of TiO 2 nanoparticles removal on drinking water quality produced by conventional treatment C/F/S
- Author
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Claudia Corniciuc, Vânia Serrão Sousa, and Margarida Ribau Teixeira
- Subjects
Oxide nanoparticles ,Flocculation ,Environmental Engineering ,Ionic-strength ,Natural organic-matter ,Sedimentation (water treatment) ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Aggregation ,chemistry.chemical_compound ,Dissolved air flotation ,Coagulation (water treatment) ,Turbidity ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Water Science and Technology ,Civil and Structural Engineering ,Titanium-dioxide nanoparticles ,Coagulation ,Cyanobacterial cells ,Chemistry ,Ecological Modeling ,technology, industry, and agriculture ,Environmental engineering ,Contamination ,021001 nanoscience & nanotechnology ,Pollution ,Environmental chemistry ,Titanium dioxide ,Waste-water ,Water treatment ,Water quality ,Silver nanoparticles ,0210 nano-technology - Abstract
Nanoparticles, namely titanium dioxide (TiO2), are emerging contaminants widely used to commercial and industrial applications, are a potential hazard and can cause damage to environment and human health due to their toxicity. Therefore, their removal from the water is urgent to minimize or eliminate the adverse environmental and human effects. This work, investigates the efficiency of conventional coagulation/flocculation/sedimentation (C/F/S) from drinking water treatment to remove TiO2 nano particles (NPs) from surface waters, and pretends to understand if the removal of TiO2 NPs affects the ability of C/F/S to remove natural organic matter (NOM) and turbidity, and consequently affects the quality of the treated water. Results show that TiO2 NPs removal is high (>90%) for all the waters studied (hydrophobic and hydrophilic waters) and the treated water quality is not compromised (turbidity, Ti and Al concentrations, pH and conductivity are below the national and international guidelines). In addition, TiO2 initial concentrations, ranging between 0.2 and 10 mg/L, have not a significant impact on NPs removal by C/F/S. Therefore, the widely used polyaluminium based coagulants are effective in the removal of TiO2 NPs by conventional C/F/S treatment, but removal is strongly influenced by the water characteristics. Hydrophobic waters need a higher coagulant dose than hydrophilic waters to achieve the same TiO2 NPs removals, as well as water with higher UV254nm values. The principal mechanism involved in TiO2 NPs removal is charge neutralisation. (C) 2016 Elsevier Ltd. All rights reserved. Portuguese Foundation of Science and Technology [SFRH/BD/100402/2014]
- Published
- 2017
227. A Strategic Framework for Managing Wastewater A Case Study of Harare, Zimbabwe.
- Author
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Nhapi, Innocent, Siebel, Maarten A., and Gijzen, Huub J.
- Subjects
- *
WATER quality management , *WATER conservation , *WATER supply , *CASE studies , *INDUSTRIAL wastes , *WATER use , *WATER purification - Abstract
Water quality is an urgent problem in Harare's main water supply source, Lake Chivero, while water scarcity will be a problem soon. This study focuses on sustainable ways of urban water and nutrient (nitrogen and phosphorus) management in Harare, part of the Lake Chivero catchment. The Dublin Principles on water conservation, environmental protection, reuse, and economic utilization of water were used as a basis for formulating innovative and responsive solutions. External and internal drivers for future evolution of wastewater approaches are identified. Water conservation, treatment, and reuse strategies are developed including water-saving devices, regulation, leak detection and repair and including wastewater treatment and reuse. The three levels where wastewater can be handled – onsite, decentralized, and centralized – are discussed and solutions formulated. Based on this, a strategic framework, the so-called "3-Step Strategic Approach," is then developed aimed at the sustainable use of water nutrients, and other resources in the urban environment. This 3-Step Strategic Approach consists of pollution prevention and minimization (Step 1), reuse after treatment (Step 2), and discharge into the environment with stimulation of self-purification capacity of the receiving environment (Step 3). The 3-Step Strategic Approach was subsequently applied to the Lake Chivero catchment, which demonstrated that these strategies could substantially reduce current water pollution and future water scarcity problems in Harare. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
228. Oxidación fotocatalítica de aguas residuales de la industria de lavandería utilizando TiO2 como catalizador y luz UV.
- Author
-
Pavas, Edison Gil
- Subjects
- *
PHOTODEGRADATION , *PHOTOCATALYTIC water purification , *BIOENGINEERING , *CATALYSTS , *LAUNDRY industry , *ENVIRONMENTAL degradation , *WATER purification chemicals industry - Abstract
The catalytic photodegradation of the waste water of the laundry industry in a Parabolic Composite Cylinder (PCC) photo-reactor is studied in this work. The technology of photocatalysis was used with artificial sources of radiation (lamps UV) and TiO2 as catalyst. The study was with Industrial waste water with the objective to begin to carry out an investigation with real liquid effluents and not with prepared synthetic mixtures in the laboratory, since what it looks for with this project it is to take a first step towards the use of these new technologies on industrial scale. The experimental results were process statistically by model of response surface. The concentration of catalyst, pH and the recirculation time were the parameters that affected the final concentration of COD, variable of response. The degradation obtained was 26.49% without H2O2 and 41.8%. with addition of H2O2. [ABSTRACT FROM AUTHOR]
- Published
- 2005
229. THE Loads of PAHs in Wastewater and Sewage Sludge of Municipal Treatment Plant.
- Author
-
Wlodarczyk-Makula, Maria
- Subjects
- *
POLYCYCLIC aromatic hydrocarbons , *POLYCYCLIC aromatic compounds , *INDUSTRIAL wastes , *SEWAGE , *ORGANIC wastes - Abstract
Sewage and sewage sludge from a municipal wastewater treatment plant were analyzed for 16 EPA-PAHs. This plant is a classic mechanical-biological treatment plant, consisting of activated sludge technology with additional chemical treatment for the removal of phosphorus compounds. The process of sewage sludge treatment is carried out in closed as well as open sludge digesters. Primary and mechanically thickened sludge are passed through the fermentation process. Digested sludge is dewatered on filter-press through addition of flocculent. The measurements were obtained to investigate the effect of different treatment stages on PAH content in wastewater and sewage sludge. The following wastewater samples were collected: crude ones and those after sand trap, primary sedimentation, biological treatment and secondary sedimentation. Sewage sludge samples were collected from: primary sludge, digested sludge and dewatered sludge. PAH load in influent, mechanically and biologically treated sewage, as well as in raw digested and dewatered sludge, were calculated. PAHs were extracted from wastewater and sludge samples, with cyclohexane, dichloromethane using an ultrasonic method. Gas chromatograph equipped with mass spectrometry was used for qualitative and quantitative determination of PAHs. Mechanical and biological treatment proved the removal of 83–85% of PAHs from the influent. Despite this its daily PAH load introduced into the environment was high and reached 27–37% of PAH load in influent. In sewage sludge it was 46–70 g/d of PAHs (carcinogenic PAHs content 4–12%). In waste sludge (filter pressed sludge and sand from detrirer) PAH total load reached 42–68 g/d with (10–17% of carcinogenic PAHs). [ABSTRACT FROM AUTHOR]
- Published
- 2005
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230. Quantitative and qualitative hydrologic balance for a suburban watershed with a separate sewer system (Nantes, France).
- Author
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Ruban, V., Larrarte, F., Berthier, M., Favreau, L., Sauvourel, Y., Letellier, L., Mosisni, M.-L., and Raimbault, G.
- Subjects
- *
HYDROLOGIC cycle , *RUNOFF , *STORM drains , *WATER pollution , *PESTICIDE pollution - Abstract
A qualitative and quantitative budget at the outlet of the storm-water runoff system of a small suburban watershed is presented together with some data regarding waste-water. 445,000 m³ (34% of the rain-water volume) were drained by the storm-water runoff system and 40,879 m³ by the waste-water system from September 2002 to March 2004. Storm-water runoff is generally not heavily polluted with regard to trace metals but concentrations occasionally exceed the standards for surface water of good quality. On the contrary, pesticides (diuron and glyphosate) have very high concentrations especially in spring and autumn when their use is maximum. As the St Joseph storm-water runoff is finally discharged into the Erdre River, measures to reduce the use of these pollutants should be considered. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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231. Synthesis of nanophase hydroxyapatite by aSerratiasp. from waste-water containing inorganic phosphate.
- Author
-
Yong, P., Macaskie, L. E., Sammons, R. l., and Marquis, P. M.
- Subjects
HYDROXYAPATITE ,NUCLEATION ,APATITE ,CALCIUM phosphate ,SCANNING electron microscopy ,CRYSTALS - Abstract
Synthesis of nanophase hydroxyapatite (HA) on a bacterial surface was achieved at the expense of CaCl
2 and inorganic phosphate (Pi). After initial nucleation, calcium was precipitated on and around the cells as calcium phosphate at the expense of inorganic phosphate in the challenge solution, with no precipitation in cell-free controls. HA was also biomanufactured using inorganic phosphate ions scavenged from a phosphate-containing waste-water. With additional Ca2+ , the concentration of phosphate was decreased from 0.27 (~25?ppm) to ~0.02mM(~2?ppm) in the waste-water. Crystals of calcium phosphate manufactured by the cells were located by scanning electron microscopy (SEM) and identified as HA by X-ray powder diffraction, with an average crystal size calculated as ~25?nm. Possible application of bioHA as a biomaterial and implications for one-step ‘waste-into product’ are discussed. [ABSTRACT FROM AUTHOR]- Published
- 2004
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232. Simulation der aeroben und anaeroben Abwasserreinigung mit einfachen Mitteln.
- Author
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Baumann, Urs, Peter, Gustav, Pletscher, Ernst, and Wettstein, Marcel
- Abstract
Copyright of Umweltwissenschaften und Schadstoff-Forschung is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2003
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- View/download PDF
233. Enhancement of C-phycocyanin productivity by Arthrospira platensis when growing on palm oil mill effluent in a two-stage semi-continuous cultivation mode
- Author
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M. M. Azimatun Nur, Anita G. J. Buma, Peter Boelen, G. M. Garcia, and Ocean Ecosystems
- Subjects
0106 biological sciences ,EXTRACTION ,Arthrospira platensis ,Biomass ,chemistry.chemical_element ,Plant Science ,Aquatic Science ,Wastewater ,01 natural sciences ,BIOMASS ,MICROALGAE ,semi-continuous ,REMOVAL ,Pome ,WASTE-WATER ,ANTIOXIDANT ,Urea ,Response surface methodology ,LIPID PRODUCTION ,OPTIMIZATION ,Light intensity ,010604 marine biology & hydrobiology ,Phosphorus ,Pulp and paper industry ,SPIRULINA-PLATENSIS ,Salinity ,chemistry ,Productivity (ecology) ,C-PC ,Environmental science ,GROWTH ,010606 plant biology & botany - Abstract
Palm oil mill effluent (POME) is well known as agricultural wastewater that has a high potential as a medium for microalgal growth due to its high macro- and micronutrient content. The cyanobacterium Arthrospira platensis is considered as a species with a high C-phycocyanin (C-PC) content which is important for fine chemical and pharmaceutical applications. However, cultivation of A. platensis on POME to produce economically feasible amounts of C-PC has not been well explored. For this, environmental, nutritional, and cultivation modes (batch, semi-continuous) were varied to optimize C-PC productivity when cultivated at various POME concentrations. Arthrospira platensis was found to grow well on POME. Highest biomass and C-PC concentrations were found on 30–100% POME. Central composite rotatable design (CCRD) response surface methodology demonstrated that C-PC productivity was influenced by urea addition at the optimum salinity. The highest C-PC productivity was found on 100% POME during semi-continuous cultivation, while the addition of phosphorus and urea did not significantly improve C-PC productivity. By applying semi-continuous cultivation with 50% POME at the first stage and 100% POME at the second stage, a similarly high C-PC productivity (4.08 ± 1.3 mg L−1 day−1) was achieved as compared with (artificial) Zarrouk medium during batch cultivation. We conclude that, when using a two-stage semi-continuous cultivation process, A. platensis can produce economically feasible amounts of C-PC when cultivated on 100% POME.
- Published
- 2019
234. Biochemical properties of a Pseudomonas aminotransferase involved in caprolactam metabolism
- Author
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Henriëtte J. Rozeboom, Marleen Otzen, Elisa Lanfranchi, Dick B. Janssen, Cyntia M. Palacio, Qinglong Meng, and Biotechnology
- Subjects
0301 basic medicine ,Specificity constant ,Models, Molecular ,OMEGA-AMINOTRANSFERASE ,Stereochemistry ,substrate specificity ,Pseudomonas jessenii ,Sequence Homology ,Crystallography, X-Ray ,Biochemistry ,Cofactor ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,nylon 6 ,Bacterial Proteins ,WASTE-WATER ,Pseudomonas ,Transferase ,Caprolactam ,CRYSTAL-STRUCTURES ,Enzyme kinetics ,Amino Acid Sequence ,Pyridoxal phosphate ,protein structure ,ASYMMETRIC-SYNTHESIS ,Molecular Biology ,Phylogeny ,Transaminases ,pyridoxal phosphate ,biology ,ACTIVE-SITE ,aminotransferase ,AMINE-PYRUVATE TRANSAMINASE ,Active site ,Cell Biology ,VIBRIO-FLUVIALIS ,biology.organism_classification ,SUBSTRATE-SPECIFICITY ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Aminocaproic Acid ,biology.protein ,6-aminohexanoic acid ,KINETIC RESOLUTION ,LYSINE EPSILON-AMINOTRANSFERASE ,deamination - Abstract
The biodegradation of the nylon-6 precursor caprolactam by a strain of Pseudomonas jessenii proceeds via ATP-dependent hydrolytic ring-opening to 6-aminohexanoate. This non-natural ω-amino acid is converted to 6-oxohexanoic acid by an aminotransferase (PjAT) belonging to the fold type I PLP enzymes. To understand the structural basis of 6-aminohexanoatate conversion, we solved different crystal structures and determined the substrate scope with a range of aliphatic and aromatic amines. Comparison with the homologous aminotransferases from Chromobacterium violaceum (CvAT) and Vibrio fluvialis (VfAT) showed that the PjAT enzyme has the lowest KM values (highest affinity) and highest specificity constant (kcat /KM ) with the caprolactam degradation intermediates 6-aminohexanoate and 6-oxohexanoic acid, in accordance with its proposed in vivo function. Five distinct three-dimensional structures of PjAT were solved by protein crystallography. The structure of the aldimine intermediate formed from 6-aminohexanoate and the PLP cofactor revealed the presence of a narrow hydrophobic substrate-binding tunnel leading to the cofactor and covered by a flexible arginine, which explains the high activity and selectivity of the PjAT with 6-aminohexanoate. The results suggest that the degradation pathway for caprolactam has recruited an aminotransferase that is well adapted to 6-aminohexanoate degradation. This article is protected by copyright. All rights reserved.
- Published
- 2019
235. Agricultural land-uses consistently exacerbate infectious disease risks in Southeast Asia
- Author
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Hiral A Shah, Jocelyn Elmes, Kris A. Murray, Paul Huxley, and Medical Research Council (MRC)
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Databases, Factual ,Epidemiology ,General Physics and Astronomy ,ECOSYSTEM SERVICES ,Scrub typhus ,Disease ,0302 clinical medicine ,Agricultural land ,HUMAN-POPULATIONS ,030212 general & internal medicine ,lcsh:Science ,HELMINTH INFECTIONS ,Asia, Southeastern ,2. Zero hunger ,Tick-borne disease ,CLIMATE-CHANGE ,Multidisciplinary ,Agriculture ,FOREST FRAGMENTATION ,3. Good health ,Multidisciplinary Sciences ,Geography ,Infectious diseases ,Science & Technology - Other Topics ,Science ,030231 tropical medicine ,Communicable Diseases ,Article ,General Biochemistry, Genetics and Molecular Biology ,PARTICIPATORY EPIDEMIOLOGY ,03 medical and health sciences ,WASTE-WATER ,Environmental health ,medicine ,Animals ,Humans ,JAPANESE ENCEPHALITIS ,Ecosystem ,Ecological epidemiology ,Science & Technology ,business.industry ,LYME-DISEASE ,General Chemistry ,15. Life on land ,medicine.disease ,Spotted fever ,Risk factors ,Infectious disease (medical specialty) ,TICK-BORNE DISEASES ,lcsh:Q ,business ,Malaria - Abstract
Agriculture has been implicated as a potential driver of human infectious diseases. However, the generality of disease-agriculture relationships has not been systematically assessed, hindering efforts to incorporate human health considerations into land-use and development policies. Here we perform a meta-analysis with 34 eligible studies and show that people who live or work in agricultural land in Southeast Asia are on average 1.74 (CI 1.47–2.07) times as likely to be infected with a pathogen than those unexposed. Effect sizes are greatest for exposure to oil palm, rubber, and non-poultry based livestock farming and for hookworm (OR 2.42, CI 1.56–3.75), malaria (OR 2.00, CI 1.46–2.73), scrub typhus (OR 2.37, CI 1.41–3.96) and spotted fever group diseases (OR 3.91, CI 2.61–5.85). In contrast, no change in infection risk is detected for faecal-oral route diseases. Although responses vary by land-use and disease types, results suggest that agricultural land-uses exacerbate many infectious diseases in Southeast Asia., Here, Shah et al. perform a meta-analysis and show that people who live or work in agricultural land in Southeast Asia are on average 1.7 times more likely to be infected with a pathogen than controls, suggesting that agricultural land-use increases infectious disease risk.
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- 2019
236. Indoor Air
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Velazquez, Samantha, Griffiths, Willem, Dietz, Leslie, Horve, Patrick, Nunez, Susie, Hu, Jinglin, Shen, Jiaxian, Fretz, Mark, Bi, Chenyang, Xu, Ying, Van Den Wymelenberg, Kevin G., Hartmann, Erica M., and Ishaq, Suzanne L.
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CONSUMER PRODUCTS ,ENDOCRINE-DISRUPTING CHEMICALS ,04 Earth Sciences ,chemical intervention ,VOLATILE ORGANIC-COMPOUNDS ,09 Engineering ,SODIUM-HYPOCHLORITE ,Engineering ,HYDROGEN-PEROXIDE ,WASTE-WATER ,Humans ,indoor microbiology ,Built Environment ,urface chemistry ,11 Medical and Health Sciences ,Public, Environmental & Occupational Health ,STAPHYLOCOCCUS-AUREUS ,Building & Construction ,INDOOR AIR ,ANTIBIOTIC-RESISTANCE GENES ,SURFACES ,Microbiota ,Engineering, Environmental ,surface microbiology ,Disinfection ,occupant health ,Air Pollution, Indoor ,Construction & Building Technology ,Life Sciences & Biomedicine ,antimicrobial resistance genes - Abstract
Since the advent of soap, personal hygiene practices have revolved around removal, sterilization, and disinfection—both of visible soil and microscopic organisms—for a myriad of cultural, aesthetic, or health-related reasons. Cleaning methods and products vary widely in their recommended use, effectiveness, risk to users or building occupants, environmental sustainability, and ecological impact. Advancements in science and technology have facilitated in-depth analyses of the indoor microbiome, and studies in this field suggest that the traditional “scorched-earth cleaning” mentality—that surfaces must be completely sterilized and prevent microbial establishment—may contribute to long-term human health consequences. Moreover, the materials, products, activities, and microbial communities indoors all contribute to, or remove, chemical species to the indoor environment. This review examines the effects of cleaning with respect to the interaction of chemistry, indoor microbiology, and human health. Published version
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- 2019
237. Potential Benefits and Risks for Soil Health Derived From the Use of Organic Amendments in Agriculture
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Carlos Garbisu, Itziar Alkorta, and Julen Urra
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sewage-sludge ,waste-water ,antibiotic resistance ,bacterial community structure ,tetracycline resistance ,state anaerobic-digestion ,long-term application ,010501 environmental sciences ,engineering.material ,01 natural sciences ,complex mixtures ,lcsh:Agriculture ,Environmental protection ,Organic matter ,0105 earth and related environmental sciences ,Soil health ,Pollutant ,Sewage sludge ,chemistry.chemical_classification ,soil health ,Compost ,business.industry ,sustainable intensification ,antibiotic-resistance genes ,fungi ,lcsh:S ,food and beverages ,soil conservation ,04 agricultural and veterinary sciences ,food security ,Manure ,chemistry ,Agriculture ,water treatment plants ,040103 agronomy & agriculture ,engineering ,0401 agriculture, forestry, and fisheries ,Environmental science ,microbial community ,business ,Soil conservation ,ecosystem services ,Agronomy and Crop Science ,agricultural systems - Abstract
The use of organic amendments in agriculture is a common practice due to their potential to increase crop productivity and enhance soil health. Indeed, organic amendments of different origin and composition (e.g., animal slurry, manure, compost, sewage sludge, etc.) can supply valuable nutrients to the soil, as well as increase its organic matter content, with concomitant benefits for soil health. However, the application of organic amendments to agricultural soil entails a variety of risks for environmental and human health. Organic amendments often contain a range of pollutants, including heavy metals, persistent organic pollutants, potential human pathogens, and emerging pollutants. Regarding emerging pollutants, the presence of antibiotic residues, antibiotic-resistant bacteria, and antibiotic-resistance genes in agricultural amendments is currently a matter of much concern, due to the concomitant risks for human health. Similarly, currently, the introduction of microplastics to agricultural soil, via the application of organic amendments (mainly, sewage sludge), is a topic of much relevance, owing to its magnitude and potential adverse effects for environmental health. There is, currently, much interest in the development of efficient strategies to mitigate the risks associated to the application of organic amendments to agricultural soil, while benefiting from their numerous advantages. J.U. was the recipient of a predoctoral fellowship from the Department for Economic Development and Infrastructures of the Basque Government
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- 2019
238. Ab initio screening of cation-exchanged zeolites for biofuel purification
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Hicham Jabraoui, Ibrahim Khalil, Sébastien Lebègue, and Michael Badawi
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Technology ,Engineering, Chemical ,ADSORPTION ,Inorganic chemistry ,Materials Science ,Biomedical Engineering ,Energy Engineering and Power Technology ,Materials Science, Multidisciplinary ,engineering.material ,Fluid catalytic cracking ,Industrial and Manufacturing Engineering ,DENSITY-FUNCTIONAL THEORY ,chemistry.chemical_compound ,METAL-ORGANIC FRAMEWORKS ,Adsorption ,Engineering ,WASTE-WATER ,Materials Chemistry ,Chemical Engineering (miscellaneous) ,Phenol ,FAUJASITE ZEOLITES ,Lewis acids and bases ,Nanoscience & Nanotechnology ,Zeolite ,Science & Technology ,Chemistry ,Chemistry, Physical ,Process Chemistry and Technology ,Interaction energy ,Faujasite ,Toluene ,CO ,Chemistry (miscellaneous) ,MOLECULAR-DYNAMICS ,PHENOL ,Physical Sciences ,engineering ,Science & Technology - Other Topics ,ACTIVE-SITES ,NAY - Abstract
Using periodic density functional theory calculations combined with four dispersion-correction schemes, we have investigated the adsorption of phenol, toluene and water for various cation-exchanged faujasite zeolites. In the context of purifying the biofuels derived from the catalytic cracking of lignocellulosic bio-oils in a fluid catalytic cracking (FCC) unit, our aim was to find a suitable material with a higher affinity for phenol versus toluene and water, which are also present in the biofuel charge. In order to identify the most promising adsorbent materials, we have undertaken a full screening of monovalent cations which can be incorporated into the faujasite-type zeolite (FAU). We have evidenced that phenol can be adsorbed in two modes: O-interaction (where phenol is adsorbed via its oxygen) and π-interaction (where phenol is adsorbed via its aromatic ring). The screening of the interaction energies of the different exchanged zeolites showed that over HFAU the phenol is selectively adsorbed via O-interaction, contrary to what is observed over alkali and transition metal exchanged zeolites where the π-interaction dominates for the adsorption of phenol, leading to weaker interaction with the zeolite compared to toluene. On the Lewis modeled acid sites, namely the defect Lewis acid site (D-LAS) and the extraframework Lewis acid site (EX-LAS), the two interaction modes of phenol show almost equivalent interaction energies. In terms of selectivity, HFAU is the most selective to phenol adsorption towards O-interaction even in the presence of toluene and H2O molecules. Both adsorption modes of phenol present a higher interaction energy than those of toluene and H2O once adsorbed over an EX-LAS. The alkali and metallic cations have a high affinity for toluene molecules, which prohibit their use for the biofuel purification process.
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- 2019
239. Conversion of Chitin to Defined Chitosan Oligomers
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deacetylation ,CHITOOLIGOSACCHARIDES ,enzymatic conversion ,BIOLOGICAL-ACTIVITIES ,chitosan oligomers ,chitin ,design of experiments ,ENZYME COCKTAILS ,MOLECULAR-WEIGHT ,WASTE-WATER ,ESCHERICHIA-COLI ,MUCOR-ROUXII ,depolymerization ,SHRIMP BY-PRODUCTS ,ANTIFUNGAL CHITINASE ,chitosan ,DEACETYLASE - Abstract
Chitin is an abundant polysaccharide primarily produced as an industrial waste stream during the processing of crustaceans. Despite the limited applications of chitin, there is interest from the medical, agrochemical, food and cosmetic industries because it can be converted into chitosan and partially acetylated chitosan oligomers (COS). These molecules have various useful properties, including antimicrobial and anti-inflammatory activities. The chemical production of COS is environmentally hazardous and it is difficult to control the degree of polymerization and acetylation. These issues can be addressed by using specific enzymes, particularly chitinases, chitosanases and chitin deacetylases, which yield better-defined chitosan and COS mixtures. In this review, we summarize recent chemical and enzymatic approaches for the production of chitosan and COS. We also discuss a design-of-experiments approach for process optimization that could help to enhance enzymatic processes in terms of product yield and product characteristics. This may allow the production of novel COS structures with unique functional properties to further expand the applications of these diverse bioactive molecules.
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- 2019
240. Selective extraction of aliphatic amines by functionalized mesoporous silica-coated solid phase microextraction Arrow
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Hangzhen Lan, Risto Koivula, Wenzhong Zhang, Kari Hartonen, Marja-Liisa Riekkola, Jan-Henrik Smått, Department of Chemistry, Institute for Atmospheric and Earth System Research (INAR), and Ion exchange for nuclear waste treatment and for recycling
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ADSORPTION ,010504 meteorology & atmospheric sciences ,SAMPLES ,116 Chemical sciences ,Urine ,Solid-phase microextraction ,01 natural sciences ,BIOMASS ,Analytical Chemistry ,Mushroom ,METAL-ORGANIC FRAMEWORKS ,Solid phase microextraction Arrow ,chemistry.chemical_compound ,WASTE-WATER ,Selective extraction ,CARBON MOLECULAR-SIEVE ,0105 earth and related environmental sciences ,Diethylamine ,Original Paper ,Low-molecular-weight aliphatic amines ,010401 analytical chemistry ,Extraction (chemistry) ,Mesoporous silica ,Divinylbenzene ,Functionalized mesoporous silica material ,0104 chemical sciences ,Atmospheric air ,chemistry ,Gas chromatography-mass spectrometry ,Ethylamine ,Mesoporous material ,Selectivity ,Nuclear chemistry - Abstract
Mesoporous silica-coated solid phase microextraction (SPME) Arrow systems were developed for capturing of low-molecular-weight aliphatic amines (LMWAAs) from complicated sample matrices. Specifically, silicas of type MCM-41, SBA-15 and KIT-6 were chosen as substrates to afford size-exclusion selectivity. They possess ordered multidimensional pore-channel structures and mesopore sizes between 3.8 and 8.2 nm. Their surface acidity was enhanced by grafting them with a layer of titanium hydrogenphosphate (-TP). This enhanced the chemical selectivity for basic LMWAAs. The siliceous coatings increased the extraction of ethylamine, diethylamine (DEA) and triethylamine (TEA) by factors of 18.6–102.5, 4.8–10.8 and 2.6–4.0, respectively, when compared to the commercial SPME Arrow with polydimethylsiloxane/divinylbenzene coating. Among them, the MCM-41 and MCM-41-TP coated SPME Arrows demonstrated exceptional selectivity towards LMWAAs that were quantified by gas chromatography-mass spectrometry (GC-MS). The total peak area ratios of LMWAAs/ten competing compounds were 25.4 and 36.3, respectively. The extraction equilibrium was reached within 20–30 min. The MCM-41 and MCM-41-TP derived SPME Arrows gave very similar results (18.4 ± 2.1–376 ± 12 ng g−1 to DEA and TEA) when applied to urban mushroom samples. SPME Arrow with MCM-41 coatings followed by GC-MS was applied also to the analysis of atmospheric air and urine samples resulting in high selectivity due to the size and mesoporous structure of the functionalized silica, and its chemical interactions with the LMWAAs. Graphical abstractScheme of synthesis of the MCM-41 silicas, and the preparation of solid phase microextraction Arrow coatings. They were employed for selective capturing of aliphatic amines from complex sample matrices, followed by gas chromatography-mass spectrometry. Electronic supplementary material The online version of this article (10.1007/s00604-019-3523-5) contains supplementary material, which is available to authorized users.
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- 2019
241. Antibiotic Resistance Genes in the Human-Impacted Environment : A One Health Perspective
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Tong Zhang, James M. Tiedje, Fang Wang, Liping Ma, Hongjie Sheng, Edward Topp, Marko Virta, Célia M. Manaia, Department of Microbiology, Helsinki One Health (HOH), and Veritati - Repositório Institucional da Universidade Católica Portuguesa
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WATER TREATMENT PLANTS ,BIOAVAILABILITY ,Soil Science ,Aquaculture ,010501 environmental sciences ,Antimicrobial resistance ,human health ,01 natural sciences ,Antibiotic-resistant bacteria ,Antibiotic resistance ,WASTE-WATER ,IRRIGATION ,Health care ,Global health ,antimicrobial resistance ,Environmental planning ,1183 Plant biology, microbiology, virology ,0105 earth and related environmental sciences ,Animal agriculture ,2. Zero hunger ,antibiotic-resistant bacteria ,Resistance (ecology) ,business.industry ,wastewater and sludge ,One Health framework ,Human health ,04 agricultural and veterinary sciences ,6. Clean water ,3. Good health ,SOILS ,One Health ,Work (electrical) ,animal agriculture ,aquaculture ,13. Climate action ,ESCHERICHIA-COLI ,BACTERIA ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Biological dispersal ,ABUNDANCE ,Business ,DAIRY MANURE ,TETRACYCLINE ,Antibiotic resistance genes ,soil contamination - Abstract
Antibiotic resistance and its environmental component are gaining more attention as part of combating the growing healthcare crisis. The One Health framework, promulgated by many global health agencies, recognizes that antimicrobial resistance is a truly inter-domain problem in which human health, animal agriculture, and the environment are the core and interrelated components. This prospectus presents the status and issues relevant to the environmental component of antibiotic resistance, namely, the needs for advancing surveillance methodology: the environmental reservoirs and sources of resistance, namely, urban wastewater treatment plants, aquaculture production systems, soil receiving manure and biosolid, and the atmosphere which includes longer range dispersal. Recently, much work has been done describing antibiotic resistance genes in various environments; now quantitative, mechanistic, and hypothesis-driven studies are needed to identify practices that reduce real risks and maintain the effectiveness of our current antibiotics as long as possible. Advanced deployable detection methods for antibiotic resistance in diverse environmental samples are needed in order to provide the surveillance information to identify risks and define barriers that can reduce risks. Also needed are practices that reduce antibiotic use and thereby reduce selection for resistance, as well as practices that limit the dispersal of or destroy antibiotic-resistant bacteria or their resistance genes that are feasible for these varied environmental domains.
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- 2019
242. The utilization of struvite produced from human urine in agriculture as a natural fertilizer : a review
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Anikó Zseni, Surendra K. Pradhan, Judit Nagy, Anna Mikola, Budapest University of Technology and Economics, Water and Environmental Eng., Széchenyi István University, Department of Built Environment, Aalto-yliopisto, and Aalto University
- Subjects
IMPACTS ,Struvite ,PH ,General Chemical Engineering ,Urine ,engineering.material ,Natural (archaeology) ,chemistry.chemical_compound ,SOURCE-SEPARATED URINE ,WASTE-WATER ,human urine ,Dry toilets ,Precipitation ,Urine-diversion dry toilets ,Sustainable development ,sustainable development ,Waste management ,business.industry ,REMOVING PHOSPHORUS ,Agriculture ,RECOVERY ,Wastewater ,chemistry ,PRECIPITATION ,engineering ,urine-division dry toilets ,Environmental science ,Fertilizer ,business - Abstract
Most of the nutrients in municipal wastewater originate from urine. Nevertheless, chemical fertilizers are commonly used in the agriculture instead of urine. There are some problems related to the direct utilization of urine, such as micropollutants present in urine, odour and storage of large volume of urine. In wastewater, phosphorus may contribute significantly to the pollution of the aquatic systems. Therefore, wastewater treatment techniques are mainly focusing on removing phosphorus. Phosphorus is collected in the sludge either by a chemical or by a biological process. With the growing concern of micropollutants present, which are in the sludge, the use of sludge in agriculture has been gradually decreasing. It means that the phosphorus content in sludge is not recycled efficiently whereas the use of limited mineral phosphorus resources is growing. To overcome these issues, urine could be collected separately and struvite could be produced. This may recover about 90 % of phosphate in urine. In this paper, the use of human urine and struvite as a fertilizer in the agriculture and the production of struvite is discussed. Results showed that the struvite could be an effective natural fertilizer.
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- 2019
243. Performance Comparison of Chemically Modified Sugarcane Bagasse for Removing Cd(II) in Water Environment
- Author
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Manh Khai Nguyen, Minh Trang Hoang, Thi Thuy Pham, and Bart Van der Bruggen
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Technology ,ADSORPTION ,Materials Science (miscellaneous) ,Materials Science ,Polymer Science ,Environmental Science (miscellaneous) ,PB(II) ,WASTE-WATER ,PESTICIDES ,AQUEOUS-SOLUTIONS ,Water environment ,Green & Sustainable Science & Technology ,Science & Technology ,Chemistry ,citric acid ,Pulp and paper industry ,NI(II) ,ADSORBENTS ,sugarcane bagasse ,CU(II) ,HEAVY-METAL IONS ,CADMIUM(II) ,Performance comparison ,Materials Science, Composites ,Physical Sciences ,Science & Technology - Other Topics ,Bagasse ,chemical modification ,Cadmium - Abstract
© 2019 Tech Science Press. This paper evaluates the adsorption capacity of chemically sugarcane bagasses with sodium hydroxide (SHS), citric acid (CAS), tartaric acid (TAS) and unmodified sugarcane bagasse (SB) for cadmium adsorption in water environment. The results prove adsorption capacity for Cd (II) increases after chemical modification and the adsorption fits perfectly with the Langmuir isotherm. CAS had the highest maximum adsorption capacity of 45.45 mg/g followed by TAS with 38.46 mg/g and SHS with 29.41 at optimum pH 5.0 and 120 minutes equilibrium time while 1 g SB removed 18.8 mg Cd (II) in the same conditions. The kinetics study of the process followed a pseudo-second-order rate expression, that indicated a strong interaction between the biosorbents and adsorbate. The sugarcane bagasse and modified sugarcane bagasse were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The chemical modification was confirmed by the presence of carboxyl and esters groups created at 1,738 cm-1. The estimation of acid groups in modified materials shows the enhancement of this group after modification. On the other hand, desorption studies showed the high leaching of cadmium ion from the biosorbent leading to the efficient re-utilization of materials. ispartof: JOURNAL OF RENEWABLE MATERIALS vol:7 issue:5 pages:415-428 status: published
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- 2019
244. Encapsulation of heavy metals by a nanoporous complex oxide 12CaO center dot 7Al(2)O(3)
- Author
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Kuganathan, N, Grimes, RW, and Chroneos, A
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IONS ,Science & Technology ,02 Physical Sciences ,Physics ,EFFICIENT ,09 Engineering ,Physics, Applied ,SOILS ,CARBON ,REMOVAL ,WASTE-WATER ,POLLUTION ,Physical Sciences ,RISK-ASSESSMENT ,01 Mathematical Sciences ,Applied Physics - Abstract
The nanoporous oxide 12CaO ⋅ 7Al2O3 (C12A7) offers the possibility of capturing large concentrations of environmentally damaging extra-framework species in its nanopores. Using density functional theory with a dispersion correction, we predict the structures and energetics of some heavy metals (Cr, Ni, Cu, Zn, Cd, Hg, and Pb) trapped by the stoichiometric and electride form of C12A7. In the stoichiometric form, while Zn, Cd, Hg, and Pb are encapsulated weakly, Cr, Ni, and Cu exhibit strong encapsulation energies. The electride form of C12A7 shows a significant enhancement in the encapsulation of Cr, Ni, Cu, and Pb. Successive encapsulation of multiple Cr, Ni, Cu, and Pb as single species in adjacent cages of C12A7 is also energetically favorable.
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- 2019
245. Photocatalytic degradation of binary and ternary mixtures of antibiotics reactive species investigation in pilot scale
- Author
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Mahamadou Kamagate, Aymen Amine Assadi, Sami Rtimi, Lassina Sandotin Coulibaly, Hichem Zeghioud, Badji Mokhtar-Annaba University, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Man, Ecole Polytechnique Fédérale de Lausanne (EPFL), Université Badji Mokhtar Annaba (UBMA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Radical scavengers ,Surface characterization ,waste-water ,General Chemical Engineering ,Radical ,02 engineering and technology ,010501 environmental sciences ,dielectric barrier discharge ,pharmaceuticals ,01 natural sciences ,Mineralization (biology) ,photochemical fate ,Catalysis ,chemistry.chemical_compound ,[CHIM.GENI]Chemical Sciences/Chemical engineering ,Fourier transform infrared spectroscopy ,advanced oxidation ,Binary/Ternary compounds system ,Photocatalytic degradation ,0105 earth and related environmental sciences ,Chemistry ,[SDE.IE]Environmental Sciences/Environmental Engineering ,removal ,Mono-compound system ,Antibiotic mixture ,risk-assessment ,tio2 ,General Chemistry ,021001 nanoscience & nanotechnology ,binary/temary compounds system ,Ternary compound ,kinetics ,Photocatalysis ,Degradation (geology) ,photodegradation ,0210 nano-technology ,Ternary operation ,Nuclear chemistry - Abstract
The present study investigates the photocatalytic degradation of three quinolone antibiotics (i.e., Flumequine (FLU), Oxolinic Acid (OA) and Nalidixic Acid (NA)) in mono-, binary and ternary compound systems. The closed-loop step photo-reactor and TiO2 impregnated on cellulosic paper as supported photo-catalyst in presence of UV light irradiation were used. The degradation of FLU occurred within 4 h. A 65.4% mineralization of OA was observed in a mono-compound system, due to the fast conversion of these main by-products formed. Besides, the investigation of the contribution of free radicals revealed the involvement of hole (h(+)), O-2(center dot-), but mainly "OH on the degradation of OA. The second-order kinetic rate constants calculated relative to the contribution of (OH)-O-center dot radicals on the degradation of OA was 4.03 x 10(9) M(-1)s(-1), whereas for that of NA was 4.42 x 10(9) M(-1)s(-1), thus underscoring that (OH)-O-center dot coproduct is the primary reactive species implicated in the photocatalytic degradation of these compounds on TiO2/cellulosic paper catalysts. The mono-compound system shows a higher degradation rate compared to multi-compound system (binary and ternary) which explained by the competitive adsorption of antibiotics on the available active sites of photocatalyst surface. Overall, the constant photocatalytic rates are higher following this order: mono compound system > ternary mixture >binary mixture. The catalyst was characterized by mean of FTIR, HR-TEM and XRD. The SiO2-binder role was discussed in details based on the atomic distribution of elements on the cellulose fibers as shown by the EDS atomic mapping. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
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- 2019
246. Optimization of phosphate recovery from urine by layered double hydroxides
- Author
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Kris Dox, Roel Merckx, Maarten Everaert, and Erik Smolders
- Subjects
ADSORPTION ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Coprecipitation ,Layered double hydroxide (LDH) ,Environmental Sciences & Ecology ,010501 environmental sciences ,engineering.material ,Urine ,SORPTION ,X-ray diffraction (XRD) ,01 natural sciences ,Phosphates ,STRUVITE ,chemistry.chemical_compound ,REMOVAL ,Adsorption ,WASTE-WATER ,Recovery ,Desorption ,Hydroxides ,Environmental Chemistry ,MG-AL ,Waste Management and Disposal ,BATCH ,0105 earth and related environmental sciences ,Science & Technology ,Ion exchange ,Layered double hydroxides ,Phosphorus ,Sorption ,Phosphate ,Pollution ,chemistry ,Models, Chemical ,Struvite ,FERTILIZERS ,engineering ,Life Sciences & Biomedicine ,Environmental Sciences ,Water Pollutants, Chemical ,Nuclear chemistry - Abstract
Urine contains sufficient phosphorus (P) to consider P recycling form urine as an interesting strategy. In this study, the potential of MgAl or ZnAl layered double hydroxides (LDHs) to be used in such recovery was assessed. LDHs are anion exchangers with a high P selectivity, and P-loaded LDHs have demonstrated fertiliser potential. A critical factor for efficient P recycling with LDH is the stability of these materials, which can be compromised by urinary citrate, complexing aluminium (Al3+) and by the low pH of fresh urine dissolving the alkaline LDHs. Different phase pure ZnAl and MgAl LDHs were synthesised by coprecipitation in scenarios of varying synthesis pH and Mg/Al or Zn/Al ratios. The obtained materials were incubated in P solutions at different pH, with or without citrate in full factorial combinations, and in fresh and stored human urine. The P sorption capacities increased for LDHs synthesised at lower pH, at increasing Al content and for sorption solutions with lower pH. These trends are explained by an increased anion exchange capacity (AEC) and by P speciation (charge) in the LDHs, an interpretation supported by XRD measurements. The P capacity reached 61mg P/g LDH, which equals 85% of the theoretical LDH exchange capacity. Only 1g LDH is required to remove 90% of P from 1L urine and evidence is found that sorption, not struvite precipitation, is the P removal mechanism involved. The ZnAl LDHs were equally effective in P uptake compared to the MgAl LDHs, but the ZnAl materials showed more irreversible P sorption in contrast with the high desorption yields (53mg P/g) of the MgAl LDHs. Therefore, the large potential of MgAl LDHs for P recovery from urine is supported by this study. ispartof: SCIENCE OF THE TOTAL ENVIRONMENT vol:682 pages:437-446 ispartof: location:Netherlands status: published
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- 2019
247. Global multi-pollutant modelling of water quality: scientific challenges and future directions
- Author
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Carolien Kroeze, Yoshihide Wada, Mengru Wang, Martina Flörke, J. Emiel Spanier, Richard J. Williams, Ting Tang, Jikke van Wijnen, Nynke Hofstra, Wietse Franssen, Michelle T. H. van Vliet, Simon J. Langan, Albert A. Koelmans, and Maryna Strokal
- Subjects
INDICATORS ,Microplastics ,Aquatic Ecology and Water Quality Management ,South asia ,010504 meteorology & atmospheric sciences ,Climate change ,010501 environmental sciences ,01 natural sciences ,Ecology and Environment ,EMERGING POLLUTANTS ,INTEGRATED MODEL ,WASTE-WATER ,Multi pollutant ,SURFACE-WATER ,CRYPTOSPORIDIUM EMISSIONS ,Life Science ,0105 earth and related environmental sciences ,General Environmental Science ,DISCHARGE ,Pollutant ,WIMEK ,CLIMATE-CHANGE ,business.industry ,Environmental resource management ,General Social Sciences ,Aquatische Ecologie en Waterkwaliteitsbeheer ,PHOSPHORUS ,Environmental Systems Analysis ,Milieusysteemanalyse ,EUTROPHICATION ,Environmental science ,Water Systems and Global Change ,Water quality ,business ,River pollution - Abstract
Assessing global water quality issues requires a multi-pollutant modelling approach. We discuss scientific challenges and future directions for such modeling. Multi-pollutant river models need to integrate information on sources of pollutants such as plastic debris, nutrients, chemicals, pathogens, their effects and possible solutions. In this paper, we first explain what we consider multi-pollutant modelling. Second, we discuss scientific challenges in multi-pollutant modelling relating to consistent model inputs, modelling approaches and model evaluation. Next, we illustrate the potential of global multi-pollutant modelling for hotspot analyses. We show hotspots of river pollution with microplastics, nutrients, triclosan and Cryptosporidium in many sub-basins of Europe, North America and South Asia. Finally, we reflect on future directions for multi-pollutant modelling, and for linking model results to policy-making.
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- 2019
248. Risk-management tool for environmental prioritization of pharmaceuticals based on emissions from hospitals
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Kevin Tipatet, Henry Beeltje, Ad M.J. Ragas, Cornelis van Loon, E.W.M. Roex, Marijn Gülpen, Leo Posthuma, Caterina Zillien, Birgit Hanssen, Rik Oldenkamp, RS-Research Line Learning (part of LIRS program), and Academic Field Science
- Subjects
Prioritization ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,METFORMIN ,Urbanisation ,DICLOFENAC ,010501 environmental sciences ,01 natural sciences ,Prescription data ,Aquatic organisms ,PERSONAL CARE PRODUCTS ,WASTE-WATER ,SURFACE-WATER ,Health care ,Environmental Chemistry ,Medical prescription ,Waste Management and Disposal ,Risk management ,0105 earth and related environmental sciences ,Hospital effluent ,Risk Management ,Impact estimation ,business.industry ,Environmental risk assessment ,Pollution ,Hospitals ,Passive sampling ,Risk analysis (engineering) ,Pharmaceutical Preparations ,Relative risk ,Ranking ,business ,Environment & Sustainability ,ANTIBIOTICS ,Environmental Sciences ,Water Pollutants, Chemical ,Environmental Monitoring ,Emission modelling - Abstract
Over the past decade, the health care sector has become increasingly aware of the impact of pharmaceutical emissions to the environment. Yet, it remains unclear which compounds are the most relevant to address and at what point emission control is most effective. This study presents a modelling framework to prioritize pharmaceuticals based on their relative risks for aquatic organisms, using purchase and prescription data from hospitals. The framework consists of an emission prediction module and a risk prioritization module. The emission prediction module accounts for three different routes of intake (oral, intravenous, rectal), for non-patient consumption, and for delayed athome excretion due to relatively long half-lives or prescription durations of selected pharmaceuticals. We showcase the modelling framework with 16 pharmaceuticals administered at two Dutch academic hospitals. Predictions were validated with experimental data from passive sampling in the sewer system. With the exception of metformin, all predictions were within a factor of 10 from measurements. The risk prioritization module ranks each pharmaceutical based on its predicted relative risk for aquatic organisms. The resulting prioritization suggests that emission mitigation strategies should mainly focus on antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs).
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- 2019
249. Symbiotic Co-Culture of Scenedesmus sp. and Azospirillum brasilense on N-Deficient Media with Biomass Production for Biofuels
- Author
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Rashmi Chandra, Nídia S. Caetano, Koenraad Muylaert, Jose R. Contreras-Angulo, J. Saúl García-Pérez, Teresa M. Mata, Sara P. Cuellar-Bermudez, Roberto Parra-Saldívar, and Faculdade de Engenharia
- Subjects
Geography, Planning and Development ,Environmental Studies ,Biomass ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,7. Clean energy ,Renewable energy sources ,0202 electrical engineering, electronic engineering, information engineering ,GE1-350 ,Food science ,Green & Sustainable Science & Technology ,Scenedesmus ,biology ,Environmental effects of industries and plants ,Chemistry ,6. Clean water ,PHOSPHORUS ,Wastewater ,Biofuel ,BACTERIA ,Science & Technology - Other Topics ,GROWTH ,Aeration ,nitrogen concentration ,LIPID-ACCUMULATION ,Life Sciences & Biomedicine ,OBLIQUUS ,020209 energy ,TJ807-830 ,Environmental Sciences & Ecology ,Azospirillum brasilense ,Management, Monitoring, Policy and Law ,TD194-195 ,microalgae-bacteria co-culturing ,Dry weight ,WASTE-WATER ,Bioenergy ,ALGINATE BEADS ,MICROALGAE CHLORELLA-VULGARIS ,Scenedesmus sp ,0105 earth and related environmental sciences ,Science & Technology ,Renewable Energy, Sustainability and the Environment ,Building and Construction ,AMMONIUM ,biology.organism_classification ,Environmental sciences ,SPP ,mixing system ,Environmental Sciences - Abstract
The treatment of nitrogen-deficient agriculture wastewater, arising from the vegetable and fruit processing, is a significant problem that limits the efficiency of its biological treatment. This study evaluates the effectiveness of the symbiotic co-culture of Azospirillum brasilense and Scenedesmus sp., under two nitrogen levels (8.23 mg L&minus, 1 and 41.17 mg L&minus, 1) and mixing systems (aeration and magnetic stirring), aiming to simultaneously use the N-deficient media for their growth while producing biomass for biofuels. Microalgae growth and biomass composition, in terms of protein, carbohydrate and fatty acid contents, were evaluated at the end of the exponential growth phase (15 days after inoculation). Results show that the symbiotic co-culture of microalgae-bacteria can be effectively performed on nitrogen-deficient media and has the potential to enhance microalgae colony size and the fatty acid content of biomass for biofuels. The highest biomass concentration (103 ±, 2 mg·, L&minus, 1) was obtained under aeration, with low nitrogen concentration, in the presence of A. brasilense. In particular, aeration contributed to, on average, a higher fatty acid content (48 ±, 7% dry weight (DW)) and higher colony size (164 ±, 21 µ, m2) than mechanical stirring (with 39 ±, 2% DW and 134 ±, m2, respectively) because aeration contribute to better mass transfer of gases in the culture. Also, co-culturing contributed in average, to higher colony size (155 ±, m2) than without A. brasilense (143 ±, m2). Moreover, using nitrogen deficient wastewater as the culture media can contribute to decrease nitrogen and energy inputs. Additionally, A. brasilense is approved and already extensively used in agriculture and wastewater treatment, without known environmental or health issues, simplifying the biomass processing for the desired application.
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- 2019
250. Development and application of relevance and reliability criteria for water treatment removal efficiencies of chemicals of emerging concern
- Author
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Annemarie P. van Wezel, A.C. Fischer, Emile Cornelissen, Juliane Hollender, Roberta Hofman, Jan Peter van der Hoek, Nanyang Environment and Water Research Institute, and Singapore Membrane Technology Centre
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Environmental Engineering ,Technology and Engineering ,PHARMACEUTICALLY ACTIVE COMPOUNDS ,Computer science ,Data evaluation criteria ,Chemicals of emerging concern ,Advanced water treatment technologies ,Removal efficiency ,Drinking water ,Wastewater ,0208 environmental biotechnology ,DRINKING-WATER ,02 engineering and technology ,ADVANCED OXIDATION PROCESSES ,010501 environmental sciences ,01 natural sciences ,Water Purification ,ENDOCRINE DISRUPTING COMPOUNDS ,WASTE-WATER ,AQUEOUS-SOLUTIONS ,Production (economics) ,Relevance (information retrieval) ,NATURAL ORGANIC-MATTER ,Waste Management and Disposal ,Reliability (statistics) ,0105 earth and related environmental sciences ,Water Science and Technology ,Civil and Structural Engineering ,Ecological Modeling ,Treatment process ,Reproducibility of Results ,Water ,Data interpretation ,Pollution ,CARE PRODUCTS PPCPS ,Environmental engineering [Engineering] ,020801 environmental engineering ,BISPHENOL-A ,Risk analysis (engineering) ,Aquatic environment ,Earth and Environmental Sciences ,AROMATIC PESTICIDES ,Water treatment ,Water Pollutants, Chemical - Abstract
With the growth in production and use of chemicals and the fact that many end up in the aquatic environment, there is an increasing need for advanced water treatment technologies that can remove chemicals of emerging concern (CECs) from water. The current lack of a homogenous approach for testing advanced water treatment technologies hampers the interpretation and evaluation of CEC removal efficiency data, and hinders informed decision making by stakeholders with regard to which treatment technology could satisfy their specific needs. Here a data evaluation framework is proposed to improve the use of current knowledge in the field of advanced water treatment technologies for drinking water and wastewater, consisting of a set of 9 relevance criteria and 51 reliability criteria. The two criteria sets underpin a thorough, unbiased and standardised method to select studies to evaluate and compare CEC removal efficiency of advanced water treatment technologies in a scientifically sound way. The relevance criteria set was applied to 244 papers on removal efficiency, of which only 20% fulfilled the criteria. The reliability criteria were applied to the remaining papers. In general these criteria were fulfilled with regards to information on the target compound, the water matrix and the treatment process conditions. However, there was a lack of information on data interpretation and statistics. In conclusion, a minority of the evaluated papers are suited for comparison across techniques, compounds and water matrixes. There is a clear need for more uniform reporting of water treatment studies for CEC removal. In the future this will benefit the selection of appropriate technologies., Water Research, 161, ISSN:0043-1354, ISSN:1879-2448
- Published
- 2019
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