1,592 results
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2. Thanatochemistry at the crime scene: a microfluidic paper-based device for ammonium analysis in the vitreous humor.
- Author
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Musile G, Agard Y, De Palo EF, Shestakova K, Bortolotti F, and Tagliaro F
- Subjects
- Adult, Aged, Colorimetry instrumentation, Colorimetry methods, Forensic Medicine instrumentation, Humans, Iodides chemistry, Limit of Detection, Mercury Compounds chemistry, Microfluidic Analytical Techniques instrumentation, Microfluidic Analytical Techniques methods, Middle Aged, Proof of Concept Study, Reproducibility of Results, Time Factors, Young Adult, Ammonium Compounds analysis, Forensic Medicine methods, Paper, Postmortem Changes, Vitreous Body chemistry
- Abstract
Most of the on-site approaches for inferring of the post-mortem interval are still based on observative data from the direct body inspection, whereas, objective and quantitative analyses, such as potassium in the vitreous humor, are require laboratory instrumentation and skilled personnel. The present paper presents a simple and low cost analytical method suitable for use at the crime scene for inferring the time since death. The method uses a microfluidic paper-based device (μPAD) for the determination of ammonium in the vitreous humor (VH) based on the selective interaction between the ammonium and the Nessler's reagent. The color change was measured in terms of "RGB distance" by using a simple and free smartphone application. The optimized device showed a limit of detection of 0.4 mmol L
-1 , with between days precision less than 9.3% expressed as relative standard deviation, and accuracy between days from 94.5% to 104.5%. The selectivity of the Nessler's reaction was tested towards the main vitreous humor compounds, and no significant interferences were found. This paper-based analytical device was successfully used for the determination of ammonium ion in VH samples from forensic autopsies. The results obtained with the proposed method, although for a limited number of cases (n = 25), showed a close correlation with the data obtained with an instrumental analysis based on capillary electrophoresis. Moreover, in order to make the evaluation of results as simple as possible, a direct correlation between the color intensity, expressed as RGB distance, and the post-mortem interval was studied and a significant correlation was found (R2 > 0.78). In conclusion, the present preliminary study showes that the proposed device could be an additional tool to the traditional methods for a more accurate, although still presumptive, estimation of the time of death directly at the crime scene., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
- Full Text
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3. Suzuki C-C Coupling in Paper Spray Ionization: Microsynthesis of Biaryls and High-Sensitivity MS Detection of Aryl Bromides.
- Author
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Lin Q, Xue L, Sun J, Wang Y, and Cheng H
- Subjects
- Borates chemistry, Boronic Acids, Bromides chemistry, Mass Spectrometry, Persistent Organic Pollutants, Water, Ammonium Compounds, Flame Retardants
- Abstract
Suzuki-Miyaura cross-coupling is one of the most powerful strategies for constructing biaryl compounds. However, classic Suzuki-Miyaura coupling suffers from hour-scale reaction time and competitive protodeboronation. To address these problems, a mild nonaqueous potassium trimethylsilanolate (TMSOK)-assisted Suzuki-Miyaura coupling strategy was designed for the microsynthesis of biaryls in paper spray ionization (PSI). Due to the acceleration power facilitated by microdroplet chemistry in reactive PSI, the microsynthesis of biaryls by reactive PSI was accomplished within minutes with comparable yields to the bulk, showing good substrate applicability from 32 Suzuki-Miyaura reactions of aryl bromides and aryl boronic acid/borates bearing different substituents. Based on the above TMSOK-assisted Suzuki-Miyaura coupling strategy, we further developed a high-sensitivity and selective PSI mass spectrometry (MS) method for quantitative analysis of aryl bromides, a class of environmentally persistent organic pollutants that cannot be directly detected by ambient mass spectrometry due to their low ionization efficiency. In situ derivatization of aryl bromides was achieved with aryl borates bearing quaternary ammonium groups in PSI. The proposed PSI-MS method shows good linearity over the 0.01-10 μmol L
-1 range with low detection limits of 1.8-4.8 nmol L-1 as well as good applicability to the rapid determination of six aryl bromides in three environmental water samples. The proposed PSI-MS method also shows good applicability to brominated flame retardants (polybrominated diphenyls/diphenyl esters). Overall, this study provides a simple, rapid, low-cost, high-sensitivity, and high-selectivity strategy for trace aryl bromides and other brominated pollutants in real samples with minimal/no sample pretreatment.- Published
- 2022
- Full Text
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4. Replacing calcium with ammonium counterion in lignosulfonates from paper mills affects their molecular properties and bioactivity.
- Author
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Savy D, Cozzolino V, Drosos M, Mazzei P, and Piccolo A
- Subjects
- Chromatography, Gel, Industrial Waste, Lignin chemistry, Paper, Spectroscopy, Fourier Transform Infrared, Ammonium Compounds chemistry, Calcium chemistry, Lignin analogs & derivatives, Waste Disposal, Fluid methods
- Abstract
Lignosulfonates are important by-products of the paper industry and may be transformed into different commodities. We studied the molecular properties of ammonium (LS-AM) and calcium Lignosulfonates (LS-C) and evaluated their bioactivity towards the early development of maize plantlets. The FT-IR,
13 C NMR and1 H-13 C-HSQC-NMR spectra showed that the two lignosulfonates varied in hydroxyl, sulfonate and phenolic content, while DOSY-NMR spectroscopy suggested a similar diffusivity. High Performance Size Exclusion Chromatography (HPSEC) was used to simulate the effects of root-exuded acids and describe the conformational dynamics of both LS substrates in acidic aqueous solutions. This technique showed that LS-C was stabilized by the divalent Ca2+ counterion, thus showing a greater conformational stability than LS-AM, whose components could not be as efficiently aggregated by the monovalent NH4+ counter-ion. The plant bioassays revealed that LS-AM enhanced the elongation of the root system, whereas LS-C significantly increased both total and shoot plant weights. We concluded that the lignosulfonate bioactivity on plant growth depended on the applied concentrations, their molecular properties and conformational stability., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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5. Determination of ammonium and nitrate in soils by digital colorimetry.
- Author
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Garmay AV, Oskolok KV, Monogarova OV, and Demidov MI
- Subjects
- Colorimetry methods, Soil chemistry, Environmental Monitoring methods, Nitrates analysis, Soil Pollutants analysis, Ammonium Compounds analysis
- Abstract
A method of digital colorimetric determination of ammonium and nitrate in soils is proposed. The method is based on corresponding photometric procedures of ammonium and nitrate determination after potassium chloride extraction from soil samples. Ammonium is determined as an indophenol dye, and nitrate is determined as an azo dye. The original procedures were modified to overcome the lower sensitivity of the digital colorimetric method. For ammonium determination, the time required for the reaction to proceed completely was studied. Along with the use of a 96-well microplate protected from ambient light by a special frame, mathematical correction of scattered radiation using black ink and taking the images by a scanner in transmission mode without any post-processing, the resulting colorimetric methods proved to provide accuracy and sensitivity close to those of the spectrophotometric method, and the overall analysis speed for tens of samples was even higher. Limits of detection and quantitation for NO
3 - were 0.42 and 1.4 mg/kg, and for NH4 + , they were 1.1 and 3.7 mg/kg, which is lower than for standard methods. The methods' validity was proven by the analysis of standard samples and by the analysis of soil samples collected in several districts of the Moscow region., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)- Published
- 2024
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6. A note on paper chromatography of quaternary ammonium salts.
- Author
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ROSEN WE, TOOHEY VP, and SHABICA AC
- Subjects
- Ammonium Compounds analysis, Chromatography, Paper, Quaternary Ammonium Compounds analysis, Salts
- Published
- 1957
- Full Text
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7. PAPER CHROMATOGRAPHY OF MONOMER SUGARS USING QUATERNARY SALTS FOR IDENTIFICATION.
- Author
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ROSENTHAL WA, SPANER S, and BROWN KD
- Subjects
- Ammonium Compounds, Carbohydrates, Chromatography, Chromatography, Paper, Glucosamine, Glucose, Glucuronates, Hexosamines, Hexoses, Lactones, Mannose, Quaternary Ammonium Compounds, Research, Salts, Strychnos nux-vomica, Ultraviolet Rays, Uronic Acids
- Published
- 1964
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8. THE PAPER CHROMATOGRAPHY OF SOME ISOMERIC MONOSUBSTITUTED PHENOLS. I.
- Author
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GUMPRECHT DL
- Subjects
- Ammonium Compounds, Cerium, Chromatography, Chromatography, Paper, Isomerism, Nitrates, Phenols, Quaternary Ammonium Compounds, Research, Solvents, Toluene, Water
- Published
- 1965
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9. Paper chromatography of quaternary ammonium bases and related compounds.
- Author
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BREGOFF HM, ROBERTS E, and DELWICHE CC
- Subjects
- Ammonium Compounds, Chromatography, Chromatography, Paper, Quaternary Ammonium Compounds
- Published
- 1953
10. Ammonium nanochelators in conjunction with arginine-specific enzymes in amperometric biosensors for arginine assay.
- Author
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Stasyuk N, Gayda G, Nogala W, Holdynski M, Demkiv O, Fayura L, Sibirny A, and Gonchar M
- Subjects
- Urease chemistry, Arginine, Arginase metabolism, Ammonium Compounds, Biosensing Techniques
- Abstract
Amino acid L-arginine (Arg), usually presented in food products and biological liquids, can serve both as a useful indicator of food quality and an important biomarker in medicine. The biosensors based on Arg-selective enzymes are the most promising devices for Arg assay. In this research, three types of amperometric biosensors have been fabricated. They exploit arginine oxidase (ArgO), recombinant arginase I (ARG)/urease, and arginine deiminase (ADI) coupled with the ammonium-chelating redox-active nanoparticles. Cadmium-copper nanoparticles (nCdCu) as the most effective nanochelators were used for the development of ammonium chemosensors and enzyme-coupled Arg biosensors. The fabricated enzyme/nCdCu-containing bioelectrodes show wide linear ranges (up to 200 µM), satisfactory storage stabilities (14 days), and high sensitivities (A⋅M
-1 ⋅m-2 ) to Arg: 1650, 1700, and 4500 for ADI-, ArgO- and ARG/urease-based sensors, respectively. All biosensors have been exploited to estimate Arg content in commercial juices. The obtained data correlate well with the values obtained by the reference method. A hypothetic scheme for mechanism of action of ammonium nanochelators in electron transfer reaction on the arginine-sensing electrodes has been proposed., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)- Published
- 2023
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11. Trigeminal function in patients with COVID-associated olfactory loss.
- Author
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Juratli JH, Garefis K, Konstantinidis I, and Hummel T
- Subjects
- Humans, Anosmia etiology, Smell physiology, COVID-19 complications, Olfaction Disorders diagnosis, Olfaction Disorders etiology, Ammonium Compounds
- Abstract
Purpose: Olfactory dysfunction (OD) can be a long-term consequence of various viral infections, including COVID-19. Dysfunction includes hyposmia/anosmia and parosmia (odor distortions). Interactions of the virus with the olfactory nerve have been extensively researched, but little is known about the interactions of the intranasal trigeminal nerve system in modulating this sensory loss., Methods: We investigated intranasal trigeminal function across COVID-19 OD patients with and without parosmia compared to normosmic controls, to determine whether (1) post-viral hyposmia and/or (2) post-viral hyposmia with parosmia is associated with altered trigeminal function. OD patients (n = 27) were tested for olfactory function using the extended Sniffin' Sticks olfactory test and for trigeminal function through three methods-odor lateralization, subjective ratings of nasal patency, and ammonium vapor pain intensity ratings. This group was subsequently compared to controls, normosmic subjects (n = 15)., Results: Our findings revealed that post-COVID OD patients without parosmia experienced decreased sensitivity in ammonium vapor pain intensity ratings and odor lateralization scores-but similar nasal patency ratings-compared to normosmic controls. There were no significant differences in trigeminal function between OD patients with and without parosmia., Conclusions: Based on our results, we conclude that the trigeminal nerve dysfunction may partially explain post-viral OD, but does not seem to be a major factor in the generation of parosmia pathophysiology., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2024
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12. Resting cells of Skeletonema marinoi assimilate organic compounds and respire by dissimilatory nitrate reduction to ammonium in dark, anoxic conditions.
- Author
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Stenow R, Robertson EK, Kourtchenko O, Whitehouse MJ, Pinder MIM, Benvenuto G, Töpel M, Godhe A, and Ploug H
- Subjects
- Anaerobiosis, Darkness, Organic Chemicals metabolism, Spectrometry, Mass, Secondary Ion, Geologic Sediments microbiology, Carbon metabolism, Nitrogen metabolism, Nitrates metabolism, Ammonium Compounds metabolism, Oxidation-Reduction, Diatoms metabolism
- Abstract
Diatoms can survive long periods in dark, anoxic sediments by forming resting spores or resting cells. These have been considered dormant until recently when resting cells of Skeletonema marinoi were shown to assimilate nitrate and ammonium from the ambient environment in dark, anoxic conditions. Here, we show that resting cells of S. marinoi can also perform dissimilatory nitrate reduction to ammonium (DNRA), in dark, anoxic conditions. Transmission electron microscope analyses showed that chloroplasts were compacted, and few large mitochondria had visible cristae within resting cells. Using secondary ion mass spectrometry and isotope ratio mass spectrometry combined with stable isotopic tracers, we measured assimilatory and dissimilatory processes carried out by resting cells of S. marinoi under dark, anoxic conditions. Nitrate was both respired by DNRA and assimilated into biomass by resting cells. Cells assimilated nitrogen from urea and carbon from acetate, both of which are sources of dissolved organic matter produced in sediments. Carbon and nitrogen assimilation rates corresponded to turnover rates of cellular carbon and nitrogen content ranging between 469 and 10,000 years. Hence, diatom resting cells can sustain their cells in dark, anoxic sediments by slowly assimilating and respiring substrates from the ambient environment., (© 2024 The Authors. Environmental Microbiology published by John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
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13. Microorganisms uniquely capture and predict stony coral tissue loss disease and hurricane disturbance impacts on US Virgin Island reefs.
- Author
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Becker CC, Weber L, Llopiz JK, Mooney TA, and Apprill A
- Subjects
- Animals, Ecosystem, United States Virgin Islands, Coral Reefs, Water, Anthozoa, Cyclonic Storms, Ammonium Compounds
- Abstract
Coral reef ecosystems are now commonly affected by major climate and disease disturbances. Disturbance impacts are typically recorded using reef benthic cover, but this may be less reflective of other ecosystem processes. To explore the potential for reef water-based disturbance indicators, we conducted a 7-year time series on US Virgin Island reefs where we examined benthic cover and reef water nutrients and microorganisms from 2016 to 2022, which included two major disturbances: hurricanes Irma and Maria in 2017 and the stony coral tissue loss disease outbreak starting in 2020. The disease outbreak coincided with the largest changes in the benthic habitat, with increases in the percent cover of turf algae and Ramicrusta, an invasive alga. While sampling timepoint contributed most to changes in reef water nutrient composition and microbial community beta diversity, both disturbances led to increases in ammonium concentration, a mechanism likely contributing to observed microbial community shifts. We identified 10 microbial taxa that were sensitive and predictive of increasing ammonium concentration. This included the decline of the oligotrophic and photoautotrophic Prochlorococcus and the enrichment of heterotrophic taxa. As disturbances impact reefs, the changing nutrient and microbial regimes may foster a type of microbialization, a process that hastens reef degradation., (© 2024 The Authors. Environmental Microbiology published by John Wiley & Sons Ltd.)
- Published
- 2024
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14. Tropical bloom-forming mesoalgae Cladophoropsis sp. and Laurencia sp.-responses to ammonium enrichment and a simulated heatwave.
- Author
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Fricke A, Bast F, Moreira-Saporiti A, Martins Bussanello G, Msuya FE, and Teichberg M
- Subjects
- Chlorophyll A, Eutrophication, Laurencia, Ammonium Compounds, Chlorophyta
- Abstract
Algal blooms are increasing worldwide, driven by elevated nutrient inputs. However, it is still unknown how tropical benthic algae will respond to heatwaves, which are expected to be more frequent under global warming. In the present study, a multifactorial experiment was carried out to investigate the potential synergistic effects of increased ammonium inputs (25 μM, control at 2.5 μM) and a heatwave (31°C, control at 25°C) on the growth and physiology (e.g., ammonium uptake, nutrient assimilation, photosynthetic performance, and pigment concentrations) of two bloom-forming algal species, Cladophoropsis sp. and Laurencia sp. Both algae positively responded to elevated ammonium concentrations with higher growth and chlorophyll a and lutein concentrations. Increased temperature was generally a less important driver, interacting with elevated ammonium by decreasing the algaes' %N content and N:P ratios. Interestingly, this stress response was not captured by the photosynthetic yield (Fv/Fm) nor by the carbon assimilation (%C), which increased for both algae at higher temperatures. The negative effects of higher temperature were, however, buffered by nutrient inputs, showing an antagonistic response in the combined treatment for the concentration of VAZ (violaxanthin, antheraxanthin, zeaxanthin) and thalli growth. Ammonium uptake was initially higher for Cladophoropsis sp. and increased for Laurencia sp. over experimental time, showing an acclimation capacity even in a short time interval. This experiment shows that both algae benefited from increased ammonium pulses and were able to overcome the otherwise detrimental stress of increasingly emerging temperature anomalies, which provide them a strong competitive advantage and might support their further expansions in tropical marine systems., (© 2024 The Authors. Journal of Phycology published by Wiley Periodicals LLC on behalf of Phycological Society of America.)
- Published
- 2024
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15. Evaluation of nutrient assimilative capacity in waterfowl impoundments: The role of environmental stressors.
- Author
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Wood RL, Stark JM, Aanderud ZT, and Baker MA
- Subjects
- Wetlands, Nitrogen, Phosphorus, Nutrients, Nitrates, Ammonium Compounds
- Abstract
The effectiveness of wetlands in sequestering nutrients and improving water quality relies on a suite of abiotic and biotic conditions. To more fully understand the restraints on nutrient removal, especially salinity and plant cover, we created field-scale mesocosms and monitored nutrient sequestration with nutrient additions and isotopic pool dilutions over 2 years in two wetlands near the Great Salt Lake in Utah. Surprisingly, we found no differences in nutrient removal with plant removal, increased salinity, and altered ambient nutrient concentrations, suggesting functional redundancy in associated primary producers. When submerged aquatic vegetation was removed, chlorophyll α concentration (0.1-9.0 μg/L) increased while nitrogen (N) and phosphorus (P) assimilation remained the same as phytoplankton occupied the open niche space. We did find ammonium concentrations to be inversely related to nitrate assimilation-as the ammonium concentration increased, nitrate assimilation decreased, suggesting preferential uptake of ammonium. Last, in our high N and P treatment mesocosms, the nitrate dramatically declined from 43.9 mg/L to background levels (<0.1 mg/L) within 1 week, showing a high potential for N remediation in these wetlands., (© 2023 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)
- Published
- 2023
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16. Preparation of a Crosslinking Cassava Starch Adhesive and its Application in Coating Paper.
- Author
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Songlin Wang, Fangfang Zhang, Fushan Chen, and Zhiqiang Pang
- Subjects
- *
CASSAVA starch , *PAPER coatings , *PARTICLE size distribution , *SCANNING electron microscopy , *AMYLASES , *AMMONIUM compounds , *TEMPERATURE effect - Abstract
A new starch-based adhesive with high solid content, high binding force, and low viscosity was prepared via hydrolysis of cassava starch with α-amylase using glycerol as a plasticizer and Ammonium Zirconium Carbonate (AZC) as a crosslinker. The adhesive was applied to coated paper as a partial substitute for SBR latex. The effects of α-amylase, glycerol, AZC, and temperature on the starch adhesive and its performance in application were investigated. The prepared crosslinking cassava starch adhesive showed a significant effect when the starch slurry concentration was 50% (w/w), the dosages of glycerol and α-amylase were 15% and 0.075%, respectively, and the enzymolysis starch was crosslinked with 12% AZC at 50 °C. The modified starch improved the paper in terms of surface strength, gloss, whiteness, and smoothness when 20% SBR latex was substituted into the coating formulation. Statistical analysis indicated that the crosslinking temperature and AZC had significant effects on the performance of the paper, while glycerin and α-amylase had little effect on it. Spectral analysis of the product showed that the crosslinking reaction took place between AZC and cassava starch. The average particle size was 528.6 nm. Scanning Electron Microscope (SEM) images of the paper surface were consistent with the other measured surface properties. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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17. Partial denitrification-anammox (PdNA) application in mainstream IFAS configuration using raw fermentate as carbon source.
- Author
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Ladipo-Obasa M, Forney N, Riffat R, Bott C, deBarbadillo C, and De Clippeleir H
- Subjects
- Anaerobic Ammonia Oxidation, Bioreactors, Carbon, Denitrification, Methanol, Nitrates, Nitrification, Nitrogen, Oxidation-Reduction, Wastewater, Ammonium Compounds, Sewage
- Abstract
This research examined the feasibility of raw fermentate for mainstream partial denitrification-anammox (PdNA) in a pre-anoxic integrated fixed-film activated sludge (IFAS) process. Fermentate quality sampled from a full-scale facility was highly dynamic, with 360-940 mg VFA-COD/L and VFA/soluble COD ratios ranging from 24% to 48%. This study showed that PdNA selection could be achieved even when using low quality fermentate. Nitrate residual was identified as the main factor driving the PdN efficiency, while management of nitrate conversion rates was required to maximize overall PdNA rates. AnAOB limitation was never observed in the IFAS system. Overall, this study showed PdN efficiencies up to 38% and PdNA rates up to 1.2 ± 0.7 g TIN/m
2 /d with further potential for improvements. As a result of both PdNA and full denitrification, this concept showed the potential to save 48-89% methanol and decrease the carbon footprint of water resource recovery facilities (WRRF) by 9-15%. PRACTITIONER POINTS: Application of PdNA with variable quality fermentate is feasible when the nitrate residual concentration is increased to enhance PdN selection. To maximize nitrogen removed through PdNA, nitrate conversion rates need enhancement through optimization of upstream aeration and PdN control setpoints. The IFAS PdNA process was never anammox limited; success depended on the degree of PdN achieved to make nitrite available. Application of PdNA with fermentate can yield 48-89% savings in methanol or other carbon compared with conventional nitrification and denitrification. Integrating PdNA upstream from polishing aeration and anoxic zones guarantees that stringent limits can be met (<5 mg N/L)., (© 2022 Water Environment Federation.)- Published
- 2022
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18. Study of the influence of surfactants on the paper properties and degradation.
- Author
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Liubinienė, Milda, Kupčiūnaitė, Justė, and Beganskienė, Aldona
- Subjects
SURFACE active agents ,AMMONIUM compounds ,CHEMICAL decomposition ,HYDROLYSIS ,ACIDIFICATION - Abstract
Surfactants are one of the materials recommended for the cleaning of movable cultural properties. These substances are widespread in other fields - medicine, cosmetics, household appliance industry, etc. Quaternary ammonium compounds are particularly prevalent due to their cleansing and disinfectant properties. Initial studies have shown that surfactants, including quaternary ammonium compounds, have a positive effect on preserved/restored cultural properties. Using relatively low concentrations of aqueous solutions of these substances, it is possible to obtain sufficiently good results to wash out from the restoration of the document or textiles dirt, acidification of the object and colour changes that cause aging and decomposition processes - hydrolysis and oxidation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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19. Improvement of soil acidification and ammonium nitrogen content in tea plantations by long-term use of organic fertilizer.
- Author
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Ye J, Wang Y, Wang Y, Hong L, Kang J, Jia Y, Li M, Chen Y, Wu Z, and Wang H
- Subjects
- Animals, Sheep, Fertilizers analysis, Tea, Ecosystem, Nitrogen metabolism, Manure, Soil Microbiology, Hydrogen-Ion Concentration, Soil chemistry, Ammonium Compounds
- Abstract
Soil acidification is common in some Chinese tea plantations, which seriously affected growth of tea trees. Hence, it is essential to explore soil remediation in acidified tea plantations for sustainable development of the tea industry. We sought to determine how different fertilizers affect acidified soil and their N transformation in tea plantations. Different fertilizers were used on acidified tea plantation soils for 4 years (2017-2021), and changes in soil pH, indices related to soil N transformation and tea yield were analysed to construct interaction networks of these indices and find which had the largest influence on fertilization. Long-term use of sheep manure reduced soil acidification, increased soil pH, enhanced the number and intensity of N-fixing and ammonifying bacteria, urease, protease, asparaginase and N-acetamide glucose ribosidase activity and nifH gene expression. This treatment reduced the number and intensity of soil nitrifying and denitrifying bacteria, nitrate reductase and nitrite reductase activity, while the expression of amoA-AOA, nirK, nirS, narG and nosZ in turn increased ammonium N content of the soil, reduced nitrate N content, and enhanced tea yield. Topsis index weight analysis showed that ammonium N content in the soil had the largest impact among fertilization effects. Long-term use of sheep manure was beneficial in restoring the balance of the micro-ecosystem in acidified soil. This study provides an important practical basis for soil remediation and fertilizer management in acidified tea plantation soils., (© 2023 German Society for Plant Sciences and the Royal Botanical Society of the Netherlands.)
- Published
- 2023
- Full Text
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20. Multizone Aquatic Ecological Exposures to Landfill Contaminants from a Groundwater Plume Discharging to a Pond.
- Author
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Hua T, Propp VR, Power C, Brown SJ, Collins P, Smith JE, and Roy JW
- Subjects
- Ponds, Ecosystem, Saccharin, Chlorides, Waste Disposal Facilities, Environmental Monitoring, Water Pollutants, Chemical analysis, Groundwater, Ammonium Compounds
- Abstract
While it is recognized that groundwater contaminant plumes can impact surface waters, there remains little information on the magnitude, spatial extent, and especially temporal variability of the resulting exposure to the variety of aquatic organisms, particularly for stagnant surface waters (e.g., ponds). The present study of a historic landfill plume discharging to a pond investigated contaminant exposure to multiple aquatic zones (endobenthic, epibenthic, pelagic) over approximately 1 year within a temperate climate. Landfill tracers included the artificial sweetener saccharin, ammonium, chloride, and specific conductance. Sampling of pond sediment porewater (upwelling groundwater) and continuous geophysical imaging of the subsurface showed a relatively stable plume footprint covering approximately 26% of the pond, although with spatially varying leachate composition, revealing year-round exposure to endobenthic (within sediments) organisms. Substantial and variable contaminant exposure to epibenthic organisms within the plume footprint was shown by elevated specific conductance measured directly above the sediment interface. Exposure varied daily at times and increased through winter to values representing undiluted plume groundwater. Exposure to pelagic organisms (overlying water) covered a larger area (~50%) due to in-pond circulation. The stream outlet concentrations were stable at approximately 10 times dilution for chloride and saccharin, but were substantially less in summer for ammonium due to in-pond processes. Whereas groundwater contaminants are typically assumed elevated at base flows, the outlet stream contaminant mass discharges to downstream receptors were notably higher in winter than summer, following stream flow patterns. Insights from the present study into the timings and locations of contaminant plume exposure to multiple ecological zones of a pond can provide guidance to contaminated site and aquatic ecosystem managers on improved monitoring, assessment, and remediation protocols. Environ Toxicol Chem 2023;42:1667-1684. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada., (© 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.)
- Published
- 2023
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21. Concise Synthesis of Chiral Tricyclic Lactams by Tandem Dynamic Kinetic Asymmetric Reductive Amination/Lactamization Using Ammonium Salts.
- Author
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Wang J, Shi Y, Wang F, Huang F, Bai ST, Zhao Y, and Zhang X
- Subjects
- Amination, Salts, Catalysis, Lactams, Ammonium Compounds
- Abstract
The atom- and step-efficient synthesis of chiral fused tricyclic lactams from readily available ketoesters using cheap ammonium salts as the nitrogen source is reported. This ruthenium-catalyzed system operates through an efficient tandem dynamic kinetic asymmetric reductive amination (ARA)/lactamization and produces chiral fused tricyclic lactams in high yields with excellent diastereo- and enantioselectivity (up to >99 % ee, >20 : 1 dr and 98 % yield). The robust method was also applied to the concise synthesis of key intermediates in the synthesis of rivastigmine analogues and chiral N-heterocyclic carbene catalysts., (© 2023 Wiley-VCH GmbH.)
- Published
- 2023
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22. Iron-mediated anaerobic ammonium oxidation recorded in the early Archean ferruginous ocean.
- Author
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Pellerin A, Thomazo C, Ader M, Marin-Carbonne J, Alleon J, Vennin E, and Hofmann A
- Subjects
- Geologic Sediments, Anaerobiosis, Nitrates, Nitrogen, Oceans and Seas, Iron metabolism, Ammonium Compounds
- Abstract
The nitrogen isotopic composition of organic matter is controlled by metabolic activity and redox speciation and has therefore largely been used to uncover the early evolution of life and ocean oxygenation. Specifically, positive δ
15 N values found in well-preserved sedimentary rocks are often interpreted as reflecting the stability of a nitrate pool sustained by water column partial oxygenation. This study adds much-needed data to the sparse Paleoarchean record, providing carbon and nitrogen concentrations and isotopic compositions for more than fifty samples from the 3.4 Ga Buck Reef Chert sedimentary deposit (BRC, Barberton Greenstone Belt). In the overall anoxic and ferruginous conditions of the BRC depositional environment, these samples yield positive δ15 N values up to +6.1‰. We argue that without a stable pool of nitrates, these values are best explained by non-quantitative oxidation of ammonium via the Feammox pathway, a metabolic co-cycling between iron and nitrogen through the oxidation of ammonium in the presence of iron oxides. Our data contribute to the understanding of how the nitrogen cycle operated under reducing, anoxic, and ferruginous conditions, which are relevant to most of the Archean. Most importantly, they invite to carefully consider the meaning of positive δ15 N signatures in Archean sediments., (© 2023 The Authors. Geobiology published by John Wiley & Sons Ltd.)- Published
- 2023
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23. Development of Rice Straw-derived Biochar-Bentonite Composite and its Application for in situ Sequestration of Ammonium and Phosphate Ions in the Degraded Mine Soil.
- Author
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Medha I, Chandra S, Bhattacharya J, Samal B, and Vanapalli KR
- Subjects
- Humans, Bentonite, Soil, Phosphates, Charcoal, Ammonium Compounds, Oryza
- Abstract
Nutrient pollution has a diverse impact on the environment and human health. The presence of nutrients, such as ammonium and phosphate, is ubiquitous in the environment due to their extensive use in agricultural land and leaching through non-point sources. In this context, biochar-based composites could play an essential role in improving the soil's nutrient retention capacity. The present study aims to develop bentonite-biochar composites (BNT@BC 400 and 600) and utilize them as an ameliorating material in the coal mine degraded soil to reduce the leaching of ammonium and phosphate ions. The bentonite-biochar composite (BNT@BC 400 and 600) was synthesized using the pristine rice straw-derived biochar using the solvothermal method. The biochar was produced at two different pyrolytic temperatures, 400 °C and 600 °C, and denoted as BC 400 and 600, respectively. Hence, the bentonite-biochar composite was denoted as BNT@BC 400 and 600. The BNT@BC 400 and 600 were characterized using the elemental, proximate, SEM, XRD, and FTIR analysis. Subsequently, the BNT@BC composites were evaluated for the adsorptive removal of NH
4 + and PO4 3- ions using batch adsorption and column leaching studies. In the soil columns, the BNT@BC 400 and 600 were mixed with the soil at two different application rates, viz. 1 and 2.5% (w/w). The leaching characteristics data were fitted using three different fixed-bed models to predict the maximum adsorption capacity of the amended soil columns and the dominant mechanism of adsorption. Results indicated that the BNT@BC 600 showed the maximum adsorption capacity of 33.77 and 64.23 mg g-1 for the adsorption of NH4 + and PO4 3- ions, respectively. The dominant adsorption mechanisms in the aqueous solution were the electrostatic attraction, complexation, ion exchange, and precipitation processes. In the soil columns, the sorption of NH4 + and PO4 3- ions was governed by diffusive mass transfer and electrostatic interaction. Findings of the study indicated that incorporating the BNT@BC composite in the soil can significantly reduce the leaching of the NH4 + and PO4 3- ions and increase the overall soil fertility., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2023
- Full Text
- View/download PDF
24. Surface modification of ammonium polyphosphate-diatomaceous earth composite filler and its application in flame-retardant paper.
- Author
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Sha, Li-Zheng and Chen, Ke-Fu
- Subjects
SURFACE chemistry ,AMMONIUM compounds ,POLYPHOSPHATES ,DIATOMACEOUS earth ,POLYMERIZATION ,FOURIER transform infrared spectroscopy - Abstract
Ammonium polyphosphate (APP)-diatomaceous earth (DE) composite prepared by in situ polymerization was modified with silane coupling agent (KH550) and was applied as filler to prepare flame-retardant paper. Fourier transfer infrared, X-ray diffraction and thermogravimetry were used to characterize the structure and properties of the fillers, and limiting oxygen index (LOI), cone calorimeter and field-emission scanning electron microscope were used to investigate the flame-retardant properties of the filled paper. Results showed that chemical bonds occurred between APP-10 % DE filler and KH550, and APP-10 % DE filler had lower water solubility and better crystallization and thermostability after it was modified with KH550. Paper filled with modified APP-10 % DE filler had higher LOI value and lower heat release rate and mass loss at the same filler loading, and its charred residue collected after cone calorimeter test was more compact and strong. Surface modification of APP-10 % DE filler with KH550 improves its flame-retardant effect on paper. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
25. Developing a practical model for the optimal operation of wastewater treatment plant considering influent characteristics.
- Author
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Nazif S, Forouzanmehr F, and Khatibi Y
- Subjects
- Sewage, Waste Disposal, Fluid methods, Iran, Oxygen, Water Purification, Ammonium Compounds
- Abstract
Wastewater treatment plants (WWTPs) play an important role in protecting the quality of water sources. The optimum operation of WWTPs in response to continuous changes in the characteristics of the influent of the WWTP is very important, and it can improve the quality of the effluent of the WWTP. In this study, an approach for optimal operation of the WWTP has been presented considering the quantitative and qualitative variables of influent. In the proposed method, first, the simulation model of WWTP is developed and calibrated using the recorded data of its influent and effluent characteristics as well as operation conditions. Then, the influent is classified into clusters quantitatively and qualitatively k-means clustering method. In the final step, after determining the effective operation parameters, the AMOEA-MAP optimization algorithm is used to determine the optimal values of operation parameters for each cluster of influents based on its quantitative and qualitative characteristics including flow rate, COD, ammonium, and temperature. The proposed approach was implemented on a WWTP in the South of Tehran, the capital of Iran. Dissolved oxygen (DO) in the aeration tank, waste-activated sludge flow rate (Q
WAS ) and the ratio of the supernatant flow rate of the sludge dewatering unit to the effluent flow rate (Qd /Qe ) were considered as operation parameters affecting the performance of the system in removing pollutants and their optimal values were obtained as DO, 0.25-1.7 mg/l, QWAS , 875-2000 m3 /day, and Qd /Qe , 10-14%. Using this method, i.e., changing system operation conditions based on influent characteristics, has improved the performance of a system in reducing COD, ammonium, and nitrate in the effluent by 11-41, 17-20 and 15-34, respectively., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2023
- Full Text
- View/download PDF
26. Interaction mechanism between nitrogen conversion and the microbial community in the hydrodynamic heterogeneous interaction zone.
- Author
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Duan L, Fan J, Wang Y, Wu Y, Xie C, Ye F, Lv J, Mao M, and Sun Y
- Subjects
- Nitrogen, Hydrodynamics, Denitrification, Nitrates, Water, Ammonium Compounds, Bacillus, Microbiota, Groundwater
- Abstract
To study the inorganic nitrogen in the process of interaction of river and groundwater and the changes in the microbial community, a vertical simulation device was used to simulate groundwater recharge to river water (upwelling) and river water recharge to groundwater (downwelling). The inorganic nitrogen concentrations in the soil and water solution as well as the characteristics of the microbial community were assessed to determine the inorganic nitrogen transformation and microbial community response in the heterogeneous interaction zone under hydrodynamic action, and the interaction mechanism between nitrogen transformation and the microbial community in the interaction zone was revealed. The removal rates of NO
3 - -N in the simulated solution reached 99.1% and 99.3% under the two fluid-groundwater conversion modes, and the prolonged hydraulic retention time (HRT) of the oxidization-reduction layer in the fine clay area and the high organic matter content made the inorganic nitrogen transformation process dominated by microorganisms more complete. The denitrification during upwelling, dominated by denitrifying bacteria in Sphingomonas, Pseudomonas, Bacillus, and Arthrobacter, was stronger than that during downwelling. Dissimilatory nitrate reduction to ammonium (DNRA), controlled by some aerobic bacteria in Pseudomonas, Bacillus, and Desulfovibrio, was more intense in downflow mode than upflow mode., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2023
- Full Text
- View/download PDF
27. Impact of a dam construction on the intertidal environment and free-living nematodes in the Ba Lai, Mekong Estuaries, Vietnam.
- Author
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Quang NX, Yen NTM, Thai TT, Yen NTH, Van Dong N, Hoai PN, Lins L, Vanreusel A, Veettil BK, Hiep ND, Bang HQ, Quan NH, and Prozorova L
- Subjects
- Animals, Estuaries, Environmental Monitoring, Nitrates, Vietnam, Escherichia coli, Phosphorus analysis, Nitrogen analysis, Carbon, Methane, Oxygen, Geologic Sediments chemistry, Water Pollutants, Chemical analysis, Hydrogen Sulfide, Nematoda, Ammonium Compounds
- Abstract
The impact of high siltation and accumulation of organic and waste material in the intertidal of the dammed Ba Lai River in Vietnam as part of the Mekong estuarine system was investigated by means of marine free-living nematodes. Nutrients content (nitrate, ammonium, total phosphorus, total nitrogen), total suspended solids, total organic carbon, coliform, bacteria E. coli, pH, dissolved oxygen, total dissolved solids, methane and hydrogen sulfide concentration, and the nematode communities were characterized in sediment at selected stations along the river above and below the dam. Our results found elevated methane concentrations at the upstream side of the dam while hydrogen sulfide concentrations found to be highest in the downstream side of the dam. Furthermore, methane and hydrogen sulfide concentrations were correlated to nematode community characteristics such as trophic composition densities and genera composition. There was a clear difference between the communities above and below the dam. The discontinuous nematode community distribution indicated that the Ba Lai River is impacted by dam construction. Potentially the high deposition and eutrophication could turn the area into a methane-rich area related to predicted impact on nematodes., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
- Published
- 2022
- Full Text
- View/download PDF
28. Effects of the aeration mode on nitrogen removal in a compact constructed rapid infiltration system for advanced wastewater treatment.
- Author
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Lu X, Gao M, Yang S, Tang D, Yang F, Deng Y, Zhou Y, Wu X, and Zan F
- Subjects
- Biological Oxygen Demand Analysis, Bioreactors microbiology, Carbon, Denitrification, Nitrogen, Oxygen, Phosphorus, Waste Disposal, Fluid, Wastewater chemistry, Ammonium Compounds, Environmental Pollutants, Water Purification
- Abstract
The configuration and the effective operation of constructed rapid infiltration (CRI) systems are of significance for advanced wastewater treatment. In this study, a novel CRI system was developed with a compact structure consisting of two stages, i.e., oxic and anoxic stages. The CRI system was continuously operated for about 140 days under different aeration modes, i.e., tidal flow, continuous aeration, and intermittent aeration. Nitrogen removal was not desirable with tidal flow due to the insufficient oxygen supply in the oxic stage for nitrification, while continuous aeration could achieve good performance for chemical oxygen demand (COD), ammonium, total nitrogen (TN), and total phosphorus (TP) removal. By comparison, the CRI system operated with intermittent aeration was more favorable due to the effective removal ability for pollutants and relatively lower energy demand. The microbial community analysis revealed that Proteobacteria was the dominant phylum in both oxic and anoxic stages of the developed CRI system. Functional microbial groups (Plasticicumulans, Pseudomonas, and Nitrospira in the oxic stage; Thauera, Candidatus_Competibacter, and Dechloromonas in the anoxic stage) were identified for the mediation of carbon, nitrogen, and phosphorus in the system. This study evaluated the feasibility and the optimal aeration mode of the developed CRI system for advanced wastewater treatment, which could satisfy the requirement for the high standard of effluent quality., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2022
- Full Text
- View/download PDF
29. Paper substrate room-temperature phosphorimetry of polyaromatic hydrocarbons enhanced by surface-active agents
- Author
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Winefordner, J
- Published
- 1988
- Full Text
- View/download PDF
30. Effects of pyruvate on primary metabolism and product quality for a high-density perfusion process.
- Author
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Caso S, Aeby M, Jordan M, Guillot R, and Bielser JM
- Subjects
- Animals, Antibodies, Monoclonal metabolism, Bioreactors, CHO Cells, Cricetinae, Cricetulus, Perfusion, Pyruvic Acid, Ammonium Compounds, Batch Cell Culture Techniques
- Abstract
High volumetric productivities can be achieved when perfusion processes are operated at high cell densities. Yet it is fairly challenging to keep high cell density cultures in a steady state over an extended period. Aiming for robust processes, cultures were operated at a constant biomass specific perfusion rate (BSPR) in this study. The cell density was monitored with a capacitance probe and a continuous bleed maintained the targeted viable cell volume. Despite our tightly controlled BSPR, a gradual accumulation of ammonium and changes in cell diameter were observed during the production phase for three different monoclonal antibodies. Although a lot of efforts in media optimization have been made to reduce ammonium in fed-batch process, less examples are known about how media components impact the cellular metabolism and thus the quality of monoclonal antibodies in continuous processes. In this study, we show that a continuous Na-pyruvate feed (2 g/L/day) strongly reduced ammonium production and stabilized fucosylation, sialylation and high mannose content for three different mAbs., (© 2022 Wiley Periodicals LLC.)
- Published
- 2022
- Full Text
- View/download PDF
31. CHROMATOGRAPHY ON PAPER IMPREGNATED WITH ION-EXCHANGE RESINS. VII. ION EXCHANGE WITH ORGANIC SOLVENTS
- Author
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Padiglione, C
- Published
- 1963
- Full Text
- View/download PDF
32. Modeling and multi-objective optimization for ANAMMOX process under COD disturbance using hybrid intelligent algorithm.
- Author
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Xie B, Ma YW, Wan JQ, Wang Y, Yan ZC, Liu L, and Guan ZY
- Subjects
- Algorithms, Anaerobiosis, Biological Oxygen Demand Analysis, Oxidation-Reduction, Planctomycetales growth & development, Support Vector Machine, Ammonium Compounds analysis, Bioreactors, Models, Theoretical, Nitrogen analysis, Wastewater chemistry, Water Purification methods
- Abstract
Anaerobic ammonium oxidation (ANAMMOX) has been regarded as an efficient process to treat nitrogen-containing wastewater. However, the treatment process is not fully understood in terms of reaction mechanisms, process simulation, and control. In this paper, a multi-objective control strategy mixed soft-sensing model (MCSSM) is developed to systematically design the operating variations for multi-objective control by integrating the developed model, a least square support vector machine optimized with principal component analysis (PCA-LSSVM) and non-dominated sorting genetic algorithm-II (NSGA-II). The results revealed that the PCA-LSSVM model is a feasible and efficient tool for predicting the effluent ammonia nitrogen concentration ([Formula: see text]) and the total nitrogen removal concentration (C
TN, rem ) with determination coefficients (R2 ) were 0.997 for [Formula: see text] and 0.989 for CTN, rem , and gives us the reasonable solutions in influent by using NSGA-II. To achieve a better removal effect, the influent pH should be kept between 7.50 and 7.52, the COD/TN ratio is suggested to maintain at 0.15 and the NH4 + -N/NO2 - -N ratio is suggested to maintain at 0.61. The developed MCSSM approach and its general modeling framework have a high potential of applicability and guidance to bioprocess in wastewater treatment, and numerical models can be structured for predicting and optimization and experiments can be conducted for data acquisition and model establishment.- Published
- 2018
- Full Text
- View/download PDF
33. THE CHROMATOGRAPHIC SEPARATION OF RADIOACTIVE ELEMENTS ON PAPER IMPREGNATED WITH MINERAL ION EXCHANGERS
- Author
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Adloff, J
- Published
- 1961
- Full Text
- View/download PDF
34. A Photo-annealing Approach for Building Functional Polymer Layers on Paper.
- Author
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Qian, Qiuping, Wang, Jian, Yan, Feng, and Wang, Yapei
- Subjects
- *
POLYANILINES , *PHOTOTHERMAL conversion , *NEAR infrared radiation , *AMMONIUM compounds , *WETTING , *NANOFIBERS - Abstract
A straightforward photo-annealing approach was developed for building functional polymer layers on paper. Conducting polyaniline with the ability for photothermal conversion can be readily annealed by near-infrared light. The annealed polymers become both insulating and hydrophobic. Selective photo-annealing produces a functional layer with patterned conductive arrays. This material exhibits real-time response to ammonium gas. Complete photo-annealing preserves the porous structure but changes the wettability of the polyaniline-nanofiber film. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. Denitrifying bioreactor microbiome: Understanding pollution swapping and potential for improved performance.
- Author
-
Hartfiel LM, Schaefer A, Howe AC, and Soupir ML
- Subjects
- Bioreactors, Denitrification, Nitrates, Nitrogen, Oxidation-Reduction, Ammonium Compounds, Microbiota
- Abstract
Denitrifying woodchip bioreactors are a best management practice to reduce nitrate-nitrogen (NO
3 -N) loading to surface waters from agricultural subsurface drainage. Their effectiveness has been proven in many studies, although variable results with respect to performance indicators have been observed. This paper serves the purpose of synthesizing the current state of the science in terms of the microbial community, its impact on the consistency of bioreactor performance, and its role in the production of potential harmful by-products including greenhouse gases, sulfate reduction, and methylmercury. Microbial processes other than denitrification have been observed in these bioreactor systems, including dissimilatory nitrate reduction to ammonia (DNRA) and anaerobic ammonium oxidation (anammox). Specific gene targets for denitrification, DNRA, anammox, and the production of harmful by-products are identified from bioreactor studies and other environmentally relevant systems for application in bioreactor studies. Lastly, cellulose depletion has been observed over time via increasing ligno-cellulose indices, therefore, the microbial metabolism of cellulose is an important function for bioreactor performance and management. Future work should draw from the knowledge of soil and wetland ecology to inform the study of bioreactor microbiomes., (© 2021 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)- Published
- 2022
- Full Text
- View/download PDF
36. HIGH-VOLTAGE PAPER ELECTROPHORESIS OF INORGANIC CATIONS. CONDITIONS FOR CATHODIC MIGRATION AND MEASUREMENT OF MIGRATION RATES
- Author
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Gross, D
- Published
- 1963
- Full Text
- View/download PDF
37. ISOLATION AND ANALYSIS OF THE RARE EARTH ELEMENTS BY PAPER CHROMATOGRAPHY. III. THE USE OF TNOA-AMMONIUM NITRATE
- Author
-
Liang, S
- Published
- 1964
38. THE SEPARATION OF IODIDE, IODATE, AND PERIODATE BY MEANS OF PAPER CHROMATOGRAPHY
- Author
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Cvoric, J
- Published
- 1963
39. PAPER CHROMATOGRAPHIC SEPARATION OF CALCIUM, STRONTIUM, BARIUM AND THORIUM
- Author
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Singh, D
- Published
- 1964
40. ON THE SEPARATION OF RARE EARTH ELEMENTS BY MEANS OF REVERSE-PHASE PAPER CHROMATOGRAPHY. I. THE HDEHP-Na$sub 2$SO$sub 4$ SYSTEM
- Author
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Liang, S
- Published
- 1963
41. Metabolic patterns reveal enhanced anammox activity at low nitrogen conditions in the integrated I-ABR.
- Author
-
Pan J, Huo T, Yang H, Li Z, Chen L, Niu Z, Ni S, and Liu S
- Subjects
- Bioreactors, Denitrification, Oxidation-Reduction, Ammonium Compounds, Nitrogen
- Abstract
Substrate concentrations greatly influence bacterial growth and metabolism. However, optimal nitrogen concentrations for anammox bacteria in nitrogen-limited environments remain unclear. Here, we observed enhanced nitrogen metabolism and anabolism of anammox bacteria at low nitrogen conditions. Efficient nitrogen removal was achieved at ammonium and nitrite influent concentration of 30 mg/L under HRT of 1 hr, with an average nitrogen removal rate (NRR) of 0.73 kg N/(m
3 ·day) in I-ABR composed of four compartments. The highest anammox activity of 6.25 mmol N/ (gVSS·hr) was observed in the fourth compartment (C4) with the lowest substrate levels (ammonium and nitrite of 11.6 mg/L and 7 mg/L). This could be resulted from the highest expression level of genes involved in nitrogen metabolism in C4, which was 1.49-1.67 times higher than that in other compartments. Besides, the second compartment (C2) exhibited the most active anabolism at ammonium and nitrite of 17 mg/L and 13 mg/L, respectively, which contributed to the most active amino acid synthesis and thus the highest EPS (1.35 times higher) in C2. This enhanced amino acid auxotrophy between anammox bacteria with heterotrophs, and consequently, heterotrophs thrived and competed for nitrite. These results hint at the potential application of anammox process in micro-polluted water. PRACTITIONER POINTS: High nitrogen removal and efficient biomass retention at low nitrogen concentrations under short HRT was achieved in I-ABR. Optimal concentrations for anammox nitrogen removal and anabolism were discussed under low nitrogen concentrations. More active anabolism contributed to enhanced amino acid synthesis and thus higher EPS contents. Low substrate levels led to enhanced expression of genes involved in nitrogen metabolism and thus high anammox activity., (© 2021 Water Environment Federation.)- Published
- 2021
- Full Text
- View/download PDF
42. Reduced toxicological activity of cigarette smoke by the addition of ammonium magnesium phosphate to the paper of an electrically heated cigarette: Smoke chemistry and in vitro cytotoxicity and genotoxicity
- Author
-
Roemer, E., Stabbert, R., Veltel, D., Müller, B.P., Meisgen, T.J., Schramke, H., Anskeit, E., Elves, R.G., and Fournier, J.A.
- Subjects
- *
AMMONIUM compounds , *PHOSPHATES , *CIGARETTE industry , *CIGARETTES , *AMMONIA , *OXYGEN - Abstract
Abstract: The effects of the addition of ammonium magnesium phosphate (AMP) to the paper of an electrically heated cigarette (EHC) prototype on smoke composition and toxicity were quantified and the underlying mechanisms investigated. Smoke from EHC prototypes with and without AMP and from conventional cigarettes, i.e. the University of Kentucky Standard Reference Cigarette 1R4F and eight American-blend market cigarettes, was compared. Endpoints for comparison were smoke chemistry, where toxic constituents were measured, cytotoxic activity, as measured in murine fibroblasts embryo cells by the Neutral Red Uptake Assay, and genotoxic activity, as measured in bacteria by the Salmonella Reverse Mutation Assay and in murine lymphoma cells by the TK Assay. The addition of AMP to the EHC led to a reduction of toxic substances and toxicological activity of approximately 30% compared to the EHC without AMP. Compared to the conventional cigarettes, the EHC with AMP showed reductions of 75–90%. Smoke from the EHCs generated in nitrogen atmospheres supplemented with different concentrations of ammonia and oxygen was assayed for its in vitro cytotoxicity and genotoxicity. The results indicate that the ammonia released by AMP at the heating site of the EHC is responsible for the reductions in cytotoxicity and mutagenicity for the EHC with AMP compared with the EHC without AMP. Thus, while the EHC approach distinctly reduces toxic smoke constituents compared to conventional cigarettes, the use of AMP in the paper of an EHC leads to further distinct reductions. In the study presented here, in vitro assays were used as quantitative tools to investigate toxicity-related mechanisms. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
43. Amino acids, betaines and related ammonium compounds in Neapolitan limmo, a Mediterranean sweet lime, also known as lemoncetta Locrese.
- Author
-
Cautela D, De Sio F, Balestrieri ML, Casale R, Laratta B, Castaldo D, Pastore A, Servillo L, and DʼOnofrio N
- Subjects
- Fruit chemistry, Fruit and Vegetable Juices analysis, Humans, Taste, Amino Acids analysis, Ammonium Compounds analysis, Betaine analysis, Calcium Compounds chemistry, Oxides chemistry
- Abstract
Background: The so-called 'Neapolitan limmo' or 'lemoncetta Locrese' is an old and now rare Mediterranean sweet lime, similar to lemon but smaller. It is a fruit distinguished from orange, lemon, mandarin, and lime for its sweeter, watery, and non-acidic taste, with a pH between 5.6 and 5.9. No compositional studies are currently available for this citrus fruit. Here we report, for the first time, the distribution in the limmo juice of free amino acids and their main derivatives such as betaines and related ammonium compounds., Results: Seven proteinogenic amino acids (proline, asparagine, serine, aspartic acid, glutamine, alanine, and threonine) and a non-protein amino acid (γ-aminobutyric acid) characterize Neapolitan limmo juice. Proline betaine is the predominant betaine. The data were compared with those of other important citrus juices., Conclusion: The specific 'taste quality' of Neapolitan limmo juice can be attributed to its peculiar composition in amino acids. The species-specific presence of the ammonium compound derivatives of the amino acid proline, with proline betaine as the predominant betaine, characterize the non-acidic varieties of Mediterranean sweet lime. Our study constitutes an important step towards the repopulation of this ancient plant and its exploitation in food industry. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)
- Published
- 2021
- Full Text
- View/download PDF
44. Advances and challenges of mainstream nitrogen removal from municipal wastewater with anammox-based processes.
- Author
-
Ma WJ, Li GF, Huang BC, and Jin RC
- Subjects
- Bioreactors, Denitrification, Nitrogen, Oxidation-Reduction, Ammonium Compounds, Wastewater
- Abstract
Anaerobic ammonium oxidation (anammox) is a novel process of deammonification that exhibits superior ecological and economic potential compared to that of traditional heterotrophic processes. Although this process has been successfully implemented in treating high-strength nitrogen-contaminated wastewater, it still faces many challenges in treating mainstream municipal wastewater. This review aims to provide an overview of the status and challenges of mainstream anammox-based processes. The different configurations and crucial factors are discussed in this review. Finally, the future needs for feasible application are stated. PRACTITIONER POINTS: Factors restricting mainstream application of anammox-based processes are reviewed. Control strategies for selecting and maintaining anammox bacteria are discussed. Recent advances in nitrite production via partial nitrification or denitrification are summarized. Future needs for the feasible application of anammox-based nitrogen removal technology for mainstream municipal wastewater treatment are outlined., (© 2020 Water Environment Federation.)
- Published
- 2020
- Full Text
- View/download PDF
45. Acquisition of rock phosphate by combined application of ammonium fertilizers and Bacillus amyloliquefaciens FZB42 in maize as affected by soil pH.
- Author
-
Mpanga IK, Ludewig U, Dapaah HK, and Neumann G
- Subjects
- Ammonium Compounds analysis, Fertilizers analysis, Hydrogen-Ion Concentration, Plant Roots growth & development, Plant Roots metabolism, Rhizosphere, Zea mays growth & development, Ammonium Compounds metabolism, Bacillus amyloliquefaciens metabolism, Phosphates metabolism, Soil chemistry, Zea mays metabolism
- Abstract
Aims: The use of plant growth-promoting micro-organisms (PGPMs) to improve plant-nutrient acquisition has a long history but reproducibility remains a challenge. Recent findings suggest an important role of suitable inoculant-fertilizer combinations for the expression of PGPM-effects, particularly with respect to nitrogen (N) supply. In face of the well-documented N form effects on rhizosphere pH, this study addressed the impact of ammonium-assisted PGPM-interactions on the acquisition of sparingly soluble calcium-phosphates as affected by soil pH., Methods and Results: The effects of stabilized ammonium fertilization combined with the PGPM inoculant Bacillus amyloliquefaciens FZB42 on the acquisition of rock phosphate in maize were examined on two soils (moderately acidic-pH 5·6 and alkaline-pH 7·8). On the two contrasting soils, FZB42 improved the P status and promoted plant growth by different mechanisms. On the acidic soil, a combination of ammonium-fertilization with FZB42 increased P-acquisition by Rock P solubilization via rhizosphere acidification but P-supply in the noninoculated control was already sufficient to meet the plant demands. By contrast, on the alkaline soil, plant growth-promotion was associated with FZB42-induced root growth stimulation., Conclusion: The results suggest a significant impact of soil pH on performance and the mode of action of PGPM inoculants, to be considered for practical applications., Significance and Impact of the Study: The study advanced existing knowledge on PGPM-assisted P solubilization as affected by different soil properties. The results suggest perspectives for management options to be considered for efficient use of PGPMs in terms of selecting application strategies with compatible PGPM-fertilizer combinations, depending on soil pH conditions., (© 2020 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.)
- Published
- 2020
- Full Text
- View/download PDF
46. Separation of Alkali Metal Cations by Electrochromatography in Paper
- Author
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Strain, H.
- Published
- 1960
- Full Text
- View/download PDF
47. NOTE ON A PAPER ''ISOTOPIC ENRICHMENT OF $sup 14$C BY CHROMATOGRAPHY ON THIN LAYERS.''
- Author
-
Leseticky, L
- Published
- 1966
48. Revealing degradation pathways of soluble and dissolved organic matter in alluvial-lacustrine aquifer systems impacted by high levels of geogenic ammonium.
- Author
-
Xiong Y, Du Y, Liu M, Deng Y, Shi H, Gan Y, and Wang Y
- Subjects
- Geologic Sediments chemistry, Organic Chemicals chemistry, Solubility, Groundwater chemistry, Ammonium Compounds, Water Pollutants, Chemical chemistry
- Abstract
The excessive presence of geogenic ammonium (NH
4 + ) in groundwater poses a global environmental concern, commonly linked to the degradation of nitrogen-containing dissolved organic matter (DOM). However, there is a gap in systematic studies on the combination of soluble organic matter (SOM) in sediments and DOM in groundwater, with few indoor incubation experiments to validate their degradation pathways. This study utilized ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry to analyze the molecular characteristics of DOM and SOM in aquifer systems affected by geogenic NH4 + . Subsequently, indoor incubation experiments spanning up to 140 d were conducted to verify the degradation pathways. The experimental results revealed a two-phase degradation process for both the DOM and SOM. The initial stage was characterized by the degradation of aliphatic compounds (ALC) with the production of polyphenols (PPE) and highly unsaturated compounds (HUC). The second stage was dominated by the degradation of PPE and HUC, accompanied by the re-consumption of some ALC, while more recalcitrant HUC persisted. Notably, the first stage of SOM degradation exceeded that of DOM degradation, indicating that SOM exhibited greater resistance to aging. This phenomenon may be attributed to a wider range of active enzymes in sediments, the rapid replenishment of SOM by organic matter in sediments, or the accelerated degradation of DOM. The experimental results aligned with the molecular characterization of DOM and SOM in actual aquifer systems. It is hypothesized that NH4 + produced through the direct mineralization of SOM may contribute more to the enrichment of NH4 + in groundwater than that produced through the mineralization of DOM. This study is the first to analyze DOM and SOM together in aquifer systems and validate their degradation pathways through incubation experiments, thereby providing novel insights into the enrichment of geogenic NH4 + in groundwater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
49. Organic particles and high pH in food waste anaerobic digestate enhanced NH 4 + adsorption on wood-derived biochar.
- Author
-
Zheng Y, Bolan N, Jenkins SN, and Mickan BS
- Subjects
- Adsorption, Hydrogen-Ion Concentration, Anaerobiosis, Food Loss and Waste, Charcoal chemistry, Wood chemistry, Ammonium Compounds
- Abstract
Biogas residues (i.e., digestate) are rich in NH
4 + that has great agricultural value but environmental risk if not recycled. Biochar can be an effective adsorbent retaining NH4 + from digestate. However, it remains unclear how the unique composition of digestate affects the capacity and mechanisms of NH4 + adsorption on biochar. This study examined the mechanisms and driving factors of NH4 + recovery from digestate containing different molecular-weight organic particles by using wood-derived biochar with or without H2 O2 modification. Four solutions were prepared, including pure NH4 + , synthetic NH4 + with multiple cations mimicking digestate solution, supernatant of digestate with small organic particles and dissolved organic matter, and digestate mixture containing supernatant and large organic particles. The results showed that compared with pure NH4 + solution, the adsorbed NH4 + was 42% lower in the synthetic NH4 + solution with multiple cations but was 2.2 time higher in the supernatant of digestate on two biochars following 48-h adsorption. Modified biochar did not change NH4 + adsorption in pure NH4 + solution despite higher specific surface area than raw biochar, but it increased the adsorption of NH4 + in digestate solutions with high pH (e.g., 4.03 vs. 3.37 mg N g-1 for modified and raw biochar, respectively, in the supernatant of digestate). Compared with the supernatant, the large organic particles in digestate mixture significantly but slightly decreased NH4 + adsorption on modified but not raw biochar. The desorption rate of NH4 + on the biochar was up to 74%-100%, and it was not supressed by the adsorption of organic particles in digestate. The findings here demonstrate the dominant role of electrostatic attraction in NH4 + adsorption, the important role of high pH and organic particles in digestate in facilitating NH4 + adsorption on biochar, and the suitability of the wood-derived biochar in recovering NH4 + from digestate and releasing N for agricultural application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2024
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50. Insights into soil autotrophic ammonium oxidization under microplastics stress: Crossroads of nitrification, comammox, anammox and Feammox.
- Author
-
She Y, Qi X, and Li Z
- Subjects
- Soil Microbiology, Polyesters metabolism, Soil chemistry, Autotrophic Processes, Iron metabolism, Iron chemistry, Polypropylenes metabolism, Anaerobiosis, Oxidation-Reduction, Nitrification, Soil Pollutants metabolism, Ammonium Compounds metabolism, Microplastics metabolism
- Abstract
Microplastics (MPs) are widespread in agroecosystems and profoundly impact soil microbiome and nutrient cycling. However, the effects of MPs on soil autotrophic ammonium oxidization processes, including nitrification, complete ammonium oxidation (comammox), anaerobic ammonium oxidation (anammox), and anaerobic ammonium oxidation coupled to iron reduction (Feammox), remain unclear. These processes are the rate-limiting steps of nitrogen cycling in agroecosystems. Here, our work unveiled that exposures of polyethylene (PE), polypropylene (PP), polylactic acid (PLA), and polybutylene adipate terephthalate (PBAT) MPs significantly modulated ammonium oxidization pathways with distinct type- and dose-dependent effects. Nitrification remained the main contributor (56.4-70.7 %) to soil ammonium removal, followed by comammox (11.7-25.6 %), anammox (5.0-20.2 %) and Feammox (3.3-11.6 %). Compared with conventional nonbiodegradable MPs (i.e., PE and PP), biodegradable MPs (i.e., PLA and PBAT) exhibited more pronounced impacts on soil nutrient conditions and functional microbes, which collectively induced alterations in soil ammonium oxidation. Interestingly, low-dose PLA and PBAT remarkably enhanced the roles of anammox and Feammox in soil ammonium removal, contributing to the mitigation of soil acidification in agroecosystems. This study highlights the diverse responses of ammonium oxidization pathways to MPs, further deepening our understanding of how MPs affect biogeochemical cycling and enriching strategies for agricultural managements amid increasing MPs pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
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