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This paper investigates the technique of biosynthesis of nanoparticles of zinc oxide from the extraction of moringa leaves. Many researchers recognize the use of this method of green culinary technique because it is cost-effective and has no negative impact on the environment; however, this paper focuses on the bacteria chosen for the green synthesis, which was not addressed by many of the researchers. The firmness and reduction of Zn ions in nanoparticles of zinc oxide were analyzed with a UV-visible spectroscope. Its results show that a wide bandgap was observed in the visible region at a wavelength of 350 nanometers. Extraction of moringa leaves serves as a promising agent for the balance of particle size. The result of medical value shows significant antibacterial activity in contrast to the type of pathogenic bacteria Escherichia coli and Staphylococcus aureus. From the XRD results, there are no further peaks that correspond to impurities that are discovered, demonstrating the great purity of the provided results.

Ultraviolet radiation causes damages to the human body, such as skin ageing, skin cancer, and allergies throughout the world. Applying zinc oxide nanoparticles (ZnO NPs) in sunscreen products (like cloths or textiles) to protect human skin by absorbing the ultraviolet radiations that emerged from the sun. The main aim of this study is to investigate both absorbance and transmittance characteristics of the untreated and treated cotton textiles. For ZnO NPs using hydrothermal methods, they were made from Zn(NO3)2·6H2O and NaOH at a constant annealing temperature of 300°C. Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-vis spectroscopy were used to analyze the produced ZnO NPs. From the FT-IR result, ZnO NPs were observed in the region of 400-600 cm-1. Wurtzite hexagonal structure of ZnO NPs with the average crystal size 32 ± 49 nm was observed from XRD results. Flowers in the shape of synthesized ZnO NPs were observed from SEM images. The UV-vis penetration peaks were identified at 264 nm and 376 nm, with energy band gaps of 4.68 and 3.536 eV, respectively. When compared to bulk ZnO, the energy band gap of ZnO NPs was blue-shifted due to the impact of quantum confinement. The peaks in UV-vis absorption were caused by an electronic transition from the valiancy to the conduction bands. The high energy band shows high absorbance of the synthesis sample in the case of 264 nm. The ZnO NPs were manufactured and applied to 100% of raw cotton to impart sunscreen action to both untreated and treated cotton fabrics. The performance of treatment has been evaluated utilizing UV-vis spectroscopy through quantifying ultraviolet protective factors (UPF) and percentage of transmitted (%T) radiations. The treated cotton textiles have 61.50% UPF while 2.65% ultraviolet radiations were transmitted. In other words, untreated cotton textiles have 1.63% UPF while 74.56% ultraviolet radiation was transmitted. Therefore, the treated cotton textiles have excellent protection categories when compared to untreated cotton textiles.

Elemental powders of iron (Fe), molybdenum (Mo), and carbon (C) were mixed in a pot mill to obtain the compositions of C45, C45–1% Mo, and C45–2% Mo steels. They were then compacted and sintered. The sintered preforms had a density of 75% of the theoretical density (TD). Then, the sintered preforms were subjected to densification to obtain the two densities of 80% and 85% TD through forging. The sintered and densified preforms of the alloy steel were subsequently machined to obtain the required wear test specimens. The experiments were conducted on a pin-on-disc tribometer, conforming to ASTM G99 standards, on a rotating EN32 disc. Using Minitab 16 software, dry sliding wear experiments were planned using a L27 orthogonal array. The percentage TD of the specimens (%Theoretical density + %Porosity = 1), percentage Mo addition, load, and sliding velocity were taken as input parameters, and mass loss was the output parameter. It was observed that increasing the density of the alloy steel adversely affects the wear resistance of the alloy steel, and thus the mass loss is increased. The addition of Mo to the C45 steel improves the wear resistance irrespective of density, owing to hard-phase carbides present in the microstructure. Empirical correlations for mass loss with respect to input parameters were developed using regression analysis. The hardness of the alloy steel was directly related to the density of the alloy. Mo addition contributed to an increase in hardness of the alloy steel. It was observed from optical images of the wear pattern that the C45 steel is subjected to uniform wear, as an evenly spread wear track appeared in the images. On the other hand, it was observed that the C45–Mo-alloyed steel exhibited non-uniform wear because of hard-phases present in the microstructure.

A green deposition method of zinc oxide nanoparticles using coffee leaf extraction was successfully prepared. The use of these preparation techniques is accepted by many researchers because it is nonexpensive and simple and has no environmental impact during the operation. The determination and reduction of Zn ions to ZnO NPs were characterized by using a UV-visible spectroscope. The UV-visible spectroscopy result reveals that the large band gap energy is observed in the visible region at the wavelength of 300 nm. X-ray diffraction and SEM analysis confirm that the deposited nanoparticle is highly crystalline with (111), (222), and (100) planes and cubic shape structure. The coffee leaf extraction serves as a reducing agent for stability of the particle length, where its medicinal value outcome showed an important antibacteria of the pathogenic type which appeared on the wound. The present research deals with the green synthesis of ZnO NPs as well as its application in toxicity reduction.

Chitosan is biopolymer of glucosamine residues, nontoxic, biodegradable and friendly to environment and it also helps to enhance crop production due to their bioactivities. The present experiment was conducted to assess the efficacy of chitosan on the growth and yield related attributes of mulberry, Morus sp. with various concentrations such as 25, 50, 75, 100 and 125 ppm. The chitosan was sprayed thrice on 15, 30 and 45 days after pruning (DAP) on the foliage of three different mulberry varieties namely V1, MR2 and G4. The result revealed that, irrespective of varieties, the foliar application of chitosan at 75 ppm significantly increased the biometric as well as yield related attributes of mulberry over other concentrations. Among the three varieties, V1 showed more response to chitosan application than G4 and MR2. At 75 ppm, chitosan showed marked effect on VI variety of mulberry and significantly increased shoot length (170.67 cm), number of shoots per plant (9.03), number of leaves per shoot (29.48), leaf area (220.26 cm2) and leaf area index (2.72) were observed when compared with control. The application of chitosan at 75 ppm significantly enhanced the yield traits namely weight of 100 leaves (448.10 g), leaf shoot ratio (1.45) and leaf yield (14.01 MT/ha/harvest) in V1.

HighlightsGlyphosate sorption using bio-based adsorbents was investigated in this study.Biochars showed poor sorption of glyphosate in comparison to the activated carbons.Total pore volume of bio-based adsorbents played a key role in sorption of glyphosate.Abstract. This study examined the glyphosate sorption ability of different bio-based materials, including biochars and activated carbons synthesized from Douglas fir, kraft lignin, and mixed wood pellets. All the biochars showed poor sorption of glyphosate in comparison to the activated carbons derived from biochars and the commercial powdered activated carbon (PAC) investigated in this study. All the biochar-derived activated carbons produced in the laboratory showed comparable glyphosate sorption in comparison to PAC. The activated carbons synthesized from Douglas fir biomass showed the highest glyphosate sorption among the activated carbons investigated. Langmuir and Freundlich isotherms were used to describe the adsorption kinetics of glyphosate onto activated carbons. Adsorption capacity showed better correlation (R2 = 0.989) with the total pore volume in comparison to the Brunauer-Emmett-Teller (BET) surface area and microporosity. The results of batch desorption tests indicated that the biochar-derived activated carbons and PAC showed >60% glyphosate retention. The results of this study indicate that activated carbons derived from biochars produced with thermochemical conversion processes could effectively sorb herbicide such as glyphosate similarly to commercial activated carbon and could be used either as a replacement for PAC in water treatment plants or for on-site treatment of agricultural runoff water. Keywords: Adsorption, Desorption, Herbicides, Kraft lignin, Model isotherms, Pore volume.

Nanotechnology from titanium dioxide has been deposited, and its application in desalination and water treatment has been investigated by using sol-gel methods. Homogeneously dispersed sphere shapes of titanium dioxide nanoparticles were observed from scanning electron microscope micrographs and decrease in size as aging time increases from 40 min to 60 min. SEM micrographs of highly transparent nanopowders show that they are detected in the visible region from UV/visible and that their red shift around maximum wavelength increases with increasing aging time due to an increase in water quality. The energy band gap of the generated nanosheet has narrowed as the aging time has increased, which is related to the red shift of the absorption spectrum edge in the sheet. The structural behaviors of deposited nanoparticles have also been investigated, which confirms the existence of anatase as well as rutile levels in the liquid phase. The findings of the PL allowed us to determine the total strength of the intensity. This shows that applying photodegradation by a solar absorber could play a vital role in desalination and water treatment.

Comparison of green and chemical precipitation method syntheses of zinc oxide nanoparticles (ZnO NPs) was performed, and antimicrobial properties were investigated. Avocado, mango, and papaya fruit extracts were carried out for the green synthesising methods, while the chemical precipitation method was chosen from chemical synthesis methods. Zinc nitrate was used as a salt precursor, whereas leaf extract was served as a reducing agent for green synthesising methods. In addition, sodium hydroxide, polyvinyl alcohol, and potassium hydroxide were used as reducing agents in the case of chemical precipitation synthesis methods. ZnO NPs were characterised by characterizing techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The antimicrobial activities of prepared nanoparticles were evaluated on Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), and Salmonella typhimurium (S. typhimurium). The particle sizes of the prepared samples which were evaluated by the Scherrer equation were in the range of 11-21 nm for green synthesis, while 30-40 nm for chemical precipitation synthesis methods. Small agglomerations were observed from SEM results of prepared ZnO NPs from both methods. Prepared ZnO NPs were showed strong antimicrobial properties. From the result, the inhibition zone was in the range of 15-24 mm for the green route and 7–15 mm for chemical precipitation methods, where the standard drugs have 25 mm of the zone of inhibition. A green synthesised method of preparing ZnO NPs gives promising antimicrobial properties compared to chemical synthesis and is also eco-friendly and safe compared to the chemical synthesis.

Supplementary data to this article can be found online at https:// doi.org/10.1016/j.jddst.2019.101355., Purpose The scope of this work is the characterization of the behavior of polysaccharides, such as xanthan gum, as matrix-forming agent for the development of sustained release tablets containing nateglinide. Methods Conventional immediate release (IR) and sustained release (SR) tablets were produced by wet granulation and direct compression methodologies, respectively. FTIR analysis demonstrated no interactions between drug and excipients, as the physicochemical characteristics of bulk materials were kept in the formulated tablets. Results Fresh IR and SR tablets exhibited appropriate friability and hardness properties for transport and handling. Formulations composed of xanthan gum showed delayed release properties; while dependent on the polymer concentration, release followed the first order kinetics fitting to Fickian mathematical model. The optimized formulation was tested in six male albino rats for the comparison of the in vivo performance of IR and SR tablets. While oral bioavailability remained similar between both types of tablets, the pharmacokinetic parameters demonstrated the modified release profile of SR i.e. extended half-life (t1/2) and higher maximum time to peak (tmax), and decreased maximum plasma concentration (Cmax) and elimination rate (kel), contributing for longer-term treatments with this drug. Conclusions Sustained release tablets composed of xanthan gum have been successfully developed for the oral delivery of nateglinide., info:eu-repo/semantics/publishedVersion

Gasification tar during a fluidized bed operation impedes syngas utilization in downstream applications. Among tar constituents sampled during biomass gasification, benzene was the most abundant species. Thus, benzene was used as a model compound for chemical looping dry reforming (CLDR) over iron (Fe) and nickel (Ni) metals impregnated on silicon carbide (SiC) in a lab-scale fluidized bed reactor to convert it into hydrogen and carbon monoxide (H2 and CO). A high benzene conversion rate (>90%) was observed at a higher experimental temperature (above 730 °C). Catalytic conversion of benzene using NiFe/SiC catalyst resulted in higher H2 production whereas higher levels of CO were produced with Fe/SiC catalyst at an elevated temperature. Control experiments using an empty bed and SiC bed showed the formation of both the biphenyls and excessive carbon deposits. Air oxidation was also performed for the regeneration of oxygen carrier during the chemical looping operation.

Activated carbon is known to enhance methane formation in anaerobic reactors via interspecies electron transfer between fermentative bacteria and methanogenic archaea. Biochar, a by-product of biomass pyrolysis process, could also perform similar functions due to its conductive properties and the presence of redox active moieties. Hence, this study was conducted to evaluate the effectiveness of different types of activated carbons and biochars on anaerobic digestion. Biochars obtained from canola meal, switchgrass and Ashe juniper were tested for methane production from both glucose and aqueous phase of bio-oil generated via hydrothermal liquefaction of algae. The results suggested that absorbents enhanced methane production. Furthermore, biochars synthesized at intermediate temperatures significantly increased methane yield and reduced the lag time required for methane formation. In addition, the results suggested that the redox active moieties such as quinones and phenazines in biochars are responsible for electron transport, which ultimately enhanced methane production.

Anaerobic digestion of poultry litter is a potentially sustainable means of stabilizing this waste while generating biogas. However, technical challenges remain including seasonality of litter production, low C/N ratios, limited digestibility of bedding, and questions about transformation of nutrients during digestion. This study investigated biogas production and nutrient transformations during anaerobic digestion of poultry litter leachate and whole litter. Use of fresh litter collected from within the house was also compared to waste litter cake that was stored outdoors on the farm. The results showed that litter leachates had higher biomethane potential (0.24–0.30 L/gVS) than whole litter (0.15–0.16 L/gVS) and the insoluble bedding material left after leaching (0.08–0.13 L/gVS). Leachates prepared from waste litter cake had lower uric acid and higher acetic acid concentrations than fresh litter indicating that decomposition had occurred during storage. Consequently, waste litter cake had faster initial biogas production but lower final biogas yields compared to fresh litter. In all reactors, uric and acetic acids were completely consumed during digestion, phosphate levels decreased but ammonium levels increased. The results demonstrate that poultry litter leachate is amenable to digestion despite a low C/N ratio and that the remaining insoluble bedding material has been partially stripped of its nutrients. Moreover, litter can be stored prior to digestion but some losses in biomethane potential should be expected due to decomposition of organics during storage.

Raised serum uric acid, a marker of oxidative stress, is known to increase vascular tone and depress myometrial contractility. A rise in serum uric acid levels has also been reported during labor, warranting its correlation with post-spinal hypotension and uterine tone.Serum UA sample was drawn from enrolled healthy, laboring parturients. Of these, 100 women who required emergency cesarean delivery were re-sampled prior to surgery. Following spinal anesthesia we recorded episodes of hypotension (MAP 80% of baseline), use of vasopressors and supplemental uterotonics. The primary outcome was maternal hyperuricemia (1SD appropriate for gestation age) and its correlation with post-spinal hypotension. Secondary outcomes were total vasopressors used, duration of labor and its effect on uric acid levels, uterine tone and neonatal outcome.Hyperuricemia was observed in 33% of parturients. On comparing with women showing normal uric acid levels, hyperuricemic parturients experienced significantly lower incidence of post-spinal hypotension (45.5% vs. 67.2%; p value = 0.04) and lower vasopressor usage (p value = 0.06). Clinically, an increased use of supplemental uterotonics in these parturients was noted (p = 0.20). The duration of labor had no impact on uric acid levels. Neonatal outcome was unaffected.In healthy, normotensive parturients undergoing emergency cesarean delivery, maternal hyperuricemia is associated with lower incidence of post-spinal hypotension and reduced need of vasopressors. Elevated serum uric acid levels may also be associated with decreased uterine tone, necessitating greater requirement of supplemental uterotonics. However, further prospective trials are needed to strongly establish this association.

A series of three metal complexes of the 3-benzoyl-7-methoxycoumarin ligand have been synthesized and characterized by elemental analyses, molar conductance, Fourier-transform infrared spectroscopy, thermogravimetric analysis, electron paramagnetic resonance, proton nuclear magnetic resonance spectroscopy and cyclic voltammetry techniques. The infra-red spectra of the ligand and its complexes showed that the ligand behaved as a bidentate and confirmed the presence of nitrate ions in the coordination sphere. Thermal stability of the complexes was studied using thermogravimetric and differential thermal analysis, which supported the presence of nitrate ions in these complexes. All complexes exhibited an octahedral geometry around the metal center. The redox property of the metal complexes was studied cyclic voltametrically, which showed that all the complexes exhibited quasi-reversible nature. Antimicrobial studies of these metal complexes and the ligand were conducted against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Aspergillus niger and Candida albicans species. Metal complexes exerted greater antimicrobial activities compared to the ligand. The optimized structure of the zinc complex of coumarin derivative was obtained using DFT/RB3LYP method with 6-311G++G (d,p) basis set. Density functional theory calculations were performed for the determination of geometry structure and vibrational assignments for the zinc complex.

Biological sulfate (SO42−) reduction was examined in anaerobic sequential batch reactors (ASBRs) operated under different hydraulic retention times (HRTs) ranging from 12 to 36 h and COD (Chemical Oxygen Demand)/SO42−) ratios of 2.4, 1.6 and 0.8. Competition between SO42− reducing bacteria (SRBs), methane producing archaea (MPAs) and homoacetogens (HACs) was examined in controls and cultures treated with linoleic acid (LA). The ASBR performance was influenced by the COD/SO42− ratio in control cultures with a SO42− reduction of 87% at a COD/SO42− ratio of 0.8. At a 12 h HRT, in both control and LA treated cultures, greater than 75% SO42− removal was observed under all the conditions examined. In control reactors operating at a 36 h HRT, high levels of MPAs belonging to Methanobacteriales and Methanosarcinales were detected, however, in comparison, under low COD/SO42− ratio and with decreasing HRT conditions, a relative increase in SRBs belonging to Desulfovibrio and Desulfatibacillum was observed. Adding 0.5 g·L−1 LA suppressed Methanobacteriales, while increasing the LA concentration to 1 g·L−1 completely suppressed MPAs with a relative increase in SRBs. HACs belonging to Bacteroidetes were observed in the control and in cultures operated at 12 h HRT with a COD/SO42− ratio of 1.6 and fed 0.5 g·L−1 LA, however, with all other LA levels (0.5 and 1.0 g·L−1) and HRTs (12, 24 and 36 h), HACs were not detected.

Hydrothermal liquefaction (HTL) of nine algae species were performed at two reaction temperatures (280 and 320°C) to compare the effect of their biomass composition on product yields and properties. Results obtained after HTL indicate large variations in terms of bio-oil yields and its properties. The maximum bio-oil yield (66wt%) was obtained at 320°C with a high lipid containing algae Nannochloropsis. The higher heating value of bio-oils ranged from 31 to 36MJ/kg and around 50% of the bio-oils was in the vacuum gas oil range while high lipid containing algae Nannochloropsis contained a significant portion (33-42%) in the diesel range. A predictive relationship between bio-oil yields and biochemical compositions was developed and showed a broad agreement between predictive and experimental yields. The aqueous phases obtained had high amount of TOC (12-43g/L), COD (35-160g/L), TN (1-18g/L), ammonium (0.34-12g/L) and phosphate (0.7-12g/L).

Taguchi statistical design, an orthogonal array (OA) method, was used to study the impact of the COD/SO42− ratio, hydraulic retention time (HRT) and linoleic acid (LA) concentration on sulfate (SO42−) reduction in an anaerobic sequencing batch reactor using glucose as the electron donor. Based on the OA, optimum condition for maximum SO42− reduction was evaluated. Increasing the COD/SO42− ratio and HRT caused decreasing SO42− reduction while increased SO42− reduction was observed with increasing LA concentration (1 g L−1). In control (not fed LA) cultures, higher SO42− reduction (87% ± 3%) was observed at a low COD/SO42− ratio of 0.8. This indicates that increasing SO42− reduction was observed at increasing SO42− loading rates. In general, results from this study reveal that limiting the substrate concentration with high SO42− levels (low COD/SO42− ratio) favors high SO42− removal. Surface plots were used to evaluate the significant interactions between the experimental factors. Accuracy of the model was verified using an analysis of residuals. Optimum conditions for maximum SO42− reduction (97.61%) were observed at a COD/SO42− ratio of 0.8 (level 1), 12 h HRT (level 1) together with 1000 mg L−1 LA addition (level 3). In general, the Taguchi OA provided a useful approach for predicting the percent SO42− reduction in inhibited mixed anaerobic cultures within the factor levels investigated.

Hydrogen (H-2) production using mixed anaerobic cultures often suffers severe yield reduction due to the syntrophic association between H-2 consumers (methanogens and homoacetogens) and H-2 producers (acidogens). The objective of this study was to uncouple the syntrophic association between H-2 producers and consumers by optimizing conditions for minimum H-2 consumption using a Box-Behnken design approach. The factors investigated in this study include temperature, pH and linoleic acid (LA) concentration. A quadratic response surface model was developed to predict the H-2 consumed by mixed anaerobic cultures and the optimum conditions for minimum H-2 consumption were 38 degrees C, pH 5.5 and 2 g L-1 LA. Methanogenesis was inhibited in cultures fed 2 g L-1 LA and maintained at pH 6.0 and 53 degrees C. In comparison, both methanogenesis and homoacetogenesis were inhibited in cultures fed 1-2 g L-1 LA and maintained at a pH of 4.5 (Fig. 2B and 2E and Table 2 Expt. # 1, 2 and 11). Microbial diversity analysis revealed that LA fed cultures was dominated by spore forming Clostridium sp. in addition to Syntrophus aciditrophus. In comparison, control cultures were dominated by Eubacterium sp., Methanocalculus halotolerans and Methanococcoides alaskense. This study described an approach for regulating H-2 consumption in mixed cultures by optimizing process and environmental factors. Understanding the effects of these individual factors and their interaction is important in the full-scale operation of H-2 production facilities. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

In this study, hydrogen (H 2 ) production from the fermentation of steam exploded corn stalk (CS) liquor was statistically optimized using a fractional factorial design approach. The factors under consideration included temperature, pH and hydraulic retention time (HRT). Under optimal conditions at 53 °C, a pH at 4.5 and a 9.5 h HRT, the observed maximum H 2 yield of 98 ± 2 mL g −1 TVS together with negligible CH 4 were similar to the model predicted responses. A flux analysis revealed negligible homoacetogenic activity in cultures at 53 °C and low pH (≤5.5). Both homoacetogenic (R17) and methanogenic (R28 and R29) fluxes accounted for more than 68–90% of H 2 consumption in cultures at low temperatures. The low H 2 yields observed in cultures maintained at 21 °C and 37 °C was associated with high lactate and solvent levels. High H 2 yields in cultures at 53 °C were associated with a higher abundance of Clostrdium sp. and CH 4 production at low temperatures was due to the presence of hydrogenotrophic methanogens ( Methanothermobacter marburgensis and Methanobrevibacter ruminatum ) and aceticlastic methanogens ( Methanosaeta sp. and Methanosarcina sp.). The results obtained from this study (within the factor ranges investigated) indicated that steam exploded CS liquor could be a potential substrate for H 2 production using mixed microbial cultures.

Due to the toxicity effects and endocrine disrupting properties of phenolic compounds, their removal from water and wastewater has gained widespread global attention. In this study, the photocatalytic degradation of phenolic compounds in the presence of titanium dioxide (TiO2) nano-particles and UV light was investigated. A full factorial design consisting of three factors at three levels was used to examine the effect of particle size, temperature and reactant type on the apparent degradation rate constant. The individual effect of TiO2 particle size (5, 10 and 32 nm), temperature (23, 30 and 37 °C) and reactant type (phenol, o-cresol and m-cresol) on the apparent degradation rate constant was determined. A regression model was developed to relate the apparent degradation constant to the various factors. The largest photocatalytic activity was observed at an optimum TiO2 particle size of 10 nm for all reactants. The apparent degradation rate constant trend was as follows: o-cresol > m-cresol > phenol. The ANOVA data indicated no significant interaction between the experimental factors. The lowest activation energy was observed for o-cresol degradation using 5-nm TiO2 particles. A maximum degradation rate constant of 0.0138 min−1 was recorded for o-cresol at 37 °C and a TiO2 particle size of 13 nm at a D-optimality value of approximately 0.98. The response model adequately related the apparent degradation rate constant to the factors within the range of factors under consideration.

The impact of different chemical microbial stressors (2-bromoethanesulfonate (BES), furfural, fish oil, lauric acid (LUA) and linoleic acid (LA)) on the inhibition of mesophilic hydrogen (H-2) consumption was examined in this study. Hydrogen consumption half-life values were used to compare the extent of inhibition by the different microbial stressing agents. A statistical analysis of the percent H-2 consumed using Tukey's analysis revealed the following trend: Control > fish oil = linoleic acid (LA (C18:2)) = furfural > BES > lauric acid (LUA (C12:0). The terminal restriction fragment length polymorphism (T-RLFP) results indicated that aceticlastic methanogens (Methanosaeta sp., Methanosarcina sp.) and hydrogenotrophic methanogens (Methanococcus sp.) were inhibited by the different chemical stressing agents. Cultures fed LUA and LA had a high abundance of Clostridium sp., Clostridium propionicum and Propionibacterium acnes. In comparison, BES and furfural fed cultures contained large fractions of Clostridium sp., Eubacteria sp. and Bacteroides sp. while in the fish oil fed cultures, the dominant organism detected was Eubacteria sp. This study indicated that H-2 consumption was affected by the chemical stressing agent concentration. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Removal of nutrients (phosphorus and nitrogen) as struvite from bio-oil aqueous phase generated via hydrothermal liquefaction of algae was evaluated in this study. Effect of process parameters such as pH, temperature and reaction time on struvite formation was studied. More than 99% of phosphorus and 40-100% ammonium nitrogen were removed under all experimental conditions. X-ray diffraction analysis confirmed the formation of struvite, and the struvite recovered from bio-oil aqueous phase can be used as a slow-release fertilizer. Biogas production from struvite recovered bio-oil aqueous phase showed 3.5 times higher CH4 yield (182±39mL/g COD) as compared to non-struvite recovered aqueous phase. The results from this study indicate that both struvite and methane can be produced from bio-oil aqueous phase.

Hydrothermal liquefaction of wet biomass such as algae is a promising thermochemical process for the production of bio-oil. Bio-oil aqueous phase generated during liquefaction process is rich in complex organics and can be utilized for biogas production following its pre-treatment with granular activated carbon. In our study, use of 30% activated carbon resulted in higher chemical oxygen demand (COD) reduction (53 ± 0.3%) from aqueous phase. Higher CH4 production (84 ± 12 mL/g COD) was also observed in 30% carbon-treated aqueous phase fed cultures, whereas only 32 ± 6 mL CH4/g COD was observed in control (non-carbon treated) cultures. The results from this study indicate that almost 67 ± 0.3% initial COD of aqueous phase can be reduced using a combination of both carbon treatment and biogas production. This study shows that aqueous phase can be utilized for CH4 production.

The effects of lauric (LUA), myristic (MA), palmitic (PA), and a mixture of myristic:palmitic (MA:PA) acids on hydrogen (H-2) production from glucose degradation using anaerobic mixed cultures were assessed at 37 degrees C with an initial pH set at 5.0 and 7.131 mM of each acid. The maximum H-2 yield (2.53 +/- 0.18 mol mol(-1) glucose) was observed in cultures treated with PA. A principal component analysis (PCA) of the by-products and the microbial population data sets detected similarities between the controls and PA treated cultures; however, differences were observed between the controls and PA treated cultures in comparison to the MA and LUA treated cultures. The flux balance analysis (FBA) showed that PA decreased the quantity of H-2 consumed via homoacetogenesis compared to the other LCFAs. The control culture was dominated by Thermoanaerovibrio acidaminovorans (60%), Geobacillus sp. and Eubacterium sp. (28%), while Clostridium sp. was less than 1%. Treatment with PA, MA, MA:PA, or LUA increased the H-2 producers (Clostridium sp. and Bacillus sp.) population by approximately 48, 67, 86, and 86%, respectively. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

In this study, fermentation of a thermally treated simulated organic solid waste into hydrogen (H-2) was examined using a pretreated anaerobic mixed culture. The culture was fed a steam exploded food waste plus paper-cardboard waste blend liquor with and without linoleic acid (LA). The individual and interaction effects of the initial pH, LA concentration and the initial chemical oxygen demand (COD) concentration on H-2 and methane (CH4) production was assessed using a Box-Behnken design (BBD). The BBD model predicted a maximum H-2 yield of 87 mL g(-1) COD or 98 mL H-2 g(-1) VS with 1.6 g L-1 LA, an initial pH of 5.93 and an initial COD of 9.34 g COD L-1. The major microbial populations detected in cultures at pH 5.5 with and without LA included Clostridium sp., Enterococcus asini, Enterococcus faecalis, and Lactobacillus gallinarum. The dendrogram for the 16S rRNA gene T-RFs profiles showed four major groups with a similarity index of 72-75% for Clade III. The major H-2-producing populations were grouped in Cade I with a similarity index range of 55-75%. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

The effects of linoleic acid (LA (C18:2)) and its degradation by-products on hydrogen (H-2) production were examined at 37 degrees C and an initial pH value of 5.0 using granular and flocculated mixed anaerobic cultures from the same source. In the flocculated cultures, the H-2 consumers were inhibited to a greater extent when compared to the granular cultures. The maximum H-2 yields were 2.52 +/- 0.2 and 1.9 +/- 0.2 mol mol(-1) glucose in the flocculated and granular cultures, respectively. The major long chain fatty acids (LCFAs) detected at which H-2 attained a maximum value were LA (750 mg L-1) and myristic acid (MA) (500 mg L-1). Bacteroides sp. dominated the granular cultures whereas Clostridium sp. and Bacillus spp. were the major microorganisms in the flocculated cultures. A flux balance analysis (FBA) revealed that homoacetogens consumed more H-2 in the granular when compared to the flocculated culture. A principal component analyses (PCA) showed the first three principal components accounted for approximately 76% and 68.5% of the total variability for the LA and its degradation by-products and the T-RFLP data sets, respectively. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

In this study, granular and flocculated anaerobic mixed cultures were pretreated using heat, shock loading, acid, alkali, linoleic acid (LA) and 2-bromoethane sulphonic acid (BESA). Under mesophilic conditions (37 degrees C) and an initial pH value of 6.0, higher H-2 yields were observed for the flocculated cultures when compared to the granular cultures. The maximum yield for granular cultures treated acid, BESA or LA were statistically the same. Butyric acid fermentation was dominant in a majority of the treated cultures. The maximum hydrogenase evolution specific activity (ESA) (124 +/- 8 U-e mg VSS-1) at 37 degrees C correlated with the maximum H-2 yield for the LA treated flocculated cultures (1.69 +/- 0.18 mol mol(-1) glucose). The microbial diversity data clearly showed that the low H-2 yield in the granular cultures was due to the lower proportion of H-2 producers. A principle component analysis (PCA) revealed that the LA treated flocculated and granular cultures were grouped together and showed more diversity in comparison to other pretreatment methods. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

This investigation considers the study of pH system in Common effluent treatment plant (CETP). For this purpose, Perundurai Common Effluent Treatment (PCETP) is taken for study. Waste from textile industries is rarely neutral. Certain processes such as reactive dyeing require large quantities of alkali but pre-treatments and some washes can be acidic. It is therefore necessary to adjust the pH in the treatment process to make the wastewater neutral. This is particularly important if biological treatment is being used, as the microbes used in biological treatment require a pH in the range of 6-8 and will be killed by highly acidic or alkali wastewater. In PCETP, the wastewater is mostly alkali wastes (high pH). For this purpose, hydrochloric acid (HCl) is added to maintain the pH value from 7.5 to 7.8 to save the microbes used in biological treatment as well as to reduce the wastage of chemicals.