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1.
Sci Rep ; 14(1): 12088, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802402

RESUMO

Nowadays, scientists are currently attempting to lessen the harmful effects of chemicals on the environment. Stability testing identifies how a drug's quality changes over time. The current work suggests a first and sustainable differential pulse voltammetry technique for quantifying difluprednate (DIF) as an anti-inflammatory agent in the presence of its alkaline degradation product (DEG). The optimum conditions for the developed method were investigated with a glassy carbon electrode and a scan rate of 100 mV s-1. The linearity range was 2.0 × 10-7-1.0 × 10-6 M for DIF. DIF was found to undergo alkaline degradation, when refluxed for 8 h using 2.0 M NaOH, and DEG was successfully characterized utilizing IR and MS/MS. The intended approach demonstrated the selectivity for DIF identification in pure, pharmaceutical, and degradation forms. The student's t-test and F value were used to compare the suggested and reported approaches statistically. The results were validated according to ICH requirements. The greenness of the studied approach was evaluated using the Green Analytical Procedure Index and the Analytical Greenness metric. Additionally, the whiteness features of the proposed approach were examined with the recently released red, green, and blue 12 model, and the recommended strategy performed better than the reported approaches in greenness and whiteness.


Assuntos
Técnicas Eletroquímicas , Técnicas Eletroquímicas/métodos , Eletrodos , Hidróxido de Sódio/química , Espectrometria de Massas em Tandem/métodos , Concentração de Íons de Hidrogênio , Química Verde/métodos
2.
Molecules ; 27(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35684351

RESUMO

Results of efficiency of obtaining humic substances (HSs) from peat in traditional alkaline extraction (TAE) and ultrasound-assisted alkaline extraction (UAAE) are presented. The influence of the duration of the process and ultrasound intensity on the efficiency of extraction of humic acids (HAs) and fulvic acids (FAs) extraction was determined. The composition of the fulvic acid fraction was examined depending on the type of eluent used. Fulvic acids were divided into fractions using columns packed with DAX-8 resin. For this process, 0.1 M NaOH and 0.5 M NH3∙H2O were used as eluents. For the quality assessment of specific fulvic acids fractions, spectroscopic methods (UV-Vis and FTIR) were used. Ultrasound had a positive effect on HS extraction efficiency, especially in increasing the amount of a desired hydrophobic fraction of fulvic acids (HPO). However, a negative effect of the excessive prolongation and ultrasound intensity (approximately 400 mW∙cm-2) on the extraction efficiency of HPO eluted with 0.1 M NaOH solution was observed. Using peat as a raw carbon material for the HS extraction process can be used as an alternative industrial application of peat. UAAE may be considered as an alternative method to TAE, which provides a higher efficiency in HS isolation from peat.


Assuntos
Substâncias Húmicas , Solo , Benzopiranos/química , Carbono , Substâncias Húmicas/análise , Hidróxido de Sódio/química , Solo/química , Análise Espectral
3.
Biotechnol Prog ; 38(4): e3257, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35384395

RESUMO

Corn stover, an underutilized agricultural residue, is a promising lignocellulosic feedstock for producing biofuels. To fully utilize it, pretreatment is needed. Typically, pretreatments are rapidly assessed using extracellular enzymes that release sugars from cellulose and hemicellulose. In contrast, this study uses methane-arrested anaerobic digestion (MAAD) to assess pretreatments. Although time consuming, MAAD is a more accurate assessment technique when lignocellulose is employed in the carboxylate platform, a promising approach that utilizes nearly all biomass components. Using recommended pretreatment conditions identified from a previous study, three corn stover pretreatments were compared using MAAD: (1) shock-only, (2) NaOH-only, and (3) shock + NaOH. Air-dried sewage sludge was used as nutrient source. At 100 g/L initial substrate concentration, compared to untreated corn stover, shock-only decreased conversion (amount of biomass digested) by 14%, NaOH-only increased conversion by 82%, and shock + NaOH increased conversion by 104%. Using batch MAAD data, the continuum particle distribution model simulated four-stage countercurrent fermentation. At an industrial non-acid volatile solids (NAVS) concentration of 300 g/Lliq , for both NaOH-only and shock + NaOH, the model predicts total carboxylic acid concentration of about 58 g/L and conversion of about 0.85 g NAVSdigested /g NAVSfed at liquid retention time of 35 days and volatile solid loading rate of 4 g/(Lliq ⋅day). At this long solid residence time, shock is not necessary; however, with short solid residence times, shock acts synergistically to aid NaOH pretreatment. Shock treatment offers a way to reduce pretreatment costs without sacrificing pretreatment efficacy.


Assuntos
Metano , Zea mays , Álcalis/química , Anaerobiose , Biocombustíveis , Esgotos , Hidróxido de Sódio/química , Zea mays/química
4.
Biotechnol Prog ; 38(1): e3217, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34591371

RESUMO

This study investigates digestibility enhancements of lignocellulose from shock pretreatment, alkaline pretreatment, and combination. Shock pretreatment subjects aqueous slurries of lignocellulose to shock waves, which disrupts its structure rendering it more susceptible to hydrolysis. Alkaline pretreatment submerges the biomass in aqueous alkali (NaOH, Ca(OH)2 ), which removes lignin and acetyl groups. As indicators of digestibility, cellulase (CTec3) and hemicellulase (HTec3) were used to saccharify the pretreated corn stover and the resulting filtrate which contains about 10% of the sugars. Shock is most effective when it precedes alkaline pretreatment, presumably because it opens the biomass structure and enhances diffusion of pretreatment chemicals. Lignocellulose digestibility from calcium hydroxide treatment improves significantly with oxygen addition. In contrast, sodium hydroxide is a more potent alkali, and thereby eliminates the need for oxygen to enhance pretreatment. At low hydroxide loadings (<4 g OH- /100 g dry biomass), both NaOH and Ca(OH)2 provide similar increases in digestibility; however, at high hydroxide loadings, NaOH is superior. For animal feed, Ca(OH)2 treatment is recommended, because residual calcium ions are valuable nutrients. In contrast, for methane-arrested anaerobic digestion, NaOH treatment is preferred because NaHCO3 is a stronger buffer. At 50°C, shock pretreatment improves sugar yields at all NaOH loadings. The effect of shock is most pronounced when the no-shock control employed the same soaking-and-drying procedure as the shock treatment. The recommended conditions are shock treatment (5.52 bar [abs] initial H2 /O2 pressure) followed by 50°C alkaline treatment with NaOH loading of 4 g OH- /100 g dry biomass for 1 h.


Assuntos
Álcalis , Zea mays , Álcalis/química , Biomassa , Humanos , Hidrólise , Lignina/química , Oxigênio , Hidróxido de Sódio/química , Zea mays/química
5.
Appl Biochem Biotechnol ; 193(7): 2087-2097, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33599948

RESUMO

A combined severity factor (RCSF) which is usually used to evaluate the effectiveness of hydrothermal pretreatment at above 100 °C had been developed to assess the influence of temperature, time, and alkali loading on pretreatment and enzymatic hydrolysis of lignocellulose. It is not suitable for evaluating alkaline pretreatment effectiveness at lower than 100 °C. According to the reported deducing process, this study modified the expression of [Formula: see text] as [Formula: see text] which is easier and more reasonable to assess the effectiveness of alkaline pretreatment. It showed that RCSF exhibited linear trend with lignin removal, and quadratic curve relation with enzymatic hydrolysis efficiency (EHE) at the same temperature. The EHE of alkali-treated SCB could attain the maximum value at lower RCSF, which indicated that it was not necessary to continuously enhance strength of alkaline pretreatment for improving EHE. Within a certain temperature range, the alkali loading was more important than temperature and time to influence pretreatment effectiveness and EHE. Furthermore, the contribution of temperature, time, and alkali loading to pretreatment cost which was seldom concerned was investigated in this work. The alkali loading contributed more than 70% to the pretreatment cost. This study laid the foundation of further optimizing alkaline pretreatment to reduce cost for its practical application.


Assuntos
Celulase/química , Celulose/química , Saccharum/química , Hidróxido de Sódio/química , Hidrólise
6.
PLoS One ; 15(4): e0231623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294115

RESUMO

Biogenic CBM is an important component of detected CBM, which is formed by coal biodegradation and can be regenerated by anaerobic microorganisms. One of the rate-limiting factors for microbial degradation is the bioavailability of coal molecules, especially for anthracite which is more condense and has higher aromaticity compared with low-rank coal. In this paper, NaOH solution with different concentrations and treating time was employed to pretreat anthracite from Qinshui Basin to alter the coal structure and facilitate the biodegradation. The results showed that the optimal pretreatment conditions were 1.5 M NaOH treating for 12 h, under which the biomethane production was increased by 17.65% compared with untreated coal. The results of FTIR and XRD showed that NaOH pretreatment mainly reduced the multi-substituted aromatics, increased the C-O in alcohols and aromatic ethers and the branching degree of aliphatic chain, and decreased the aromatic ring structure, resulting in the improvement of coal bioavailability and enhancement of biomethane yield. And some organics with potential to generate methane were released to filtrate as revealed by GC-MS. Our results suggested that NaOH was an effective solution for pretreating coal to enhance biogenic methane production, and anthracite after treating with NaOH could be the better substrate for methanogenesis.


Assuntos
Archaea/metabolismo , Reatores Biológicos , Carvão Mineral/microbiologia , Metano/biossíntese , Hidróxido de Sódio/química , Biodegradação Ambiental , Metano/análise , Energia Renovável , Espectroscopia de Infravermelho com Transformada de Fourier , Desenvolvimento Sustentável , Difração de Raios X
7.
Biol Pharm Bull ; 41(2): 208-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29386480

RESUMO

Mume fruit, the Japanese apricot (Prunus mume SIEB. et ZUCC.), is popular in Japan and is mostly consumed in the pickled form called umeboshi. This fruit is known to have anti-microbial properties, but the principal constituents responsible for the antimicrobial properties have not yet been elucidated. We investigated the antimicrobial activities of the phenolic compounds in P. mume against enterobacteria. In this study, growth inhibitory activities were measured as an index of the antibacterial activities. The phenolic compounds were prepared from a byproduct of umeboshi called umesu or umezu (often translated as "mume vinegar"). Umesu or umezu phenolics (UP) contain approximately 20% phenolic compounds with p-coumaric acid as a standard and do not contain citric acid. We observed the inhibitory effects of UP against the growth of some enterobacteria, at a relatively high concentration (1250-5000 µg/mL). Alkali hydrolysates of UP (AHUP) exhibited similar antibacterial activities, but at much lower concentrations of 37.5-300 µg/mL. Since AHUP comprises hydroxycinnamic acids such as caffeic acid, p-coumaric acid, and ferulic acid, the antibacterial activities of each of these acids were examined. Our study shows that the phenolic compounds in P. mume other than citric acid contribute to its antimicrobial activity against enterobacteria in the digestive tract.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Enterobacteriaceae/efeitos dos fármacos , Alimentos em Conserva/análise , Frutas/química , Fenóis/farmacologia , Prunus/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Enterobacteriaceae/crescimento & desenvolvimento , Etnofarmacologia , Indústria de Processamento de Alimentos/economia , Liofilização , Hidrólise/efeitos dos fármacos , Indicadores e Reagentes/química , Resíduos Industriais/análise , Resíduos Industriais/economia , Japão , Medicina Tradicional do Leste Asiático , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Hidróxido de Sódio/química
8.
J Forensic Sci ; 62(5): 1297-1303, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28144942

RESUMO

The treatment of corpses with extremely acid or basic liquids is sometimes performed in criminal contexts. A thorough characterization by chemical analysis may provide further help to macroscopic and microscopic analysis; 63 porcine bone samples were treated with solutions at different pH (1-14) for immersion periods up to 70 days, as well as in extremely acidic sulfuric acid solutions (9 M/18 M) and extremely basic sodium hydroxide. Inductively coupled optical emission spectrometry (ICP-OES)/plasma mass spectrometry (ICP-MS), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray analysis (EDX), X-ray powder diffraction (XRPD), and scanning electron microscopy (SEM) showed that only the sulfuric acid solution 18 M was able to completely dissolve the sample. In addition, chemical analysis allowed to recognize the contact between bone and substances. Hydrated calcium sulfate arose from extreme pH. The possibility of detecting the presence of human material within the residual solution was demonstrated, especially with FT-IR, ICP-OES, and EDX.


Assuntos
Osso e Ossos/química , Osso e Ossos/patologia , Hidróxido de Sódio/química , Ácidos Sulfúricos/química , Animais , Elementos Químicos , Patologia Legal , Concentração de Íons de Hidrogênio , Imersão , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Fosfatos/química , Análise Espectral , Suínos , Difração de Raios X
9.
Bioresour Technol ; 226: 9-17, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27951509

RESUMO

In this work, corn stover subjected to ammonia fiber expansion (AFEX™)1 pretreatment or alkaline pre-extraction followed by hydrogen peroxide post-treatment (AHP pretreatment) were compared for their enzymatic hydrolysis yields over a range of solids loadings, enzymes loadings, and enzyme combinations. Process techno-economic models were compared for cellulosic ethanol production for a biorefinery that handles 2000tons per day of corn stover employing a centralized biorefinery approach with AHP or a de-centralized AFEX pretreatment followed by biomass densification feeding a centralized biorefinery. A techno-economic analysis (TEA) of these scenarios shows that the AFEX process resulted in the highest capital investment but also has the lowest minimum ethanol selling price (MESP) at $2.09/gal, primarily due to good energy integration and an efficient ammonia recovery system. The economics of AHP could be made more competitive if oxidant loadings were reduced and the alkali and sugar losses were also decreased.


Assuntos
Biotecnologia/métodos , Etanol/metabolismo , Zea mays/química , Amônia/química , Biomassa , Biotecnologia/economia , Custos e Análise de Custo , Enzimas/química , Enzimas/metabolismo , Etanol/economia , Peróxido de Hidrogênio/química , Hidrólise , Monossacarídeos/química , Brotos de Planta/química , Brotos de Planta/metabolismo , Hidróxido de Sódio/química , Zea mays/metabolismo
10.
Bioresour Technol ; 216: 503-10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27268435

RESUMO

Cellulase is a prerequisite for the bioconversion of lignocellulosic biomass, but its high cost presents the biggest challenge. In this article, low-cost mixture was produced from glucose through the transglycosylation reaction catalyzed by ß-glucosidase for cellulase overproduction by Trichodema reesei RUT C30. As a result, cellulase titer of 90.3FPU/mL, which was more than 10 folds of that achieved with lactose as inducer, was achieved at 144h. Meanwhile, cellulase productivity was drastically increased to 627.1FPU/L/h, at least 3-5 folds higher than previously reported by the fungal species. The crude enzyme was further tested by hydrolyzing NaOH-pretreated corn stover with 15% solid loading, and 96.6g/L glucose was released with 92.6% sugar yield at 96h and 44.8g/L ethanol was obtained.


Assuntos
Celulase/biossíntese , Glucanos/metabolismo , Microbiologia Industrial/métodos , Trichoderma/enzimologia , Técnicas de Cultura Celular por Lotes , Biomassa , Celulase/metabolismo , Custos e Análise de Custo , Etanol/metabolismo , Glucanos/química , Glucanos/economia , Glucose/economia , Glucose/metabolismo , Glicosilação , Hidrólise , Microbiologia Industrial/economia , Lactose/metabolismo , Brotos de Planta/química , Brotos de Planta/metabolismo , Hidróxido de Sódio/química , Trichoderma/metabolismo , Zea mays/química , Zea mays/metabolismo , beta-Glucosidase/metabolismo
11.
J Environ Manage ; 176: 1-10, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27031295

RESUMO

In this study, ammonia stripping by means of a turbulent mixing process followed by pH neutralization was investigated as a simple and cost-effective ammonia removal technique to treat raw manure digestate. Batch tests conducted using CaO, NaOH and H2O2 to control pH and temperature and combinations thereof showed that sodium hydroxide was the most suitable chemical, as it is easy to handle, minimizes treatment time and costs, does not increase the solid content of the sludge and allows to easily control the stripping process. NaOH dosage mainly depended on buffering capacity rather than on total solid content. The analysis of the ammonia stripping process indicated that ammonia removal was strongly dependent on pH, and ammonia removal rate followed the pseudo-first-order kinetics. Total solid content slightly influenced TAN removal efficiency. When NaOH was applied to treat raw digestate at pH 10 and mean temperature of 23 ± 2 °C, TAN removal efficiency reached 88.7% after 24 h of turbulent mixing stripping, without reaching inhibitory salinity levels. Moreover, pH neutralization with sulfuric acid following the stripping process improved raw digestate dewaterability.


Assuntos
Amônia/isolamento & purificação , Esterco/análise , Eliminação de Resíduos Líquidos/métodos , Compostos de Cálcio/química , Análise Custo-Benefício , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Óxidos/química , Esgotos/química , Hidróxido de Sódio/química , Temperatura
12.
Water Res ; 90: 277-285, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26748205

RESUMO

Oil-in-water (O/W) emulsion is considered to be difficult to treat. In this work, a low-cost multi-layer-structured mullite-titania composite ceramic hollow fiber microfiltration membrane was fabricated and utilized to efficiently remove fine oil droplets from (O/W) emulsion. In order to reduce membrane cost, coal fly ash was effectively recycled for the first time to fabricate mullite hollow fiber with finger-like and sponge-like structures, on which a much more hydrophilic TiO2 layer was further deposited. The morphology, crystalline phase, mechanical and surface properties were characterized in details. The filtration capability of the final composite membrane was assessed by the separation of a 200 mg·L(-1) synthetic (O/W) emulsion. Even with this microfiltration membrane, a TOC removal efficiency of 97% was achieved. Dilute NaOH solution backwashing was used to effectively accomplish membrane regeneration (∼96% flux recovery efficiency). This study is expected to guide an effective way to recycle waste coal fly ash not only to solve its environmental problems but also to produce a high-valued mullite hollow fiber membrane for highly efficient separation application of O/W emulsion with potential simultaneous functions of pure water production and oil resource recovery.


Assuntos
Filtração/métodos , Óleos/química , Eliminação de Resíduos/métodos , Titânio/química , Poluentes Químicos da Água/isolamento & purificação , Água/química , Cerâmica/química , Carvão Mineral , Emulsões , Recuperação e Remediação Ambiental , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Resíduos Industriais , Membranas Artificiais , Prótons , Reciclagem , Análise de Regressão , Hidróxido de Sódio/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Poluentes Químicos da Água/análise , Purificação da Água
13.
Artigo em Inglês | MEDLINE | ID: mdl-26646980

RESUMO

Contamination of groundwater by carcinogenic heavy metal, e.g., lead is an important issue and possibility of using a natural rock, laterite, is explored in this work to mitigate this problem. Treated laterite (TL- prepared using hydrochloric acid and sodium hydroxide) was successfully utilized for this purpose. The adsorbent was characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), and Fourier Transform Infrared Spectroscopy (FTIR) to highlight its physical and chemical properties. Optimized equilibrium conditions were 1 g L(-1) adsorbent concentration, 0.26 mm size and a pH of 7 ± 0.2. Monolayer adsorption capacity of lead on treated laterite was 15 mg/g, 14.5 and 13 mg g(-1) at temperatures of 303 K, 313 K and 323 K, respectively. The adsorption was exothermic and physical in nature. At 303 K, value of effective diffusivity of (De) and mass transfer co-efficient (Kf) of lead onto TL were 6.5 × 10(-10) m(2)/s and 3.3 × 10(-4) m/s, respectively (solved from shrinking core model of adsorption kinetics). Magnesium and sulphate show highest interference effect on the adsorption of lead by TL. Efficacy of the adsorbent has been verified using real-life contaminated groundwater. Thus, this work demonstrates performance of a cost-effective media for lead removal.


Assuntos
Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Água Subterrânea/química , Cinética , Hidróxido de Sódio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água/química , Difração de Raios X
14.
Bioresour Technol ; 197: 495-501, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26369279

RESUMO

Flocculation of microalgae with chitosan, polyacrylamide, Al2(SO4)3, NaOH and HNO3 was evaluated. Their flocculation efficiencies and optimal dosages were discussed. The effects of the flocculants on cells viability were also investigated and the cells were found to be intact during the flocculation process. Moreover, the effects of flocculants on the extractions were evaluated. Lipid content after flocculants treatments showed no significant differences. Carbohydrate content was lower but protein content was higher after NaOH treatment than those after other treatments. Furthermore, the five flocculated media maintained approximate growth yields to that of the fresh medium in microalgal cultivation, indicating the five flocculated media could be recycled, thereby reducing the cost of biodiesel production from microalgae. Finally, economic comparison of the flocculants was made and the cost of using HNO3, including flocculating cells and recycling medium, was found to be the lowest.


Assuntos
Biotecnologia/métodos , Floculação , Microalgas/fisiologia , Resinas Acrílicas/química , Resinas Acrílicas/economia , Resinas Acrílicas/farmacologia , Biocombustíveis , Biotecnologia/economia , Quitosana/química , Quitosana/economia , Quitosana/farmacologia , Custos e Análise de Custo , Meios de Cultura , Metabolismo dos Lipídeos/efeitos dos fármacos , Microalgas/química , Microalgas/efeitos dos fármacos , Ácido Nítrico/química , Ácido Nítrico/economia , Ácido Nítrico/farmacologia , Proteínas de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Reciclagem , Scenedesmus/efeitos dos fármacos , Scenedesmus/fisiologia , Hidróxido de Sódio/química , Hidróxido de Sódio/economia , Hidróxido de Sódio/farmacologia
15.
Lab Chip ; 15(6): 1598-608, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25656508

RESUMO

In this work, we first report a facile, low-cost and high-throughput method for photolithographical fabrication of microfluidic cloth-based analytical devices (µCADs) by simply using a cotton cloth as a substrate material and employing an inexpensive hydrophobic photoresist laboratory-formulated from commercially available reagents, which allows patterning of reproducible hydrophilic-hydrophobic features in the cloth with well-defined and uniform boundaries. Firstly, we evaluated the wicking properties of cotton cloths by testing the wicking rate in the cloth channel, in combination with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses. It is demonstrated that the wicking properties of the cloth microfluidic channel can be improved by soaking the cloth substrate in 20 wt% NaOH solution and by washing the cloth-based microfluidic patterns with 3 wt% SDS solution. Next, we studied the minimum dimensions achievable for the width of the hydrophobic barriers and hydrophilic channels. The results indicate that the smallest width for a desired hydrophobic barrier is designed to be 100 µm and that for a desired hydrophilic channel is designed to be 500 µm. Finally, the high-throughput µCADs prepared using the developed fabrication technique were demonstrated for colorimetric assays of glucose and protein in artificial urine samples. It has been shown that the photolithographically patterned µCADs have potential for a simple, quantitative colorimetric urine test. The combination of cheap cloth and inexpensive high-throughput photolithography enables the development of new types of low-cost cloth-based microfluidic devices, such as "microzone plates" and "gate arrays", which provide new methods to perform biochemical assays or control fluid flow.


Assuntos
Fibra de Algodão , Dispositivos Lab-On-A-Chip , Luz , Impressão/economia , Impressão/métodos , Animais , Bovinos , Colorimetria , Glucose/análise , Interações Hidrofóbicas e Hidrofílicas , Polivinil/química , Soroalbumina Bovina/urina , Dodecilsulfato de Sódio/química , Hidróxido de Sódio/química
16.
Bioresour Technol ; 173: 32-41, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25280111

RESUMO

In this investigation, an effort was made to pretreat surplus waste activated sludge (WAS) inexpensively by a novel combined process involving thermo chemical disperser pretreatment. This pretreatment was found to be efficient at a specific energy (SE) consumption of 3360.94 kJ/kg TS, with the chemical oxygen demand (COD) solubilization of 20%. This was comparatively higher than thermo chemically treated sludge where the solubilization was found to be 15.5% at a specific energy consumption of 10,330 kJ/kg TS respectively. Higher production of volatile fatty acids (VFA) (675 mg/L) in anaerobic fermentation of pretreated WAS indicates better hydrolysis performance. The biogas production potential of sludge pretreated through this combined technique was found to be 0.455 (L/gVS) and comparatively higher than thermo chemically pretreated sludge. Economic investigation provides 90% net energy savings in this combined pretreatment. Therefore, this combined process was considered to be potentially effective and economical in sludge disintegration.


Assuntos
Bactérias Anaeróbias/metabolismo , Metano/metabolismo , Eliminação de Resíduos/métodos , Esgotos/química , Esgotos/microbiologia , Hidróxido de Sódio/química , Águas Residuárias/microbiologia , Análise da Demanda Biológica de Oxigênio , Análise Custo-Benefício , Transferência de Energia , Índia , Metano/isolamento & purificação , Eliminação de Resíduos/economia , Hidróxido de Sódio/economia , Águas Residuárias/economia
17.
PLoS One ; 9(9): e107534, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25222021

RESUMO

The impact of NaOH as a ballast water treatment (BWT) on microbial community diversity was assessed using the 16S rRNA gene based Ion Torrent sequencing with its new 400 base chemistry. Ballast water samples from a Great Lakes ship were collected from the intake and discharge of both control and NaOH (pH 12) treated tanks and were analyzed in duplicates. One set of duplicates was treated with the membrane-impermeable DNA cross-linking reagent propidium mono-azide (PMA) prior to PCR amplification to differentiate between live and dead microorganisms. Ion Torrent sequencing generated nearly 580,000 reads for 31 bar-coded samples and revealed alterations of the microbial community structure in ballast water that had been treated with NaOH. Rarefaction analysis of the Ion Torrent sequencing data showed that BWT using NaOH significantly decreased microbial community diversity relative to control discharge (p<0.001). UniFrac distance based principal coordinate analysis (PCoA) plots and UPGMA tree analysis revealed that NaOH-treated ballast water microbial communities differed from both intake communities and control discharge communities. After NaOH treatment, bacteria from the genus Alishewanella became dominant in the NaOH-treated samples, accounting for <0.5% of the total reads in intake samples but more than 50% of the reads in the treated discharge samples. The only apparent difference in microbial community structure between PMA-processed and non-PMA samples occurred in intake water samples, which exhibited a significantly higher amount of PMA-sensitive cyanobacteria/chloroplast 16S rRNA than their corresponding non-PMA total DNA samples. The community assembly obtained using Ion Torrent sequencing was comparable to that obtained from a subset of samples that were also subjected to 454 pyrosequencing. This study showed the efficacy of alkali ballast water treatment in reducing ballast water microbial diversity and demonstrated the application of new Ion Torrent sequencing techniques to microbial community studies.


Assuntos
Álcalis/química , Bactérias/efeitos dos fármacos , Microbiologia da Água , Purificação da Água , Bactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , RNA Ribossômico 16S/genética , Hidróxido de Sódio/química
18.
J Agric Food Chem ; 62(32): 8120-8, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25090032

RESUMO

An integrated process based on hydrothermal pretreatment (HTP) (i.e., 110-230 °C, 0.5-2.0 h) and alkaline post-treatment (2% NaOH at 90 °C for 2.0 h) has been performed for the production of xylooligosaccharide, lignin, and digestible substrate from sweet sorghum stems. The yield, purity, dissociation mechanisms, structural features, and structural transformations of alkali lignins obtained from the integrated process were investigated. It was found that the HTP process facilitated the subsequent alkaline delignification, releasing lignin with the highest yield (79.3%) and purity from the HTP residue obtained at 190 °C for 0.5 h. All of the results indicated that the cleavage of the ß-O-4 linkages and degradation of ß-ß and ß-5 linkages occurred under the harsh HTP conditions. Depolymerization and condensation reactions simultaneously occurred at higher temperatures (≥ 170 °C). Moreover, the thermostability of lignin was positively related to its molecular weight, but was also affected by the inherent structures, such as ß-O-4 linkages and condensed units. These findings will enhance the understanding of structural transformations of the lignins during the integrated process and maximize the potential utilizations of the lignins in a current biorefinery process.


Assuntos
Biocombustíveis/análise , Cáusticos/química , Conservação de Recursos Energéticos , Lignina/química , Caules de Planta/química , Hidróxido de Sódio/química , Sorghum/química , Biocombustíveis/economia , China , Produtos Agrícolas/química , Temperatura Alta , Hidrólise , Cinética , Lignina/análise , Lignina/isolamento & purificação , Estrutura Molecular , Peso Molecular , Vapor
19.
PLoS One ; 8(10): e76525, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24143192

RESUMO

Fe/Al-rich river sediments that were highly polluted with phosphorus (P) were used in tests to determine the optimum preparation techniques for measuring organic P (Po) using solution (31)P nuclear magnetic resonance spectroscopy ((31)P-NMR). The optimum pre-treatment, extraction time, sediment to solution ratio and sodium hydroxide-ethylenediaminetetraacetic acid (NaOH-EDTA) extractant solution composition were determined. The total P and Po recovery rates were higher from freeze- and air-dried samples than from fresh samples. An extraction time of 16 h was adequate for extracting Po, and a shorter or longer extraction time led to lower recoveries of total P and Po, or led to the degradation of Po. An ideal P recovery rate and good-quality NMR spectra were obtained at a sediment:solution ratio of 1:10, showing that this ratio is ideal for extracting Po. An extractant solution of 0.25 M NaOH and 50 mM EDTA was found to be more appropriate than either NaOH on its own, or a more concentrated NaOH-EDTA mixture for (31)P-NMR analysis, as this combination minimized interference from paramagnetic ions and was appropriate for the detected range of Po concentrations. The most appropriate preparation method for Po analysis, therefore, was to extract the freeze-dried and ground sediment sample with a 0.25 M NaOH and 50 mM EDTA solution at a sediment:solution ratio of 1:10, for 16 h, by shaking. As lyophilization of the NaOH-EDTA extracts proved to be an optimal pre-concentration method for Po analysis in the river sediment, the extract was lyophilized as soon as possible, and analyzed by (31)P-NMR.


Assuntos
Alumínio/química , Métodos Analíticos de Preparação de Amostras/métodos , Sedimentos Geológicos/química , Ferro/química , Compostos Orgânicos/análise , Fósforo/química , Rios/química , Ácido Edético/química , Espectroscopia de Ressonância Magnética , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação , Hidróxido de Sódio/química , Soluções , Fatores de Tempo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
20.
J Hazard Mater ; 262: 870-7, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24140539

RESUMO

In the present study, alkaline pretreatment was applied for the enhanced laccase production from rice straw. Various process parameters including sodium hydroxide concentration, pH and fermentation temperature were optimized via response surface methodology (RSM) with a Box-Behnken design (BBD). Through regression analysis, it was found that laccase activity was well fitted by a quadratic polynomial equation (R(2)=0.998, Adj R(2)=0.995), and the fermentation temperature was the most significant factor influencing laccase activity. The optimized process conditions found were NaOH concentration of 0.39 mol L(-1), pH 3.12 and temperature 25.43 °C, under which laccase activity reached 142,198 ± 3586 U L(-1). Further studies were carried out to probe different dyes decolorization ability of laccase produced by Aspergillus fumigatus, A. fumigatus pellets and whole fermentation broth (WFB) using sodium hydroxide pretreated rice straw as sole carbon source. Results showed that pure laccase demonstrate limited decolorization ability to all the studied dyes, while crude laccase, A. fumigatus pellets and WFB exhibit significant decolorization ability to all the studied dyes with WFB being the most excellent one. Effectiveness of degradation was confirmed by uv-vis and phytotoxicity studies, which indicated that A. fumigatus transformed the dyes into non-toxic metabolites.


Assuntos
Aspergillus fumigatus/enzimologia , Corantes/química , Lacase/química , Biodegradação Ambiental , Reatores Biológicos , Carbono/química , Fermentação , Concentração de Íons de Hidrogênio , Oryza/enzimologia , Oryza/microbiologia , Análise de Regressão , Hidróxido de Sódio/química , Espectrofotometria , Propriedades de Superfície , Temperatura , Raios Ultravioleta , Poluentes Químicos da Água/análise , Purificação da Água/economia , Purificação da Água/métodos
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