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Effects of thermally pretreated temperature on bio-hydrogen production from sewage sludge 被引量:20
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作者 XIAO Ben-yi LIU Jun-xin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第1期6-12,共7页
Hydrogen can be obtained by anaerobic fermentation of sewage sludge. Therefore, in this paper the effects of thermally pretreated temperatures on hydrogen production from sewage sludge were investigated under differen... Hydrogen can be obtained by anaerobic fermentation of sewage sludge. Therefore, in this paper the effects of thermally pretreated temperatures on hydrogen production from sewage sludge were investigated under different pre-treatment conditions. In the thermal pretreatment, some microbial matters of sludge were converted into soluble matters from insoluble ones. As a result, the suspended solid(SS) and volatile suspended solid(VSS) of sludge decreased and the concentration of soluble COD(SCOD) increased, including soluble carbohydrates and proteins. The experimental results showed that all of those pretreated sludge could produce hydrogen by anaerobic fermentation and the hydrogen yields under the temperatures of 121℃ and 50℃ were 12.23 ml/g VS(most) and 1.17 ml/g VS (least), respectively. It illuminated that the hydrogen yield of sludge was affected by the thermally pretreated temperatures. Additionally, the endurance of high hydrogen yield depended on the translation of microbial matters and inhibition of methanogens in the sludge. The temperatures of 100℃ and 121℃ (treated time, 30 min) could kill or inhibit completely the methanogens while the others could not. To produce hydrogen and save energy, 100℃ was chosen as the optimal temperature for thermal pretrcatment. The composition changes in liquid phase in the fermentation process were also discussed. The SCOD of sludge increased, which was affected by the pretreatment temperature. The production of volatile fatty acids in the anaerobic fermentation increased with the pretreatment temperature. 展开更多
关键词 anaerobic fermentation hydrogen production sewage sludge thermally pretreated temperature
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Characterization of Energy_Transduction in Thermal Pretreated Chloroplast from Spinach
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作者 彭建新 万常照 +4 位作者 邹永龙 陈根云 钱月琴 袁勤 王国强 《Acta Botanica Sinica》 CSCD 2001年第1期29-35,共7页
Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloropla... Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloroplasts were seriously affected by thermal pretreatment. The results were obtained as following: (1) The rate of cyclic photophosphorylation declined when the pretreatment temperature increased in the range of 25 to 45 degreesC. (2) The thermal pretreatment led to a decrease of the activity of thylakoid membrane-bounded ATPase. (3) Proton uptake of chloroplasts acid the fluorescence quenching of 9-aminoacridine (9-AA) in thylakoid membrane decreased after the thermal pretreatment, but addition of dicyclohexylcarbodiimide (DCCD) could partially restore the fluorescence quenching of 9-AA. (4) Both the rates of fast phase in electrochroism absorption change at 515 nm and the millisecond delayed light emission (ms-DLE) of chloroplast showed a progressive decrease upon raising the temperature of pretreatment. (5) Immunbloting analysis showed that the thermal pretreatment caused the changes of protein content and the electrophoresis mobility of thylakoid membrane-bound ATPase and its alpha -subunit. (6) If the temperature of pretreatment were higher than 33 degreesC, oxygen uptake of PS I -mediated in the samples was rapidly inhibited, but addition of sinapine into the reaction medium could partially restore the ability of oxygen uptake in the samples. These results are briefly discussed in relation to the change of permeability of thylakoid membranes, the dissociation of coupling factor complex as well as accumulation of the radicals in the thylakoid membranes after thermal pretreatment. 展开更多
关键词 Spinacia oleracea CHLOROPLAST thermal pretreatment energy-transduction permeability of thylakoid membranes coupling factor complex
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Conversion of Pretreated Biomass into Levulinic Acid via Continuous Extraction at Atmosphere Pressure
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作者 范明慧 闫立峰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期92-98,I0004,共8页
Conversion of biomass to chemicals or fuels under mild condition is still a challenge. As a platform molecule for chemicals and fuels, levulinic acid (LA) has been prepared by lique-faction of biomass at high pressu... Conversion of biomass to chemicals or fuels under mild condition is still a challenge. As a platform molecule for chemicals and fuels, levulinic acid (LA) has been prepared by lique-faction of biomass at high pressure. In order to carry out the conversion from wheat straw to LA at atmosphere pressure, continuous extraction of the reactive system by an organic solvent with a higher density than that of water was utilized for degradation of pretreated biomass. Yields of LA were measured by means of gas chromatography-mass spectrometry and nuclear magnetic resonance. The results revealed that a maximum yield of 30.66% of LA can be obtained from wheat straw. In addition, the effects of biomass pretreated conditions on the LA conversion have been studied. The study provides a new route to convert biomass to valuable chemicals at atmosphere pressure. 展开更多
关键词 BIOMASS Pretreatment Continuous extraction Levulinic &cid Atmosphere pressure
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Etherification of Alkali-pretreated Sugarcane Bagasse Cellulose in Tetrahydrofuran 被引量:1
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作者 Shiyu Fu Chuanlong Xie 《Paper And Biomaterials》 2020年第3期44-50,61,共8页
Sugarcane bagasse(SCB)is an important by-product in the sugar industry.It is a source of cellulose fibers or cellulose for paper mills and textiles factories.In this study,SCB was ethyl etherified in tetrahydrofuran(T... Sugarcane bagasse(SCB)is an important by-product in the sugar industry.It is a source of cellulose fibers or cellulose for paper mills and textiles factories.In this study,SCB was ethyl etherified in tetrahydrofuran(THF)after alkali pretreatment.The alkali concentration for the pretreatment,the ratio of ethyl bromide(EtBr)to dried SCB in the reaction,reaction time,and temperature were investigated for the etherification of SCB.The ethoxyl content and characterization of the product were determined using headspace gas chromatography(HS-GC),Fourier Transform Infrared(FT-IR)and 13C-NMR spectroscopy,respectively.It was found that SCB was well-etherified with EtBr in alkali-THF.Upon ethylation of SCB,the ethoxyl content of the product was high when the alkali concentration and the ratio of EtBr to dried SCB were controlled from 50%to 75%and 4:1(V/w)to 6:1(V/w),respectively.The reaction occurred optimally when the temperature was controlled below 110℃;above this temperature,the degree of etherification decreased.The thermal stability of ethylated SCB was higher than that of SCB but slightly lower than that of commercial ethyl cellulose.Ethylated SCB has the potential to form composites with many materials because it is soluble in a wide variety of solvents. 展开更多
关键词 sugarcane bagasse alkali pretreatment ETHERIFICATION ethylated SCB cellulose
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Characterization of wet microalgal cells pretreated with steam for lipid extraction
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作者 Wenlu Song Rui Huang +4 位作者 Hao Guo Chunguang Yin Chuanling Wang Jun Cheng Weijuan Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第9期114-120,共7页
Steam pretreatment was employed to disrupt Microalgal cells for lipids extraction.Effects of steam pretreatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM)and tran... Steam pretreatment was employed to disrupt Microalgal cells for lipids extraction.Effects of steam pretreatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Effect of treatment on lipid extraction was also studied.Microalgal cell walls were distorted after steam pretreatment due to the hydrolysis of organic macromolecules contained in cell wall.Maximum curvature was increased from 1.88×10^(-6) m^(-1) to 1.43×10^(-7) m^(-1) after treatment with the steam at 130℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pretreatment time was increased to 60 min.Increased steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130℃and pretreatment time of 60 min.Lipid extracted from wet microalgal was significantly increased(2.1-fold)after pretreatment. 展开更多
关键词 Chlorella pyrenoidosa Steam pretreatment Cell wall disruption Lipids extraction
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Reducing sugars production from pretreated rapeseed straw
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作者 肖弥彰 SHIN Hyun-jae DONG Qiu-hua 《Journal of Chongqing University》 CAS 2012年第4期183-194,共12页
Lignocellulosic biomass, being treated only with ammonia, treated with ammonia and then autoclaved, and treated with white-rot fungi after being mechanically chipped, were carried out to access the effects of lignocel... Lignocellulosic biomass, being treated only with ammonia, treated with ammonia and then autoclaved, and treated with white-rot fungi after being mechanically chipped, were carried out to access the effects of lignocellulose degradation by white-rot fimgi cultured on rapeseed straw. Fourier transform infrared spectroscopic analysis was used to show that the white-rot fungus Bjerkandera sp. strain increase the susceptibility of straw to enzymatic saccharification by modifying the lignin component, revealing the effect of these pretreatments on enzymatic saccharification. Reducing sugar production from straws pretreated by ammonia/mechanical chipping/fungi degradation was 29.80% higher than the samples treated with ammonia/autoclaving, indicating an effective degradation of phenolic compounds. After ammonia pretreatment 41% of the straw was converted to RS (reducing sugars) (glucose 50%). After 5 weeks pretreatment with the white-rot fungus, 54.8% of rapeseed straw was further converted to RS, 74% of which was glucose; while only 12% of the control straw was converted (glucose 42%). The white-rot fungus Bjerkandera sp. strain degraded rapeseed straw preferentially at the early stage (before 20 d), and the degradation selectivity was 0.181 1 (cellulose), 0.364 1 (hemicellulose), and 0.454 8 (lignin), suggesting that removal of the phenolic barriers enhanced reducing sugar yield, and the efficiency of fungal pretreatment was comparable with that after alkali treatment, resulting a higher proportion of glucose in the hydrolysates. 展开更多
关键词 PRETREATMENT reducing sugars white-rot fungi Fourier transform infrared
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Thermal Decomposition of Bamboo Phyllostachys Edulis Pretreated with Ionic Liquids-Water Mixtures
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作者 Qingyue Wang Qiyu Chen Takumi Endo 《Green and Sustainable Chemistry》 2015年第2期55-62,共8页
The ionic liquid (IL)-water mixture pretreated bamboo (Phyllostachys edulis) samples were applied in the research of thermal decomposition. [BMIM]Cl (1-Butyl-3-methylimidazolium chloride)- water and [BMIM]BF4 (1-Butyl... The ionic liquid (IL)-water mixture pretreated bamboo (Phyllostachys edulis) samples were applied in the research of thermal decomposition. [BMIM]Cl (1-Butyl-3-methylimidazolium chloride)- water and [BMIM]BF4 (1-Butyl-3-methylimidazolium tetrafluoroborate)-water were used in pretreatment process. Compositions of the untreated bamboo and pretreated bamboo were compared. The results of X-ray diffraction analysis (XRD) were analyzed to explain the effect of ILs mixture on cellulose crystalline structure. The pretreated cellulose with [BMIM]Cl&#45 water mixture was tend to produce the more gaseous products, which were associated with the decomposition rate. The behavior of more CO and CH4 gaseous products and less tar in the thermal decomposition products could be attributed to ILs-water mixture pretreatment process. The potential and some problems of ILs-water mixture pretreatment method applied in thermal chemical conversion methods were also discussed. 展开更多
关键词 Liquid-Water Mixture BAMBOO PHYLLOSTACHYS EDULIS Thermal Decomposition PRETREATMENT
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Production of Fermentable Sugars from Organosolv Pretreated Cassava Peels
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作者 Afolake Atinuke Olanbiwoninu Sunday Ayodele Odunfa 《Advances in Microbiology》 2015年第2期117-122,共6页
Cassava peels are rich in lignocellulolytic materials which are not readily amenable to enzymatic hydrolysis;hence, there is a need for a suitable pretreatment method that will support enzymatic hydrolysis. This study... Cassava peels are rich in lignocellulolytic materials which are not readily amenable to enzymatic hydrolysis;hence, there is a need for a suitable pretreatment method that will support enzymatic hydrolysis. This study was designed to investigate lignocellulolytic organisms that would effectively support the bioconversion of organosolv pretreated cassava peels to fermentable sugars. Decaying cassava peels were collected into sterile bottles and microorganisms isolated, characterized and screened for lignocellulolytic enzymes production. Optimum temperature, pH and nutrient sources for enzyme production were determined. Organosolv pretreatment was carried out using methanol with varied concentration of catalyst (0.01 - 3 M), reaction time (15 - 60 min) and substrate size. Crude enzymes (cellulase and xylanase) from the isolates were added to the pretreated peels and bioconversion was monitored by measuring the concentration of reducing sugar and calculating the percentage peel hydrolysis. The fermentable sugars produced were quantified using gas chromatography. Pseudomonas fluorescens and Aspergillus terreus were isolated. P. fluorescens produces 2.8 u/mL of crude enzymes optimally at 50°C and pH 8 while A. terreus produces 3.4 u/mL optimally at 40°C, pH 6. Both isolates utilizes CarboxyMethylCellulose (CMC) and yeast extract as their best carbon and nitrogen sources. Highest percentage of peel hydrolysis was 67% for P. fluorescens at 0.01 M and 0.05 M for A. terreus (94%). Highest concentration of fermentable sugar was produced by A. terreus crude enzyme (331.79 mg/L glucose, 45.3 mg/L rhamnose and 46.52 mg/L xylose). P. fluorescens and A. terreus effectively supported the bioconversion of organosolv pretreated cassava peels to fermentable sugars. 展开更多
关键词 CASSAVA Peels LIGNOCELLULOSE Bioconversion ORGANOSOLV PRETREATMENT Fermentable Sugars
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Multi-Scale Structural Studies of Sequential Ionic Liquids and Alkali Pretreated Corn Stover and Sugarcane Bagasse
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作者 Ishwinder Kaur Girish Sahni 《Green and Sustainable Chemistry》 2018年第1期92-114,共23页
The complexity of plant cell walls impedes the conversion of cellulosic biomass to sugars. Pretreatment becomes a necessity to increase the digestibility of biomass. An in-depth understanding of the structure and unde... The complexity of plant cell walls impedes the conversion of cellulosic biomass to sugars. Pretreatment becomes a necessity to increase the digestibility of biomass. An in-depth understanding of the structure and underlying mechanisms governing deconstruction process is important. In the present study, the comprehensive investigation of morphological and structural changes in corn stover and sugarcane bagasse following ionic liquids dissolution and alkaline extraction was done using Fourier transform infrared spectroscopy, Thermogravimetric analysis, Confocal scanning laser microscopy, Atomic force microscopy and Dynamic light scattering studies. Both the substrates were pretreated with ILs 1-ethyl-3-methylimidazolium acetate and 1-butyl-3-methylimidazolium acetate followed by alkaline extraction. The pronounced changes such as lignin, hemicelluloses removal and decreased cellulose crystallinity after the pretreatments lead to the structural transformation of matrix polymers. The enzymatic hydrolysis showed 90% theoretical sugar yield in case of sugarcane bagasse and 80% in corn stover following synergistically combined pretreatments. 展开更多
关键词 PRETREATMENT IONIC Liquids ALKALI Structural Studies HYDROLYSIS
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Effect of Commercial Cellulase Enzymes on Ethanol Production from Pretreated Rice Straw at High Solid Loading
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作者 Teerapatr Srinorakutara Yuttasak Subkaree +2 位作者 Nassapat Boonvitthya Thapparait Kunhanon Nantana Bamrungchue 《Journal of Food Science and Engineering》 2015年第2期67-75,共9页
Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% (w/v) solid. It was found that the best commercial cellulose enzyme was Cellic(R) CTec comparing to Accellerase 1000TM... Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% (w/v) solid. It was found that the best commercial cellulose enzyme was Cellic(R) CTec comparing to Accellerase 1000TM and Accelerase 1500TM. The Cellic(R) CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic(R) CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic(R) CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation (SSF) way at 20% (w/v) solid loading. It could produce 35.76 g/L or 4.6% (v/v) of ethanol concentration and 83.67 L/ton dry matter (DM) of yield. 展开更多
关键词 Rice straw sulfuric acid commercial cellulase PRETREATMENT FERMENTATION ethanol.
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Study on cationic dye adsorption of bio-chars prepared from thermal-alkaline-pretreated sludge
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作者 Zhai Shimin Xiao Benyi +1 位作者 Guo Xuesong Liu Rongzhan 《石化技术》 CAS 2017年第4期33-34,共2页
Sludge bio-char(SC)and thermal-alkaline treated sludge bio-char(TSC)were prepared from municipal sewage sludge(RS)and thermal-alkaline treated sludge sediments(STAS)through fast pyrolysis under nitrogen existence cond... Sludge bio-char(SC)and thermal-alkaline treated sludge bio-char(TSC)were prepared from municipal sewage sludge(RS)and thermal-alkaline treated sludge sediments(STAS)through fast pyrolysis under nitrogen existence condition to remove cationic red X-GRL(A)and cationic yellow X-6G(B)from aqueous solutions.Results of adsorption experiment show that the adsorption capacities of TSC are better than the adsorption capacities of SC.The highest adsorption capacity of 47.65 mg/g for A and 45.41mg/g for B are obtained by TSC in an isotherm experiment at 2.0 g/L dosage and 25°C temperature.TSC adsorption for the two kinds of cationic dyes can be well fitted by pseudo-second-order kinetics model and Langmuir isotherm model. 展开更多
关键词 BIO-CHAR cationic dye ADSORPTION SEWAGE SLUDGE thermal-alkaline pretreatment
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Effect of Water Content on Crystalline Structure of Ionic Liquids Mixture Pretreated Microcrystalline Cellulose (MCC)
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作者 Qingyue Wang Qiyu Chen +2 位作者 Hiroki Niida Naoki Mitsumura Takumi Endo 《Materials Sciences and Applications》 2014年第4期183-192,共10页
Microcrystalline cellulose (MCC) was pretreated by using ionic liquids (ILs)-water mixtures solvent with solid acid catalysts. Different amount of water was considerate as the main variable. The peak shift of pretreat... Microcrystalline cellulose (MCC) was pretreated by using ionic liquids (ILs)-water mixtures solvent with solid acid catalysts. Different amount of water was considerate as the main variable. The peak shift of pretreated sample was determined by FT-IR related to the water content. The XRD was applied to characterize the change in MCC crystalline structure. Thermal decomposition technique was applied to investigate the thermal stability of pretreated MCC. The result indicated that three state of samples were occurred in pretreated MCC sample which was related the amount of water in ILs mixture system. XRD result suggested that the raw sample was distorted and transformed into a less ordered intermediate structure and the smaller crystallite size in lump state sample was obtained which could lead to lower thermal stability. This study revealed the physical chemicals properties, characteristic of molecular structures in MCC using ILs-water mixtures. 展开更多
关键词 MICROCRYSTALLINE Cellulose CRYSTALLITE Structure Ionic Liquids MIXTURE X-Ray DIFFRACTOMETER Pretreatment
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Effect of various aromatic compounds with different functional groups on enzymatic hydrolysis of microcrystalline cellulose and alkaline pretreated wheat straw
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作者 Yufeng Yuan Xinyu Guo +5 位作者 Bo Jiang Wenjuan Wu Tingwei Zhang Michael Sweeney Mehraj Ahmad Yongcan Jin 《Journal of Bioresources and Bioproducts》 EI CSCD 2024年第2期211-221,共11页
Low molecular aromatic compounds are detrimental to the enzymatic hydrolysis of lignocellu-lose.However,the specific role of their functional groups remains unclear.Here,a series of nine aromatic compounds as additive... Low molecular aromatic compounds are detrimental to the enzymatic hydrolysis of lignocellu-lose.However,the specific role of their functional groups remains unclear.Here,a series of nine aromatic compounds as additives were tested to understand their effect on the hydrolysis yield of microcrystalline cellulose(MCC)and alkaline pretreated wheat straw.Based on the results,the inhibition of aldehyde groups on MCC was greater than that of carboxyl groups,whereas for the alkaline pretreated wheat straw case,the inhibitory effect of aldehyde groups was lower than that of carboxyl groups.Increased methoxyl groups of aromatic compounds reduced the inhibitory ef-fect on enzymatic hydrolysis of both substrates.Stronger inhibition of aromatic compounds on MCC hydrolysis was detected in comparison with the alkaline pretreated wheat straw,indicating that the substrate lignin can offset the inhibition to a certain extent.Among all aromatic com-pounds,syringaldehyde with one aldehyde group and two methoxyl groups improved the glucan conversion of the alkaline pretreated wheat straw. 展开更多
关键词 Aromatic compound Functional group Enzymatic hydrolysis Alkaline pretreated wheat straw Microcrystalline cellulose
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Tribological properties of low-temperature time-dependent pretreated graphite for mechanical seal pairs in high-speed turbopump 被引量:1
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作者 Yangyang ZHAO Guoyuan ZHANG +3 位作者 Junqian WANG He WANG Weigang ZHAO Qunfeng ZENG 《Friction》 SCIE EI CAS CSCD 2024年第2期305-318,共14页
The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester,and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretre... The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester,and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear morphology.The results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of graphite.The range of the friction coefficients of pretreated graphite changes from 0.17 to 0.22.With the increase of liquid nitrogen pretreatment time,the wear mechanism of graphite would change from dominated three-body wear to adhesion wear.The experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm^(3)·N^(−1)·m^(−1),and the graphite shows a good low-temperature compatibility. 展开更多
关键词 GRAPHITE low-temperature pretreatment mechanical seal friction and wear
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Lime pretreatment of maize stover and solubilization of pretreated solids by enzymatic hydrolysis and Clostridium thermocellum fermentation
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作者 Guanying Wang Gang Zhang Xiongjun Shao 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第4期288-296,共9页
Lime pretreatment on maize stover was conducted with various pretreatment conditions selected by central composite design.Xylan and lignin contents in pretreated maize stover were relatively constant.Concentration of ... Lime pretreatment on maize stover was conducted with various pretreatment conditions selected by central composite design.Xylan and lignin contents in pretreated maize stover were relatively constant.Concentration of glucose monomer and oligomers decreased while concentration of xylooligomers increased in the pretreatment hydrolysate with increasing pretreatment intensity.The overall carbohydrate recovery was at least 85%for the conditions studied.Xylan removal during pretreatment was found to have a linear correlation with lignin removal.Pretreatment had a higher effect in enhancing carbohydrate solubilization for enzymatic hydrolysis than that for C.thermocellum fermentation.For all the pretreated solids,Clostridium thermocellum fermentation was found to result in much higher carbohydrate solubilization than enzymatic hydrolysis with a cellulase loading of 8 mg/g solids and a xylanase loading of 2 mg/g solids.Carbohydrate solubilization was found to have a linear correlation with lignin removal during lime pretreatment for both enzymatic hydrolysis and C.thermocellum fermentation.Considering the current challenges,this research provides a new idea for the industrial application of lignocellulosic biorefinery. 展开更多
关键词 central composite design lime pretreatment enzymatic hydrolysis clostridium thermocellum carbohydrate solubilization
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Comparison of mesophilic and thermophilic anaerobic digestions of thermal hydrolysis pretreated swine manure: Process performance,microbial communities and energy balance 被引量:2
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作者 Xiaohui Liu Changmin Lee Jae Young Kim 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期222-233,共12页
Anaerobic digestion (AD) of swine manure (SM) commonly shows low biogas output and unsatisfactory economic performance. In this study, thermophilic AD (TAD, 50±1℃) was combined with thermal hydrolysis pretreatme... Anaerobic digestion (AD) of swine manure (SM) commonly shows low biogas output and unsatisfactory economic performance. In this study, thermophilic AD (TAD, 50±1℃) was combined with thermal hydrolysis pretreatment (THP, 170℃/10 bar), to investigate its potential for maximizing biogas yield, securing successful digestion and microbial diversity, as well as improving energy balance. Four lab-scale continuously stirred tank reactors were operated for 300 days and compared with each other, i.e., reactor 1 (raw SM fed in mesophilic AD:RSM-MAD), reactor 2 (THP-treated SM fed in MAD:TSM-MAD), reactor 3 (RSM-TAD),and reactor 4 (TSM-TAD). The results showed that THP was efficient to increase methane production of SM, TSM-TAD mode led to the highest methane yield (129.8±40.5 mL-CH_(4)/gVS/day) among the tests (p <0.05). Although TAD was more likely to induce free ammonia (> 700 mg/L) or volatile fatty acids (> 6000 mg/L) accumulation compared with MAD in start-up phase, TSM-TAD treatment mode behaved a sustainable digestion process in a long-term operation. For TSM-TAD scenario, higher Shannon–Weaver (3.873) and lower Simpson index (0.061) indicated this mode ensured and enlarged the diversity of bacteria communities. Phylum Bathyarchaeota was dominant (59.3%-90.0%) in archaea community,followed by Euryarchaeota in the four reactors. RSM-MAD treatment mode achieved the highest energy output (4.65 GJ/day), TSM-TAD was less effective (-17.38 GJ/day) due to increased energy demands. Thus improving the energetic efficiency of THP units is recommended for the development of TSM-TAD treatment mode. 展开更多
关键词 Thermal hydrolysis pretreatment Digestion temperature Process performances Microbial communities Energy balance
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Anaerobic co-digestion of thermo-alkaline pretreated microalgae and sewage sludge: Methane potential and microbial community 被引量:1
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作者 Jiaqi Fu Bing Yan +2 位作者 Shuanglin Gui Yinxuan Fu Song Xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第5期133-142,共10页
To improve methane production from sewage sludge(SS),co-digestion of SS and microalgae(MA)was studied and the application of thermo-alkaline pretreatment to MA was evaluated.The results showed that thermo-alkaline pre... To improve methane production from sewage sludge(SS),co-digestion of SS and microalgae(MA)was studied and the application of thermo-alkaline pretreatment to MA was evaluated.The results showed that thermo-alkaline pretreatment at 90℃ for 120 min on MA was the optimum pretreatment condition.Furthermore,when the volatile solids(VS)ratio of SS and MA was 1:2,the methane yield reached maximum(368.94 mL/g VS).Fourier transform infrared(FT-IR)and thermogravimetric analysis confirmed the synergetic effects of thermoalkaline pretreated MA on its co-digestion with SS.The analyses of microbial community indicated that Methanobacterium and Methanosarcina were the dominant methanogens during the co-digestion process.However,the relative abundance of Methanosarcina in thermoalkaline pretreated groups was higher compared to unpretreated groups.The microbial community structure might be affected by thermo-alkaline pretreatment rather than by the MA dosage in the co-digestion. 展开更多
关键词 Anaerobic co-digestion Thermo-alkaline pretreatment MICROALGAE Sewage sludge Microbial community
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Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells 被引量:2
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作者 Xin-Xing Wan Xi-Min Hu Kun Xiong 《World Journal of Stem Cells》 SCIE 2024年第2期58-63,共6页
In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cell... In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem Cells.Despite over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be addressed.The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs.As we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole. 展开更多
关键词 Mesenchymal stem cells Inflammatory factor HYPOXIA PRETREATMENT
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Advanced treatment of biologically pretreated coal gasification wastewater by a novel heterogeneous Fenton oxidation process 被引量:15
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作者 Haifeng Zhuang Hongjun Han +3 位作者 Wencheng Ma Baolin Hou Shengyong Jia Qian Zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第7期12-20,共9页
Sewage sludge from a biological wastewater treatment plant was converted into sewage sludge based activated carbon(SBAC) with Zn Cl2 as activation agent, which was used as a support for ferric oxides to form a catal... Sewage sludge from a biological wastewater treatment plant was converted into sewage sludge based activated carbon(SBAC) with Zn Cl2 as activation agent, which was used as a support for ferric oxides to form a catalyst(Fe Ox/SBAC) by a simple impregnation method.The new material was then used to improve the performance of Fenton oxidation of real biologically pretreated coal gasification wastewater(CGW). The results indicated that the prepared Fe Ox/SBAC significantly enhanced the pollutant removal performance in the Fenton process, so that the treated wastewater was more biodegradable and less toxic. The best performance was obtained over a wide p H range from 2 to 7, temperature 30°C, 15 mg/L of H2O2 and 1 g/L of catalyst, and the treated effluent concentrations of COD, total phenols,BOD5 and TOC all met the discharge limits in China. Meanwhile, on the basis of significant inhibition by a radical scavenger in the heterogeneous Fenton process as well as the evolution of FT-IR spectra of pollutant-saturated Fe Ox/BAC with and without H2O2, it was deduced that the catalytic activity was responsible for generating hydroxyl radicals, and a possible reaction pathway and interface mechanism were proposed. Moreover, Fe Ox/SBAC showed superior stability over five successive oxidation runs. Thus, heterogeneous Fenton oxidation of biologically pretreated CGW by Fe Ox/SBAC, with the advantages of being economical, efficient and sustainable, holds promise for engineering application. 展开更多
关键词 Biologically pretreated coal gasification wastewater Heterogeneous Fenton oxidation CATALYST BIODEGRADABILITY MECHANISM
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CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose
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作者 Sen Ma Zheng Li +5 位作者 Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1101-1111,共11页
The conversion of biomass into sugar platform compounds is very important for the biorefinery industry.Pretreatment is essential to the biomass of the sugar platform,however,the lignin obtained by pretreatment,as a ke... The conversion of biomass into sugar platform compounds is very important for the biorefinery industry.Pretreatment is essential to the biomass of the sugar platform,however,the lignin obtained by pretreatment,as a key part of lignocellulose,generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars.In this study,p-TsOH(p-toluenesulfonic acid),DES(Deep eutectic solvent)and CAOSA(cooking with active oxygen and solid alkali)pretreatment ways were used to fraction lignin from bamboo biomass.After CAOSA treatment,the hydrolysis efficiency of the pulp was 95.57%.Moreover,the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system.In this work,the results showed that CAOSA-extracted lignin with lower D(1.31-1.25)had a better adsorption effect on the enzyme protein.p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis.In addition,the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification. 展开更多
关键词 Biomass pretreatment CAOSA Cellulose hydrolysis LIGNIN ENZYME
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