期刊文献+
共找到491篇文章
< 1 2 25 >
每页显示 20 50 100
Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells 被引量:2
1
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
下载PDF
Cellulosic ethanol and its co-products from different substrates,pretreatments,microorganisms and bioprocesses:A review 被引量:1
2
作者 Fabiano Avelino Goncalves Eliana J.Sanjinez-Argandona Gustavo Graciano Fonseca 《Natural Science》 2013年第5期624-630,共7页
Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of ... Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of cellulosic ethanol and its co-products. Their production still pose some difficulties in terms of pretreatment, the high cost of enzymes for substrate hydrolysis, the formation of inhibitory compounds in the hydrolyzate, the lack of efficient and viable microorganisms for industrial fermentation of hexose and pentose among others. The solution or minimization of these difficulties may lead to numerous socio-environmental, political, and economic advantages for cellulosic ethanol production. This paper highlights the potential of different substrates, pretreatments, microorganisms and bioprocesses for cellulosic ethanol production. 展开更多
关键词 Cellulosic Ethanol pretreatments FERMENTATION
下载PDF
Effect of Different Pretreatments on Explosion Puffing Drying of Hami Melon at Modified Temperature and Pressure in Xinjiang 被引量:2
3
作者 Wenting JIA Hui YANG +2 位作者 Hongbin WU Hong WU Xinwen JIN 《Asian Agricultural Research》 2016年第9期64-66,70,共4页
This paper studies the influence of three different pretreatments( blanching,citric acid soaking,and Na Cl soaking) on the moisture content,degree of puffing,color,hardness and crispness of Hami melon under explosion ... This paper studies the influence of three different pretreatments( blanching,citric acid soaking,and Na Cl soaking) on the moisture content,degree of puffing,color,hardness and crispness of Hami melon under explosion puffing drying at modified temperature and pressure in Xinjiang. The results show that using 60 s blanching pretreatment can help to reduce the moisture content of puffed product while maintaining product color; 2. 5% citric acid pretreatment can make products maintain high degree of puffing and crispness,but reduce product color; 2%Na Cl penetrating fluid plays a significant role in maintaining product color,while maintaining crispness. 展开更多
关键词 PRETREATMENT XINJIANG Hami melon Modified temperature and pressure
下载PDF
Nanostructural Evolution of Sugarcane Rind and Pith Submitted to Hydrothermal Pretreatments
4
作者 Marcelo M.Oliveira Antonio A.S.Curvelo Carlos Driemeier 《Journal of Renewable Materials》 SCIE 2018年第2期152-159,共8页
Lignocellulose conversion into cellulosic ethanol and coproducts starts with a pretreatment step.Most current industrial plants of cellulosic ethanol use thermochemical pretreatments under hydrothermal conditions,with... Lignocellulose conversion into cellulosic ethanol and coproducts starts with a pretreatment step.Most current industrial plants of cellulosic ethanol use thermochemical pretreatments under hydrothermal conditions,with or without addition of acid catalyst.Such pretreatments modify biomass chemistry and morphology,particularly at the nanoscale.In this work,we use X-ray diffraction,dynamic vapor sorption and calorimetric thermoporometry to investigate the biomass nanostructural changes promoted by hydrothermal conditions.We compare and differentiate the rind and pith fractions of sugarcane stalks in order to contribute to the understanding of rind-pith contrasting recalcitrance.Moreover,for both cane fractions our results point consistently to cellulose co-crystallization,lignin aggregation,and opening of nanoscale pores as the main nanostructural phenomena occurring during hydrothermal treatments. 展开更多
关键词 Cellulose BAGASSE SUGARCANE cellulosic ethanol PRETREATMENT
下载PDF
Effect of Different Pretreatments on Solubility of Hemp Fibers in Ionic Liquids
5
作者 ZHONG Zhili ZHANG Xiao +2 位作者 ZHU Min WAN Jia PANG Yu 《Journal of Donghua University(English Edition)》 EI CAS 2018年第1期52-57,共6页
Hemp fibers were treated with different pretreatments before being put into ionic liquid dissolved systems. NaOH,HCI,N,N-dimethylacetamide( DMAc) solution and ultrasonic were utilized to activate fibers. Scanning el... Hemp fibers were treated with different pretreatments before being put into ionic liquid dissolved systems. NaOH,HCI,N,N-dimethylacetamide( DMAc) solution and ultrasonic were utilized to activate fibers. Scanning electron microscopy( SEM),Fourier transform infrared spectroscopy( FTIR) and X-ray diffraction( XRD) were used to analyze the morphological and molecular structures of the fiber before and after activation for the comparative analysis. The pretreated fibers were dissolved and the dissolving process of fibers were observed until they were dissolved completely. Experimental studies found that NaOH solution made fibers crystal form change from cellulose Ⅰ to cellulose Ⅱ,and others didn't have this kind of change. By comparison,fibers treated by DMAc solution worked best, various methods which affected solubility could be sorted roughly as follows: DMAc &gt; ultrasonic &gt;HCI &gt; NaOH &gt; untreated. 展开更多
关键词 hemp fiber ionic liquids PRETREATMENT SOLUTION
下载PDF
Combination of Pretreatments with Acetic Acid and Sodium Methoxide for Efficient Digoxin Preparation from Digitalis Glycosides in Digitalis lanata Leaves
6
作者 Yasuhiko Higashi Yukari Ikeda Youichi Fujii 《Pharmacology & Pharmacy》 2016年第5期200-207,共8页
We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to dete... We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, with the aim of maximizing the yield of digoxin. Leaves were extracted with 50% methanol, followed by clean-up on a Sep-Pak C18 cartridge prior to HPLC analysis. The amounts of lanatoside C, digoxin and α-acetyldigoxin per 100 mg of the leaves without pretreatment were 115.6, 7.45 and 23.8 μg, respectively (deslanoside was not detected). Pretreatment with acetic acid, which activated deglucosylation mediated by digilanidase present in the leaves, increased the amounts of digoxin and α-acetyldigoxin, while lanatoside C and deslanoside were not detected. Pretreatment with sodium methoxide, which hydrolyzed lanatoside C to deslanoside, increased the yields of deslanoside and digoxin, while lanatoside C and α-acetyldigoxin were not detected. The combination of both pretreatments afforded only digoxin in a yield of 115.1 μg/100 mg leaves. Use of the combined pretreatments appears to be effective for maximizing the yield of digoxin from the leaves. 展开更多
关键词 DIGOXIN Lanatoside C α-Acetyldigoxin Deslanoside HPLC Digitalis lanata PRETREATMENT
下载PDF
Regulating microstructure and mechanical property of dissimilar joints by pretreatments of S31042 steel and Ni3Al-based superalloy bonding substrates
7
作者 Yuan-yi Peng Chong Li +2 位作者 Qian-ying Guo Hui-jun Li Yong-chang Liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第11期2328-2339,共12页
For the bonding couple of S31042 steel and Ni3Al-based superalloy,joint microstructure regulation plays a pivotal role in improving joint performance.Different pretreatment approaches including solution and cold rolli... For the bonding couple of S31042 steel and Ni3Al-based superalloy,joint microstructure regulation plays a pivotal role in improving joint performance.Different pretreatment approaches including solution and cold rolling treatments were severally applied to the two substrates before vacuum diffusion bonding.Cold rolling treatment in S31042 steel substrate before bonding promoted the coarsening and precipitation behaviors of large amounts of Z(NbCrN)phases during the bonding process so that the AlN phase decreased in the joint area because of the consumption of N atom in the Z phase.And solution treatment for Ni3Al-based superalloy increased the grain boundary mobility and led to the occurrence of dynamic recrystallization in the diffusion area of the joint by reducing segregation and homogenizing the microstructure within the substrate.As a result,the bonded sample with two substrates that are pretreated exhibited a better tensile strength and elongation at 700℃. 展开更多
关键词 Ni3Al-based superalloy STEEL Joint Pretreatment Diffusion bonding
原文传递
Anaerobic digestion of sludge by different pretreatments:Changes of amino acids and microbial community 被引量:2
8
作者 Keke Xiao Zecong Yu +7 位作者 Kangyue Pei Mei Sun Yuwei Zhu Sha Liang Huijie Hou Bingchuan Liu Jingping Hu Jiakuan Yang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2022年第2期109-123,共15页
Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of... Many studies have investigated the effects of different pretreatments on the performance of anaerobic digestion of sludge.However,the detailed changes of dissolved organic nitrogen,particularly the release behavior of proteins and the byproducts of protein hydrolysis-amino acids,are rarely known during anaerobic digestion of sludge by different pretreatments.Here we quantified the changes of three types of proteins and 17 types of amino acids in sludge samples solubilized by ultrasonic,thermal,and acid/alkaline pretreatments and their transformation during anaerobic digestion of sludge.Tryptophan protein,aromatic protein I,aromatic protein II,and cysteine were identified as the key dissolved organic nitrogen responsible for methane production during anaerobic digestion of sludge,regardless of the different pretreatment methods.Different from the depletion of other amino acids,cysteine was resistant to degradation after an incubation period of 30 days in all sludge samples.Meanwhile,the“cysteine and methionine metabolism(K00270)”was absent in all sludge samples by identifying 6755 Kyoto Encyclopedia of Genes and Genomes assignments of genes hits.Cysteine contributed to the generation of methane and the degradation of acetic,propionic,and n-butyric acids through decreasing oxidation-reduction potential and enhancing biomass activity.This study provided an alternative strategy to enhance anaerobic digestion of sludge through in situ production of cysteine. 展开更多
关键词 Sludge pretreatments Dissolved organic nitrogen Proteins Amino acids Structural equation model Metagenomic sequencing analysis
原文传递
CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose
9
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
下载PDF
Role of tannin pretreatment in flotation separation of magnesite and dolomite
10
作者 Xiufeng Gong Jin Yao +5 位作者 Jun Guo Bin Yang Haoran Sun Wanzhong Yin Yulian Wang Yafeng Fu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期452-461,共10页
Flotation separation of magnesite and its calcium-containing carbonate minerals is a difficult problem.Recently,new regulat-ors have been proposed for magnesite flotation decalcification,although traditional regulator... Flotation separation of magnesite and its calcium-containing carbonate minerals is a difficult problem.Recently,new regulat-ors have been proposed for magnesite flotation decalcification,although traditional regulators such as tannin,water glass,sodium carbon-ate,and sodium hexametaphosphate are more widely used in industry.However,they are rarely used as the main regulators in research because they perform poorly in magnesite and dolomite single-mineral flotation tests.Inspired by the limonite presedimentation method and the addition of a regulator to magnesite slurry mixing,we used a tannin pretreatment method for separating magnesite and dolomite.Microflotation experiments confirmed that the tannin pretreatment method selectively and largely reduces the flotation recovery rate of dolomite without affecting the flotation recovery rate of magnesite.Moreover,the contact angles of the tannin-pretreated magnesite and dolomite increased and decreased,respectively,in the presence of NaOl.Zeta potential and Fourier transform infrared analyses showed that the tannin pretreatment method efficiently hinders NaOl adsorption on the dolomite surface but does not affect NaOl adsorption on the magnesite surface.X-ray photoelectron spectroscopy and density functional theory calculations confirmed that tannin interacts more strongly with dolomite than with magnesite. 展开更多
关键词 tannin pretreatment selective inhibition flotation separation MAGNESITE DOLOMITE
下载PDF
预处理技术--家庭生物废弃物处理过程中的微塑料制造者
11
作者 Tian Hu Fan Lü +4 位作者 Zhan Yang Zhenchao Shi Yicheng Yang Hua Zhang Pinjing He 《Engineering》 SCIE EI CAS CSCD 2024年第1期116-126,共11页
Mechanical pretreatment is an indispensable process in biological treatment plants that remove plastics and other impurities from household biogenic waste(HBW).However,the imperfect separation of plastics in these pre... Mechanical pretreatment is an indispensable process in biological treatment plants that remove plastics and other impurities from household biogenic waste(HBW).However,the imperfect separation of plastics in these pretreatment methods has raised concerns that they pose a secondary formation risk for microplastics(MPs).To validate this presumption,herein,quantities and properties of plastic debris and MPs larger than 50 μm were examined in the full chain of three different pretreatment methods in six plants.These facilities received HBW with or without prior depackaging at the source.The key points in the secondary formation of MPs were identified.Moreover,flux estimates of MPs were released,and an analysis of MPs sources was provided to develop an overview of their fate in HBW pretreatment.Pretreated output can contain a maximum of(1673±279) to(3198±263) MP particles per kilogram of wet weight(particles·kg^(-1)ww) for those undepackaged at source,and secondary MPs formation is primarily attributed to biomass crushers,biohydrolysis reactors,and rough shredders.Comparatively,HBW depackaged at the source can greatly reduce MPs by 8%-72%,regardless of pretreatment processes.Before pretreatment,4.6-205.6 million MP particles were present in 100 tonnes of HBW.MPs are produced at a rate of 741.11-33124.22 billion MP particles annually in anaerobic digester feedstock(ADF).This study demonstrated that HBW pretreatment is a competitive source of MPs and emphasized the importance of implementing municipal solid waste segregation at the source.Furthermore,depackaging biogenic waste at the source is recommended to substantially alleviate the negative effect of pretreatment on MPs formation. 展开更多
关键词 Microplastics Plastic debris Household biogenic waste Depackage PRETREATMENT
下载PDF
Thermal pretreatment of willow branches impacts yield and pore development of activated carbon in subsequent activation with ZnCl_(2) via modifying cellulose structure
12
作者 Linghui Kong Chao Li +7 位作者 Runxing Sun Shu Zhang Yi Wang Jun Xiang Song Hu Dong Wang Chuanjun Leng Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期227-237,共11页
Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce d... Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce dehydration and/or aromatization to change the structure of cellulose/hemicellulose.This might interfere with evolution of structures of AC,which was investigated herein via thermal pretreatment of willow branch(WB)from 200 to 360℃and the subsequent activation with ZnCl_(2) at 550℃.The results showed that thermal pretreatment at 360℃(WB-360)could lead to substantial pyrolysis to form biochar,with a yield of 31.9%,accompanying with nearly complete destruction of cellulose crystals and remarkably enhanced aromatic degree.However,cellulose residual in WB-360 could still be activated to form AC-360 with specific surface area of 1837.9 m~2·g^(-1),which was lower than that in AC from activation of untreated WB(AC-blank,2077.8 m~2·g^(-1)).Nonetheless,the AC-200 from activation of WB-200 had more developed pores(2113.9 m~2·g^(-1))and superior capability for adsorption of phenol,due to increased permeability of ZnCl_(2) to the largely intact cellulose structure in WB-200.The thermal pretreatment did increase diameters of micropores of AC but reduced the overall yield of AC(26.8%for AC-blank versus 18.0%for AC-360),resulting from accelerated cracking but reduced intensity of condensation.In-situ infrared characterization of the activation showed that ZnCl_(2) mainly catalyzed dehydration,dehydrogenation,condensation,and aromatization but not cracking,suppressing the formation of derivatives of cellulose and lignin in bio-oil.The thermal pretreatment formed phenolic-OH and C=O with higher chemical innerness,which changed the reaction network in activation,shifting morphology of fibrous structures in AC-blank to“melting surface”in AC-200 or AC-280. 展开更多
关键词 Thermal pretreatment Activation with ZnCl_(2) Willow branch Activated carbon Biochar
下载PDF
Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide
13
作者 Yan-Xia Wu Shuo Yin +3 位作者 Shan-Shan Song Xiang Liu Yu-Xuan Deng Xue-Jing Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第9期1599-1605,共7页
AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through an... AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through anterior chamber perfusion,and pretreatment involved administering LbGP via gavage for 7d.After 24h of reperfusion,serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and creatinine(CREA)levels,retinal structure,expression of Caspase-3 and Caspase-8,superoxide dismutase(SOD)activity,and malondialdehyde(MDA)in the retina were measured.RESULTS:The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer(GCL)and nerve fiber layer(NFL)of rats subjected to RIRI,as shown by light microscopy and optical coherence tomography(OCT).Serum AST was higher in the model group than in the blank group(P=0.042),but no difference was found in ALT,AST,and CREA across the LbGP groups and model group.Caspase-3 expression was higher in the model group than in the blank group(P=0.006),but no difference was found among LbGP groups and the model group.Caspase-8 expression was higher in the model group than in the blank group(P=0.000),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).SOD activity was lower in the model group than in the blank group(P=0.001),and the decrease was slower in the 400 mg/kg LbGP group than in the model group(P=0.003).MDA content was higher in the model group than in the blank group(P=0.001),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model.CONCLUSION:LbGP pretreatment exhibits dosedependent anti-inflammatory,and antioxidative effects by reducing Caspase-8 expression,preventing declines of SOD activity,and decreasing MDA content in the RIRI rat model. 展开更多
关键词 retinal ischemia-reperfusion Lycium barbarum glycopeptide PRETREATMENT ANTI-INFLAMMATORY ANTIOXIDATIVE RAT
下载PDF
Effective separation of coal gasification fine slag: Role of classification and ultrasonication in enhancing flotation
14
作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Zhen Li Mengyan Cheng Xiaoyi Chen Tianhao Nan 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期867-880,共14页
Effective separation of residual carbon and ash is the basis for the resource utilization of coal gasification fine slag(CGFS).The conventional flotation process of CGFS has the bottlenecks of low carbon recovery and ... Effective separation of residual carbon and ash is the basis for the resource utilization of coal gasification fine slag(CGFS).The conventional flotation process of CGFS has the bottlenecks of low carbon recovery and high collector dosage.In order to address these issues,CGFS sample taken from Shaanxi,China was used as the study object in this paper.A new process of size classification-fine grain ultrasonic pretreatment flotation(SC-FGUF)was proposed and its separation effect was compared with that of wholegrain flotation(WGF)as well as size classification-fine grain flotation(SC-FGF).The mechanism of its enhanced separation effect was revealed through flotation kinetic fitting,flotation flow foam layer stability,particle size composition,surface morphology,pore structure,and surface chemical property analysis.The results showed that compared with WGF,pre-classification could reduce the collector dosage by 84.09%and the combination of pre-classification and ultrasonic pretreatment could increase the combustible recovery by 17.29%and up to 93.46%.The SC-FGUF process allows the ineffective adsorption of coarse residual carbon to collector during flotation stage to be reduced by pre-classification,and the tightly embedded state of fine CGFS particles is disrupted and surface oxidizing functional group occupancy was reduced by ultrasonic pretreatment,thus carbon and ash is easier to be separated in the flotation process.In addition,some of the residual carbon particles were broken down to smaller sizes in the ultrasonic pretreatment,which led to an increase in the stability of flotation flow foam layer and a decrease in the probability of detachment of residual carbon particles from the bubbles.Therefore,SCFGUF could increase the residual carbon recovery and reduce the flotation collector dosage,which is an innovative method for carbon-ash separation of CGFS with good application prospect. 展开更多
关键词 Coal gasification fine slag Size classification Ultrasonic pretreatment FLOTATION Carbon recovery
下载PDF
Synergetic Bioproduction of Short-Chain Fatty Acids from Waste Activated Sludge Intensified by the Combined Use of Potassium Ferrate and Biosurfactants
15
作者 CHEN Yanyan YAO Shuo +2 位作者 ZHANG Dahai LI Xianguo FENG Lijuan 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期695-709,共15页
The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were expl... The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were explored in this work.Experimental results showed that 0.2 g PF(g TSS)^(-1)(total suspended solid)combined with 0.02 g TS(g TSS)^(-1) could further improve SCFAs’production,and the maximum SCFAs content reached 2008.7 mg COD L^(-1),which is 1.2 and 4.5 times higher than those with PF and TS individually added,respectively,and 5.3 times higher than that of blank WAS on Day 12.In the model substrates experiments,the degradation rates of bovine serum albumin and dextran with combination of PF and TS were 41.3%±0.1% and 48.5%±0.06%,respectively,on Day 3,which are lower than those in blank WAS(with degradation rates of 72.3%±0.5%and 90.3%±0.3%).It was revealed that the oxidative effect of PF and the solubilization of TS caused more organic matters to be dissolved out from WAS,providing a large number of biodegradable substances for subsequent SCFAs production.While WAS pretreated with the combination of PF and TS,the relative abundances of Firmicutes increased from 6.4%(blank)to 38.6%,and that of Proteobacteria decreased from 41.8%(blank)to 21.8%.The combination of PF and TS promoted the hydrolysis process of WAS by enriching Firmicutes,and then increased acetic acid production by inhibiting Proteobacteria that consumed SCFAs.Meanwhile,at the genus level,acidogenesis bacteria(e.g.,Proteiniclasticum and Petrimonas)were enriched whereas SCFAs consuming bacteria(e.g.,Dokdonella)were inhibited. 展开更多
关键词 waste activated sludge anaerobic fermentation potassium ferrate BIOSURFACTANT PRETREATMENT
下载PDF
An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
16
作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
下载PDF
On-site rapid detection of multiple pesticide residues in tea leaves by lateral flow immunoassay
17
作者 Junxia Gao Tianyi Zhang +7 位作者 Yihua Fang Ying Zhao Mei Yang Li Zhao Ye Li Jun Huang Guonian Zhu Yirong Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第2期276-283,共8页
The application of pesticides (mostly insecticides and fungicides) during the tea-planting process will undoubtedly increase the dietary risk associated with drinking tea. Thus, it is necessary to ascertain whether pe... The application of pesticides (mostly insecticides and fungicides) during the tea-planting process will undoubtedly increase the dietary risk associated with drinking tea. Thus, it is necessary to ascertain whether pesticide residues in tea products exceed the maximum residue limits. However, the complex matrices present in tea samples comprise a major challenge in the analytical detection of pesticide residues. In this study, nine types of lateral flow immunochromatographic strips (LFICSs) were developed to detect the pesticides of interest (fenpropathrin, chlorpyrifos, imidacloprid, thiamethoxam, acetamiprid, carbendazim, chlorothalonil, pyraclostrobin, and iprodione). To reduce the interference of tea substrates on the assay sensitivity, the pretreatment conditions for tea samples, including the extraction solvent, extraction time, and purification agent, were optimized for the simultaneous detection of these pesticides. The entire testing procedure (including pretreatment and detection) could be completed within 30 min. The detected results of authentic tea samples were confirmed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), which suggest that the LFICS coupled with sample rapid pretreatment can be used for on-site rapid screening of the target pesticide in tea products prior to their market release. 展开更多
关键词 Lateral flow immunoassay Rapid detection Pesticide multi-residue Tea matrix Sample rapid pretreatment
下载PDF
Effect of hydrogen fluoride and magnesium oxide on AZ31 Mg alloy/carbon fiber-reinforced plastic composite by thermal laser joining technique
18
作者 Andrews Nsiah Ashong Barton Mensah Arkhurst +2 位作者 Youn Seoung Lee Mok-Young Lee Jeoung Han Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期2874-2889,共16页
Although hydrofluoric acid(HF)surface treatment is known to enhance the joining of metals with polymers,there is limited information on its effect on the joining of AZ31 alloy and carbon-fiber-reinforced plastics(CFRP... Although hydrofluoric acid(HF)surface treatment is known to enhance the joining of metals with polymers,there is limited information on its effect on the joining of AZ31 alloy and carbon-fiber-reinforced plastics(CFRPs)through laser-assisted metal and plastic direct joining(LAMP).This study uses the LAMP technique to produce AZ31-CFRP joints.The joining process involves as-received AZ31,HFpretreated AZ31,and thermally oxidized HF-pretreated AZ31 alloy sheets.Furthermore,the bonding strength of joints prepared with thermally oxidized AZ31 alloy sheets is examined to ascertain the combined effect of HF treatment and thermal oxidation on bonding strength.The microstructures,surface chemical interactions,and mechanical performances of joints are investigated under tensile shear loading.Various factors,such as bubble formation,CFRP resin decomposition,and mechanical interlocking considerably affect joint strength.Additionally,surface chemical interactions between the active species on metal parts and the polar amide along with carbonyl groups of polymer play a significant role in improving joint strength.Joints prepared with surface-pretreated AZ31 alloy sheets show significant improvements in bonding strength. 展开更多
关键词 Thermal laser joining Thermal oxidation Hydrofluoric acid pretreatment Mechanical interlocking Covalent bonds Chemical interactions
下载PDF
Technological advancements in millet dehulling and polishing process: An insight into pretreatment methods, machineries and impact on nutritional quality
19
作者 Shagolshem Mukta Singh Jayasree Joshi T P.Srinivasa Rao 《Grain & Oil Science and Technology》 CAS 2024年第3期186-195,共10页
Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions i... Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions in millet dehulling and polishing. These technologies operate based on the fundamental principles of compression-shearing, abrasion-friction, and centrifugal-impact forces. Processing of millets can be challenging because of the physical characteristics and tight attachment of hull and bran to the endosperm. However, several dehullers have been designed to solve this problem for different kinds of millets. In addition, the nutritional and anti-nutritional characteristics undergo alterations due to both dehulling and polishing processes. These alterations are thoroughly examined and discussed in this article. Specifically, anti-nutrients such as tannins and phytate are predominantly found in the outer pericarp of the grain and experience a reduction after undergoing dehulling and polishing. The nutritional properties are also subjected to a reduction;however, this reduction can be mitigated by subjecting the grains to certain pretreatments before dehulling and polishing. These treatments serve to enhance dehulling efficiency and nutrient digestibility while simultaneously reducing the presence of anti-nutrients. Novel thermal and non-thermal methodologies such as microwave, hydrothermal, high-pressure processing, and ohmic heating can be employed for processing millets, thereby diminishing the loss of nutrients. Additional research can be carried out to investigate their impact on the dehulling and polishing of millets. 展开更多
关键词 MILLETS DEHULLING POLISHING PRETREATMENT Novel thermal and non-thermal techniques
下载PDF
Research Progress of QuEChERS Pretreatment Technique in the Detection of Multiple Pesticide Residues
20
作者 Bo LIU Dawei WANG +3 位作者 Yuhang GUO Xuehua WANG Lei WANG Yajuan SONG 《Agricultural Biotechnology》 2024年第2期10-11,37,共3页
The QuEChERS extraction technique is a pretreatment technique that has been rapidly applied in recent years and is widely used in the field of pesticide residues with many advantages. This technique is based on solid ... The QuEChERS extraction technique is a pretreatment technique that has been rapidly applied in recent years and is widely used in the field of pesticide residues with many advantages. This technique is based on solid phase extraction (SPE), which uses the interaction between adsorbent and impurities in the matrix to achieve the purpose of purification. The method has easier operation and better purification effect than SPE. In this paper, the research progress of the QuEChERS technique in pesticide residue detection in different fields in recent years and its future development were reviewed, hoping to provide reference for further development and utilization of the QuEChERS technique in pesticide residue detection in the future. 展开更多
关键词 QUECHERS PRETREATMENT Pesticide residues Research progress
下载PDF
上一页 1 2 25 下一页 到第
使用帮助 返回顶部