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Integration of morphology and electronic structure modulation on cobalt phosphide nanosheets to boost photocatalytic hydrogen evolution from ammonia borane hydrolysis 被引量:2
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作者 Chao Wan Yu Liang +5 位作者 Liu Zhou Jindou Huang Jiapei Wang Fengqiu Chen Xiaoli Zhan Dang-guo Cheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期333-343,共11页
The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy.Ammonia borane(AB)has regarded as a competitive candidate for ... The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy.Ammonia borane(AB)has regarded as a competitive candidate for chemical hydrogen storage.However,developing efficient yet high-performance catalysts towards hydrogen evolution from AB hydrolysis remains an enormous challenge.Herein,cobalt phosphide nanosheets are synthesized by a facile salt-assisted along with low-temperature phosphidation strategy for simultaneously modulating its morphology and electronic structure,and function as hydrogen evolution photocatalysts.Impressively,the Co_(2)P nanosheets display extraordinary performance with a record high turnover frequency of 44.9 min^(-1),outperforming most of the noble-metal-free catalysts reported to date.This remarkable performance is attributed to its desired nanosheets structure,featuring with high specific surface area,abundant exposed active sites,and short charge diffusion paths.Our findings provide a novel strategy for regulating metal phosphides with desired phase structure and morphology for energy-related applications and beyond. 展开更多
关键词 Ammonia borane Hydrogen generation hydrolysis Cobalt phosphide nanosheets PHOTOCATALYSIS
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Research progress on catalysts for organic sulfur hydrolysis: Review of activity and stability
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作者 Bingning Wang Xianzhe Wang +3 位作者 Song Yang Chao Yang Huiling Fan Ju Shangguan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期203-216,共14页
The removal of organic sulfur through catalytic hydrolysis is a significant area of research in the field of desulfurization.This review provides an overview of recent advancements in catalytic hydrolysis technology o... The removal of organic sulfur through catalytic hydrolysis is a significant area of research in the field of desulfurization.This review provides an overview of recent advancements in catalytic hydrolysis technology of organic sulfur,including the activity,stability,and atmosphere effects of hydrolysis catalysts.The emphasis is on strategies for enhancing hydrolysis activity and anti-oxygen poisoning property of catalysts.Surface modification,metal doping and nitrogen doping have been found to improve the activity of catalysts.Alkaline components modification is the most commonly used method,the formation of oxygen vacancies through metal doping and creation of nitrogen basic sites through nitrogen doping also contribute to the hydrolysis of organic sulfur.The strategies for anti-oxygen poisoning are discussed in a systematic manner.The structural regulation of catalysts is beneficial for the desorption and diffusion of hydrogen sulfide(H_(2)S),thereby effectively inhibiting its oxidation.Nitrogen doping and the addition of electronic promoters such as transition metals can protect active sites and decrease the number of active oxygen species.These methods have been proven to enhance the anti-poisoning performance of catalysts.Additionally,this article summarizes how different atmospheres affect the activity of hydrolysis catalysts.The objective of this review is to pave the way for the development of efficient,stable and widely used catalysts for organic sulfur hydrolysis. 展开更多
关键词 Organic sulfur hydrolysis CATALYSTS ACTIVITY STABILITY
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An efficient and mild recycling of waste melamine formaldehyde foams by alkaline hydrolysis
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作者 Shaodi Wu Ning Zhang +7 位作者 Chizhou Wang Xianglin Hou Jie Zhao Shiyu Jia Jiancheng Zhao Xiaojing Cui Haibo Jin Tiansheng Deng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期919-926,共8页
Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin wastes.Herein,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditi... Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin wastes.Herein,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditions(160℃)in a NaOH–H2O system with ammelide and ammeline as the main degradation products.The alkaline solvent had an obvious corrosion effect for MFF,as indicated by scanning electron microscopy(SEM).The reaction process and products distribution were studied by Fourier-transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and ^(13)C nuclear magnetic resonance(NMR).Besides,the MFF degradation products that have the similar chemical structures and bonding performances to those of melamine can be directly used as the raw material for synthesis of melamine urea-formaldehyde resins(MUFs).Moreover,the degradation system demonstrated here showed the high degradation efficiency after reusing for 7 times.The degradation process generated few harmful pollutants and no pre-or post-treatments were required,which proves its feasibility in the safe removal or recovery of waste MFF. 展开更多
关键词 Melamine formaldehyde foam Degradation Alkaline hydrolysis RECYCLING
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In situ formed Mg(BH_(4))_(2) for improving hydrolysis properties of MgH_(2)
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作者 Yongyang Zhu Mili Liu +6 位作者 liming Zeng Yin Wang Daifeng Wu Rui Li Qing Zhou Renheng Tang Fangming Xiao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1204-1214,共11页
The hydrolysis of MgH_(2) delivers high hydrogen capacity(15.2 wt%),which is very attractive for real-time hydrogen supply.However,the formation of a surface passivation Mg(OH)_(2) layer and the large excess of H_(2)O... The hydrolysis of MgH_(2) delivers high hydrogen capacity(15.2 wt%),which is very attractive for real-time hydrogen supply.However,the formation of a surface passivation Mg(OH)_(2) layer and the large excess of H_(2)O required to ensure complete hydrolysis are two key challenges for the MgH_(2) hydrolysis systems.Now,a low-cost method is reported to synthesize MgH_(2)@Mg(BH_(4))_(2) composite via ball-milling MgH_(2) with cheap and widely available B_(2)O_(3)(or B(OH)_(3)).By adding small amounts of B_(2)O_(3),the in-situ formed Mg(BH_(4))_(2) could significantly promote the hydrolysis of MgH_(2).In particular,the MgH_(2)–10 wt%B_(2)O_(3) composite releases 1330.7 mL·g^(−1) H_(2)(close to 80%theoretical hydrogen generation H_(2))in H_(2)O and 1520.4 mL·g^(−1) H_(2)(about 95%)in 0.5 M MgCl_(2) in 60 min at 26℃ with hydrolysis rate of 736.9 mL·g^(−1)·min^(−1) and 960.9 mL·g^(−1)·min^(−1) H_(2) during the first minute of the hydrolysis,respectively.In addition,the MgCl_(2) solution allows repeated use by filtering and exhibits high cycle stability(20 cycles),therefore leading to much reduced capacity loss caused by the excess H_(2)O.We show that by introducing B_(2)O_(3) and recycling the 0.5 M MgCl_(2) solution,the system hydrogen capacity can approach 5.9 wt%,providing a promising hydrogen generation scheme to supply hydrogen to the fuel cells. 展开更多
关键词 hydrolysis MgH_(2) Mg(BH_(4))_(2) Hydrogen generation B_(2)O_(3) MgCl_(2)
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Enzymatic hydrolysis of silkworm pupa and its allergenicity evaluation by animal model with different immunization routes 被引量:3
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作者 Yan Dai Meijia Huang +7 位作者 Yujuan Xu Lixia Mu Jingyan Gao Hongbing Chen Zhihua Wu Anshu Yang Yong Wu Xin Li 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期774-782,共9页
Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allerg... Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allergenicity of protein.In this study,we aimed to investigate the effect of enzymolysis on the allergenicity of silkworm pupa.Crude silkworm pupa protein was extracted through alkali extraction and acid precipitation,which included 5 proteins with the molecular weights ranging from 34 kDa to 76 kDa,and silkworm pupa were then hydrolyzed by alkaline protease.The allergenicity of silkworm pupa protein and its enzymatic hydrolysates was evaluated by establishing BALB/c mice model,and the mice were immunized via intragastric gavage and intraperitoneal injection,respectively.The results indicated that the intraperitoneal inj ection immunization route induced more by detecting with antibodies,histamine and Th2-related cytokines.Moreover,mice treated with silkworm pupa protein peptide displayed no obvious allergic symptoms,indicating that enzyme hydrolytic technique could significantly reduce the allergenicity of silkworm pupa. 展开更多
关键词 Silkworm pupa Silkworm pupa peptides Enzymatic hydrolysis ALLERGENICITY IMMUNIZATION Animal model
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Oxygen vacancy defects engineering on Cu-doped Co_(3)O_(4) for promoting effective COS hydrolysis 被引量:3
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作者 Guanyu Mu Yan Zeng +5 位作者 Yong Zheng Yanning Cao Fujian Liu Shijing Liang Yingying Zhan Lilong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期831-841,共11页
The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of... The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process. 展开更多
关键词 Oxygen vacancy COS hydrolysis In situ spectra Cu doped Co_(3)O_(4)
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Structural and antioxidative properties of royal jelly protein by partial enzymatic hydrolysis 被引量:1
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作者 Shanshan Li Lingchen Tao +3 位作者 Shiqin Peng Xinyu Yu Xiaobin Ma Fuliang Hu 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1820-1827,共8页
The objective of this study was to investigate the structural and antioxidative properties of royal jelly protein(RJP)at different degrees of hydrolysis(DH)by partial enzymatic hydrolysis. RJP was hydrolyzed by alcala... The objective of this study was to investigate the structural and antioxidative properties of royal jelly protein(RJP)at different degrees of hydrolysis(DH)by partial enzymatic hydrolysis. RJP was hydrolyzed by alcalase for 0 min, 15 min, 1 h, 5 h and 8 h to obtain hydrolysates at DH of 5.34%, 11.65%, 15.19%, 21.38% and 23.91%, respectively. With the increased DH, the RJP hydrolysates showed elevated antioxidative activities. The molecular weight of RJP hydrolysates was significantly decreased but their primary backbone kept unchanged. Analysis of circular dichroism spectra revealed that the enzymolysis reduced the content of α-helix but increased the contents of β-sheet, β-turn and random coil. Meanwhile, the surface hydrophobicity and fluorescence intensity of RJP hydrolysates were decreased and a red shift occurred. As the enzymolysis continued, the surface morphology of RJP was gradually changed from a sheet-like structure into microparticles. Changes in antioxidative activities and structures generally followed a DH-dependent manner, however these changes became insignificant for samples at DH beyond 20%. Taking into consideration of both effectiveness and productivity, the optimum enzymatic duration was determined at 5 h. 展开更多
关键词 Royal jelly protein Acalase Enzymatic hydrolysis Antioxidative activity STRUCTURE
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Effects of Potassium Ferrate and Low-Temperature Thermal Hydrolysis Co-Pretreatment on the Hydrolysis and Anaerobic Digestion Process of Waste Activated Sludge
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作者 MA Yingpeng HAO Di +3 位作者 YAO Shuo ZHANG Dahai LI Xianguo FENG Lijuan 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1583-1591,共9页
This study evaluated the effect of potassium ferrate(PF)and low-temperature thermal hydrolysis co-pretreatment on the promotion of sludge hydrolysis process and the impact on acid production in the subsequent anaerobi... This study evaluated the effect of potassium ferrate(PF)and low-temperature thermal hydrolysis co-pretreatment on the promotion of sludge hydrolysis process and the impact on acid production in the subsequent anaerobic digestion process.The analytical investigations showed that co-pretreatment significantly facilitated the hydrolysis process of the sludge and contributed to the accumulation of short-chain fatty acids(SCFAs).The pretreatment conditions under the optimal leaching of organic matter from sludge were hydrothermal temperature of 75℃,hydrothermal treatment time of 12 h,and PF dosage of 0.25 g g^(−1)TSS(total suspended solids),according to the results of orthogonal experiments.By pretreatment under proper conditions,the removal rate of soluble chemical oxygen demand(SCOD)achieved 71.8%at the end of fermentation and the removal rate of total phosphorus(TP)was 69.1%.The maximum yield of SCFAs was 750.3 mg L^(−1),7.45 times greater than that of the blank group.Based on the analysis of the anaerobic digestion mechanism,it was indicated that the co-pretreatment could destroy the floc structure on the sludge surface and improve organic matter dissolving,resulting in more soluble organic substances for the acidification process.Furthermore,microbial community research revealed that the main cause of enhanced SCFAs generation was an increase in acidogenic bacteria and a reduction of methanogenic bacteria. 展开更多
关键词 waste activated sludge potassium ferrate low-temperature thermal hydrolysis anaerobic digestion short-chain fatty acids
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Catalytic Hydrolysis of CFC-12 over MoO_(3)/ZrO_(2)-TiO_(2)
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作者 谭小芳 ZHOU Tong +3 位作者 LI Zhiqian REN Guoqing JIA Lijuan 刘天成 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期59-64,共6页
Solid acid MoO_(3)/ZrO_(2)-TiO_(2)catalysts were prepared by impregnation method,and catalytic hydrolysis of difluorodichloromethane(CFC-12)over the catalyst was studied.The presence of MoO_(3)/ZrO_(2)-TiO_(2)catalyst... Solid acid MoO_(3)/ZrO_(2)-TiO_(2)catalysts were prepared by impregnation method,and catalytic hydrolysis of difluorodichloromethane(CFC-12)over the catalyst was studied.The presence of MoO_(3)/ZrO_(2)-TiO_(2)catalyst in polycrystalline state could be clearly observed by transmission electron microscopy(TEM).Mesopores were detected by N2 adsorption-desorption isotherms which further confirmed the MoO_(3)/ZrO_(2)-TiO_(2)structural characteristics of catalyst.The results of NH_(3)-TPD showed that the calcination temperatures had a great influence on the acidity of the catalyst,and the weak acidic site had a strong catalytic activity for the catalytic hydrolysis of CFC-12.Moreover,ZrO_(2)-TiO_(2)was highly dispersed in the MoO_(3)framework,suggested by powder X-ray diffraction(XRD)and N_(2)adsorption-desorption results.The effects of the catalyst calcination temperatures on the conversion rate of CFC-12 were studied.The effects of catalytic hydrolysis temperatures and water vapor concentration on the catalytic hydrolysis rate of CFC-12 were also studied.The solid acid MoO_(3)/ZrO_(2)-TiO_(2)was calcined at 500℃for 3 h at a catalytic hydrolysis temperature of 400℃and water vapor concentration of 83.18%,and catalytic hydrolysis rate of CFC-12 reached 98.65%.The hydrolysis rate of CFC-12 remained above 65.34%after 30 hours continuous reaction. 展开更多
关键词 catalytic hydrolysis difluorodichloromethane(CFC-12) MoO_(3)/ZrO_(2)-TiO_(2) solid acid catalyst
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Preliminary Study on the Treatment Efficiency of Pasteurized Lime Thermal Alkaline Hydrolysis for Excess Activated Sludge and Reduction of Tetracycline Resistance Genes
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作者 Maoxia Chen Qixuan Zhou +3 位作者 Jiayue Zhang Jiaoyang Li Wei Zhang Huan Liu 《Journal of Renewable Materials》 EI 2023年第10期3711-3723,共13页
Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in thi... Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in this study to improve the efficiency of pretreatment method.Direct thermal hydrolysis(TH),pasteurized thermal hydrolysis(PTH),and alkaline pasteurized thermal hydrolysis(PTH+CaO and PTH+NaOH)methods were used to treat EAS.Each method was compared and analyzed in terms of dissolution in ammonium nitrogen(NH_(4)^(+)-N)and soluble COD(SCOD)in EAS.Furthermore,the removal of tetracycline resistance genes(TRGs)and class 1 transposon gene intI1 from EAS was investigated.The NH_(4)^(+)-N and SCOD concentrations in EAS treated by PTH were 1.24 and 2.58 times higher than those of TH.However,the removal efficiency of total TRGs and intI1 between the groups was comparable.The SCOD concentration of the PTH+NaOH group was 4.37 times higher than that of the PTH group,and the removal efficiency of total TRGs was increased by 9.52%compared with that by PTH.The NH_(4)^(+)-N and SCOD concentrations of the PTH+CaO group could reach 85.04%and 92.14%of the PTH+NaOH group,but the removal efficiency of total TRGs by PTH+CaO was 19.78%lower than that by PTH+NaOH.Thus,to reduce the financial cost in actual operation,lime(CaO)can be used instead of a strong alkali(NaOH),and pasteurized steam at 70℃ instead of conventional high-temperature heating to treat EAS.This study provides a reference for the development of alkaline hydrolysis under moderate temperatures along with the removal of TRGs in EAS. 展开更多
关键词 Excess activated sludge tetracycline resistance genes thermal alkaline hydrolysis LIME pasteurized thermal hydrolysis
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Hydrogel-based catalysts for hydrogen generation by the hydrolysis of B–H compounds under external physical fields
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作者 Chunling Qin Wenliu Wu +4 位作者 Hassanien Gomaa Shuai Wu Cuihua An Qibo Deng Ning Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期518-535,I0011,共19页
Hydrogen is a popular clean high-energy-density fuel.However,its utilization is limited by the challenges toward low-cost hydrogen production and safe hydrogen storage.Fortunately,these issues can be addressed using p... Hydrogen is a popular clean high-energy-density fuel.However,its utilization is limited by the challenges toward low-cost hydrogen production and safe hydrogen storage.Fortunately,these issues can be addressed using promising hydrogen storage materials such as B–H compounds.Hydrogen stored in B–H compounds can be released by hydrolysis at room temperature,which requires catalysts to increase the rate of the reaction.Recently,several effective approaches have been developed for hydrogen generation by catalyzing the hydrolysis of B–H compounds.This review summarizes the existing research on the use of nanoparticles loaded on hydrogels as catalysts for the hydrolysis of B–H compounds.First,the factors affecting the hydrolysis rate,such as temperature,p H,reactant concentration,and type of nano particles,were investigated.Further,the preparation methods(in situ reduction,one-pot method,template adsorption,etc.)for the hydrogel catalysts and the types of loaded catalysts were determined.Additionally,the hydrogel catalysts that can respond to magnetic fields,ultrasound fields,optical fields,and other physical fields are introduced.Finally,the issues and future developments of hydrogel-based catalysts are discussed.This review can inspire deeper investigations and provide guidance for the study of hydrogel catalysts in the field of hydrogen production via hydrolysis. 展开更多
关键词 HYDROGEL Nanoparticlec atalyst B-H compounds hydrolysis reaction External physical field
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Effect of acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust in subcritical water
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作者 Wei Yang Yalun Ma +6 位作者 Xu Zhang Fan Yang Dong Zhang Shengji Wu Huanghu Peng Zezhou Chen Lei Che 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期195-204,共10页
The effects of sulfuric acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust were investigated in this study.Sulfuric acid could act as an acidic catalyst to depolymerize holocellulose th... The effects of sulfuric acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust were investigated in this study.Sulfuric acid could act as an acidic catalyst to depolymerize holocellulose through cleavage of the glycosidic bonds,the dissociation energies of which were supplied by the impact of a ball on pine sawdust,during milling.The destruction of glycosidic and hydrogen bonds in pine sawdust resulted in a decrease of crystallinity and an increase of water solubility.The sulfuric acid could promote the hydrolysis of holocellulose and its hydrolysis products.It also destroyed the chemical linkages between holocellulose and lignin during ball milling.The cleavage of chemical linkages with holocellulose made lignin more difficult to hydrolyze in subcritical water,and higher activation energy was needed to hydrolyze pretreated pine sawdust at higher reaction temperatures.It also led to the formation of glucose char and aromatic-linked polymer char from the hydrolysis products of holocellulose. 展开更多
关键词 Acid-associated mechanical pretreatment Subcritical water Pine sawdust hydrolysis behavior Kinetic parameters
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Glucosinolates and Their Hydrolysis Products in Arabidopsis thaliana Influence Performance and Feeding Choice of Pieris rapae and Spodoptera exigua
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作者 Julie A. Kemarly-Dowland Maria Gabriela Bidart 《Advances in Entomology》 2023年第4期285-299,共15页
Glucosinolates and their hydrolysis products, found in plants of the order Brassicales, are well-known for their defensive properties against insect herbivores. Arabidopsis thaliana (Col-0) genetic lines with mutation... Glucosinolates and their hydrolysis products, found in plants of the order Brassicales, are well-known for their defensive properties against insect herbivores. Arabidopsis thaliana (Col-0) genetic lines with mutations that modify the type of glucosinolates (i.e. myb28myb29 and cyp79B2cyp79B3 are deficient in the production of aliphatic and indolyl glucosinolates, respectively) make it possible to test for the specific effects of these secondary chemicals on insect herbivores. The Pad3 mutant (deficient in camalexin), which has a role in resistance to pathogens, was also tested. Likewise, the effects of different glucosinolate hydrolysis products can be evaluated using genetically modified (GM) lines of the wild type Col-0 ecotype, which naturally produces isothiocyanates. These GM lines include the nitrile-producing 35S: ESP and the double knockout tgg1tgg2, which virtually lacks hydrolysis products. In both no-choice and choice experiments, the crucifer specialist Pieris rapae was virtually unaffected by differences in the type of glucosinolates or hydrolysis products. In contrast, the generalist insect Spodoptera exigua had statistically significant increases in pupae/adult weight and faster developmental times when reared on mutants deficient in the production of aliphatic and indolyl glucosinolates and their hydrolysis products. There were no differences in the performance of either insect species when reared on wild type Col-0 or Pad3. Results from feeding choice trials showed that Pieris rapae had no statistically significant preference for any of the genetic lines. In contrast, Spodoptera exigua had a significant feeding preference for the double mutant tgg1tgg2. This study provides evidence that variation in the type of glucosinolates and their hydrolysis products can influence insect performance and feeding choices, and that responses are species-specific. 展开更多
关键词 Arabidopsis thaliana GLUCOSINOLATES hydrolysis Products Specialist and Generalist Insects
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重组木聚糖酶的高密度发酵及其定向制备低聚木糖
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作者 赵剑 解静聪 +3 位作者 姜越 杨静 徐浩 张宁 《林产化学与工业》 CAS CSCD 北大核心 2024年第1期97-104,共8页
为提高酶水解杨木木聚糖定向转化低聚木糖的效率,同时降低酶法制备低聚木糖的成本,围绕重组大肠杆菌(PET-PdoXyn10A-DE3)高密度发酵制备拟杆菌来源木聚糖酶PdoXyn10A的诱导表达条件和酶水解制备低聚木糖的工艺条件开展了研究。考察了在... 为提高酶水解杨木木聚糖定向转化低聚木糖的效率,同时降低酶法制备低聚木糖的成本,围绕重组大肠杆菌(PET-PdoXyn10A-DE3)高密度发酵制备拟杆菌来源木聚糖酶PdoXyn10A的诱导表达条件和酶水解制备低聚木糖的工艺条件开展了研究。考察了在5 L发酵罐水平下诱导剂浓度、诱导光密度(OD_(600))值、诱导温度和诱导pH值等因素对PET-PdoXyn10A-DE3产重组木聚糖酶PdoXyn10A的影响,反应温度、pH值对玉米芯木聚糖酶水解过程中酶活力的影响,以及酶添加量、酶水解时间对杨木乙酸水解液制备低聚木糖的影响。研究结果表明:在诱导剂浓度0.25 mmol/L、诱导OD_(600)值55、诱导温度34℃和诱导pH值7.0的最佳诱导条件下,经高密度发酵重组酶酶活力可达362.67 U/mL,重组大肠杆菌生物量可达28.83 g/L。酶水解制备低聚木糖的最佳条件为酶反应温度40℃、pH值5.2、酶添加量12 U/mL和反应时间6 h,此条件下低聚木糖的量为3.21 g/L,其中木二糖、木三糖、木四糖、木五糖和木六糖的量分别为1.09、 0.97、 0.84、 0.18、 0.13 g/L,木糖为1.82 g/L。 展开更多
关键词 重组木聚糖酶 高密度发酵 乙酸水热反应 低聚木糖 酶水解条件
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基于废旧棉织物的CNCs制备及增强应用研究
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作者 张涛 郭红 +2 位作者 赵晓婉 甘胜华 侯文生 《棉纺织技术》 CAS 2024年第8期87-92,共6页
为实现废旧棉织物的高值化回收利用,采用酸解法将其水解制备成纤维素纳米晶体(CNCs),通过多种表征方法分析了制备的CNCs的形貌尺寸及理化特性,并探究CNCs对PVA膜力学性能的增强效果。结果表明:制备的CNCs呈短棒状结构,长度168 nm±7... 为实现废旧棉织物的高值化回收利用,采用酸解法将其水解制备成纤维素纳米晶体(CNCs),通过多种表征方法分析了制备的CNCs的形貌尺寸及理化特性,并探究CNCs对PVA膜力学性能的增强效果。结果表明:制备的CNCs呈短棒状结构,长度168 nm±71 nm,直径19 nm±11 nm,收率54.2%;CNCs的Zeta电位值-31.8 mV,分散稳定性良好,且热稳定性较棉织物有一定程度下降;CNCs仍为纤维素Ⅰ型结构,结晶度80.8%。CNCs质量分数为5%时,PVA复合膜拉伸断裂强度和断裂伸长率较原PVA膜分别提高了37.8%和32.7%。认为:硫酸水解废旧棉织物制备CNCs性能良好,显著增强了PVA复合膜的力学性能,拓宽了废旧棉织物循环利用途径。 展开更多
关键词 废旧棉织物 纤维素纳米晶 酸法水解 PVA复合膜 力学性能
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深层碳酸盐岩储层酸压进展与展望 被引量:2
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作者 郭建春 苟波 +4 位作者 陆灯云 刘子豪 肖彬 徐科 任冀川 《钻采工艺》 CAS 北大核心 2024年第2期121-129,共9页
酸压改造是深层碳酸盐岩储层高效勘探开发的技术利器。随着勘探开发逐渐迈向特深层,厘清目前酸压技术发展现状与趋势至关重要。从酸压裂缝起裂与扩展、酸刻蚀水力裂缝与导流能力构建、酸压数值模拟技术3个方面阐释了酸压改造机理;分析... 酸压改造是深层碳酸盐岩储层高效勘探开发的技术利器。随着勘探开发逐渐迈向特深层,厘清目前酸压技术发展现状与趋势至关重要。从酸压裂缝起裂与扩展、酸刻蚀水力裂缝与导流能力构建、酸压数值模拟技术3个方面阐释了酸压改造机理;分析了黏度控制型、生酸时间控制型、H+屏蔽吸附型、非盐酸基型等4类耐高温缓速酸液体系特点;系统梳理了我国深层碳酸盐岩酸压工艺技术发展的4个历程,剖析了目前9000 m以深特深层碳酸岩酸压面临的4个挑战:能否压开储层、地层温度突破酸液体系耐温极限、高温高压测试手段缺乏、储集体靶向沟通难度大。基于此,提出了5个酸压研究展望:特深井破裂压力精准预测、耐220℃多功能酸液体系研发、超高温高压实验平台构建、全在线酸压技术、超临界CO_(2)酸压技术探索,力求实现特深层碳酸盐岩高效立体开发。 展开更多
关键词 深层超深层 特深层 碳酸盐岩 酸压机理 酸液体系 酸压工艺
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小尾寒羊不同部位风味物质与风味前体物的相关性分析 被引量:1
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作者 王宇 淑英 +4 位作者 王慧婷 张旭 梁孙硕 焦颖雪 张志胜 《中国食品学报》 EI CAS CSCD 北大核心 2024年第1期263-277,共15页
以6~7月龄、体质量为50 kg的小尾寒羊为实验对象,选取颈肉(NM)、里脊(LLDM)和腿肉(RG),对小尾寒羊挥发性风味物质、脂肪酸和氨基酸进行相关性分析。结果表明:在3个部位共检测到45种挥发性风味物质,其中醛类是最主要的挥发性风味物质,占... 以6~7月龄、体质量为50 kg的小尾寒羊为实验对象,选取颈肉(NM)、里脊(LLDM)和腿肉(RG),对小尾寒羊挥发性风味物质、脂肪酸和氨基酸进行相关性分析。结果表明:在3个部位共检测到45种挥发性风味物质,其中醛类是最主要的挥发性风味物质,占总挥发性风味物质的50%左右。经主成分分析得知,庚醛、壬醛、苯甲醛等24种风味物质是导致不同部位间挥发性风味物质差异的主要影响因素。LLDM中对人体有益的单不饱和脂肪酸和多不饱和脂肪酸含量均为最高,脂肪酸比例更符合人体对羊肉脂肪酸营养价值的需求,对人体健康更有益。氨基酸中以谷氨酸(Glu)和赖氨酸(Lys)为主,约占总氨基酸的17%和10%,其中RG除蛋氨酸(Met)、酪氨酸(Tyr)、赖氨酸(Lys)外含量均为最高,且除谷氨酸(Glu)和脯氨酸(Pro)外与LLDM差异不显著,与NM差异均显著。相关性分析表明,多不饱和脂肪酸与大多数挥发性风味物质呈正相关,且与醛类、醇类和芳香类等挥发性风味物质呈显著正相关,这可能是因为多不饱和脂肪酸极易氧化,在氧化过程中生成醛类、醇类和芳香类等物质。氨基酸与大多数醛类和醇类都呈正相关,这可能是因为氨基酸通过转氨反应等一系列反应,最终生成醛类和醇类等物质。 展开更多
关键词 小尾寒羊 不同部位 挥发性风味物质 脂肪酸 氨基酸 相关性
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羊乳清蛋白部分和深度水解工艺、水解物致敏性及肽谱分析
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作者 李红娟 李梦凡 +3 位作者 曹洪宇 刘雷 牟善波 于景华 《食品科学技术学报》 EI CAS CSCD 北大核心 2024年第3期81-91,共11页
利用羊乳清蛋白制备低致敏性配料是目前乳品工业的研究热点。乳清蛋白是乳中主要的蛋白质之一,也是引起婴幼儿过敏反应的主要成分,将蛋白质水解为小分子肽是降低其致敏性的有效方法。以山羊乳清蛋白为原料,研究了部分水解乳清蛋白和深... 利用羊乳清蛋白制备低致敏性配料是目前乳品工业的研究热点。乳清蛋白是乳中主要的蛋白质之一,也是引起婴幼儿过敏反应的主要成分,将蛋白质水解为小分子肽是降低其致敏性的有效方法。以山羊乳清蛋白为原料,研究了部分水解乳清蛋白和深度水解乳清蛋白的水解工艺和水解物特性(水解度、分子质量分布和β-乳球蛋白抗原性),并利用液相色谱串联质谱法(L C-MS/MS)比较了部分水解和深度水解工艺中过敏表位酶切位点的差异。研究结果表明,中性蛋白酶和碱性蛋白酶对羊乳清蛋白水解效果较好,其中碱性蛋白酶的水解度最高,达21.26%。经电泳分析,单酶水解后的产物中仍存在大分子多肽链,深度水解工艺需要复合酶水解。在酶底比为4000 U/g时,使用碱性蛋白酶在pH值为10.0、温度为55℃条件下水解羊乳清蛋白1.0 h,部分水解产物的水解度为12.31%,分子质量在5 kDa以下的多肽占95.18%,β-乳球蛋白抗原性下降率为9.40%。中性蛋白酶和碱性蛋白酶的质量比为1∶1,酶底比为6000 U/g,在pH值为8.5、温度为50℃条件下,水解羊乳清蛋白3.0 h,深度水解产物的水解度为35.58%,分子质量低于3 kDa的多肽为97.26%,β-乳球蛋白抗原性下降率为40.97%。部分水解和深度水解均能破坏β-乳球蛋白的大部分过敏表位,但相较于部分水解,深度水解能更大程度地降低乳清蛋白的致敏性。研究旨在为低致敏性羊水解乳清蛋白的生产提供一定的理论参考。 展开更多
关键词 羊乳清蛋白 水解 分子质量分布 水解度 致敏性
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不同气象条件对高油酸花生产量的影响 被引量:2
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作者 胡延岭 杨海棠 +8 位作者 李盼 于沐 石彦召 刘软枝 朱桢桢 韩艳红 郑晓川 赵利民 《中国油料作物学报》 CAS CSCD 北大核心 2024年第1期129-134,共6页
以河南、山东等5个花生主要产区培育的19个高油酸花生新品种为材料,于2019年~2021年连续3年在郑州种植,采集3年间花生关键生育期(6月~9月)的旬平均气温、旬降水量和旬日照时数等气象数据,结合各个品种的产量数据进行综合分析。研究结果... 以河南、山东等5个花生主要产区培育的19个高油酸花生新品种为材料,于2019年~2021年连续3年在郑州种植,采集3年间花生关键生育期(6月~9月)的旬平均气温、旬降水量和旬日照时数等气象数据,结合各个品种的产量数据进行综合分析。研究结果表明,不同的品种对于气温、降水量和日照时数的敏感程度不同,冀花16、冀花11对开花下针期的温度和日照时数比较敏感,该时期的异常高温会致使其产量明显下降。中花413、中花412和花育917的产量与旬降水量成显著负相关,耐涝程度较差。对品种的稳定性分析表明,开农1768、南充1704、冀农16、开选016、花育961、郑农花25、郑农花23、冀农11、花育633和1508G等10个高油酸品种为年际间稳定性较好的品种,研究结论为高油酸品种的培育及深入利用提供了指导。 展开更多
关键词 花生 高油酸 气象条件 产量
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多孔秸秆碳磺酸催化纤维素水解研究
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作者 陆佳 苏小红 刘泽 《化学工程师》 CAS 2024年第4期1-5,共5页
以玉米秸秆为原料、NaOH为造孔剂,采用碳化-活化制备多孔秸秆碳磺酸(PSCSA),用于纤维素的水解。通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)、N_(2)吸脱附分析(BET)、扫描电子显微镜(SEM)等对PSCSA进行表征分析,表明PSCSA为不定形碳结构... 以玉米秸秆为原料、NaOH为造孔剂,采用碳化-活化制备多孔秸秆碳磺酸(PSCSA),用于纤维素的水解。通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)、N_(2)吸脱附分析(BET)、扫描电子显微镜(SEM)等对PSCSA进行表征分析,表明PSCSA为不定形碳结构并有部分微弱的石墨结晶,含有羟基(-OH)、羧基(-COOH)、磺酸基(-SO_(3)H),且表面为多孔形貌。在多孔秸秆碳磺酸添加量为2.5g·g^(-1)(纤维素)、底物纤维素浓度为3mg·mL^(-1)、190℃水解1h的条件下,多孔秸秆碳磺酸催化纤维素水解还原糖得率可达60.61%。 展开更多
关键词 纤维素 水解 多孔秸秆碳磺酸 还原糖
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