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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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CO_(2) conversion to solar fuels and chemicals:Opening the new paths
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作者 Gabriele Centi Claudio Ampelli 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期680-683,共4页
This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems... This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(i.e.CO_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified technologies.Among the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(PV-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)efficiency.However,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up process.Using approaches that minimize downstream separation costs is also mandatory.Many limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the electrocatalysts.As examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed production.Based on these developments,future directions,such as producing fertilizers and food components from the air,are outlined.The aim is to provide new ideas and research directions from a personal perspective. 展开更多
关键词 Solar fuels Artificial leaf PEC devices PV-EC devices Cell engineering green H_(2) chemicals from theair
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Catalytic conversion of lignocellulosic biomass into chemicals and fuels 被引量:9
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作者 Weiping Deng Yunchao Feng +21 位作者 Jie Fu Haiwei Guo Yong Guo Buxing Han Zhicheng Jiang Lingzhao Kong Changzhi Li Haichao Liu Phuc T.T.Nguyen Puning Ren Feng Wang Shuai Wang Yanqin Wang Ye Wang Sie Shing Wong Kai Yan Ning Yan Xiaofei Yang Yuanbao Zhang Zhanrong Zhang Xianhai Zeng Hui Zhou 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期10-114,共105页
In the search of alternative resources to make commodity chemicals and transportation fuels for a low carbon future,lignocellulosic biomass with over 180-billion-ton annual production rate has been identified as a pro... In the search of alternative resources to make commodity chemicals and transportation fuels for a low carbon future,lignocellulosic biomass with over 180-billion-ton annual production rate has been identified as a promising feedstock.This review focuses on the state-of-the-art catalytic transformation of lignocellulosic biomass into value-added chemicals and fuels.Following a brief introduction on the structure,major resources and pretreatment methods of lignocellulosic biomass,the catalytic conversion of three main components,i.e.,cellulose,hemicellulose and lignin,into various compounds are comprehensively discussed.Either in separate steps or in one-pot,cellulose and hemicellulose are hydrolyzed into sugars and upgraded into oxygen-containing chemicals such as 5-HMF,furfural,polyols,and organic acids,or even nitrogen-containing chemicals such as amino acids.On the other hand,lignin is first depolymerized into phenols,catechols,guaiacols,aldehydes and ketones,and then further transformed into hydrocarbon fuels,bioplastic precursors and bioactive compounds.The review then introduces the transformations of whole biomass via catalytic gasification,catalytic pyrolysis,as well as emerging strategies.Finally,opportunities,challenges and prospective of woody biomass valorization are highlighted. 展开更多
关键词 Lignocelullose BIOMASS Catalytic conversion Biofuels Renewable chemicals
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Surface modification of Cu_(2)O with stabilized Cu^(+) for highly efficient and stable CO_(2) electroreduction to C_(2+) chemicals
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作者 Ziyu Zhou Shuyu Liang +4 位作者 Jiewen Xiao Tianyu Zhang Min Li Wenfu Xie Qiang Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期277-285,共9页
Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for cat... Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for catalyzing CO_(2) to C_(2+) chemicals because of their unique electronic structure.However,the active Cu^(+) species are prone to be reduced to metallic Cu under an electroreduction environment,thus resulting in fast deactivation and poor selectivity.Here,we developed an advanced surface modification strategy to maintain the active Cu^(+) species via assembling a protective layer of metal-organic framework(copper benzenetricarboxylate,CuBTC) on the surface of Cu_(2)O octahedron(Cu_(2)O@CuBTC).It's encouraging to see that the Cu_(2)O@CuBTC heterostructure outperforms the bare Cu_(2)O octahedron in catalyzing CO_(2) to C_(2+) chemicals and dramatically enhances the ratio of C_(2)H_(4)/CH_(4) products.A systematic study reveals that the introduced CuBTC shell plays a critical role in maintaining the active Cu^(+) species in Cu_(2)O@CuBTC heterostructure under reductive conditions.This work offers a practical strategy for improving the catalytic performance of CO_(2)RR over copper oxides and also establishes a route to maintain the state of valence-sensitive catalysts. 展开更多
关键词 CO_(2)RR Copper Oxide Metal-organic Framework Core-shell Structure C_(2+)chemicals
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Chemicals Used in Polymeric Material Coated Waste Paper Composites
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作者 Zübeyde Bülbül Birol Üner 《Journal of Materials Science and Chemical Engineering》 2023年第5期1-10,共10页
In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), ... In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), Titanate and Silanyl (Vinyltriethoxysilane) were added waste paper. Composite boards were pressed and cut in 1 × 30 × 30 cm. In order to identify some properties of the produced boards, experimental works were applied according to the standards. In conclusion, bending stress reduced with filler materials and chemicals was reduced even more than the bending stress except for some experimental groups. In addition, it was observed that the coupling chemicals increased the bending strength and modulus of elasticity compared to the fillers. 展开更多
关键词 Matching chemicals Paper Composites Filling Materials POLYMERS Coupling Agents Paper Fibers
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Endocrine-Disrupting Chemicals: Possible Genesis of Ovarian Tumors
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作者 Kasonde Chanda Ziwei Wang +2 位作者 Shen Ning Xue Bin Yingxiao Yan 《Open Journal of Obstetrics and Gynecology》 2023年第6期1025-1037,共13页
Background: Prolonged exposure to environmental toxicants like endocrine-disrupting chemicals has been linked to several ovarian pathologies. Exposure to endocrine-disrupting chemicals may start at any time of life fr... Background: Prolonged exposure to environmental toxicants like endocrine-disrupting chemicals has been linked to several ovarian pathologies. Exposure to endocrine-disrupting chemicals may start at any time of life from the fetal stage to adulthood resulting in various health complications The purpose of our study is to compare the concentration levels and association of benzopyrene, bisphenol A and genistein in patients with ovarian tumors and normal control group. We also sort to evaluate the predictive performance of benzopyrene, bisphenol A and genistein in patients with ovarian tumors. Methods: A case-control study was conducted for randomly selected participants involving 30 patients and 30 controls. 30 patients with radiologically diagnosed and histopathological confirmed ovarian tumors were included in the study between January 2022 and December 2022. Urine samples from each group were analyzed using liquid chromatography-mass spectrometry. Descriptive analysis for normally distributed continuous variables was done accordingly. Concentration levels of endocrine-disrupting chemicals were assessed using the Mann-Whitney test. The association of endocrine-disrupting chemicals with pathological ovarian tumors was analyzed using binary logistic regression. Evaluation of the diagnostic performance of endocrine-disrupting chemicals was analyzed using the ROC curve. Results: Overall, patients were significantly (P = 0.000) older than the healthy controls. Mean years (SD) were 36.7 (7.90) and 28.8 years (4.89) for patients and normal women respectively. Endometriomas had the highest incidence of 50%. The level of benzopyrene and bisphenol A in patients was significantly higher than those in the control group, while the level of genistein was significantly higher in normal controls. Benzopyrene and bisphenol A were significantly associated with ovarian cysts, and the incidence of pathological ovarian cysts was positively correlated to these EDCs, with OR value 64.79 (P = 0.005) for benzopyrene and 9.609 (P = 0.001) for bisphenol A. Genistein was significantly negatively correlated with the incidence of pathological ovarian tumors, with OR value of 0.153 (P = 0.007). Diagnostic performance on the AUC for benzopyrene, bisphenol A and genistein&l. 展开更多
关键词 Environmental Toxicants Endocrine-Disrupting Chemical Ovarian Cyst Ovarian Tumor
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Research progress on preparation and purification of fluorine-containing chemicals in lithium-ion batteries 被引量:1
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作者 Xiaobin Liu Zhenguo Gao +2 位作者 Jingcai Cheng Junbo Gong Jingkang Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期73-84,共12页
With the development of digital products,electric vehicles and energy storage technology,electronic chemicals play an increasingly prominent role in the field of new energy such as lithium-ion batteries.Electronic che... With the development of digital products,electric vehicles and energy storage technology,electronic chemicals play an increasingly prominent role in the field of new energy such as lithium-ion batteries.Electronic chemicals have attracted extensive attention in various fields.Characteristics of high-end electronic chemicals are high purity and low impurity content,which requires a very strict separation and purification process.At present,crystallization is a key technology for their separation and purification of electronic chemicals.In this work,the representative fluorine-containing compounds in cathode and anode materials,separator and electrolyte of lithium-ion batteries are introduced.The latest technologies for the preparation and purification of four kinds of fluorine-containing battery chemicals by crystallization technology are reviewed.In addition,the research prospects and suggestions are put forward for the separation of fluorine-containing battery chemicals. 展开更多
关键词 Battery chemicals Lithium-ion batteries CRYSTALLIZATION Fluorine-containing chemicals
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Wettability changes of wheat straw treated with chemicals and enzymes 被引量:7
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作者 SHEN Jiang-hua LIU Zhi-ming LI Jing NIU Jing 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期107-110,共4页
A study was conducted to test wettability changes of the wheat straw treated with different methods for the preparation of wheat straw particle board. The wheat straws were separately sprayed with two chemicals (0.6%... A study was conducted to test wettability changes of the wheat straw treated with different methods for the preparation of wheat straw particle board. The wheat straws were separately sprayed with two chemicals (0.6% NaOH, 0.3% H2O2) and three enzymes (lipase, xylanase, cellulase). The contact angle between water and the surface of wheat straw was measured and the spreading-penetration parameters (K-values) were also calculated with wetting model. The surfaces of treated wheat straw and control sample were scanned by means of Micro-FTIR, and their peaks arrangements were analyzed. The surface morphologies of treated wheat straw and control sample were also observed by SEM. Chemical etching was found on the exterior surfaces of the straws treated separately with 0.6% NaOH and 0.3% H2O2; furthermore, the spreading-penetration parameters (K-values) of the distilled water on the exterior surfaces of the treated wheat straw along the grain were higher than that of control. The wettability of exterior surfaces of the wheat straws treated separately with lipase, xylanase and cellulose were improved after treating for seven days, and among the three enzymes treatments, the lipase treatment showed best result. The lipase treatment and NaOH treatment were determined as better methods for improving the wettability of wheat straw surfaces. However, in the economic aspect, NaOH treatment was more practical and easier in the pretreatment for the manufacture of straw particle board. 展开更多
关键词 wheat straw WETTABILITY contact angle chemicals ENZYME
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Recent advances on the reduction of CO2 to important C2+ oxygenated chemicals and fuels 被引量:4
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作者 Jiachen Li Liguo Wang +3 位作者 Yan Cao Chanjuan Zhang PengHe Huiquan Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第11期2266-2279,共14页
The chemical utilization of CO_2 is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO_2 into a wide variety of C_(2+) important chemicals and fuels has received co... The chemical utilization of CO_2 is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO_2 into a wide variety of C_(2+) important chemicals and fuels has received considerable attention as an emerging technology. Since CO_2 is thermodynamically stable and kinetically inert, the effective activation of CO_2 molecule for the selective transformation to target products still remains a challenge. The welldesigned CO_2 reduction route and efficient catalyst system has imposed the feasibility of CO_2 conversion into C_(2+) chemicals and fuels. In this paper, we have reviewed the recent advances on chemical conversion of CO_2 into C_(2+) chemicals and fuels with wide practical applications, including important alcohols, acetic acid, dimethyl ether, olefins and gasoline. In particular, the synthetic routes for C\\C coupling and carbon chain growth, multifunctional catalyst design and reaction mechanisms are exclusively emphasized. 展开更多
关键词 CO2 REDUCTION C2+ chemicals Fuels CATALYSIS
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Selective electrocatalytic conversion of methane to fuels and chemicals 被引量:5
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作者 Shunji Xie Shengqi Lin +2 位作者 Qinghong Zhang Zhongqun Tian Ye Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第6期1629-1636,共8页
The increase in natural gas reserves makes methane a significant hydrocarbon feedstock. However, thedirect catalytic conversion of methane into liquid fuels and useful chemicals remains a great challenge,and many stud... The increase in natural gas reserves makes methane a significant hydrocarbon feedstock. However, thedirect catalytic conversion of methane into liquid fuels and useful chemicals remains a great challenge,and many studies have been devoted to this field in the past decades. Electrocatalysis is considered asan important alternative approach for the direct conversion of methane into value-added chemicals, al-though many other innovative methods have been developed. This review highlights recent advances inelectrocatalytic conversion of methane to ethylene and methanol, two important chemicals. The electro-catalytic systems efficient for methane conversions are summarized with an emphasis on catalysts andelectrolytes. The effects of reaction conditions such as the temperature and the acid-base property of thereaction medium are also discussed, 展开更多
关键词 METHANE ELECTROCATALYSIS Selective conversion Value-added chemicals
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Improvement of Chemically-activated Luciferase Gene Expression Bioassay for Detection of Dioxin-Iike Chemicals 被引量:4
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作者 ZhangZR XuSQ 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第1期58-66,共9页
Objective To improve the chemically-activated luciferase expression (CALUX)bioassay for detection of dioxin-like chemicals (DLCs) based on the toxicity mechanisms ofDLCs. Method A recombinant vector was construc... Objective To improve the chemically-activated luciferase expression (CALUX)bioassay for detection of dioxin-like chemicals (DLCs) based on the toxicity mechanisms ofDLCs. Method A recombinant vector was constructed and used to transfect humanhepatoma (HepG2). The expression of this vector was 10-100 folds higher than that of pGL2used in previous experiments. The transfected cells showed aromatic hydrocarbon receptor(AhR)-meditated luciferase gene expression. The reliability of luciferase induction in thiscell line as a reporter of AhR-mediated toxicity was evaluated, the optimal detection timewas examined and a comparison was made by using the commonly used ethoxyresoufin-O-deethylase (EROD) activity induction assay. Result The results suggested that theluciferase activity in recombinant cells was peaked at about 4 h and then decreased to astable activity by 14 h after TCDD treatment. The detection limit of this cell line was0.11pmol/L, or 10-fold lower than in previous studies, with a linear range from 1 to 100pmol/L, related coefficient of 0.997, and the coefficient of variability (CV) of 15-30%.Conclusion The luciferase induction is 30-fold more sensitive than EROD induction, thedetection time is 68 h shorter and the detection procedure is also simpler. 展开更多
关键词 Dioxin-like chemicals LUCIFERASE Reporter gene TCDD CALUX
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Informational uncertainties of risk assessment about accidents of chemicals 被引量:2
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作者 ZHANG Yi-xian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期69-74,共6页
An analysis system of informational uncertainties for accidental risk assessment of chemicals is introduced. Statistical test methods and fuzzy sets method can do the quantitative analysis of the input parameters. The... An analysis system of informational uncertainties for accidental risk assessment of chemicals is introduced. Statistical test methods and fuzzy sets method can do the quantitative analysis of the input parameters. The uncerainties of the model can be used by quantitative compared method for the leakage accidents of chemicals. The estimation of the leaking time is important for discussing accidental source term. The uncertain analyses of the release accident for pipeline gas (CO) liquid chlorine and liquid propane gas (LPG) have been discussed. 展开更多
关键词 UNCERTAINTY risk assessment ACCIDENT chemicals pipeline gas liquid chlorine LPG
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Numerical Study on the Leakage and Diffusion Characteristics of Low-Solubility and Low-Volatile Dangerous Chemicals from Ship in Inland Rivers 被引量:3
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作者 Shuifen Zhan Mingchao Wang +4 位作者 Min Wang Qianqian Shao Zefang Zhang Wenxin Jiang Xuemin Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第4期217-235,共19页
Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is propos... Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is proposed in this paper.Geographic information,such as rivers and buildings in the model,is obtained through Google Earth and structures of rivers and buildings are described by Auto CAD.In addition,the Fluent is adopted to simulate the leakage and diffusion processes of the dangerous chemicals where the standard k-εmodel is used to calculate the turbulent flow.Considering the interaction between chemicals and water,the VOF method is used to describe the leakage,drift and diffusion process of dangerous chemicals groups on the water surface.Taking a section of the Yangtze River as an example,the leakage and diffusion processes from a ship carrying 3,000 tons of low-solubility and low-volatile dangerous chemicals are studied,and the characteristics of leakage and diffusion are analyzed in detail.During the simulation,the area of the maximum group of leaked dangerous chemicals reaches up to about 1800 m2,and the number reaches up to 45.Furthermore,the influence of density,viscosity,water velocity and leakage velocity on the leakage and diffusion processes is investigated in this paper. 展开更多
关键词 Inland rivers low-solubility and low-volatile dangerous chemicals leakage and diffusion VOF.
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Efficient production of chemicals from microorganism by metabolic engineering and synthetic biology 被引量:2
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作者 Yang Zhang Jing Yu +7 位作者 Yilu Wu Mingda Li Yuxuan Zhao Haowen Zhu Changjing Chen Meng Wang Biqiang Chen Tianwei Tan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期14-28,共15页
The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of syntheti... The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of synthetic biology and metabolic engineering,the use of renewable biomass raw materials for chemicals synthesis by constructing efficient microbial cell factories is a green way to replace traditional chemical catalysis and traditional microbial fermentation.This review mainly summarizes several types of bulk chemicals and high value-added chemicals using metabolic engineering and synthetic biology strategies to achieve efficient microbial production.In addition,this review also summarizes several strategies for effectively regulating microbial cell metabolism.These strategies can achieve the coupling balance of material and energy by regulating intracellular material metabolism or energy metabolism,and promote the efficient production of target chemicals by microorganisms. 展开更多
关键词 chemicals Synthetic biology Metabolic regulation Microbial cell factory
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Methodology and Application for Health Risk Classification of Chemicals in Foods Based on Risk Matrix 被引量:11
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作者 ZHOU Ping Ping LIU Zhao Ping +4 位作者 ZHANG Lei LIU Ai Dong SONG Yan YONG Ling LI Ning 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第11期912-916,共5页
The method has been developed to accurately identify the magnitude of health risks and provide scientific evidence for implementation of risk management in food safety.It combines two parameters including consequence ... The method has been developed to accurately identify the magnitude of health risks and provide scientific evidence for implementation of risk management in food safety.It combines two parameters including consequence and likelihood of adverse effects based on risk matrix.Score definitions and classification for the consequence and the likelihood of adverse effects are proposed.The risk score identifies the intersection of consequence and likelihood in risk matrix represents its health risk level with different colors:‘low',‘medium',‘high'.Its use in an actual case is shown. 展开更多
关键词 likelihood consequence intersection colors toxicity intake magnitude Medium judgment chemicals
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Effects of Temperature and Several Chemicals on Metabolic Changes During Dormancy Release in NJ72 Nectarine 被引量:2
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作者 YUANZhi-you LIXian-li +2 位作者 LILing-hao HANXing-guo YANTian-li 《Agricultural Sciences in China》 CAS CSCD 2003年第5期549-555,共7页
Poor, delayed and ununiform budbreak is a major problem for peaches in greenhouse. To clarify the mechanism of breaking bud dormancy in nectarines, the effect of temperature and three dormancy-breaking agents on metab... Poor, delayed and ununiform budbreak is a major problem for peaches in greenhouse. To clarify the mechanism of breaking bud dormancy in nectarines, the effect of temperature and three dormancy-breaking agents on metabolic changes during dormancy release in two-year old NJ72 nectarine (Prunus persica L. Batch) was investigated. The result showed temperature and chemicals affected the budbreak and the metabolism of NJ72 nectarine during dormancy. Endogeneous peroxide content in buds increased soon after low temperature treatment. Meanwhile, catalase activity was also shown to increase significantly at low temperature treatment, coincided with increase of the activity of peroxidase and superoxide dismutase. The rate of respiration in flower buds increased at low temperature during dormancy. The rate of the pentose phosphate pathway increased, while the rate of the Embden-Meyerhof pathway decreased and the rate of tricarboxlic acid cycle changed little. Glucose 6-phosphate dehydrogenase activity increased at low temperature during dormancy. At the same time we found an accumulation of peroxide after treatment with dormancy-breaking chemicals. In flower buds treated with dormancy-breaking agents, thiourea, KNO3 and NH4NO3, catalase activity was inhibited soon after treatment, whereas peroxidase activity increased, and the changes of superoxide dismutase remained little. In this study, it was found that the rates of respiration in flower buds increased by chemicals sprays during dormancy. The activity of glucose 6-phosphate dehydrogenase, the key enzyme in the pentose phosphate pathway (PPP), increased by spraying with dormancy-breaking agents, concomitantly with the activation of the pentose phosphate pathway. 展开更多
关键词 Prunus persica L. Batch DORMANCY TEMPERATURE chemicals
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Heterogeneous Catalysis for CO_(2) Conversion into Chemicals and Fuels 被引量:2
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作者 Dunfeng Gao Wanjun Li +2 位作者 Hanyu Wang Guoxiong Wang Rui Cai 《Transactions of Tianjin University》 EI CAS 2022年第4期245-264,共20页
Catalytic conversion of CO_(2)into chemicals and fuels is a viable method to reduce carbon emissions and achieve carbon neutrality.Through thermal catalysis,electrocatalysis,and photo(electro)catalysis,CO_(2)can be co... Catalytic conversion of CO_(2)into chemicals and fuels is a viable method to reduce carbon emissions and achieve carbon neutrality.Through thermal catalysis,electrocatalysis,and photo(electro)catalysis,CO_(2)can be converted into a wide range of valuable products,including CO,formic acid,methanol,methane,ethanol,acetic acid,propanol,light olefi ns,aromatics,and gasoline,as well as fi ne chemicals.In this mini-review,we summarize the recent progress in heterogeneous catalysis for CO_(2)conversion into chemicals and fuels and highlight some representative studies of diff erent conversion routes.The structure-performance correlations of typical catalytic materials used for the CO_(2)conversion reactions have been revealed by combining advanced in situ/operando spectroscopy and microscopy characterizations and density functional theory cal-culations.Catalytic selectivity toward a single CO_(2)reduction product/fraction should be further improved at an industrially relevant CO_(2)conversion rate with considerable stability in the future. 展开更多
关键词 CO_(2)conversion CO_(2)hydrogenation CO_(2)electroreduction chemicals Fuels
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Ionic liquid-based salting-out extraction of bio-chemicals 被引量:1
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作者 Jianying Dai Yaqin Sun Zhilong Xiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期185-193,共9页
Ionic liquids(ILs)are known as green solvents,and have been widely used in the dissolution and transformation of biopolymers,the extraction of bioactive compounds and metal ions,and the capture of SO2 or CO2.However,l... Ionic liquids(ILs)are known as green solvents,and have been widely used in the dissolution and transformation of biopolymers,the extraction of bioactive compounds and metal ions,and the capture of SO2 or CO2.However,less attention was given to the separation of bio-based chemicals,such as diols and organic acids.Bio-based chemicals can be efficiently separated by organic solvent-based salting-out extraction(SOE)from fermentation broths,while organic solvents are normally unfriendly to environment and process safety in commercialized production due to their toxicity or/and flammability.In recent years,the IL-based SOE system has been explored in the separation of bio-based chemicals as an alternative of organic solvent-based SOE system.In this review,the progress of IL-based SOE of biobased chemicals has been summarized,including the effect of ILs structure on the formation of aqueous two phases,and the influences of ILs structure and concentration,temperature and pH on the partition behaviors of target products and ILs as well as removal of impurities.Most of bio-based chemicals could be distributed into the IL-rich phase with high recovery,while the partition behaviors of bio-based chemicals are sometimes different from that in organic solvent-based SOE systems.Although the results of ILbased SOE are promising,further studies are still required in the increased selectivity of target products over by-products,recovery and recycling of ILs,and the separation between ILs and bio-based chemicals.Additionally,three kinds of integrated bioprocesses would be developed on basis of utilization of ILs as extractant for SOE,catalyst for condensation reaction and solvent for pretreatment of lignocellulose. 展开更多
关键词 Downstream processing BIOSEPARATION Ionic liquids Salting-out extraction Partition behavior Bio-based chemicals
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Boosting hydrogen and chemicals production through ethanol electro-reforming on Pt-transition metal anodes 被引量:1
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作者 Alberto Rodríguez-Gómez Fernando Dorado +1 位作者 Paula Sánchez Ana Raquel de la Osa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期394-406,I0011,共14页
The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particula... The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, Pt X/C electrocatalysts(where X corresponds to Cu, Co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane(PEM) cell configurations. Characterization results showed that incorporation of Ni and Co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and Cu-based electrocatalysts. Ethanol oxidation reaction(EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. Pt Co/C and Pt Ni/C exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30%(up to 1050 m A cm^(-2)) in the hydrogen production and chemical yields. On the other hand, Pt Ru/C results more advantageous for a lower potential interval(<0.85 V) promoting the acetic acid production despite sacrificing ethanol conversion. Pt Cu/C presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals(particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development. 展开更多
关键词 Ethanol electrochemical reforming Bimetallic anodic electrocatalysts PEM cell High current performance HYDROGEN chemicals production
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Endocrine disrupting chemicals in mixture and obesity,diabetes and related metabolic disorders 被引量:5
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作者 Brigitte Le Magueresse-Battistoni Emmanuel Labaronne +1 位作者 Hubert Vidal Danielle Naville 《World Journal of Biological Chemistry》 2017年第2期108-119,共12页
Obesity and associated metabolic disorders represent a major societal challenge in health and quality of life with large psychological consequences in addition to physical disabilities. They are also one of the leadin... Obesity and associated metabolic disorders represent a major societal challenge in health and quality of life with large psychological consequences in addition to physical disabilities. They are also one of the leading causes of morbidity and mortality. Although, different etiologic factors including excessive food intake and reduced physical activity have been well identified, they cannot explain the kinetics of epidemic evolution of obesity and diabetes with prevalence rates reaching pandemic proportions. Interestingly, convincing data have shown that environmental pollutants, specifically those endowed with endocrine disrupting activities, could contribute to the etiology of these multifactorial metabolic disorders. Within this review, we will recapitulate characteristics of endocrine disruption. We will demonstrate that metabolic disorders could originate from endocrine disruption with a particular focus on convincing data from the literature. Eventually, we will present how handling an original mouse model of chronic exposition to a mixture of pollutants allowed demonstrating that a mixture of pollutants each at doses beyond their active dose could induce substantial deleterious effects on several metabolic end-points. This proof-of-concept study, as well as other studies on mixtures of pollutants, stresses the needs for revisiting the current threshold model used in risk assessment which does not take into account potential effects of mixtures containing pollutants at environmental doses, e.g., the real life exposure. Certainly, more studies are necessary to better determine the nature of the chemicals to which humans are exposed and at which level, and their health impact. As well, research studies on substitute products are essential to identify harmless molecules. 展开更多
关键词 Endocrine disrupting chemicals Persistent organic pollutants PHTHALATES Bisphenol A Metabolic disorders Insulin resistance
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