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Recent advances in the biosynthesis of coumarin and its derivatives

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Green Chemical Engineering 2024年第2期5卷 150-154页

作者： Yusong zou Yuxi Teng Joy Li Yajun yan School of Chemical Materials and Biomedical EngineeringCollege of EngineeringThe University of GeorgiaAthensGA30602USA North Oconee High School BogartGA30622USA

Coumarin and its derivatives,presenting in many organisms(plants,fungi,and bacteria),are critical metabolites composed of fused benzene andα-pyrone *** unique biological and chemical properties,coumarin derivatives possess great technological potential in the agrochemicals,pharmaceuticals,food,and cosmetic *** increasing demand for coumarin derivatives accelerates the research in biological and chemical synthesis to provide stable and scalable sources of ***,the complex structures and unknown pathways have limited the progress in the biosynthesis of coumarin ***,we summarize recent developments and provide a detailed analysis of coumarin derivative biosynthetic pathways in different organisms.

关键词： Coumarin derivatives Biosynthetic pathways Biotransformation Metabolic engineering

Nanocrystalline WSe_(2)excels at high-performance anode for Na storage via a facile one-pot hydrothermal method

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Tungsten 2024年第1期6卷 248-258页

作者： Hai-yan.zou Lei Fang Gang Yu Dong Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and DevicesCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Changxing County Quality and Technology Supervision and Testing Center Huzhou 313100China

For the next large-scale energy storage systems,sodium-ion batteries(SIBs)with excellent electrochemical performance are ***,the exploration of anode materials with high specific capacity,fascinating cycling stability and rate capability is still *** transition metal dichalcogenides(TMDs),tungsten diselenide(WSe_(2))has been regarded as an effective anode material for SIBs and has been extensively studied,due to high theoretical capacity and unique twodimensional layered ***,nanocrystalline WSe_(2)is prepared by a facile one-pot hydrothermal *** with the micro-scale WSe_(2),benefiting from the high specific surface area of highly ordered nano-flake structures and short ion/electron transport paths,nanocrystalline WSe_(2)shows excellent electrochemical performance in Na *** 1000 cycles at a current density of 2 A·g^(-1),a high specific capacity of 264.4 mA·h·g^(-1)is still *** full cell matched with the Na_(3)V_(2)(PO_(4))_(3) cathode can deliver an excellent reversible specific capacity of 196.5 mA·h·g^(-1)after 100 cycles at 0.5 A·g^(-1).

关键词： Tungsten diselenide Transition metal dichalcogenides Hydrothermal Sodium-ion batteries Layered structure

Boosted sustained-release with iron-based MOF-derived mesoporouscarbon-spheres as a nitroimidazole drugs carrier

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Particuology 2024年第3期86卷 269-280页

作者： Danping Wu Jiaying zou Junyi Chen yan.Li Na Ma Wei Dai College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua321004China College of Life Sciences Zhejiang Normal UniversityJinhua321004China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China

Metal-organic framework(MoF)with a buildable internal structure has aroused great interest focus as self-sacrificing precursors of porous carbon(PC).However,as a drug carrier,the MOF-derived PC developed thus far are generally composed of irregular powder shape due to their crystalline nature,which consequently causing the cerebral infarction,cerebral thrombosis,and other blood *** this article,we propose a novel approach to constructing amorphous carbon microspheres(AcMs)by dis-torting the topological network through hydrothermal treatment precursors of MIL-101(Fe).Then,a distinctive MIL-101(Fe)-derived spherical porous carbons(MSPC)is achieved through high temperature calcination toward *** of the glucose initial concentration and hydrothermal treatment time on the sphericity of the as-prepared mesoporous MsPC were investigated in *** the loading capacities and sustained-release performances of nitroimidazole drugs over MsPC through simulation internal environment of human body at different pH values was systematically *** nitro-imidazole drugs loading rate and release time of MsPC are 10% and 17 h under preferred ***,the MSPC exhibited very low toxicity on Hela cells and 293T cells at the concentrations tested(10-800μg mL^(-1)).This study,therefore,supports the potential of the mesoporous carbon spheres as a carrierfor nitroimidazole drug delivery.

关键词： Ornidazole Metronidazole Carbon spheres Sustained-release performance Biocompatibility

Application of organic manure as a potential strategy to alleviate the limitation of microbial resources in soybean rhizospheric and bulk soils

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Journal of Integrative Agriculture 2024年第6期23卷 2065-2082页

作者： Zhimin Wu Xiaozeng Han Xu Chen Xinchun Lu Jun yan.Wei Wang Wenxiu zou Lei yan School of Resources and Environment Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081China Heilongjiang Academy of Agricultural Sciences Harbin 150086China

The development and vigor of soil microorganisms in terrestrial ecosystems are frequently constrained by the limited availability of essential elements such as carbon(C),nitrogen(N),and phosphorus(P).In this study,we investigated the impact of long-term application of varying levels of organic manure,low(7.5 Mg ha^(−1)yr^(−1)),moderate(15.0 Mg ha^(−1)yr^(−1)),and high(22.5 Mg ha^(−1)yr^(−1)),on the stoichiometry of enzymes and the structures of the microbial communities in soybean rhizospheric and bulk *** main goal of this research was to examine how soil microbial resource limitations in the rhizosphere respond to different long-term fertilization *** soil enzymatic activities were quantified,and the structure of the microbial community was assessed by analyzing phospholipid fatty acid *** compared to the bulk soil,the rhizospheric soil had significant increases in microbial biomass carbon(MBC),nitrogen(MBN),and phosphorus(MBP),with MBC increasing by 54.19 to 72.86%,MBN by 47.30 to 48.17%,and MBP by 17.37 to 208.47%.Compared with the unfertilized control(CK),the total microbial biomasses of the rhizospheric(increased by 22.80 to 90.82%)and bulk soils(increased by 10.57 to 60.54%)both exhibited increases with the application of organic manure,and the rhizospheric biomass was higher than that of bulk *** with bulk soil,the activities of C-,N-and P-acquiring enzymes of rhizospheric soil increased by 22.49,14.88,and 29.45%under high levels of organic manure,*** of vector length,vector angle,and scatter plots revealed that both rhizospheric and bulk soils exhibited limitations in terms of both carbon(C)and phosphorus(P)*** results of partial least-squares path modelling indicated that the rhizospheric soil exhibited a more pronounced response to the rate of manure application than the bulk *** varying reactions of rhizospheric and bulk soils to the extended application of organic manure underscore

关键词： enzymatic stoichiometry rhizosphere phospholipid fatty acids soybean organic manure

A novel optical emission spectroscopy method for diagnostics of contribution of different ionization mechanisms and flux of ions in different valences in discharge channel of a Hall thruster

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Chinese Journal of Aeronautics 2024年第4期37卷 294-307页

作者： yan.ei WANG Ximing ZHU Renqiu zou Shilin yan.Junwei JIA Zhongxi NING Daren YU School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Aerospace Plasma Propulsion Ministry of Industry and Information TechnologyHarbin 150001China Beijing Orient Institute of Measurement and Test Beijing 100094China Beijing Aerospace Long March Aircraft Research Institute Beijing 100076China

The mass application of Hall thrusters poses the need for a diagnostic method of ionization mechanism in the discharge channel to boost the iteration and optimization of thruster *** work presents an Optical Emission Spectroscopy (OES) method for diagnostics of the contribution of different ionization mechanisms and the flux of ions in different valences in the discharge channel of a Hall *** emission spectra in the discharge channel are analyzed by jointly utilizing a collisional-radiative model,an ionization-excitation model,and a flux-conservation *** is found that the intensities of some spectral lines can be converted into the reaction rates of collision processes,e.g.,electron-induced excitation and ionization *** latter can further be used to determine the evolutions of particle fluxes by utilizing the conservation law of *** novel method is demonstrated on a kilo-watt Hall *** evolutions of several parameters are determined using this method along the discharge channel,including the ionization rates of different mechanisms,particle fluxes,particle densities,and particle *** novel method can be further developed by being jointly utilized with spectral imaging and tomography techniques,enabling diagnostics of multi-dimensional distributions of the above-mentioned parameters in the discharge channel and near-field plume.

关键词： Hall thruster Optical emission spectroscopy Ionization mechanism Particle flux Divalent ion

In situ sulfur-doped mesoporous tungsten oxides for gas sensing toward benzene series

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Chinese Chemical Letters 2024年第7期35卷 502-507页

作者： Yu Deng yan.Liu Yonghui Deng Jinsheng Cheng Yidong zou Wei Luo State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan UniversityShanghai 200433China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China Henry-Fork School of Food Sciences Shaoguan UniversityShaoguan 512005China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Benzene series as highly toxic gases have inevitably entered human life and produce great threat to human health and ecological environment,and thus it is distinctly meaningful to monitor benzene series with quickly,real-time and efficient ***,novel sulfur-doped mesoporous WO_(3)materials were synthesized via classical in-situ solvent evaporation induced co-assembly strategy combined with doping engineering,which possessed highly crystallized frameworks,high specific surface area(40.9–63.8 m^(2)/g)and uniform pore size(~18 nm).Benefitting from abundant oxygen vacancy and defects via S-doping,the tailored mesoporous S/m WO_(3)exhibited excellent benzene sensing performance,including high sensitivity(50 ppm vs.48),low detection limit(ca.500 ppb),outstanding selectivity and favorable *** addition,the reduction of band gap resulted from S-doping promotes the carrier migration in the sensing materials and the reaction at the gas–solid sensing *** provides brand-new approach to design sensitive materials with multiple reaction sites.

关键词： Mesoporous materials Benzene series Tungsten oxides Sulfur doping Gas sensor

A thermal stress loading technique for large-sized hot dry rock mechanical tests

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Deep Underground Science and Engineering 2024年第3期3卷 326-337页

作者： Huiling Ci Bing Bai Hongwu Lei yan.zou Jianfeng Liu State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhanChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengduChina

Testing of large-sized specimens is becoming increasingly important in deep underground rock mechanics and *** traditional mechanical loading,stresses on large-sized specimens are achieved by large host frames and hydraulic pumps,which could lead to great ***-cost testing machines clearly always have great *** this study,a new approach is proposed using thermal expansion stress to load rock specimens,which may be particularly suitable for tests of deep hot dry rock with high *** is a different technical route from traditional mechanical loading through hydraulic *** the rock mechanics test system of hot dry rock that already has an investment in heating systems,this technology may reduce the cost of the loading subsystem by fully utilizing the temperature *** paper presents the basic principle and a typical design of this technical *** feasibility analysis is then conducted based on numerical *** some technical details still need to be resolved,the feasibility of this loading approach has been preliminarily confirmed.

关键词： deep rock engineering high-temperature and high-stress conditions hot dry rock large-sized model test thermal stress loading

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Difference in microstructural characteristics of stamp-charged coke and gravity-charged coke with approximate macroscopic performance

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Journal of Iron and Steel Research International 2024年第5期31卷 1050-1062页

作者： Chong zou Zheng-yan.Huang Jian-yun Li Bin Li Shi-wei Liu Yuan She School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710311ShaanxiChina Technical Center of Shandong Iron and Steel Co. Ltd.(Laiwu Branch)Jinan271104ShandongChina

The microstructural characteristics including optical texture,porosity and pore structure and chemical structure of stamp-charged coke(SCC)and gravity-charged coke(GCC)with similar conventional macro-indicators were investigated,and the properties including micro-strength,reactivity of coke matrix and that after alkali enrichment were comparatively studied by various characterization *** anisotropic structure of SCC is composed of high content of fine mosaic texture,while the content of medium mosaic texture,coarse texture and fibrous texture is *** statistical average shows that the fine mosaic average of SCC(24.89%)is 3.78 times the GCC average(6.58%),and the coarse mosaic average(1.24%)is only about 1/3 of the GCC average(3.43%).The porosity of SCC is lower than that of GCC,but tamping process does not lead to the fact that the number of closed pores of SCC is significantly lower than that of *** the structure of SCC is compact,its pore number is large and the pore wall is *** of coke with diameter less than 150 nm seem unaffected by tamping *** aromatic structure of SCC was less ordered than that of GCC,which was speculated to be related to the addition of more low metamorphic coal in *** microscopic strength and structural strength of SCC are lower than those of *** reactivity of coke matrix is affected by the specific surface area,but it is not the determining factor of its *** improvement in dissolution reactivity of coke after potassium enrichment is independent of coke type.

关键词： Stamp-charged coke Optical texture Porosity Microstructure Reactivity

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yan. Yin Qi-chi Le yan.chao Jiang Da-zhi Zhao Qi-yu Liao Qi zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy