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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi jia Shuai-kang zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Nitrate Leaching in an Irrigated Wheat-Maize Rotation Field in the North China Plain

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Pedosphere 2005年第2期15卷 196-203页

作者： zhangYu-Ming HUChun-Sheng zhangjia-bao CHENDe-Li LIXiao-Xin InstituteofGeneticandDevelopmentalBiology ChineseAcademyofSciencesShijiazhuang050021（China） InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China） DepartmentofResourceManagementandHorticulture InstituteofLandandFoodResourcetheUniversityofMelbourneParkville3052Victoria（Australia）

Soil water deep drainage and nitrate (NO-3) leaching losses below the root zone were investigated in a 1 ha wheat-maize rotation field under traditional agricultural management that local farmers generally follow in the North China Plain, using the soil water balance method and NO3-N concentration in suction samples. Water drainage, and NO3-N distribution and leaching losses exhibited pronounced spatial and temporal variability. Soil water deep drainage and NO3-N leaching loss mostly occurred during the sum…

关键词： deep drainage nitrate leaching soil water

Tuning Synaptic Connections Instead of Weights by Genetic Algorithm in Spiking Policy Network

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Machine Intelligence Research 2024年第5期21卷 906-918页

作者： Duzhen zhang Tielin zhang Shuncheng jia Qingyu Wang Bo Xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China Institute of Automation Chinese Academy of Sciences(CAS)Beijing100190China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of Sciences(CAS)Shanghai200031China

Learning from interaction is the primary way that biological agents acquire knowledge about their environment and *** deep reinforcement learning(DRL)explores a computational approach to learning from interaction and has made significant progress in solving various ***,despite its power,DRL still falls short of biological agents in terms of energy *** the underlying mechanisms are not fully understood,we believe that the integration of spiking communication between neurons and biologically-plausible synaptic plasticity plays a prominent role in achieving greater energy *** this biological intuition,we optimized a spiking policy network(SPN)using a genetic algorithm as an energy-efficient alternative to *** SPN mimics the sensorimotor neuron pathway of insects and communicates through event-based *** by biological research showing that the brain forms memories by creating new synaptic connections and rewiring these connections based on new experiences,we tuned the synaptic connections instead of weights in the SPN to solve given *** results on several robotic control tasks demonstrate that our method can achieve the same level of performance as mainstream DRL methods while exhibiting significantly higher energy efficiency.

关键词： Spiking neural networks genetic evolution bio-inspired learning agent&cognitive architectures robotic control

Boosting high-rate Li-ion storage properties by La(Ⅲ)ion doping in spinel(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)high-entropy oxide anode

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Journal of Advanced Ceramics 2024年第6期13卷 769-779页

作者： Shijie Chen Mengfan bao Yanggang jia Pengpeng Wang Dan Wei Yuhuan Guo Jie Tan Aiqin Mao Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa’anshan 243032China Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials(Anhui University of Technology) Ministry of EducationMa’anshan 243032China

The present work aims to create lattice distortion and optimize the surface oxygen vacancy(OV)concentration in a model spinel(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)high-entropy oxide(HEO)through a heteroatom La^(3+)doping *** demonstrated,La^(3+)with a large radius can be doped successfully into the spinel lattice of(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4),thereby not only causing lattice distortion to increase oxygen vacancies but also refining crystalline grains and improving the specific *** with the(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)anode,the(La_(0.01)CoCrFeMnNi)_(3/5.01)O_(4) anode with moderate doping exhibits excellent cycling performance(1228 mAh·g^(−1)after 400 cycles at 0.2 A·g^(−1))and yields an increase of 75%rate capability at 3 A·g^(−1)(420 mAh·g^(−1)at 3 A·g^(−1)).The desirable kinetic transport of electrons and diffusion of Li+within the moderately La^(3+)-doped anode and the synergistic interfacial pseudocapacitive behavior satisfy the redox reaction at a high rate,thus increasing rate capability.

关键词： lithium-ion battery(LIB) anode lattice distortion high-entropy oxide(HEO) high-rate performance La^(3+)doping oxygen vacancy(OV)

Emerging WS_(2)/WSe_(2)@graphene nanocomposites: synthesis and electrochemical energy storage applications

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Rare Metals 2024年第1期43卷 1-19页

作者： Yu-Meng Gao Yong Liu Kai-jia Feng Jun-Qing Ma Ying-Jie Miao Bin-Rui Xu Kun-Ming Pan Osaka Akiyoshi Guang-Xin Wang Ke-Ke zhang Qiao-bao zhang National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan Key Laboratory of Non-Ferrous Materials Science and Processing TechnologySchool of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471023China Provincial and Ministerial Co-Construction of Collaborative School of Electrical Engineering Henan University of Science and TechnologyLuoyang 471023China Biomaterials Laboratory Faculty of EngineeringOkayama UniversityTsushima-NakeOkayama-Shi 700-8530Japan Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China Fujian Key Laboratory of Surface and Interface Engineering for High Performance Materials Xiamen UniversityXiamen 361005China

In recent years, tungsten disulfide(WS_(2)) and tungsten selenide(WSe_(2)) have emerged as favorable electrode materials because of their high theoretical capacity, large interlayer spacing, and high chemical activity;nevertheless, they have relatively low electronic conductivity and undergo large volume expansion during cycling, which greatly hinder them in practical applications. These drawbacks are addressed by combining a superior type of carbon material, graphene, with WS_(2) and WSe_(2) to form a WS_(2)/WSe_(2)@graphene *** materials have received considerable attention in electro-chemical energy storage applications such as lithium-ion batteries(LIBs), sodium-ion batteries(SIBs),and supercapacitors. Considering the rapidly growing research enthusiasm on this topic over the past several years, here the recent progress of WS_(2)/WSe_(2)@graphene nanocomposites in electrochemical energy storage applications is summarized. Furthermore, various methods for the synthesis of WS_(2)/WSe_(2)@graphene nanocomposites are reported and the relationships among these methods, nano/microstructures, and electrochemical performance are systematically summarized and discussed. In addition, the challenges and prospects for the future study and application of WS_(2)/WSe_(2)@graphene nanocomposites in electrochemical energy storage applications are proposed.

关键词： WS_(2)/WSe_(2)@graphene nanocomposites Liion batteries(LIBs) Na-ion batteries(SIBs) Supercapacitors Electrochemical performance

Heat dissipation of carbon shell in ZrC-SiC/TaC coating to improve protective ability against ultrahigh temperature ablation

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Journal of Advanced Ceramics 2024年第7期13卷 1080-1091页

作者： Yuyu zhang Xuemeng zhang Hongkang Ou Bozhe Wang jia Sun Qiangang Fu Science and Technology on Thermostructural Composite Materials Laboratory Shaanxi Key Laboratory of Fiber Reinforced Light-Weight CompositesNorthwestern Polytechnical UniversityXi’an 710072China System Design Institute of Hubei Aerospace Technology Academy Wuhan 430040China

To efficiently decrease ablation heat accumulation and improve the ability of ZrC-SiC/TaC coatings to protect carbon/carbon(C/C)composites,a thermally conductive nanonetwork with a ceramic@carbon core-shell structure was designed and ***-derived SiC/TaC with a graphene carbon shell was synthesized and introduced into a ZrC coating by supersonic atmospheric plasma spraying(SAPS).Graphene shell paths increased the heat transfer capability by lowering the surface temperature to approximately 200℃during oxyacetylene *** heat dissipation of the graphene shell in the ZrC-SiC/TaC@C coating reduced the volatilization of low-melting-point phases and delayed the sintering of ZrO_(2) ***,the graphene shell in ZrC-SiC/TaC@C coating decreased the mass and linear ablation rates by 91.4%and 93.7%compared to ZrC-SiC/TaC coating,*** work provided a constructive idea for improving the ablation resistance of the coatings by incorporating carbon nanomaterials as a function of heat dissipation.

关键词： carbon/carbon(C/C)composites carbon nanomaterials core-shell structure polymer-derived ceramic(PDC) ablation resistance

Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-Shuo bao Zi-Wei He Wen-Jing Xiao jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

Clinical evaluation of serum antimitochondrial antibody-negative primary biliary cirrhosis

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Hepatobiliary & Pancreatic Diseases International 2004年第2期3卷 288-291页

作者： Fu-Kui zhang, Ji-Dong jia and bao-En Wang Beijing, China Liver Research Center, Beijing Friendship Hospital, Capital University of Medical Sciences, Beijing 100050 , China Liver Research Center Beijing Friendship Hospital Capital University of Medical Sciences Beijing 100050 China. frankliver@***

BACKGROUND: Primary biliary cirrhosis (PBC) is cha- racterized by frequent presence of antimitochondrial anti- bodies (AMAs). The sensitivity and specificity of AMA for PBC are both greater than 90%-95%, so the presence of AMA in serum is the major hallmark in PBC. However, it has long been recognized that in 5%-10% of patients the clinical, biochemical and histological features are diagnos- tic for PBC, but their sera are consistently tested negative for AMA/AMA-M2. This study aimed to evaluate whether the presence of AMA alters the clinical, serological and his- tological features of the disease. METHODS: Clinical data of 70 patients clinically and/or histologically diagnosed with PBC were reviewed. AMA- negative and AMA-positive patients were compared in terms of clinical, biochemical, immunological and histo- logical features. RESULTS: At presentation, 11 patients were serum AMA/ AMA-M2 negative. At the initial visit, AMA-negative and AMA-positive patients were similar in terms of age, sex, clinical manifestations, liver biochemistries and histological findings. The mean level of serum immunoglobulin M (IgM) was significantly lower in AMA-negative PBC pa- tients than in AMA-positive PBC patients (2851±1418 mg/L vs 6361 ±4928 mg/L, P =0.033). Serum antinuclear anti- bodies ( ANA) and/or smooth muscle antibodies ( SMA) were more frequently positive in the AMA-negative PBC patients than in the AMA-positive patients (81.8% vs 40.7%, P =0.031). CONCLUSION: AMA-negative PBC patients are characte- rized by relatively lower levels of serum IgM and a higher prevalence of serum ANA/SMA and are not associated with substantial differences in the clinical, biochemical and histo- logical spectrum of the disease.

关键词： primary biliary cirrhosis antimitochondrial antibody antinuclear antibody immunoglobulin M

Targeted mutations of BnPAP2 lead to a yellow seed coat in Brassica napus L.

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Journal of Integrative Agriculture 2024年第2期23卷 724-730页

作者： Wei Huang Ruyu jiao Hongtao Cheng Shengli Cai jia Liu Qiong Hu Lili Liu bao Li Tonghua Wang Mei Li Dawei zhang Mingli Yan Hunan Research Center of Heterosis Utilization in Rapeseed/Crop Research Institute Hunan Academy of Agricultural SciencesChangsha 410125China Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization/School of Life and Health Science Hunan University of Science and TechnologyXiangtan 411201China Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs/Oil Crops Research InstituteChinese Academy of Agricultural SciencesWuhan 430062China

The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica *** the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked *** staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed *** and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic *** broad suppression of these genes might hinder proanthocyanidin accumulation during seed development,and thereby causing the yellow seed trait in *** results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.

关键词： yellow seed BnPAP2 proanthocyanidins CRISPR/Cas9

Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor

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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： jianfei WEI Silong zhang Jingying ZUO Xin LI jiang QIN Wen bao School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation