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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： Yanfei 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

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Study on frictional behavior of SiC_(f)/SiC composite clad tube clamping condition under nuclear irradiation

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Friction 2024年第5期12卷 919-938页

作者： Chenglong XIAO Liangliang SHEN Tianqi zhu Jianbo TANG ximing XIE Xinyu FAN Jian XU Zhiying REN School of Mechanical Engineering Zhejiang University of TechnologyHangzhou310023China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China State Key Laboratory of Fine Chemicals Liaoning High-Performance Polymer Engineering Research CenterSchool of Chemical EngineeringDalian University of TechnologyDalian116024China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China School of Computer Science and Technology Shandong UniversityQingdao266237China Aviation Industry Corporation of China Ltd.Beijing100028China

Silicon carbide fiber reinforced silicon carbide matrix(SiC_(f)/SiC)composite is the key cladding material of nuclear fuel,which determines the safety and reliability of nuclear fuel storage and *** replacement of its storage and transportation scenario needs to be completed by the manipulator,but the application of SiC_(f)/SiC wear,fracture,and nuclear leakage in the snatching process of brittle-flexible-rigid contact in the irradiation environment has been seriously restricted due to unclear understanding of the damage ***,the effects of irradiation dose and clamping load on the friction characteristics of the contact interface between SiC_(f)/SiC clad tube are studied in this paper,and the effects of irradiation parameters and clamping force on the static friction coefficient of the contact interface between the clad tube and flexible nitrile are *** on the Greenwood-Williamson tribological model,a numerical model of the shape and structure of the contact micro-convex at the micro-scale of the clamping interface is constructed by introducing the multi-surface integral,and finally verified by *** research results show that there is a unique“Irradiation suppression zone”under the clamping condition of SiC_(f)/SiC cladding tube under the nuclear irradiation environment,and the growth of static friction coefficient slows down until stagnates after irradiation reaches a certain extent(600 kGy),and there will be a decline when the irradiation dose continues to increase,among which the clamping force of 15.2 N within the irradiation interval of 1,000 kGy can meet the safety of nuclear environment *** results of this paper can provide an important theoretical basis and application guidance for the safe operation of SiC_(f)/SiC cladding tubes in the storage and transportation clamping process.

关键词： SiC_(f)/SiC Clad tube nuclear irradiation conditions Greenwood-Williamson tribological model multi-surface integral

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Preliminary Study of a Hybrid Helicon-ECR Plasma Source

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Plasma Science and Technology 2016年第8期18卷 832-836页

作者： A.M.HALA L.OKSUZ zhu ximing The National Center for Applied Physics Material Science Research InstituteKing Abdul Aziz City for Science and Technology(KACST) Süleyman Demirel University Science and Literature FacultyPhysics Department Institute for Plasma and Atomic Physics Ruhr University

A new type of hybrid discharge is experimentally investigated in this work. A helicon source and an electron cyclotron resonance（ECR） source were combined to produce plasma. As a preliminary study of this type of plasma, the optical emission spectroscopy（OES） method was used to obtain values of electron temperature and density under a series of typical conditions. Generally,it was observed that the electron temperature decreases and the electron density increases as the pressure increased. When increasing the applied power at a certain pressure, the average electron density at certain positions in the discharge does not increase significantly possibly due to the high degree of neutral depletion. Electron temperature increased with power in the hybrid *** mechanisms of these preliminary observations are discussed.

关键词： helicon plasma ECR hybrid discharge

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Diagnostic and modelling investigation on the ion acceleration and plasma throttling effects in a dualemitter hollow cathode micro-thruster

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Chinese Journal of Aeronautics 2021年第12期34卷 85-98页

作者： Zhongxi NING Chenguang LIU ximing zhu Yanfei WANG Bingjian AN Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Hollow cathode discharges are widely used as neutralizers for the electric propulsion systems and recently developed into micro-thrusters for the small *** this work,a dualemitter hollow cathode thruster is developed,which can be operated in two different modes—the neutralizer mode and the micro-thruster *** characterizing this kind of new device,the Langmuir probe,Faraday probe,and retarding potential analyzer are used to determine the electron temperature,electron density,ion flux,and ion energy distribution *** operating parameters,including the thrust,and specific impulse,are also measured.A two-dimensional self-consistent extended fluid model is employed to calculate the spatial distribution of plasma parameters and the fluid field of electrons in the region around the *** comparing the diagnostic and modelling results,it is found that the change in the electric field and ionization zone is the essential reason for the different performances of the device in the neutralizer and micro-thruster *** in the electric field leads to an ion acceleration effect in the micro-thruster mode;moving of the ionization zone raises the plasma pressure in the orifice region of the hollow cathode,and thus leads to enhanced plasma throttling and gas expanding *** analyzing the above mechanisms,the possible methods for improving this kind of hollow cathode micro-thruster are discussed.

关键词： Extended fluid model Hollow cathodes Micro-thruster Plasma contactor Plasma throttling effect

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Recent advances in core-shell organic framework-based photocatalysts for energy conversion and environmental remediation

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Journal of Energy Chemistry 2024年第8期95卷 168-199,I0004页

作者： Qibing Dong ximing Li Yanyan Duan Qingyun Tian Xinxin Liang Yiyin zhu Lin Tian Junjun Wang Atif Sial Yongqian Cui Ke Zhao Chuanyi Wang School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi’an 710021ShaanxiChina Guangdong Engineering Technology Research Center for Environmental Purification and Functional Materials Guangzhou Institute of Industrial IntelligenceGuangzhou 511400GuangdongChina Jiangxi Key Lab of Flexible Electronics Flexible Electronics Innovation InstituteJiangxi Science and Technology Normal UniversityNanchang 330013JiangxiChina Helmholtz-Zentrum Berlin für Materialien und Energie Kekuléstraße 512489 BerlinGermany

Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy *** a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and *** existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF ***,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@***,there is an urgent need for a comprehensive review encompassing these three types of core-shell *** on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental ***,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were ***,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are ***,the main challenges and development prospects of core-shell organic framework photocatalysts were *** review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.

关键词： Organic framework Core-shell structure Photocatalysis Energy conversion Environmental remediation

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Experimental investigation on upstream and downstream discharges in airflows

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Plasma Science and Technology 2018年第12期20卷 56-64页

作者：周德胜唐井峰朱悉铭于达仁张潮海 School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001People's Republic of China Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of TechnologyHarbin 150001People's Republic of China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China

Dielectric barrier discharge has widely used in airflow control, ignition and combustion, and other applications; the influence of airflow on dielectric barrier discharge is of extensive concern. Previous studies demonstrate that the discharge becomes more uniform and the discharge intensity decreases with increasing of airflow velocity. In this study, we adopt a discharge cell construction with upstream and downstream structure and study the discharge states and intensities. The experimental results demonstrate that within a specific range of airflow speed, the upstream discharge intensity is decreased, and the downstream discharge intensity is enhanced. The physical basis for this phenomenon is proposed as follows： Within a pulse interval time, some particles, such as charged and metastable particles produced by the upstream discharge, could be transported to the downstream region. The concentration of particles in the downstream region is increased, and these particles play a pre-ionization role in the downstream discharge, the intensity of the downstream discharge is enhanced. Further, factors such as the pulse frequency and the distance between electrodes are discussed in detail, along with the conditions for enhancing downstream discharge intensity.

关键词： atmospheric pressure discharge dielectric barrier discharge airflow

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Peroxisome proliferator-activated receptors gama ameliorates liver fibrosis in non-alcoholic fatty liver disease by inhibiting TGF-β/Smad signaling activation

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Frigid Zone Medicine 2024年第1期4卷 12-22页

作者： Qingwei Zhang Wenjie Zhao Zeqi Sun Xinxin Dong Liwei zhu Zhen Zhang ximing Chen Yingying Hu Menghan Du Jiamin Li Yong Zhang Department of Pharmacology College of Pharmacyand Department of Cardiologythe Second Affiliated HospitalHarbin Medical UniversityHarbin 150081China Department of Pharmacology College of PharmacyHarbin Medical UniversityHarbin 150081China The State Key Laboratory of Frigid Zone Cardiovascular Diseases(SKLFZCD) and the Key Laboratory of Cardiovascular Medicine ResearchMinistry of EducationHarbin 150081China Research Unit of Noninfectious Chronic Diseases in Frigid Zone Chinese Academy of Medical Sciences2019RU070Harbin 150081China

Background:Nonalcoholic fatty liver disease(NAFLD)is a chronic condition characterized by a progressive decline in liver function,leading to disruptions in liver integrity and metabolic function,resulting in lipid deposition and excessive accumulation of extracellular matrix(ECM).The pathogenesis of NAFLD is complex and not yet fully understood,contributing to the absence of specific therapeutic *** proliferator-activated receptor gamma(PPARγ)is a ligand-activated transcription factor pivotal in regulating lipid and glucose ***,the impacts of PPARγon NAFLD remains insufficiently ***,this study aimed to investigate the role of PPARγin NAFLD and its underlying molecular ***:Chemical detection kits were utilized to quantify collagen content,alanine aminotransferase(ALT),and aspartate aminotransferase(AST)level *** real-time polymerase chain reaction(qRT-PCR)was employed to assess alterations in extracellular matrix-related genes and inflammatory response genes in liver tissue and HepG2 cells,while western blotting was conducted to analyze the levels of both PPARγand the TGF-β/Smad signaling ***:Our findings unveiled significantly reduced PPARγexpression in a rat model of NAFLD,leading to subsequent activation of the TGF-β/Smad signaling ***,PPARγactivation effectively mitigated NAFLD progression by inhibiting inflammation and fibrosis-related gene expression and collagen *** a cellular level,PPARγactivation was found to inhibit the expression of extracellular matrix-related genes such as matrix metalloproteinase 2(MMP2)and matrix metalloproteinase 9(MMP9),along with inflammatory response genes interleukin(IL)-1βand ***,PPARγactivation led to a significant decrease in the levels of ALT and *** the molecular level,PPARγnotably down-regulated the TGF-β/Smad signaling pathway,which is known to promote liver ***:These groundbre

关键词： NAFLD PPARγ TGF-β/Smad liver fibrosis

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THE EFFECT OF FEEDING PATTERNS IN PREGANCY ON THE PERFORMANCE OF SOWS

THE EFFECT OF FEEDING PATTERNS IN PREGANCY ON THE PERFORMANC...

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面向21世纪的动物科学与动物医学国际研讨会

作者： zhu ximing Institute of Animal Science CAAS Beijing 100094

＜正＞Unlike other countries（see NRC（1998） and ARC（1981））, in China, the pattern of feed distribution during sows’ pregnancy has been recommended as "low followed by high", rather than constant level throughout pregnancy. The object of these two experiments was to compare the two feeding pattems during pregnancy, and the effects of these patterns on sows’ body composition and reproductive traits were examined. Experiment 1.27 Beijing Black gilts were used for two parities. The same pregnancy diet was provided for all the sows, which contented 10.25 MJ DE, 139.2g CP, 5g Lysine, 105.6g

关键词： sow feeding pattern pregnancy milk

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Atmospheric pressure pulsed modulated arc discharge plasma

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Plasma Science and Technology 2023年第12期25卷 57-62页

作者：李寄唐井峰张浩然王璐纪添源于达仁朱悉铭 School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Direct-current(DC)arc plasma has great application values in the field of the chemical industry,but it has the problem of low energy *** the requirement for improving the energy efficiency of the arc,this paper proposes a unique method of pulsed modulated arc(PMA).This method uses high-frequency pulses and reduces the arc current to improve the control of electron *** electrical characteristics,optical characteristics and products are *** test results show that during the PMA process,all of the experimental results which include voltage,current and light will significantly *** results are analyzed from the perspective of functionality,repeatability and energy *** analysis results show that although the PMA method does not show good parameter consistency,it has potential application prospects because it increases the energy conversion rate by 4.5%and 8%from the perspective of light and products,respectively.

关键词： experimental research atmospheric pressure plasma DC arc PMA

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化学处理的高强度钢氢损伤及缺口强度研究

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热加工工艺 2013年第16期42卷 91-93页

作者：祝溪明沈阳职业技术学院辽宁沈阳110045

采用缺口试样慢拉伸试验研究了高强度钢在镀铬和电解酸洗后的断裂行为及其吸氢、放氢规律。结果表明,高强度结构钢经电解酸洗和镀铬后都有显著渗氢,且镀铬后的渗氢量高于电解酸洗;镀铬渗入的氢经180℃去氢处理后仍有1.5～3.0ml/100g的... 详细信息

采用缺口试样慢拉伸试验研究了高强度钢在镀铬和电解酸洗后的断裂行为及其吸氢、放氢规律。结果表明,高强度结构钢经电解酸洗和镀铬后都有显著渗氢,且镀铬后的渗氢量高于电解酸洗;镀铬渗入的氢经180℃去氢处理后仍有1.5～3.0ml/100g的残存量,残存氢的多少与钢种和组织状态有关,高锰钢、硅锰钢和铬锰钢的存氢量高于铬镍钢;电解酸洗或镀铬渗入的氢与残余应力相作用,导致材料产生氢损伤及钢的缺口强度大幅降低。

关键词：高强度结构钢镀铬电解酸洗渗氢氢损伤缺口强度

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