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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1056-1060页

作者： liu renjie YIN Lu ZHOU Yichun Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China

The bifacial n-PERT(Passivated Emitter Rear Totally diffused)solar cells were fabricated using a simplified process in which the activation of ion-implanted phosphorus and boron diffusion were performed simultaneously in a high-temperature *** further efficiency improvement,the rear side doping level was regulated by applying two different implantation doses and the chemical etching step of boron rich layer(BRL)was added,and their effects on cell performance were *** solar cells average efficiency reaches 20.35%with a bifaciality factor of 90%by optimizing rear side doping level,which can be explained by the decrease of Auger *** it is further enhanced to 20.74%by removing the front side BRL due to the improvement of surface passivation and bulk *** improved fabrication process possesses the advantages of low complexity and cost and high cell efficiency and bifaciality factor which could provide a promising way to the commercial production of bifacial n-PERT solar cells.

关键词： n-PERT solar cells ion implantation diffusion bifacial structure

Cobalt catalysts for Fischer–Tropsch synthesis： The effect of support,precipitant and pH value

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Chinese Journal of Chemical Engineering 2018年第4期26卷 747-752页

作者： zhenhua li mengyao si li xin renjie liu runxue liu jing lü Key Lab for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

In this report,Co-based catalysts supported on ZnO,Al_2O_3 and ZrO_2 as well as the ZrO_2 derived from different precipitants and different pH values were prepared by co-precipitation *** catalytic Fischer–Tropsch synthesis(FTS)performance was investigated in a fixed-bed *** results revealed that Co catalyst supported on ZrO_2 exhibited better FTS catalytic performance than that supported on ZnO or Al_2O_*** the Co/ZrO_2catalyst,different precipitants showed the following an activity order of NaOH>Na_2CO_3>NH_4OH,and the best pH value is *** catalysts were characterized by N_2adsorption–desorption,XRF,XRD,H_2-TPR,H_2-TPD and *** was found that the main factor affecting the CO conversion of the catalyst was the amounts of low-temperature active adsorption ***,the selectivity of C_5^+hydrocarbons had a positive relationship with the peak temperature of the weak hydrogen adsorption *** higher the peak temperature,the higher the C_5^+selectivity is.

关键词： Fischer–Tropsch synthesis Co-precipitation Carbon monoxide Hydrogenation ZrO2

Numerical and experimental research on annular crossed cable-truss structure under cable rupture

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 557-569页

作者： liu renjie Li Xiongyan Xue Suduo Marijke Mollaert Ye Jihong Key Laboratory of Urban Security and Disaster Engineering of MOE Beijing University of Technology Department of Architectural Engineering Vrije Universiteit Brussel School of Mechanics & Civil Engineering China University of Mining and Technology

The Annular Crossed Cable-Truss Structure（ACCTS） is a new type of Tensile Spatial Structure with a configuration suitable to cover large-span stadiums. Its configuration has potential to perform well in resisting disproportionate collapse. However, its disproportionate collapse resistance hasn＇t yet been analyzed in depth. In this study, numerical and experimental research was carried out to investigate the performance of ACCTS under cable rupture. The numerical analysis was done for ten cable-rupture plans using LS-DYNA（explicit method） and the experimental test on an ACCTS with a diameter of 17.15 m was performed for three cable-rupture plans. It is concluded that, while deflections increase with the number of removed cables, an ACCTS does not undergo a disproportionate collapse and it provides a promising structural concept for tensile spatial structures.

关键词： tensile spatial structure annular tensile cable-truss structure disproportionate collapse

Sulfur-resistant methanation over MoO_3/CeO_2–ZrO_2 catalyst: Influence of Ce-addition methods

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Journal of Energy Chemistry 2019年第1期28卷 31-38页

作者： Zhaopeng liu Yan Xu Zhenhua Li Baowei Wang Weihan Wang Xinbin Ma renjie liu Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University

In this paper, Ce_(0.2)Zr_(0.8)O_2 composite supports were prepared by different Ce-addition methods including impregnation of cerium(CeZr-imp), impregnation of citric acid and cerium(CeZr-CA) simultaneously and deposition precipitation method(CeZr-DP), respectively. The as-prepared supports were applied to prepare 10 wt% MoO_3/Ce_(0.2)Zr_(0.8)O_2 catalysts for sulfur-resistant methanation. The N_2 adsorption/desorption,X-ray diffraction(XRD), Raman spectroscopy(RS), X-ray photoelectron(XPS), temperature-programmed reduction by hydrogen(H_2-TPR) were undertaken to get textural properties, morphological information and structures of the catalysts. The results showed that Mo O_3 was highly dispersed on the surface of these three supports and Ce was mostly of coexisted in Ce^(4+)/Ce^(3+) redox pairs. Compared with Mo/CeZrimp, the CO conversion increased by 10% and 15% for Mo/CeZr-CA and Mo/CeZr-DP, respectively. This was mainly attributed to the larger specific surface area, Ce^(3+) concentration and content of active MoS_2 on the surface of catalysts.

关键词： Sulfur-resistant methanation Ce introducing methods Reducible Ce^3+ Synthetic natural gas Active MoS2

Novel Method for Preparing a Carbon Nanotube-Supported Cobalt Catalyst for Fischer–Tropsch Synthesis:Hydrogen Dielectric-Barrier Discharge Plasma

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Transactions of Tianjin University 2017年第1期23卷 20-25页

作者： Zhenhua Li Runxue liu renjie liu Weihan Wang Jing Lv Key Lab for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyCollaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Tianjin 300072China

Hydrogen dielectric-barrier discharge (H2-DBD) plasma was successfully used to prepare carbon nanotubes (CNTs)-supported cobalt (Co) catalyst. The H2-DBD plasma treatment simultaneously decomposed and reduced the cobalt precursor at a lower temperature and in a shorter time than the conventional method (calcination and hydrogen reduction). It is considered that the H2-DBD plasma method can remarkably decrease the amount of energy input compared to traditional methods used to prepare the Co-based catalyst in Fischer-Tropsch synthesis (FTS). Results showed that the Co catalyst prepared by H2-DBD plasma had an equivalent catalytic performance for FTS as that prepared using the conventional method in calcination and hydrogen reduction, thereby determining that H2-DBD plasma was an effective alternative treatment for preparing the Co/CNTs catalyst for FTS. This technology will provide a new strategy for preparing catalysts in other catalysis processes.

关键词： Fischer-Tropsch synthesis H2 dielectric-barrier discharge Plasma Cobalt Carbon nanotubes

Study on high efficient electric discharge milling of silicon carbide ceramic with high resistivity

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Chinese Science Bulletin 2008年第20期53卷 3247-3254页

作者： JI renjie liu YongHong YU LiLi LI XiaoPeng DONG Xin College of Electromechanical Engineering China University of Petroleum Dongying 257061 China

A new method which employs a group pulse power supply for electric discharge milling of the silicon carbide ceramic with the resistivity of 500 Ω·cm is presented. Due to the good machining stability and high pulse utilization, the material removal rate (MRR) can reach 72.9 mm3/min. The effects of high-frequency pulse duration, high-frequency pulse interval, peak voltage, peak current, polarity, rotate speed and group frequency on the process performance have been investigated. Also the EDMed surface microstructure is examined with a scanning electron microscope (SEM), an X-ray diffraction (XRD), an energy dispersive spectrometer (EDS) and a micro hardness tester. The results show that the conditions of smaller high-frequency pulse duration and pulse interval, higher peak voltage and peak current, and positive tool polarity are suitable for machining the SiC ceramic. The optimal rotate speed is 1090 r/min and the preferable group frequency is 730 Hz. In addition, there is a small quantity of iron on machined surface when machining with steel electrode. The average grain size of the EDMed surface is smaller than that of the unprocessed, and the micro hardness of machined surface is superior to that of the unprocessed.

关键词：碳化硅陶瓷电阻系数放电加工制备方法

Electrolyte additive maintains high performance for dendrite-free lithium metal anode

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Chinese Chemical Letters 2020年第5期31卷 1217-1220页

作者： Manshu Zhang renjie liua Zekun Wang Xiyuan Xing Yangai liu Bingbing Deng Tao Yang Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes.National Laboratory of Mineral Materials School of Materials Science and Technology.China University of GeosciencesBeijing 100083China Shanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials Xi'an Key Laboratory of Green Processing for Ceramic materialsSchool of Material Science and EngineeringShaanxi University of Science and TechnologyXi'an 710021China College of Materials&Environmental Engineering Hangzhou Dianzi University.Hangzhou 310036China

Because of their high capacity and low potential,lithium metal anodes are considered to be promising candidates for next generation electrode ***,the safety concerns and limited cycling life associated with uncontrollable dendrite growth hamper practical *** this work,the acidified cellulose ester,which is a mixed fiber microporous membrane film,was used as a novel electrolyte additive that effectively improves the cycle stability of the lithium metal anode and inhibits dendrite *** focus of this paper is on inhibiting the formation and growth of lithium *** coulombic efficiency of a Li|Cu battery with this acidified cellulose ester additive remains stable at 99%after 500 cycles under a current density of 1 mA/cm^*** batteries also remain stable after 500 cycles(1000 h)under a current density of 1 mA/cm^*** superior properties can be ascribed to the induced nucleation and the uniform distribution of lithium ion *** study uncovers an approach for effectively enabling stable cycling of dendrite-free lithium metal anodes.

关键词： Lithium metal batteries Acidified cellulose ester Lithium dendrite Electrolyte additive Stable cycling

Impact of effective stress on permeability for carbonate fractured-vuggy rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 942-960页

作者： Ke Sun Huiqing liu Juliana Y.Leung Jing Wang Yabin Feng renjie liu Zhijiang Kang Yun Zhang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China School of Mining&Petroleum Engineering University of AlbertaEdmontonT6G 1H9Canada SINOPEC Petroleum Exploration and Production Research Institute Beijing100083China

To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(*** stress conditions)for the fractured core models and the vuggy core models have similar change *** ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy *** each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and ***,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was *** is proved theoretically that the ESCP of CFVR generally varies between 0 and ***,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial *** concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the *** general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs.

关键词： Effective stress Permeability Carbonate fractured-vuggy rocks Structure characteristics Stress sensitivity

Porous Si/C composite as anode materials for high-performance rechargeable lithium-ion battery

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Chinese Chemical Letters 2017年第12期28卷 2281-2284页

作者： Bingbing Deng Lian Shen Yangai liu Tao Yang Manshu Zhang renjie liu Zhaohui Huang Minghao Fang Xiaowen Wu Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences College of Materials and Environmental Engineering Hangzhou Dianzi University

A novel porous silicon was synthesized through a magnesiothermic reduction method of molecular sieve for the first time, Si/C composite was synthesized by using pitch as carbon source. The porous Si/C composite shows a high initial specific capacity of 2018.5 mAh/g with current density of 0.1 A/g. When the current density increases to 2 A/g, it still exhibits high average specific capacity of 640.3 mAh/g. The porous structure can remit the Si particle pulverization during the lithiation]delithiation process. This article can provide a reference for the research of the porous Si anode for the high performance rechargeable lithium-ion battery.

关键词： Magnesiothermic reductionPorous SiLithium-ion battery Anode materials Carbon coating

The Chinese Language- a New Craze

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China Today 2005年第12期54卷 58-61页

作者： liu renjie

MARIE is a tour guide from France＇s Coted＇Azure. She didn＇t waste a minute of her 20-day tour of China. In addition to the usual sight-seeing and eating out in restaurants, she and her companions also attended an intensive Chinese training course. Marie wants to be a Chinese tour guide in her native land. She reckons that as France attracts more and more Chinese students, knowing the language will get her a better job.

关键词：中国汉语对外汉语教学文化交流