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Chinese Chemical Letters 2020年第4期31卷 1014-1017页

作者： Xiuqiang Xie zhenjun wu Nan Zhang College of Materials Science and Engineering Hunan UniversityChangsha 410082China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China

Ti3C2Tx has been emerging as an attractive platform to prepare composite catalysts,and their assembly into integrated catalytic mate rials repre sents a key step forward toward practical *** r,the swelling behavior of Ti3C2Tx leads to significant structure change,which challenges the stability of Ti3C2Tx-based integrated functional materials for catalytic *** we report a facile synthesis of Pd/Ti3C2Tx■graphene hydrogels in which Pd/Ti3C2Tx are spatially encapsulated in the 3 D porous graphene *** porous interconnected structure not only affords efficient mass transfer and desirable functional accessibility to catalytic active sites,but also effectively buffers the swelling behavior of *** applied for catalytic hydrogenation of nitroaromatic compounds,the mechanically robust Pd/Ti3C2Tx■graphene hydrogels exhibit efficient activities,easy separability,and good *** work is expected to promote the application of Ti3C2Tx-based functional materials for practical applications involving interactions with salt solutions,such as supercapacitors,catalysis,and water purification.

关键词： Ti3C2Tx Hydrogels Robust structure Convenient recyclability Nitroaromatic compounds hydrogenation

Effect of non-solvent additives on the morphology,pore structure, and direct contact membrane distillation performance of PVDF-CTFE hydrophobic membranes

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Journal of Environmental Sciences 2016年第7期28卷 28-39页

作者： Libing Zheng zhenjun wu Yong Zhang Yuansong Wei Jun Wang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing Key Laboratory of Industrial Wastewater Treatment and Resource Recovery Research Center for Eco-Environmental SciencesChinese Academy of Sciences School of Chemical & the Environment Beijing Institute of Technology

Four common types of additives for polymer membrane preparation including organic macromolecule and micromolecule additives, inorganic salts and acids, and the strong non-solvent H2 O were used to prepare poly（vinylidene fluoride-co-chlorotrifluoroethylene）（PVDF-CTFE） hydrophobic flat-sheet membranes. Membrane properties including morphology, porosity, hydrophobicity, pore size and pore distribution were investigated, and the permeability was evaluated via direct contact membrane distillation（DCMD） of 3.5 g/L Na Cl solution in a DCMD configuration. Both inorganic and organic micromolecule additives were found to slightly influence membrane hydrophobicity. Polyethylene glycol（PEG）,organic acids, Li Cl, Mg Cl2, and Li Cl/H2 O mixtures were proved to be effective additives to PVDF-CTFE membranes due to their pore-controlling effects and the capacity to improve the properties and performance of the resultant membranes. The occurrence of a pre-gelation process showed that when organic and inorganic micromolecules were added to PVDF-CTFE solution, the resultant membranes presented a high interconnectivity structure. The membrane prepared with dibutyl phthalate（DBP） showed a nonporous surface and symmetrical cross-section. When H2 O and Li Cl/H2 O mixtures were also used as additives, they were beneficial for solid–liquid demixing, especially when Li Cl/H2 O mixed additives were used. The membrane prepared with 5% Li Cl ＋ 2% H2 O achieved a flux of24.53 kg/（m2·hr） with 99.98% salt rejection. This study is expected to offer a reference not only for PVDF-CTFE membrane preparation but also for other polymer membranes.

关键词： PVDF-CTFE Additives Phase inversion Membrane distillation Pre-gelation

LDHs derived nanoparticle-stacked metal nitride as interlayer for long-life lithium sulfur batteries

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Science Bulletin 2018年第3期63卷 169-175页

作者： Zhen Li Zhaoling Ma Yanyong Wang Ru Chen zhenjun wu Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and Devices College of Chemistry and Chemical Engineering Hunan University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province Shenzhen University

Shuttle effect is one of the most serious disadvantages in lithium-sulfur battery which results in poor cycle performance and hinders the commercialization of Li-S *** reduce the dissolution of polysulfides into the electrolyte and prolong the cycling stability,nanoparticle-stacked metal nitride derived from layered double hydroxides(LDHs)as an interlayer was inserted between sulfur cathode and separator to confine polysulfides by physical and chemical ***,the surface of metal nitride will form an oxide passivation *** passivation layer possesses hydrophilic metal-O group and provides a polar surface for strong binding with ***’s more,the nanoparticlesstacked structure could immerge and retain electrolyte well,which could enhance the ability of promoting the electron exchange *** sulfur electrode with nanoparticle-stacked metal nitride interlayer has an excellent cycle performance owing to the interactions between metal nitride and *** battery delivered an initial capacity of 764.6 m Ahg^(-1) and still possesses a capacity of 477.5 mAhg^(-1) with the retention of 62.4% after 800 cycles.

关键词： Nanoparticle-stacked structure Metal nitride InterlayerLithium polysulfides Li-S batteries

Room-Temperature Assembled MXene-Based Aerogels for High Mass-Loading Sodium-Ion Storage

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Nano-Micro Letters 2022年第2期14卷 282-295页

作者： Fei Song Jian Hu Guohao Li Jie Wang Shuijiao Chen Xiuqiang Xie zhenjun wu Nan Zhang College of Materials Science and Engineering Hunan UniversityChangsha 410082People’s Republic of China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082People’s Republic of China

Low-temperature assembly of MXene nanosheets into three-dimensional(3D) robust aerogels addresses the crucial stability concern of the nano-building blocks during the fabrication process,which is of key importance for transforming the fascinating properties at the nanoscale into the macroscopic scale for practical ***,suitable cross-linking agents(amino-propyltriethoxysilane,Mn^(2+),Fe^(2+),Zn^(2+),and Co^(2+)) as interfacial mediators to engineer the interlayer interactions are reported to realize the graphene oxide(GO)-assisted assembly of Ti_(3)C_(2)T_(x) MXene aerogel at room *** elaborate aerogel construction not only suppresses the oxidation degradation of Ti_(3)C_(2)T_(x) but also generates porous aerogels with a high Ti_(3)C_(2)T_(x) content(87 wt%) and robustness,thereby guaranteeing the functional accessibility of Ti_(3)C_(2)T_(x) nanosheets and operational reliability as integrated functional *** combination with a further sulfur modification,the Ti_(3)C_(2)T_(x) aerogel electrode shows promising electrochemical performances as the freestanding anode for sodium-ion *** at an ultrahigh loading mass of 12.3 mg cm^(-2),a pronounced areal capacity of 1.26 mAh cm^(-2) at a current density of 0.1 A g^(-1) has been achieved,which is of practical *** work conceptually suggests a new way to exert the utmost surface functionalities of MXenes in 3D monolithic form and can be an inspiring scaffold to promote the application of MXenes in different areas.

关键词： MXenes Aerogel Room-temperature assembly Interfacial engineering Sodium-ion storage

Problems and Countermeasures of International Trade Financing of Small and Medium-Sized Enterprises in China

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Proceedings of Business and Economic Studies 2021年第4期4卷 172-177页

作者： zhenjun wu Fuzhou Technology and Business University Fuzhou 350000China

Small and medium-sized enterprises are the foundation of China's national economy,and they are important forces to promote economic and social *** play an irreplaceable role in promoting scientific and technological progress,increasing social employment,expanding foreign trade,and other aspects in which they have become an important part of China's socialist market *** on the research background of international trade financing,this paper analyzes the problems existing in the international trade fmancing of small and medium-sized enterprises in China to put forward countermeasures and suggestions,hoping to help these small and medium-sized enterprises solve the financing problem so as to achieve a healthy development in the international trade market environment.

关键词： Small and medium-sized enterprises International trade Financing Countermeasures and suggestions

China Leading in Clean Energy Spending

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China Oil & Gas 2010年第2期17卷 18-20页

作者： wu zhenjun Zhongyuan Petroleum Exploration Bureau SINOPEC

China has taken the lead in investments in clean energy, spending nearly double what the US did in 2009, as it ramps up projects in both renewable and traditional energy. China’s investment and financing for clean

关键词：清洁能源中国能源投资可再生能源传统能源非营利性欧洲国家美元

Sliding-mode Observer-based Grid Voltage-observation Method with Frequency-fixed Dual SOGI and Cross-compensated Phase-locked Loop

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Chinese Journal of Electrical Engineering 2024年第3期10卷 37-49页

作者： Leilei Guo Qingyang Ye Nan Jin Zhenkun Liu zhenjun wu School of Electrical and Information Engineering Zhengzhou University of Light IndustryZhengzhou 450002China

Conventional sliding-mode observer(SMO)-based grid-voltage observation methods often require a low-pass filter(LPF)to remove high-frequency sliding-mode ***,a complicated phase-and amplitude-compensation method,which is highly sensitive to the DC-offset,is required.A frequency-adaptive dual second-order generalized integrator(SOGI)can be used to replace the LPF,eliminating the compensation link and the effects of the DC-offset;however,strong coupling is introduced between the front-end SOGI block and back-end phase-locked loop(PLL)block,thereby reducing the dynamic *** solve this problem,this study proposes an SMO-based grid-voltage observation method with a frequency-fixed dual SOGI and cross-compensated PLL that can eliminate the frequency coupling between the front-end SOGI block and back-end PLL blocks,thereby increasing its dynamic *** this study,the phase and amplitude are compensated simultaneously using the proposed cross-compensation method,achieving an accurate observation of the grid voltage under off-nominal *** analysis of the small-signal model theoretically verified that the proposed method has good dynamic ***,the superiority of the proposed method is verified through comparative experiments.

关键词： Sliding-mode observer(SMO) low-pass filter(LPF) second-order generalized integrator(SOGI) cross-compensation phase-locked loop(PLL) small-signal model

Loose coupling transformer efficiency analysis in contactless energy transmission system

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Loose coupling transformer efficiency analysis in contactles...

Study on Pinus elliottii Plantations in Pengchang Forest Farm of Jingmen City

2012 International Conference on Power Electronics Engineering and Computer Technology(PEECT 2012)

作者： wu zhenjun YanYan Jiang Yong Wang Xinjin College of Electric and Information Engineering Zhengzliou University of Light Industry

In the contactless energy transmission system,loose coupling transformer is one of the key factors in affecting energy transmission *** model of loose coupling transformer is established in this *** changing the structure of the magnetic core and winding,the main parameters which impact loose coupling transformer transmission efficiency have been *** to characteristics that transmission efficiency is low of the U（E） type core and different winding form,the flat E type core and plane winding is used to design loose coupling *** the simulation and comparison,the new loose coupling transformer structure can improve the system energy transfer efficiency greatly,and it can be used in the actual contactless energy transmission system.

关键词： Contactless energy transmission Loose coupling transformer Transmission efficiency

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Agricultural Biotechnology 2022年第5期11卷 76-79页

作者： Pengfei XU Maochang LIANG zhenjun wu Lidan FANG Yongjun FEI Die HU College of Horticulture and Landscape Architecture Yangtze UniversityJingzhou 434025China Pengchang Forest Farm Jingmen 448269China

[Objectives]This study was conducted to improve the ecological and economic benefits of Pinus elliottii plantations in Pengchang Forest Farm, Jingmen City. [Methods] P. elliottii plantations in Pengchang Forest Farm in Jingmen City were selected as the research object, and the appearance and quantitative characteristics of P. elliottii community were studied and analyzed by a sampling method. [Results] Phanerophytes were the most in the P. elliottii community, accounting for 50%. In the community, except P. elliottii, the importance values of native plants were higher. The order of species diversity of P. elliottii community in Pengchang Forest Farm was herb layer, tree layer and shrub layer. The stress resistance of the community was weak, and strong intraspecific competition existed in P. elliottii. It is recommended to thin P. elliottii trees with insufficient lighting, poor growth potential and severely damaged tree body, and interplant Phoebe zhennan after thinning the P. elliottii plantations, so as to create a coniferous and broad-leaved evergreen mixed forest. [Conclusions] This study provides scientific support for thinning, tending, and forest management of P. elliottii plantations.

关键词： Pinus elliottii Plantation Community science Tending thinning

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考虑地质成因的土坡可靠度分析

岩石力学与工程学报 2011年第9期30卷 1904-1911页

作者：吴振君葛修润王水林中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071

不同地质成因的边坡在土体参数统计变异性相同的情况下,由于空间变异性不同,其稳定状态并不一定相同,传统的边坡稳定性确定性分析和基于随机变量模型的边坡可靠度分析方法无法考虑坡体的特定地质成因。由地质成因估计土体参数的波动范围... 详细信息

不同地质成因的边坡在土体参数统计变异性相同的情况下,由于空间变异性不同,其稳定状态并不一定相同,传统的边坡稳定性确定性分析和基于随机变量模型的边坡可靠度分析方法无法考虑坡体的特定地质成因。由地质成因估计土体参数的波动范围,从而通过土体参数波动范围这一指标把地质成因纳入边坡稳定性分析框架,提出考虑地质成因的边坡可靠度分析方法,介绍具体的分析流程,采用一维随机场模拟和验算点法完成边坡可靠度分析。算例计算结果显示岩土参数空间变异性对边坡稳定性的影响很大,由地质成因估计土体参数的波动范围,为在边坡可靠度分析中合理考虑土体参数空间变异性提供一条现实的解决途径,值得在工程应用中推广。

关键词：边坡工程土坡可靠度概率分析地质成因空间变异性波动范围