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Effect of Nb^(5+)and Cu^(2+)codoping on thermal properties of Gd_(2)Zr_(2)O_(7)ceramic

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Journal of Rare Earths 2021年第2期39卷 180-185页

作者： Tao Jiang min xie Lili Guan Xuanli Wang Xiwen Song School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China

In this work,Nb^(5+)and Cu^(2+)were selected to partially substitute Zr4+in Gd_(2)Zr_(2)O_(7)for studying the phase structure,microscopic morphology and thermal ***_(2)(Zr_(1-3 x/2)Nb_(x)CU_(x/2))_(2)O_(7)(x=0,0.05,0.1,0.15,0.2,0.25)ceramic materials were synthesized by high-temperature solid-state reaction *** results show that the Gd_(2)(Zr_(1-3 x/2)Nb_(x)Cu_(x)/2)_(2)O_(7)ceramics present cubic pyrochlore structure with clear grain boundaries and dense cell *** the thermal expansion coefficient of Gd_(2)(Zr_(1-3 x/2)Nb_(x)Cu_(x/2))_(2)O_(7)ceramics gradually decreases because of the incorporation of Nb^(5+)and Cu^(2+)into Zr-site in Gd_(2)Zr_(2)O_(7).Meanwhile,its thermal conductivity decreases firstly and then increases with the doping of Nb^(5+)and Cu^(2+),which reaches the lowest value for the composition of Gd_(2)(Zr_(0.85)Nb_(0.1)Cu_(0.05))_(2)O_(7).

关键词： Gd_(2)Zr_(2)O_(7) Co-doping Pyrochlore structure Thermal properties Rare earths

Research of cycloaliphatic epoxy resin and silicone rubber composite insulator interface based on four-electrode system and temperature rise model

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High Voltage 2023年第3期8卷 560-569页

作者： Yunsong Wang Yuhao Liu Hongwei Mei min xie Liming Wang Shenzhen International Graduate School(SIGS) Tsinghua UniversityShenzhenChina Research Institute of Tsinghua Pearl River DeltaGuangzhouChina

Interface degradation between mandrel and sheath can cause a decrease in insulation performance and mechanical strength of composite *** this study,the interface ageing properties of cycloaliphatic epoxy resin and silicone rubber composite insulator were compared.A water diffusion test was adopted to simulate the composite insulator ageing in a hot and humid environment.A four-electrode system was built to detect leakage current at different locations(mandrel,sheath and interface),which is an important basis for evaluating insulator *** ageing degree of insulator could be quantitatively characterised by leakage current *** was found that the infiltrated moisture had a great effect on insulation *** on the water absorption test result,the interface performance of two insulators was mainly influenced by their sheath sealing *** an auxiliary evaluation method,temperature rise during the test was recorded using an infrared *** experiment results showed that interface degradation was the main factor for the insulation performance decrease of silicone rubber composite ***,insulation level reduction of the cycloaliphatic epoxy resin was caused by the wet *** addition,a model for temperature rise of cycloaliphatic epoxy resin insulators was proposed based on good correspondence between sheath material and *** model incorporated multiple processes such as ageing and heating of insulators,and it can predict the early temperature rise well.

关键词： insulator composite interface

Hierarchical CoNi-LDH nanosheet array with hydrogen vacancy for high-performance aqueous battery cathode

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Journal of Energy Chemistry 2022年第6期31卷 9-15,I0001页

作者： Wang Qiao Bowen Jin Wenfu xie mingfei Shao min Wei State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Aqueous rechargeable multiple metal-ion storage battery (ARSB) has a large potential in energy storage devices due to their safe usage, low cost and high rate capability. Nevertheless, the performance of practical ARSB is largely restricted by low capacity and limited cathode materials. Herein, we demonstrate an efficient cathode material based on Co Ni-layered double hydroxide (LDH) nanosheets arrays with abundant hydrogen vacancy induced by electrochemical activation process for high performance of cations storage. Consequently, the electrochemical activated Co Ni-LDH (ECA-Co Ni-LDH) nanosheets arrays exhibit high metal ion (Li^(+), Na^(+), Zn^(2+), Mg^(2+) and Ca^(2+)) storage capacities, which is 9 times and 3 times higher that of unactivated Co Ni-LDH arrays and ECA-Co Ni-LDH without hierarchical structure, ***, the ECA-Co Fe-LDH also shows the possibility for practical applications in actual *** coupling with a Fe_(2)O_(3)/C anode, the assembled aqueous battery delivered a large energy density of 184.4 Wh kg^(-1)at power density of 4 Wh kg^(-1) in high voltage range of 0–2 V. To our best knowledge, such high energy density and large working window of our assembled aqueous battery is exceeded other LDH-based aqueous battery or supercapacitor, and the energy density almost comparable than that of commercial Li-ion batteries. Moreover, almost no measurable capacitance losses can be detected even after 10000 cycles. In addition, this work also provides a strategy to develop a high energy density cathode for multiple metal-ion storage batteries.

关键词： Layered double hydroxides Multiple ions intercalation Hierarchical structure Hydrogen vacancy Aqueous battery

On Study of Solutions of Kac-van Moerbeke Lattice and Self-dual Network Equations

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Communications in Theoretical Physics 2006年第1期45卷 36-40页

作者： xie Fu-Ding JI min GONG Ling Department of Computer Science Liaoning Normal University Dalian 116029 China Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science the Chinese Academy of Sciences Beijing 100080 China

The closed form of solutions of Kac-van Moerbeke lattice and self-dual network equations are considered by proposing transformations based on Riccati equation, using symbolic computation. In contrast to the numerical computation of travelling wave solutions for differential difference equations, our method obtains exact solutions which have physical relevance.

关键词： Kac-van Moerbeke lattice self-dual network equation Riccati equation closed form solution

Study on the geological conditions of metallogenesis of the Shazi large-scale anatase deposit in Qinglong County, Guizhou Province

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Chinese Journal Of Geochemistry 2014年第4期33卷 450-458页

作者： ZHANG min NIE Aiguo xie Fei ZHANG Zhuru Guizhou Institute of Technology Guizhou University

The Shazi large-scale anatase deposit in Qinglong County, Guizhou Province, has been discovered recently and now is under exploration. Investigations show that the orebodies mostly occur at the top of the karst unconformity of the Middle Permian Maokou Formation strata and at the bottom of the Emeishan basalt. And the following three prerequisites should be satisfied for the formation of the deposit: 1) there must be the material source of anatase; 2) there must be weekly alkaline media and low-tempeature and low-pressure conditions; 3) there was no high-temperature and high-pressure environment subsequently for the transformation of anatase into rutile. In the Emeishan basalt of western Guizhou, the element Ti mostly entered the silicon-oxygen tetrahedra of picrite in heterovalent isomorphism(Ti4++Al3+→Mg2++Si4+). When volcanic ejecta resultant from strong eruption of the Emeishan basalt magma fell into water, picrite was usually dissociated to chlorite. Thus, the element Ti4+ in the picrite could be released from the silicon-oxygen tetrahedraa of picrite into water, and conbined with oxygen in the water to form Ti O2. This paper has proved that this deposit, enriched in anatase, discovered recently at Shazi, Qinglong Country, Guizhou Province, is a residual-deluvial-type deposit. Its genesis can be explained as follows. Volcanic clastics formed at the early stage of strong eruption of the Emeishan basalt magma were chemically deposited to form anatase in the low-temperature, low-pressure and weekly alkaline waters in the karst depressions at the top of the Maokou Formation(limestone) strata. The anatase was then dissociated owing to weathering and leaching during the Quaternary and the anatase was further enriched to form the residual-deluvial-type anatase ore deposit.

关键词：矿床成矿锐钛矿贵州省晴隆县地质条件峨眉山玄武岩火山喷发物硅氧四面体

Structural insights into the assembly of human translesion polymerase complexes

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Protein & Cell 2012年第11期3卷 864-874页

作者： Wei xie Xuan Yang min Xu Tao Jiang National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of Sciences15 Datun RoadChaoyang DistrictBeijing 100101China The Graduate University of Chinese Academy of Sciences 19A Yuquan RoadShijingshan DistrictBeijing 100039China

In addition to DNA repair pathways,cells utilize translesion DNA synthesis(TLS)to bypass DNA lesions during *** TLS,Y-family DNA polymerase(Polη,Polκ,Polιand Rev1)inserts specific nucleotide opposite preferred DNA lesions,and then Polζ consisting of two subunits,Rev3 and Rev7,carries out primer ***,we report the complex structures of Rev3-Rev7-Rev1^(CTD) and Rev3-Rev7-Rev1^(CTD)-Polκ^(RIR).These two structures demonstrate that Rev1^(CTD) contains separate binding sites for Polκand *** BIAcore experiments provide additional support for the notion that the interaction between Rev3 and Rev7 increases the affinity of Rev7 and *** also verified through FRET experiment that Rev1,Rev3,Rev7 and Polκ form a stable quaternary complex in vivo,thereby suggesting an efficient switching mechanism where the“inserter”polymerase can be immediately replaced by an“extender”polymerase within the same quaternary complex.

关键词： translesion DNA synthesis Rev1 Polκ Polζ complex structure

Influence of Chemical Composition on Phase Transformation Temperature and Thermal Expansion Coefficient of Hot Work Die Steel

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Journal of Iron and Steel Research International 2008年第6期15卷 56-61页

作者： xie Hao-jie WU Xiao-chun min Yong-an School of Material Science and Engineering Shanghai University Shanghai 200072 China

On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1 , Ac3 , and Ms were measured by DIL805A quenching dilatometer. The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis, and three corresponding equations were obtained. These equations, in which the interactions of the elements were considered, showed more effectiveness than the traditional ones. In addition, the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests. The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed; the equations obtained were verified by using several kinds of steels. The predicted values were in accordance with the results of the experiments.

关键词： phase transformation temperature thermal expansion coefficient hot work die steel uniform design quadratic stepwise regression analysis

Dimensions of Weighted Besicovitch Sets

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Acta Mathematica Sinica,English Series 2010年第4期26卷 711-716页

作者： Yu Qiong xie Zhi Xiong WEN min YU Department of Mathematics School of Science Wuhan University of Technology Wuhan 430070 P. R. China Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 P. R. China School of Science Wuhan University of Science and Technology Wuhan 430081 P. R. China

We consider weighted Besicovitch sets which are defined in terms of the weighted frequency of digit 1 in the dyadic expansion of real numbers. Explicit formulas for their Hausdorff dimensions are given.

关键词： Hausdorff dimension weighted Besicovitch set

Microscopic insights into the catalytic mechanisms of monolayer MoS2 and its heterostructures in hydrogen evolution reaction

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Nano Research 2019年第9期12卷 2140-2149页

作者： min Hong Jianping Shi Yahuan Huan Qin xie Yanfeng Zhang Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China Center for Nanochemistry (CNC) Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Exploring high-efficient catalysts for hydrogen evolution reaction(HER)has become very urgeht for resolving the energy related ***,two-dimensional layered MoS2 and its heterostructures with graphene or other traditional photocatalysts have presented great potentials for electrocatalytic and photocatalytic HER ***-site investigations of the atomic-scale structures and local electronic properties of the catalytically active sites are the key points for understanding the internal mechanisms,which however are hard to be achievec from the practical ***,this review focuses on the recent progresses on the on-site scanning tunneling microscopy/spectroscopy investigations of the atomic structures and electronic properties of the ultrahigh-vacuum deposited and chemical vapor deposition(CVD)synthesized monolayer MoS2 and MoSz/graphene vertical stacks on the electrodes of Au(111)and Au *** correlations between the respective HER activities,edge types and edge electronic states are comparatively ***,this review also introduces thephotocatalytic HER applications of CVD-grown MoS2/WS2 and WS/MoS2 vertical stacks on Au foils,mainly considering of their type-ll *** and the novel interlayer charge transfer ***,future research directions are also proposed for in-depth understanding of the catalytic mechanism,as well as for exploring more efficient HER catalysts.

关键词： M0S2 seanning tunneling microscopy/spectroscopy hydrogen evolution reaction metallic edge states vertical stacks