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Chinese Journal of Polymer Science 2024年第7期42卷 916-925,I0006页

作者： Bin zhang zheng-Li Dou yong-zheng zhang Qiang Fu Kai Wu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal *** role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully *** study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based *** findings reveal that the variations of SCAs modify both interface binding energy and transition layer *** interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line *** the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and ***,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.

关键词： Thermal interface material Surface modification Thermal conductivity Thixotropy Interface thermal resistance

The Frattini Subalgebra of Restricted Lie Superalgebras

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1343-1356页

作者： Liang Yun CHEN Dao Ji MENG yong zheng zhang Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China Department of Mathematics Northeast Normal University Changchun 130024 P. R. China Department of Mathematics Nankai University Tianjin 300071 P. R. China

In the present paper, we study the Frattini subalgebra of a restricted Lie superalgebra （L, [p]）. We show first that if L = A1 ＋ A2 ＋… ＋An, then Фp（L） = Фp（A1）＋Фp（A2）＋…＋Фp（An）, where each Ai is a p-ideal of L. We then obtain two results： F（L） = Ф（L） = J（L） = L if and only if L is nilpotent; Fp（L） and F（L） are nilpotent ideals of L if L is solvable. In addition, necessary and sufficient conditions are found for Фp-free restricted Lie superalgebras. Finally, we discuss the relationships of E-p-restricted Lie superalgebras and E-restricted Lie superalgebras.

关键词： restricted Lie superalgebras E-p-restricted Lie superalgebras Frattini p-subalgebra Фp- free p-elementary

Using the Phosphomannose Isomerase (PMI) Gene from Saccharomyces cerevisiae for Selection in Rice Transformation

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Journal of Integrative Agriculture 2012年第9期11卷 1391-1398页

作者： WANG Tao LIU Liang-yu TANG yong-yan zhang Xiao-bo zhang Mei-dong zheng yong-lian zhang Fang-dong National Key Laboratory of Crop Genetic Improvement Ministry of Science and Technology/Huazhong Agricultural University Wuhan 430070P. R. China

The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacterium-mediated transformation. The concentration of mannose during the selection was stepwise increased, 5 g L-1 mannose combined with 15 g L-1 sucrose and 500 mg L-1 cefotaxime was used in the initial selection stage, then the concentration of mannose was increased to 11 g L-1, the highest transformation rate was 20.0%. The integration of PMI gene was confirmed by PCR, and the result of RT-PCR assay proved that the intron of PMI gene can be excised correctly during RNA splicing. 13- Glucuronidase （GUS） activity analysis confirmed the expression of GUS gene. All those means the PMI gene from yeast can be used as a selectable marker in rice transformation.

关键词： phosphomannose isomerase selectable marker Saccharomyces cerevisiae transformation rice

Community structure and regeneration types of Betula dahurica forest in Badaling forest center of Beijing

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Forestry Studies in China 2007年第2期9卷 152-156页

作者： zhang yong zheng Zhi-hua zhang Zhi-xiang College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 P. R. China

Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the ＂1238＂ mountain of Badaling in Beijing, China. The results show that： 1） There are 33 plant species in the B. dahurica community, including 18 woody plant species. The B. dahurica forest is a monodominant community with 75.9% dominance. 2） Based on diameter at breast height （DBH） size class distribution, the population structure of B. dahurica and Acer mono--two heliophyllous and pioneer tree species-is cascade-type, with both in an increasing stage. The population structure of Ella mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4. 3） The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency ofF. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.

关键词： Betula dahurica forest community structure population structure regeneration type

Efficient polysulfides conversion on Mo_(2)CT_(x)MXene for highperformance lithium–sulfur batteries

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Rare Metals 2022年第1期41卷 311-318页

作者： Qi Zhu Hong-Fei Xu Kai Shen yong-zheng zhang Bin Li Shu-Bin Yang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The severe shuttle effect and sluggish redox kinetics of polysulfides hinder the application of lithium–sulfur ***,delaminated Mo_(2)CT_(x) MXene nanosheets are derived by chemical etching approach and further applied as a sulfur host for sulfur spheres(S@Mo_(2)CT_(x)).In the MXene encapsulated architecture,the external MXene nanosheets not only immobilize the soluble polysulfides by strong chemical adsorption but also efficiently catalyze the liquid–liquid conversion and liquid–solid nucleation process of lithium *** addition,the S@Mo_(2)CT_(x) electrode delivered fast charge and lithium-ion transport due to the superior electric conductivity and low lithiumion diffusion energy barrier of MXene *** a result,the S@Mo_(2)CT_(x) electrode exhibits a high reversible capacity of 918 mAh·g^(-1) at 1.0C with good cycling stability and a high areal capacity of 7.0 mAh·cm^(-2) with sulfur loading of 7.4 mg·cm^(-2) under a lean electrolyte condition.

关键词： lithium MXene electrode

Construction of metal-organic frameworks with unsaturated Cu sites for efficient and fast reduction of nitroaromatics:A combined experimental and theoretical study

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Chinese Chemical Letters 2024年第8期35卷 514-519页

作者： Longlong Geng Huiling Liu Wenfeng Zhou yong-zheng zhang Hongliang Huang Da-Shuai zhang Hui Hu Chao Lv Xiuling zhang Suijun Liu Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou 253023China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China State Key Laboratory of Separation Membranes and Membrane Processes School of Chemical Engineering and TechnologyTiangong UniversityTianjin 300387China School of Chemistry and Chemical Engineering Jiangxi Provincial Key Laboratory of Functional Molecular Materials ChemistryJiangxi University of Science and TechnologyGanzhou 341000China

Metal-organic frameworks(MOFs)functionalized with open metal sites(OMSs)have received widespread attention in various applications due to their fascinating electronic properties and unique interactions with guest ***,rational tailoring of the coordination environment of metal nodes dur-ing the synthesis of MOFs remains a great challenge due to their tendency of saturated coordination with ***,we reported the construction of three new MOFs featuring unsaturated Cu(Ⅱ)sites,namely[Cu(HCOO)(pzta)]_(n)(HL-1),{[Cu(PTA)0.5(pzta)(H_(2)O)]·2H_(2)O}_(n)(HL-2)and[Cu(NA)0.5(pzta)]_(n)(HL-3)(Hpzta=3-pyrazinyl-1,2,4-triazole;PTA=terephthalic acid;NA=1,4-naphthalene dicarboxylic acid),based on the mixed-linker strategy via specific selection of versatile Hpzta ligand and carboxylate ***-markably,the obtained MOFs exhibited excellent activity and good recyclability for the catalytic reduction of nitroaromatics under mild conditions(25℃and 1 atm).In particular,the complete conversion of 4-nitrophenol(4-NP)took only 30 s on HL-2,reaching a record-high TOF value compared with previously reported metal *** combined experimental and theoretical studies on HL-2 revealed that the open Cu site with positive-charged nature could improve the adsorption and subsequent electron trans-port between the substrates,and was responsible for the outstanding *** work shined lights on the further enhancement of performance for MOFs through rational OMSs construction.

关键词： Metal-organic frameworks Open metal sites Catalysis Copper node 4-Nitrophenol

Harnessing the unique features of MXenes for sulfur cathodes

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Tungsten 2020年第2期2卷 162-175页

作者： Zhen‑Jiang Cao yong‑zheng zhang Yang‑Lan‑Sen Cui Bin Li Shu‑Bin Yang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Lithium-sulfur(Li-S)battery,as an emerging rechargeable energy-storage system,sparks intensive research enthusiasm owing to its high theoretical energy ***,the sulfur cathode undergoes the low coulombic efficiency,poor rate and cycling performance,caused by the polysulfides shuttle,low conductivity and sluggish redox *** address the above issues,various hybrid sulfur cathodes are developed based on two-dimensional(2D)***,2D transition metal carbides and nitrides(MXenes)are receiving intensive interest as matrix materials for sulfur cathodes owing to their favorable properties,such as superior electrical conductivity,abundant active sites and adjustable surface functional *** this review,we mainly summarize the development of novel hybrid sulfur cathodes by taking advantage of unique properties of *** different roles MXenes played in sulfur cathodes,including facilitating the electron transfer,tuning the adsorption of polysulfides and catalyzing polysulfides conversion,are well ***,we propose the future strategies on the rational design of MXene-based sulfur cathodes with high performances.

关键词： MXenes Sulfur cathodes Shuttle effect Chemisorption Electrocatalysis

Z-Graded Lie Superalgebras with Depth One over Fields of Prime Characteristic

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Acta Mathematica Sinica,English Series 2002年第4期18卷 687-700页

作者： yong zheng zhang Department of Mathematics. Northeast Normal University. Changchun 130024. P. R. China Department of Mathematics Northeast Normal University Changchun 130024 P. R. China

Let F be a field of characteristic p>3, and L=_(i≥-1) L_i the finite-dimensional transitive Z-graded simple Lie superalgebra over F. In this paper L is determined if the Z-graded Lie superalgebra L_(-1) L_O is isomo... 详细信息

关键词： Lie superalgebra Exterior algebra Field of prime characteristic

A stable Zn-MOF with anthracene-based linker for Cr(Ⅵ)photocatalytic reduction under sunlight irradiation

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Chinese Chemical Letters 2024年第12期35卷 344-350页

作者： Yan-Kai zhang yong-zheng zhang Chun-Xiao Jia Fang Wang Xiuling zhang Yuhang Wu Zhongmin Liu Hui Hu Da-Shuai zhang Longlong Geng Jing Xu Hongliang Huang Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou 253023China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China State Key Laboratory of Separation Membranes and Membrane Processes School of Chemical Engineering and TechnologyTiangong UniversityTianjin 300387China

The highly desired goal is to employ visible light for the photocatalytic reduction of toxic Cr(Ⅵ)to environmentally friendly Cr(Ⅲ).Metal-organic frameworks(MOFs)are considered one of the most promising materials for the photoreduction of Cr(Ⅵ).Nevertheless,developing MOFs with high stability and activity is still ***,we report a stable Zn-based MOF(named DZU-64)with an anthracene functionalized ligand,and its reduction of Cr(Ⅵ)under sunlight irradiation was ***-64 exhibits excellent chemical stability in pH range of 2-14 aqueous solution,and remarkable thermal stability to570℃.For the photoreduction of Cr(Ⅵ)under visible light irradiation,DZU-64 gives a record rate constant of 0.467 min^(-1)and a high Cr(Ⅵ)reduction rate of 6.68 mg Cr_((Ⅵ))g^(-1)_(cata)min^(-1)at p H ***,under real solar light,DZU-64 can also efficiently reduce Cr(Ⅵ)to Cr(Ⅲ)while retaining its catalytic activity throughout 5 cycles without any notable decline,further demonstrating its great application *** combining the photovoltaic performance tests and electron spin resonance test,the possible photoreduction of Cr(Ⅵ)mechanism in DZU-64 was analyzed.

关键词： Metal-organic frameworks Anthracene-based ligand Cr(Ⅵ)reduction Photocatalysis Stability

Modular Lie Superalgebras of H-type

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Acta Mathematicae Applicatae Sinica 2004年第4期 683-694页

作者： yong zheng zhang Department of Mathematics,Harbin Normal University,Harbin 150080,P.R.China

In this article the Z-graded transitive modular Lie superalgebra -1 Li,whose repre-sentation of Lin Lis isomorphic to the natural representation of osp(L),is determined.

关键词： Modular Lie superalgebra Divided power algebra Exterior algebra Flag