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Quasiprobability Distribution of Squeezed Thermal Spin States in Ferromagnet

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Communications in Theoretical Physics 2008年第3期49卷 777-782页

作者： XU qin-Feng CHENG ze Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We study squeezed properties of magnon squeezed thermal spin states by using the distribution of Q function in the ferromagnet. It is found that the distribution of Q function strongly depends on the temperature T and coupling parameter γ. Below the transition temperature Tc, the distribution Q function in the squeezed thermal spin state presents a richer structure than in the normal state. Non-classical effects have been observed. In the transition from the normal to the squeezed thermal spin state, the phase symmetry of the magnon system is spontaneously broken.

关键词： squeezed thermal spin state ferromagnon quasiprobability distribution function

The preparation of whole sp-C composed alkyne rich carbon materials

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Nano Research 2023年第11期16卷 12618-12625页

作者： Deyi Zhang ze Yang Wenjing liu Xingru Yan qin liu Xiaodong li Changshui Huang Yuliang li Beijing National Laboratory for Molecular Sciences Organic Solids LaboratoryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China

For the high content of sp-hybridized carbon atoms,carbyne based materials can express superior conductivity and ultra-high theoretical capacity,which are key factors of high-performance ***,the poor stability of synthetic intermediates and unwanted side reactions lead to huge challenge to synthesis carbyne alternating carbon–carbon triple and single ***,we rationally designed a smart“Greedy Snake”strategy to synthesize the alkyne rich carbon materials named Si capped alkyne rich carbon(Si-Alkyne-C)which comprised of sp-hybridized carbon *** as-prepared Si-Alkyne-C generated on the copper surface through a carbon–carbon coupling,in which Si can effectively protect the intermediates generated by the *** C–Si bond can constantly generate copper-alkyne intermediates to couple with other terminal alkynes to continuously elongate like"Greedy Snake",forming a long alkyne chain *** as-prepared Si-Alkyne-C can be applied as anode electrodes,exhibited very high reversible capacity of up to 2776 mAh/g at a current density of 50 mA/g and an average capacity around 1202 mAh/g at a high current density of 5000 mA/g for 5000 cycles,which are the best results among the reported carbon materials and better than many other anode *** results not only provide a facile strategy to prepare carbyne based materials,but also open a broad avenue for the preparation of high-capacity anode materials.

关键词： alkyne rich carbon materials sp-hybridized carbon anode material energy storage lithium storage

Asymptotic stability of solitons to 1D nonlinear Schrodinger equations in subcritical case

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Frontiers of Mathematics in China 2020年第5期15卷 923-957页

作者： ze li School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

We prove the asymptotic stability of solitary waves to 1D nonlinear Schrodinger equations in the subcritical case with symmetry and spectrum *** of the main ideas is to use the vector fields method developed by ***,***,and ***[*** ***.,2013,6:957-980]to overcome the weak decay with respect to t of the linearized equation caused by the one dimension setting and the weak nonlinearity caused by the subcritical growth of the nonlinearity ***,we apply the polynomial growth of the high Sobolev norms of solutions to 1D Schrodinger equations obtained by ***[Duke Math.J.,1997,86(1):109-142]to control the high moments of the solutions emerging from the vector fields method.

关键词： Nonlinear Schrodinger equation(NLS) solitons weak nonlinearity asymptotic stability

Theoretical design of new bridge-ring insensitive high energy compounds by selected normal Diels-Alder reactions between NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes

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Defence Technology（防务技术） 2021年第5期17卷 1731-1739页

作者： Qiong Wu qin-nan Hu Ming-quan li ze-wu Zhang Wei-hua Zhu Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology1 Hongjing RoadNanjing211167China Institute for Computation in Molecular and Materials Science and Department of Chemistry Nanjing University of Science and TechnologyNanjing210094China

In this work,NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes were designed and used as dienes and dienophiles,respectively,in order to develop new bridge-ring insensitive high energy compounds through the Diels-Alder reaction between *** reaction type,reaction feasibility and performance of reaction products were investigated in detail *** results showed that dienes most possibly react with dienophiles through the HOMO-diene controlled normal Diels-Alder reaction at relatively low energy *** could react with the designed dienes much more easily than other dienophiles,and was employed to further design 29 new bridge-ring energetic *** to high heat of formation,density and oxygen balance,all designed bridge-ring energetic compounds have outstanding detonation performance,16 of them have higher energy than HMX(1,3,5,7-tetranitro-1,3,5,7-tetrazocine)and 2 others even possess comparative energy with the representative of high energy compounds CL-20(2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane).The predicted average h50 value of these bridge-ring energetic compounds is 83 cm,showing their low impact *** NH2 groups could obviously impel the proceeding of Diels-Alder reactions,but would slightly decrease the energy and sensitivity *** all,the new designed bridge-ring compounds have both high energy and low sensitivity,and may be produced through Diels-Alder reactions at relatively low energy *** paper may be helpful for the theoretical design and experiment synthesis of new advanced insensitive high energy compounds.

关键词： Diels-Alder Energetic compounds Oxazole High energy Insensitive

基于空中计算CoMAC架构的不同计算场景叠加符号判决算法

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 61-70页

作者：秦晓卫周子涵陈力中国科学技术大学信息科学技术学院安徽合肥230027

本文研究不同场景下基于空中计算的多址信道计算(CoMAC)架构的覆盖符号决策算法。首先,从理论上分析了XOR、ADD、MOD三种场景中加性高斯白噪声(AWGN)多址接入信道下叠加符号的概率密度分布,提出了一种基于先验概率的最优门限判决策略。... 详细信息

本文研究不同场景下基于空中计算的多址信道计算(CoMAC)架构的覆盖符号决策算法。首先,从理论上分析了XOR、ADD、MOD三种场景中加性高斯白噪声(AWGN)多址接入信道下叠加符号的概率密度分布,提出了一种基于先验概率的最优门限判决策略。其次,推导了系统最优门限及对应误码率的理论表达式。最后,通过仿真验证了不同信噪比、传感器节点个数及先验概率对于该门限判决方案的鲁棒性和可靠性的影响。与通信计算相分离的传统方案相比,空中计算判决方案具有更好的检测性能,为多址接入信道下的信号识别提供了新的参考方案。

关键词：空中计算多址接入信道最优门限判决检测性能

Microstructure,fracture behavior,in vitro corrosion resistance,and cytotoxicity of Zn-Mg/Mg-Zn-HAp laminated composites produced by spark plasma sintering

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Rare Metals 2021年第4期40卷 939-951页

作者： Ya-Kai Zhang ze-qin Cui Dian-qing Gong Wen-Xian Wang Wei-li Cheng School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of TechnologyTaiyuan 030024China Shanxi Province Boiler and Pressure Vessel Supervision and Inspection Institute Taiyuan 030024China

Ideal biodegradable materials exhibit suitable degradation rates and sufficient mechanical properties for their specific *** these parameters in mind,Zn-Mg/Mg-Zn-hydroxyapatite(HAp) laminated composites were designed and fabricated by spark plasma *** paper describes the structure,mechanical properties,in vitro corrosion resistance,and cytotoxicity of the Zn-Mg/Mg-Zn-HAp laminated *** compressive strength and elastic moduli of the laminated composites matched that of cortical bone and could effectively reduce the stress shielding effect as an implant with good biomechanical *** of the fracture path and morphology after fracture toughness tests indicated that the Zn-Mg/Mg-Zn-HAp laminated composites exhibited significant capacity to prevent crack propagation,improving the fracture *** vitro degradation experiments showed that the design of the laminated structure can provide a gradient degradation rate for the ***,the laminated composites exhibited excellent biocompatibility and are promising candidates for orthopedic implants.

关键词： Laminated composites Zn-Mg composites Spark plasma sintering Microstructure Fracture behavior In vitro degradation Cytotoxicity

HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

Photoenzymatic RAFT Emulsion Polymerization with Oxygen Tolerance

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Chinese Journal of Polymer Science 2021年第9期39卷 1138-1145页

作者： Ruo-Yu li ze-Sheng An State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China Institute of Nanochemistry and Nanobiology College of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China

Photoenzymatic reversible addition-fragmenatation chain transfer(RAFT)emulsion polymerization,surfactant-free or ab initio,of various monomers is reported with oxygen *** surfactant-free emulsion polymerizatoin,poly(N,N-dimethylacrylamide)s were used as stabilizer blocks for emulsion polymerization of methyl acrylate,n-butyl acrylate and styrene,producing well-defined amphiphilic block copolymers,including those with an ultrahigh molecular weight,at quantitative *** controlled character of surfactant-free emulsion polymerization was confirmed by kinetic studies,chain extension studies and GPC *** control was demonstrated by light ON/OFF *** ab initio emulsion polymerization of methyl acrylate and methyl methacrylate,low-dispersity hydrophobic polymers were synthesized with predictable molecular *** study extends the monomer scope suitable for photoenzymatic RAFT polymerization from hydrophilic to hydrophobic monomers and demonstrates that oxygen-toleranee can be equally achieved for emulsion polymerization with excellent RAFT control.

关键词： Controlled radical polymerization RAFT Emulsion polymerization Oxygen toleranee Photoenzymatic polymerization

Cubic Diophantine Inequalities

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Acta Mathematica Sinica,English Series 2001年第1期17卷 153-160页

作者： Hong ze li Department of Mathematics Shandong University

Let λ1, λ2,...,λ7 be real numbers satisfying λi≥1. In this paper, we prove there are integers x1,...,x7 such that the inequalities |λ1x13+λ2x23+...+λ7x73|i|xi]3 （λ1λ2…λ7）89814) hold simultaneously.

关键词： Diophantine inequality Cubic equation Non-trivial solution