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One-step in situ encapsulation of Ge nanoparticles into porous carbon network with enhanced electron/ion conductivity for lithium storage

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Rare Metals 2021年第9期40卷 2432-2439页

作者： Xue Qiao Xue-Biao Yang Na Zhang Xian-Ling Wang Ying-Ying Song yong-qing zhai Dan Li Hong-Qiang Wang College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

Germanium(Ge) is considered to be one of the most promising anode materials due to the high theoretical capacity and excellent rate capability. However, its further development is hindered by the poor cycling stability caused by the severe volume change. Herein, we demonstrate a one-step in situ synthesis of Ge nanoparticles embedded into porous carbon framework(PC@Ge) using a facile sacrificial template method via the introduction of poly(methyl methacrylate) and subsequent thermal treatment. This unique nanoarchitecture not only enhances lithium-ion diffusivity and electron conductivity, but also effectively buffers the huge volume expansion and protects the Ge nanoparticles from cracking and aggregation during the cycling. Consequently, the as-prepared PC@Ge electrode exhibits superior capacity retention of 75% and 87%over 1000 cycles at 1.0 and 2.0 A·g^(-1), respectively.

关键词： Lithium-ion batteries Germanium nanoparticle In situ synthesis Porous carbon frameworks Lithium-ion diffusivity

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对普通高校两种不同体育教学形式的调查分析

体育学刊 2002年第5期9卷 83-84页

作者：秦勇翟奕轩中原工学院体育部河南郑州475001

通过文献资料和问卷调查等方法 ,从学生对体育课的评价的角度分析了当前我院两种不同形式的体育教学对体育课教学效果产生的影响 ,为今后我国体育教学改革实践提供参考和借鉴。

关键词：普通高校体育教学形式

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槲皮素滴丸成型工艺的研究

槲皮素滴丸成型工艺的研究

Trinuclear gold-catalyzed site-selective alkylation of peptides

山东省药学会第一届学术年会

作者： yong De-qing, zhai Guang-xi, ZOU Man (The Pharmacy of Qilu Hospital, Shandong University, Jinan 250012, china)

目的槲皮素滴丸成型工艺。方法在单因素考察的基础上,以正交设计试验法研究槲皮素滴丸成型工艺。结果最佳成型工艺为槲皮素与基质比例1:3,药液温度(90±5) ℃,滴速每1min20滴,冷却剂温度为(15±2)℃。结论由最佳工艺制备所得槲皮素滴丸... 详细信息

目的槲皮素滴丸成型工艺。方法在单因素考察的基础上,以正交设计试验法研究槲皮素滴丸成型工艺。结果最佳成型工艺为槲皮素与基质比例1:3,药液温度(90±5) ℃,滴速每1min20滴,冷却剂温度为(15±2)℃。结论由最佳工艺制备所得槲皮素滴丸硬度、圆整度和重量差异均符合要求。

关键词：槲皮素滴丸正交设计

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Science China Chemistry 2025年第1期 249-256页

作者： qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Copper-Catalyzed Si-H Bond Insertion Polymerization for Synthesis of Optically Active Polyesters Containing Silicon

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Chinese Journal of Chemistry 2022年第1期40卷 21-27页

作者： Xiao-yong zhai Xiao-qing Wang Bo Wu yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The synthesis and characterization of chiral polymers with diverse structure remain a long-term challenging research ***,a copper-catalyzed enantioselective insertion of carbene into Si-H bond was applied to polycondensation,giving a new type of optically active degradable polyesters containing Si-C bond in the main *** polymerization features mild condition,broad substrate scope,excellent yields and *** diols could be obtained via reduction of optically active *** analysis indicated these chiral polyesters exhibit good thermal stability.

关键词： Polymerization Insertion Asymmetric catalysis Optically active polyesters Copper

Certain Cuntz Semigroup Properties of Certain Crossed Product C^*-algebras

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Acta Mathematica Sinica,English Series 2020年第3期36卷 337-362页

作者： qing zhai FAN Department of Mathematics Shanghai Maritime UniversityShanghai 201306P.R.C hina

We show that the following properties of the C^*-algebras in a class Ω are inherited by simple unital C-algebras in the class TAΩ:(1)(m,n)-decomposable,(2) weakly(m,n)-divisible,(3) weak Riesz *** an application,let A be an infinite dimensional simple unital C-algebra such that A has one of the above-listed *** that α:G→Aut(A) is an action of a finite group G on A which has the tracial Rokhlin *** the crossed product C^*-algebra C^*(G,A,α) also has the property under consideration.

关键词： C^*-algebras tracial approximation Cuntz semigroup

Partially biobased polymers:The synthesis of polysilylethers via dehydrocoupling catalyzed by an anionic iridium complex

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Chinese Chemical Letters 2020年第5期31卷 1197-1200页

作者： Xiao-yong zhai Xiao-qing Wang Yi-Xuan Ding yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Partially biobased polysilylethers(PSEs)are synthesized via dehydrocoupling polymerization catalyzed by an anionic iridium *** types(AB type or AA and BB type)of monomers are *** acid(LA)and succinic acid(SA)have been ranked within the top 10 chemicals derived from *** type monomers(diols)derived from LA and SA have been applied to the synthesis of *** polymerization reactions employ an air-stable anionic iridium complex bearing a functional bipyridonate ligand as *** to high yields of polymers with number-average molecular weights(Mn)up to 4.38×104 were obtained.A possible catalytic cycle via an Ir-H species is *** on the results of kinetic experiments,apparent activation energy of polymerization in the tempe rature range of 0-10℃is about 38.6 kJ/*** PSEs synthesized from AA and BB type monomers possess good thermal stability(T5=418℃to 437℃)and low glass-transition temperature(Tg=49.6℃).

关键词： Biodegradable polymers Polysilylethers Iridium catalysis Dehydrocoupling polymerization Levulinic acid

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高原环境爆炸冲击波传播规律及计算模型研究

火工品 2025年第1期 62-69页

作者：赵伟成翟红波李尚青毛伯永西安近代化学研究所陕西西安710065

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinn... 详细信息

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinney-Graham和Sachs修正公式的超压峰值和比冲量计算结果与试验结果,并采用Sachs修正中的温度修正项对Sadovskyi高原超压峰值公式进行了修正。研究结果表明:随着海拔的升高,冲击波的波阵面速度加快,到达时间提前,每升高1 km,冲击波超压峰值下降约2%~4%,比冲量下降约4%;对超压峰值进行修正时,3种修正公式均具有一定的准确性;对比冲量进行修正时,Kinney-Graham修正的比冲量值随比例距离增加呈线性降低,与试验结果吻合较差,庞春桥与Sachs的修正结果随比例距离增加呈指数降低;基于温度项修正的Sadovskyi高原冲击波超压峰值经验公式的平均误差减小了3.1%。该研究结果对于高海拔地区的弹药毁伤效能评估有参考意义。

关键词：爆炸试验高原环境冲击波传播特性计算模型

A Novel Vibration-Based Self-Adapting Method to Acquire Real-Time Following Distance for Virtually Coupled Trains

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 27-39页

作者： qinglai Zhang Jianmin Gao qing Wu qinglie He Libin Tie Wanming zhai Shengyang Zhu State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong University IEEE Centre for Railway Engineering Central Queensland University National Energy Railway Equipment Co. LTDNational Energy Group

Virtual coupling(VC) is an emerging technology for addressing the shortage of rail transportation capacity. As a crucial enabling technology, the VC-specific acquisition of train information, especially train following distance(TFD), is *** this paper, a novel method is proposed to acquire real-time TFD by analyzing the vibration response of the front and following trains, during which only onboard accelerometers and speedometers are required. In contrast to the traditional arts of train positioning, this method targets a relative position between two adjacent trains in VC operation, rather than the global positions of the trains. For this purpose, an adaptive system containing three strategies is designed to cope with possible adverse factors in train operation. A vehicle dynamics simulation of a heavy-haul railway is implemented for the evaluation of feasibility and performance. Furthermore, a validation is conducted using a set of data measured from in-service Chinese high-speed trains. The results indicate the method achieves satisfactory estimation accuracy using both simulated and actual data. It has favorable adaptability to various uncertainties possibly encountered in train operation. Additionally, the method is preliminarily proven to adapt to different locomotive types and even different rail transportation modes. In general, such a method with good performance, low-cost, and easy implementation is promising to apply.

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