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Entropy Conservation in the Transition of Schwarzschild-de Sitter Space to de Sitter Space through Tunneling

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Chinese Physics Letters 2012年第2期29卷 25-28页

作者： ZHANG Bao-Cheng cai qing-yu ZHAN Ming-Sheng State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 4300712 Center for Cold Atom Physics Chinese Academy of SciencesWuhan 430071

We revisit Parikh-Wilczek tunneling through the de Sitter horizon and obtain the tunneling rate in Schwarzschildde Sitter space,which is non-thermal and closely related to the change of *** discuss the thermodynamics of Schwarzschild-de Sitter space and show existence of correlation which can ensure conservation of the total entropy in the transition process of Schwarzschild-de Sitter space to de Sitter *** correlation and the conserved entropy provide a way to explain the entropy in empty de Sitter space.

关键词： horizon entropy Sitter

Continuous Cooling Transformation Behavior and Kinetic Models of Transformations for an Ultra-Low Carbon Bainitic Steel

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Journal of Iron and Steel Research International 2012年第12期19卷 73-78页

作者： ZHANG Zhi-min cai qing-wu yu Wei LIXiao-lin WANG Li-dong Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The aim was to investigate transformation behavior and transformation kinetics of an ultra-low carbon bai- nitic steel during continuous cooling. Continuous cooling transformation （CCT） curves of tested steel were measured by thermal dilatometer and metallographic structures at room temperature were observed by optical microscope. Then transformation kinetic equation of austenite to ferrite as well as austenite to bainite was established by analyzing the relationship of lnln]-l/（1--f）] and lnt in the kinetic equation on the basis of processed experimental data. Finally, the measured and calculated kinetic behaviors of the steel during continuous cooling were compared and growth pat- terns of transformed ferrite and bainite were analyzed. Results showed that calculated result was in reasonable agree- ment with the experimental data. It could be concluded that the growth modes of transformed ferrite and bainite were mainly one dimension as the Avrami exponents were between 1 and 2.

关键词： ultra low carbon bainitic steel continuous cooling transformation kinetics Avrami equation

The Conductivity of the Mixture of Polyacrylate Emulsion and Cationic Surfactants

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科技信息 2012年第3期 104-104,58页

作者： ZHANG Hai-chao cai yu-qing FANG Kuan-jun Laboratory of Fiber Materials and Modern Textiles The Growing Base for State Key Laboratory College of Chemical and Environmental Engineering Qingdao UniversityQingdao Shandong 266071 China

A polyacrylate emulsion containing sodium dodecyl sulfate(SDS) as a stabilizer was mixed with cetyltrimethyl ammonium chloride(CTAC) and a cationic surfactant containing an oxide ethylene chain(OEMD-20),*** results of experiment show that the mixtures of CTAC and PAE had higher conductivities than PAE;The mixtures of OEMD-20 had lower conductivities than PAE.

关键词：表面活性剂 SDS CTAC OEMD-20

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng cai Shengjun Miao yuan Li yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Conversion-type cathode materials for high energy density solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 409-425页

作者： yuhao Ma Shihong qing Hongyu Liu Chuntao Ma yuan yu Chuang yu Liping Wang School of Materials and Energy University of Electronic Science and Technology of China Zhejiang Provincial Key Laboratory of Fiber Materials and Manufacturing Technology Zhejiang Sci-Tech University State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology

Solid-state lithium batteries （SSLBs） are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy *** particular,SSLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and *** the great progress in research and development of SSLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing *** review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes （SSEs）,as well as state-of-the-art progress in various promising cathodes （e.g.,FeS2,CuS,FeF3,FeF2,and S） in ***,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical ***,the energy density exhibited by the S cathode stands out impressively,while sulfide SSEs and halide SSEs have demonstrated immense potential for coupling with conversion-type ***,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density SSLBs.

关键词： Sulfur compounds

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia yu Wang Chun Cheng Yang qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

SMA共聚物的合成及对超细颜料水性体系的分散作用

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高分子材料科学与工程 2005年第6期21卷 102-105,109页

作者：田安丽蔡玉青房宽峻张霞江南大学纺织服装学院江苏无锡214063 青岛大学化工学院山东青岛266071

采用溶液聚合法合成了苯乙烯-马来酸酐共聚物(SM A),用FT-IR1、3C-NM R、GPC等方法对所合成的共聚物进行了表征。结果表明,共聚物是M SM和SSM为主的无规聚合物,其分子量为27,599,多分散指数为2.35,具有较窄的分子量分布。将SM A用于超... 详细信息

采用溶液聚合法合成了苯乙烯-马来酸酐共聚物(SM A),用FT-IR1、3C-NM R、GPC等方法对所合成的共聚物进行了表征。结果表明,共聚物是M SM和SSM为主的无规聚合物,其分子量为27,599,多分散指数为2.35,具有较窄的分子量分布。将SM A用于超细颜料水性分散体系,发现体系的离心稳定性随SM A特性黏度的减小及马来酸酐含量的增加呈先增大后减小的趋势,加入第三单体甲基丙烯酸甲酯使分散体系的离心稳定性降低。当SM A的特性黏度为21 m l/g^23 m l/g,马来酸酐摩尔百分含量(FMA)为38.3%时,所制备的颜料分散液具有良好的分散性能,其黏度、粒径、表面张力均达到喷墨印花用墨水的要求。

关键词：聚苯乙烯-马来酸酐超细颜料合成分散性能

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冲击波活化热压烧结氮化硅粉末

国防科技大学学报 2000年第3期22卷 65-69页

作者：刘静宇蔡清裕张术华长沙大学理化系湖南长沙410003 国防科技大学理学院湖南长沙410073 国防科技大学航天与材料工程学院湖南长沙410073

对Si3 N4粉末实现了三种不同压力的冲击波预先处理 ,而后采用三种不同的热压烧结条件制得Si3 N4陶瓷。运用SEM ,TEM ,HRTEM和XRD等手段分析了粉末和陶瓷的结构特性 ,同时测试了材料的性能。结果表明 :冲击波压力没有导致Si3 N4粉末的相... 详细信息

对Si3 N4粉末实现了三种不同压力的冲击波预先处理 ,而后采用三种不同的热压烧结条件制得Si3 N4陶瓷。运用SEM ,TEM ,HRTEM和XRD等手段分析了粉末和陶瓷的结构特性 ,同时测试了材料的性能。结果表明 :冲击波压力没有导致Si3 N4粉末的相变 ,TEM观察表明Si3 N4晶粒中有大量的位错及位错群 ,冲击波的作用主要是通过引入大量位错和其他缺陷促进致密化过程 ,提高陶瓷材料的机械性能。经过40GPa冲击波活化 1 80 0℃热压烧结的Si3 N4陶瓷性能最好 ,弯曲强度达 1 1 0 7.2MPa ,断裂韧性达 1 2 .2 0MPa .m1/2 。

关键词：冲击波活化烧结氮化硅粉末

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《再生缘》艺术特征探析

玉林师范学院学报 2014年第6期35卷 71-76页

作者：蔡瑜清暨南大学文学院广东广州510632

弹词《再生缘》的研究成果比较丰富,但在作品艺术特征的阐释方面还相对薄弱。本文着眼于文本,具体分析《再生缘》表现形式上的特征:《再生缘》运用小说的叙事机理和方法、韵文为主韵散结合的文体形式和雅化的文词演述一个女扮男装的巾... 详细信息

弹词《再生缘》的研究成果比较丰富,但在作品艺术特征的阐释方面还相对薄弱。本文着眼于文本,具体分析《再生缘》表现形式上的特征:《再生缘》运用小说的叙事机理和方法、韵文为主韵散结合的文体形式和雅化的文词演述一个女扮男装的巾帼英杰的故事,达到了叙事性和诗性的完美结合。

关键词：《再生缘》叙事机理文体形式雅化文词