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Thermal Behavior,Nonisothermal Decomposition Reaction Kinetics of Mixed Ester Double-base Gun Propellants

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Chemical Research in Chinese Universities 2008年第5期24卷 608-614页

作者： YI Jian-hua ZHAO Feng-qi XU si-yu gao Hong-xu HU Rong-zu Xi＇an Modern Chemistry Research Institute Xi＇an 710065 P. R. China

The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate（TEGDN） and nitroglycerin（NG） were investigated by thermogravimetry（TG） and differential thermogravimetry（DTG）, and differential scanning calorimetry（DSC） under the high-pressure dynamic ambience. The results show that the thermal decomposition processes of the mixed nitric ester gun propellants have two mass-loss stages. Nitric ester evaporates and decomposes in the first stage, and nitrocellulose and centralite II（C2） decompose in the second stage. The mass loss, the DTG peak points, and the terminated temperatures of the two stages are changeable with the difference of the mass ratio of TEGDN to NG. There is only one obvious exothermic peak in the DSC curves under the different pressures. With the increase in the furnace pressure, the peak temperature decreases, and the decomposition heat increases. With the increase in the content of TEGDN, the decomposition heat decreases at 0.1 MPa and rises at high pressure. The variety of mass ratio of TEGDN to NG makes few effect on the exothermic peak temperatures in the DSC curves at different pressures. The kinetic equation of the main exothermal decomposition reaction of the gun propellant TG0601 was determined as： dα/dt=1021.59（1-α）3e-2.60×104/T. The reaction mechanism of the process can be classified as chemical reaction. The critical temperatures of the thermal explosion（Tbe and Tbp） obtained from the onset temperature（Te） and the peak temperature（Tp） are 456.46 and 473.40 K, respectively. ΔS≠, ΔH≠, and ΔG≠ of the decomposition reaction are 163.57 J·mol^-1·K^-1, 209.54 kJ·mol^-1, and 133.55 kJ·mol^-1, respectively.

关键词： Mixed nitric ester gun propellant Triethyleneglycol dinitrate Thermal behaviors Nonisothermal decomposition reaction kinetics

Evaluation of Thermal Hazard of Composite Modified Double-base Propellant by Microcalorimetery Method

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Chemical Research in Chinese Universities 2010年第4期26卷 626-629页

作者： XUE Liang ZHAO Feng-qi XING Xiao-ling XU si-yu PEI Qing gao Yin HU Rong-zu Xi ＇an Modern Chemistry Research Institute Xi ＇an 710065 P. R. China

The thermal decomposition behavior of composite modified double-base（CMDB） propellant containing cyclotrimethylene trinitramine（RDX） was studied via a Calvet microcalorimeter at five different heating rates. The activation energy（E） and the pre-exponential factor（A） of two obvious exothermic processes were obtained by Kissinger＇s method and Ozawa＇s method. The entropy of activation（△S^≠）, the enthalpy of activation（△H^≠）, and the free energy of activation（△G^≠） of the first stage were calculated. To evaluate the thermal hazard of the RDX-CMDB propellant, the critical temperature of thermal explosion（Tb）, the self acceleration decomposition temperature（Tsgox）, the adiabatic decomposition temperature increment（ATad） and the time-to-explosion of adiabatic system（t） were presented as 145.3 ℃, 138.15 ℃, 1634 K and 583.71 s（n=0） and 586.28 s（n=1）, respectively.

关键词： CMDB propellant Microcalorimeter Critical temperature of thermal explosion SADT Adiabatic time-to-explosion

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng gao yu-Gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren yu Guoshu gao yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a silicalite-1(sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the si source. Our approach was effective for synthesizing both sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

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幽门螺杆菌经呼吸道传播的设想

医学争鸣 2018年第2期9卷 14-17,21页

作者：司小北蓝宇高岩北京积水潭医院消化内科北京100035

幽门螺杆菌(***)是一类广泛定植于胃黏膜的微需氧革兰阳性杆菌。目前,关于***传播的机制尚不甚清楚。人对人途径和经水源途径是两种可能的传播途径。除此之外,***还有可能经呼吸道传播。推测经呼吸道传播***可能包含以下过程:第一步,胃... 详细信息

幽门螺杆菌(***)是一类广泛定植于胃黏膜的微需氧革兰阳性杆菌。目前,关于***传播的机制尚不甚清楚。人对人途径和经水源途径是两种可能的传播途径。除此之外,***还有可能经呼吸道传播。推测经呼吸道传播***可能包含以下过程:第一步,胃食管反流液将***从胃黏膜带入食管;第二步,***经过微误吸的方式被带入呼吸道并定植于其表面;第三步,定植于呼吸道的***以飞沫携带的方式呼出感染者体外;第四步,携带***的飞沫被健康人群吸入并定植于其呼吸道;第五步,胃食管反流液将定植于呼吸道的***带入消化道。

关键词：幽门螺杆菌传播呼吸道飞沫

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei Li Qianqian Liang Li Xu Changsheng Ding yu Liu Yanfeng gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(siBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in siBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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上海交通行业人才资源开发的对策与措施

上海海运学院学报 2003年第4期24卷 323-329页

作者：余思勤高德毅上海海运学院经济管理学院上海200135 上海海运学院商船学院上海200135

上海交通行业人才资源开发要以构筑国际化大都市一体化交通、全面提升城市综合竞争力为目标,造就"一流城市,一流交通,一流人才"的格局,到2005年,要达到"三化一适应"。"三化"指经常化、制度化、规范化的上海交通行业人才资源开发的工作... 详细信息

上海交通行业人才资源开发要以构筑国际化大都市一体化交通、全面提升城市综合竞争力为目标,造就"一流城市,一流交通,一流人才"的格局,到2005年,要达到"三化一适应"。"三化"指经常化、制度化、规范化的上海交通行业人才资源开发的工作机制、政策体系、配置制度和信息服务体系。通过"三化"形成尊重知识、尊重人才、鼓励创新和创业的良好氛围,使人才队伍的整体素质得到明显提高。"一适应"则是指适应上海交通事业发展对各类人才资源的需求。

关键词：上海人才资源交通行业人才管理人才规划

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西安市长安区休闲农业发展现状及对策

现代农业科技 2017年第18期 244-245页

作者：刘思余高芬李华斌陕西省西安市长安区农业技术推广中心陕西西安710100 西安市长安区园艺工作站陕西省发展一村一品指导中心

近年来,西安市长安区立足特有的区位优势,大力发展休闲农业,促进农业增效,农民增收。本文介绍了长安区休闲农业发展过程中形成的农家乐、果游园、花卉园、农业科技园4种形式,分析了现阶段长安区休闲农业产业发展中存在的问题,并提出了... 详细信息

近年来,西安市长安区立足特有的区位优势,大力发展休闲农业,促进农业增效,农民增收。本文介绍了长安区休闲农业发展过程中形成的农家乐、果游园、花卉园、农业科技园4种形式,分析了现阶段长安区休闲农业产业发展中存在的问题,并提出了推进休闲农业发展的对策。

关键词：休闲农业现状对策陕西西安长安区