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Science China Chemistry 2016年第11期59卷 1479-1485页

作者： Jingwen Zhang Xun Guo Sumei Yao xinping qiu Key Lab of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua University

We report a method to eliminate the irreversible capacity of 0.4Li_2MnO_3·0.6LiNi_(0.5)Mn_(0.5)O_2(Li_(1.17)Ni_(0.25)Mn_(0.583)O_2) by decreasing lithium content to yield integrated layered-spinel *** patterns,High-resolution TEM image and electrochemical cycling of the materials in lithium cells revealed features consistent with the presence of spinel phase within the *** discharged to about 2.8 V,the spinel phase of LiM_2O_4(M=Ni,Mn) can transform to rock-salt phase of Li_2M_2O_4(M=Ni,Mn) during which the tetravalent manganese ions are reduced to an oxidation state of *** the spinel phase can act as a host to insert back the extracted lithium ions(from the layered matrix) that could not embed back into the layered lattice to eliminate the irreversible capacity loss and increase the discharge *** electrochemical properties at room temperature showed a high capacity(about 275 mAh g^(-1) at 0.1 C) and exhibited good cycling performance.

关键词： Lithium ion electrode composite materials Lithium-rich material spinel phase layered phase

Stabilized cobalt-free lithium-rich cathode materials with an artificial lithium fluoride coating

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International Journal of Minerals,Metallurgy and Materials 2022年第5期29卷 917-924页

作者： Wei Liu Jinxing Li Hanying Xu Jie Li xinping qiu Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Iron-substituted cobalt-free lithium-rich manganese-based materials,with advantages of high specific capacity,high safety,and low cost,have been considered as the potential cathodes for lithium ion ***,challenges,such as poor cycle stability and fast voltage fade during cycling under high potential,hinder these materials from ***,we developed a method to directly coat LiF on the particle surface of Li_(1.2)Ni_(0.15)Fe_(0.1)Mn_(0.55O2).A uniform and flat film was successfully formed with a thickness about 3 nm,which can effect-ively protect the cathode material from irreversible phase transition during the deintercalation of Li^(+).After surface coating with 0.5wt%LiF,the cycling stability of Li_(1.2)Ni_(0.15)Fe_(0.1)Mn_(0.55O2) cycled at high potential was significantly improved and the voltage fade was largely suppressed.

关键词： cobalt-free lithium-rich cathode materials lithium fluoride coating cycle stability dissolution

PEO-LiClO_4-ZSM5 composite polymer electrolyte(IV):Polarized optical microscopy study

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Science China Chemistry 2005年第6期48卷 574-579页

作者： XI Jingyu qiu xinping ZHU Wentao CHEN Liquan Department of Chemistry Tsinghua University Beijing 100084 China Department of Chemistry Tsinghua University Beijing 100084 China Department of Chemistry Tsinghua University Beijing 100084 China Department of Chemistry Tsinghua University Beijing 100084 China

Polarized optical microscopy (POM) results show that ZSM5 has great influence on both the nucleation stage and the growth stage of PEO spherulites. Part of ZSM5 particles can act as the nucleus of PEO spherulites and thus increase the amount of PEO spherulites. On the other hand, ZSM5 can restrain the recrystallization tendency of PEO chains through Lewis acid-base interaction and hence decrease the growth speed of PEO spherulites. The increasing amount of PEO spherulites, decreasing size of PEO spherulites, and the incomplete crystalliza-tion are all beneficial for creating more continuous amorphous phases of PEO, which is very important for the transporting of Li+ ions. An adequate amount of ZSM5 can enhance the room temperature ionic conductivity of PEO-LiClO4 based polymer electrolyte for more than two mag-nitudes.

关键词： composite polymer electrolyte, poly (ethylene oxide), ZSM-5, polarized optical microscopy, spherulites.

Research on catalysis of sodium-metallochlorophylls in Ni/MH battery

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Chinese Science Bulletin 2009年第17期54卷 3005-3013页

作者： WANG Fang WU Feng CHEN Shi qiu xinping Tianjin Institute of Power Sources Tianjin 300381 China Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China Department of Chemistry Tsinghua University Beijing 100084 China

The effects of sodium-metallochlorophylls including sodium-iron chlorophyllin, sodium-copper chlorophyllin and sodium-magnesium chlorophyllin on performance of Ni/MH battery were investigated. The results show that sodium-iron chlorophyllin can effectively activate the gases produced during charge in Ni/MH battery, therefore reducing the reduction potential of oxygen and the oxidation potential of hydrogen, and the increased speed of inner pressure of battery is decreased significantly. With the aid of DMol3 software, the activation process of oxygen and hydrogen by sodiummetallochlorophylls was simulated and analyzed. It was found that the catalysis behavior is in agreement with the experimental results, and the activation process also gets a reasonable explanation from the calculated results.

关键词：叶绿酸铜钠催化行为氢电池镍激活过程叶绿素氧化氢还原电位

A comparison of iron phthalocyanine and cobalt porphyrin on the electrochemical catalysis in Ni-MH battery

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Chinese Science Bulletin 2007年第1期52卷 71-77页

作者： WANG Fang WU Feng CHEN Shi qiu xinping CHEN LiQuan Department of Chemistry Tsinghua University Beijing 100084 China National Development Center of Hi-Tech Green Materials Beijing 100081 China School of Chemical Engineering and Environmental Science Beijing Institute of Technology Beijing 100081 China

The effects of iron phthalocyanine (FePc) and cobalt porphyrin (CoPp) on inner pressure and cycle behavior of sealed Ni-MH batteries were investigated in this study. The morphology of battery elec- trode was observed by SEM. The electrochemical impedance spectroscopy of floating-charge/dis- charge battery was also measured. Experimental results show that the addition of FePc or CoPp to the alloy electrode is an effective approach to decrease the internal pressure of battery during the process of charge and overcharge. In contrast to CoPp, the battery with FePc exhibits a slower capacity decay and a smaller overpotential at the same charge-discharge rate. As an electrocatalyst, FePc may more effectively speed up the reduction of oxygen, and decrease its reduction potential. As a result, the charge process is accelerated, the gas evolution is reduced and the pulverization of electrode materials is slowed down.

关键词：酞菁染料钢铁钴元素电子化学

Silicon Anode with High Coulombic Efficiency and Cycle Performance

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Silicon Anode with High Coulombic Efficiency and Cycle Perfo...

Zero-Thermal Expansion and Heat Capacity of Zirconium Pyrovanadate Doped with Zirconia and Vanadium (V) Oxide

第31届全国化学与物理电源学术年会

作者： xinping qiu Department of Chemistry Tsinghua University

We have prepared porous Si/C composites with homogeneous silicon particles around 10 nm deposited on porous *** excellent capacity retention may be due to the confinement of SEI inside the *** silicon forms synthesized by a facile template *** morphology and thickness of silicon forms can be controlled by the initial size of nano CaCO template and the parameters of CVD *** volume in this

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Rare Metals 2001年第1期20卷 1-4页

作者： Xianran Xing, Zhenqi Zhu, xinping qiu, Guirong Liu (Dept. of Physical Chemistry University of Science and Technology Beijing, Beijing 100083, China Dept. of Chemistry, Tsinghua University, Beijing 100084, China) 北京科技大学北京 100083 清华大学北京 100084)

The dominant phase ZrV2O7 material, doped with zirconia and vanadium (V) oxide, was synthesized by solid state reaction and sol-gel methods. X-ray power diffraction patterns show that it is cubic structure. Thermal mechanic analysis measurements exhibit a zero-thermal expansion of this material above 150 degreesC. Meanwhile, the heat capacity dependent on temperature, determined by differential scanning calorimetry, keeps in constant almost in the same temperature range. The relationship between unusual thermal expansion and abnormal heat capacity is discussed with Gruneisen parameter.

关键词： zero-thermal expansion of ZrV2O7 heat capacity Gruneisen parameter

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化学反应平衡系统的热容计算

清华大学学报（自然科学版） 1999年第6期39卷 25-27页

作者：朱文涛邱新平清华大学化学系

为了方便精确地计算化学反应系统的热容，以反应进度为基础，建立了理想混合物中化学反应平衡系统的热容计算方法，利用偏摩尔量的性质和热力学基本关系式导出了计算化学反应平衡系统定压热容和定容热等的公式，以碘化氢气相合成反应为... 详细信息

为了方便精确地计算化学反应系统的热容，以反应进度为基础，建立了理想混合物中化学反应平衡系统的热容计算方法，利用偏摩尔量的性质和热力学基本关系式导出了计算化学反应平衡系统定压热容和定容热等的公式，以碘化氢气相合成反应为例，说明如何由化学反应的平衡常数计算平衡反应进度，进而计算压热容和定容热容。计算结果与传统的平稳热容进行比较，二者能较好的符合，计算分析表明了该文所给公式的有效性和实用性。

关键词：定压热容定容热容化学反应热容平衡常数

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数据赋能制造业组织结构创新——基于服装与家具制造企业的双案例研究

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企业经济 2022年第1期41卷 84-93页

作者：邱新平江西财经大学国际经贸学院江西南昌330013

现阶段,企业智能制造应用不断深化,数据量呈现井喷式增长。数据如何在驱动生产过程中对传统生产组织结构产生冲击?聚焦于这一问题,通过双案例研究,本文构建了数据——应用——组织结构创新的理论框架。本文研究发现,生产模块化是支撑个... 详细信息

现阶段,企业智能制造应用不断深化,数据量呈现井喷式增长。数据如何在驱动生产过程中对传统生产组织结构产生冲击?聚焦于这一问题,通过双案例研究,本文构建了数据——应用——组织结构创新的理论框架。本文研究发现,生产模块化是支撑个性化生产的重要前提,物联网应用是强化生产过程协同的关键基础,智能辅助系统应用是促进员工自组织的必要条件。这些发现一方面贡献于智能制造环境下组织结构理论创新,另一方面对中国政府和制造企业数字化转型管理具有一定的启示意义。

关键词：制造业数据赋能组织结构案例研究

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《伤寒论》治疗风湿疼痛经方与临床应用

世界中医药 2023年第9期18卷 1265-1270页

作者：邱新萍北京中医医院顺义医院北京101300

探讨医圣张机《伤寒论》中麻黄类方、桂枝类方、柴胡类方、附子类方治疗风湿病疼痛的经典方剂研究,总结仲景对风湿疼痛的病因病机的认识及治法、用药特点,了解仲景治疗风湿病疼痛首辨表里,善用辛药解表祛邪;重和营卫,调和营卫缓急止痛;... 详细信息

探讨医圣张机《伤寒论》中麻黄类方、桂枝类方、柴胡类方、附子类方治疗风湿病疼痛的经典方剂研究,总结仲景对风湿疼痛的病因病机的认识及治法、用药特点,了解仲景治疗风湿病疼痛首辨表里,善用辛药解表祛邪;重和营卫,调和营卫缓急止痛;善辨虚实,扶正祛邪补虚止痛的辨证思路,旨在使后学者对风湿病疼痛症状的经方治疗有深入认识,以指导临床。

关键词：伤寒论风湿疼痛经方临床应用痹证

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