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A study of function mechanism of hemxamethyl tetra-amine in gelation process of uranium

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Rare Metals 2006年第Z1期25卷 343-346页

作者： guo Wenli liang Tongxiang zhao Xingyu HAO Shaochang FU Xiaoming Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

The UO2 ceramic microspheres are the most important materials in the spherical fuel elements for high temperature reactor (HTR). A process for preparation of UO2 kernels known as total gelation process of uranium (TGU) was developed as the production process of 10 mW HTR at Tsinghua University. The TGU process is based on the traditional sol-gel process, external gelation process and internal gelation process of uranium (EGU and IGU), which implies that the gelation action is initiated both by ammonia out of the gel particles and hemxamethyl tetra-amine (HMTA) inside the gel particles. The gelation behavior and the properties of uranium microspheres were investigated of the solution with and without HMTA. It is observed that good spherical particles can be obtained without HMTA in the sol, which indicates a more controllable and industrialized route will be set up. Contrasts between this route and the traditional EGU were also listed.

关键词： gelation process of uranium high temperature reactor (HTR) UO2 microsphere

Preparing UO_2 kernels by gelcasting

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Nuclear Science and Techniques 2009年第2期20卷 124-128页

作者： guo Wenli liang Tongxiang zhao Xingyu HAO Shaochang LI Chengliang Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

A process named gel-casting has been developed for the production of dense UO2 kernels for the high-temperature gas-cooled *** with the sol-gel process,the green microspheres can be got by dispersing the U3O8 slurry in gelcasting process,which means that gelcasting is a more facilitative process with less waste in fabricating UO2 *** UO2 kernels with the size of 500 μm,O/U≤2.01,density of 10.70 g·cm-3 were obtained by gel-casting process followed by heat treatment.

关键词：凝胶注模成型内核高温气冷实验堆铀成型过程溶胶凝胶法 U3O8 高密度

Mechanism underlying the effects of exercise against type 2 diabetes:A review on research progress

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World Journal of Diabetes 2024年第8期15卷 1704-1711页

作者： Chen-Jian Peng Shuo Chen Su-Ying Yan Jian-Ning zhao Zhi-Wen Luo Yuan Qian guo-liang zhao Department of Sports Medicine Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Sports Medicine Huashan HospitalFudan UniversityShanghai 200040China Department of Outpatient Nanjing Hospital of Chinese Medicine affiliated to Nanjing University of Chinese MedicineNanjing 210006Jiangsu ProvinceChina

Exercise has emerged as one of the important and effective non-drug therapies used for management of type 2 diabetes(T2D)in certain *** present report summarizes the latest findings from the research on the beneficial effect of exercise on *** objectives were to provide references for the theoretical study and the clinical practice of exercise-based management of T2D,in addition to identify the limitations of the existing literature,thereby provide direction for future research in this field.

关键词： Type 2 diabetes Diabetes Exercise Mechanism Inflammation

CONSTRUCTION OF A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH POLYNOMIAL LAGRANGIAN MULTIPLIERS

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Journal of Computational Mathematics 2001年第2期19卷 213-224页

作者： Qi-ya Hu (Institute of Computational Mathematics, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences, Beijing 100080, China) guo-ping liang Jin-zhao Liu (Institute of Mathematics, Academy of Mathematics and Systems Sciences, Chinese 中科院计算数学与工程计算数学所北京 100080 中科院数学所北京 100080

In this paper we consider domain decomposition methods with polynomial Lagrangian multipliers to two-dimentional elliptic problems, and construct a kind of simple preconditioners for the corresponding interface equation. It will be shown that condition number of the resulting preconditioned interface matrix is almost optimal (namelys it has only logarithmic growth with dimension of the local interface space).

关键词： Domain Decomposition Non-matching grids Lagrangian multipliers Preconditioner Condition number.

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科技史研究中的“双重标准”现象

自然辩证法研究 2005年第11期21卷 104-107页

作者：梁国钊广西大学社会科学与管理学院广西南宁530004

科技史研究中存在着对同类问题的判定采用“双重标准”的现象。同一作者的“双重标准”是逻辑欠严密,首尾不一贯;不同作者之间存在的“双重标准”现象则是学术观点不同的结果。“双重标准”不利于科学发现优先权的评价,需要通过学术讨... 详细信息

科技史研究中存在着对同类问题的判定采用“双重标准”的现象。同一作者的“双重标准”是逻辑欠严密,首尾不一贯;不同作者之间存在的“双重标准”现象则是学术观点不同的结果。“双重标准”不利于科学发现优先权的评价,需要通过学术讨论统一认识,达至标准统一。

关键词：科技史双重标准诺贝尔奖科学发现

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吴健雄未获诺贝尔奖原因新论

自然辩证法通讯 2007年第4期29卷 96-100页

作者：梁国钊广西大学公共管理学院

吴健雄1957年未能与杨振宁、李政道共同分享当年的诺贝尔物理学奖金,主要原因有两个方面:一是她工作的原创性不够高,她实验的途径与实验设计的关键思路以及实验的关键测量项都是杨振宁、李政道在获奖论文中提出的;二是与她几乎同时、互... 详细信息

吴健雄1957年未能与杨振宁、李政道共同分享当年的诺贝尔物理学奖金,主要原因有两个方面:一是她工作的原创性不够高,她实验的途径与实验设计的关键思路以及实验的关键测量项都是杨振宁、李政道在获奖论文中提出的;二是与她几乎同时、互相独立对弱作用下宇称不守恒作出实验证实的有三个实验小组,诺贝尔评委会不可能厚此薄彼,而一项诺贝尔奖按规定每次至多能授予3人。

关键词：吴健雄诺贝尔奖原因原创性独立发现

Grain boundary effects on spall behavior of high purity copper cylinder under sweeping detonation

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Journal of Central South University 2022年第4期29卷 1107-1117页

作者： YANG Yang HUANG Jun-yi WANG Hai-min CHEN Ji-xiong guo zhao-liang School of Materials Science and Engineering Central South UniversityChangsha 410083China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nonferrous Metals Materials Science and Engineering of Ministry of Education Central South UniversityChangsha 410083China

A series of sweeping detonation experiments were conducted to study the grain boundary effects during the primary spallation of high-purity copper *** free surface velocity profile of the shocked samples was measured by Doppler pins *** soft-recovered samples were characterized by optical and electron backscatter diffraction microscopy,and the effects of microstructures like grain boundaries,and crystal orientation on spall behavior were *** results indicated that the critical stress of deformation twinning in cylindrical copper *** nucleation sites of spallation damage were determined by the joint influence of the grain orientation(Taylor factor)and the angle between grain boundaries and radial impact-stress *** were prone to nucleating at the grain boundaries perpendicular to the radial impact-stress ***,the number of voids nucleated at boundaries was relatively different from the results obtained from the plate impact experiment and plate sweeping detonation experiment,which is a result of the curvature that existed in the cylindrical copper and the obliquity of the impact-stress direction during sweeping detonation loading.

关键词： sweeping detonation high purity copper cylinder spallation microstructure electron backscatter diffraction

Establishing a new testing protocol of the electrochemical stability window for electric double-layer capacitors

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Science China Chemistry 2025年第1期68卷 217-225页

作者： Ruilin Hou Xiaoxi zhao Tingting liang Qingyun Dou Shan Xu Xingbin Yan School of Materials Science and Engineering Sun Yat-sen University Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical Physics Chinese Academy of Sciences College of Engineering and Applied Sciences Nanjing University Center of Industrial Analysis and Testing Guangdong Academy of Science

The electrochemical stability window(ESW) is crucial for determining the energy density of electric double-layer capacitors(EDLCs). However, current ESW testing protocols of EDLCs are strongly affected by artificial factors, thereby leading to unreliable result. To solve this problem, we first identify the key shortcomings of the traditional protocols by analyzing their test principles. Subsequently, taking an aqueous carbon-based EDLC as an example, we design a side reaction descriptor to represent the response difference in the charging capacitance to side reactions between the cyclic voltammetry and galvanostatic chargedischarge methods. With the aid of this descriptor, we propose a new ESW testing protocol, which is not only able to completely avoid the adverse influence of subjective factors but also fully consider the operating condition limitations. The protocol can be extended from the single electrode to the full device. This work proposes a more rigorous definition of ESW and provides a reliable protocol for evaluating the ESW of EDLCs.

关键词： electric double-layer capacitors electrochemical stability window testing protocol side reaction descriptor operating limitation

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开放大学非学历教育质量审视与保障初探

成人教育 2018年第12期38卷 18-25页

作者：国兆亮北京开放大学北京100081

非学历教育是开放大学转型发展的重要抓手和突破点。随着非学历教育规模的扩大,质量问题逐渐凸显。分析了开放大学非学历教育质量现状和质量风险,借鉴《ISO10015国际质量标准培训指南》《欧洲职业教育和培训质量保障参照框架》以及我国... 详细信息

非学历教育是开放大学转型发展的重要抓手和突破点。随着非学历教育规模的扩大,质量问题逐渐凸显。分析了开放大学非学历教育质量现状和质量风险,借鉴《ISO10015国际质量标准培训指南》《欧洲职业教育和培训质量保障参照框架》以及我国《成人教育培训服务通则》等系列国家标准,以提高学员职业能力和素养为目标,以项目培训的基本流程为线索,初步构建了目标—机构—标准—条件—监控一体化的非学历教育质量保障体系框架,并对质量保障的核心内容做了具体的阐述,以期能够促进开放大学非学历教育质量的提升。

关键词：开放大学非学历教育质量保障体系