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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 327-332页

作者： Yu-dong SUN yi-min shi min WU School of Science Guizhou Minzu University Department of Applied Mathematics Northwestern Polytechnical University

In this paper, we study the nonexistence and longtime behavior of weak solution for the degenerate parabolic equation σtun=umdiv（｜▽um｜p-2▽um）＋γ｜▽um｜p＋βun with zero boundary condition. Blow-up time is der... 详细信息

关键词： nonexistence nonlinear degenerate parabolic equations weak solution blow-up

Exact Inference for Joint Type-I Hybrid Censoring Model with Exponential Competing Risks Data

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 645-658页

作者： SONG MAO yi-min shi Xiao-lin WANG Department of Economics and Management Shanxi UniversityTaiyuan 030006China Department of Applied Mathematics Northwestern Polytechnical UniversityXi'an 710072China 78020 Unit Kunming 655000China

Assuming that the failure time under different risk factors follows the independent exponential distribution, a joint model under Type-I hybrid censoring is addressed in detail. Based on the Maximum likelihood estimates （MLEs） of unknown parameters, we obtain exact distributions of MLEs by using the moment generating function （MGF）. Confidence intervals （CIs） of parameters are constructed through both the exact method and the parametric bootstrap method. Then we compare the performances of different methods by Monte Carlo simulations. Finally, the validity of the proposed models and methods are demonstrated by a numerical example.

关键词： Joint Type-I hybrid censoring Competing causes Moment generating function Likelihood inference Bootstrap methods.

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan shi Qun yi Yao Liu yi Huang Key Laboratory of Green Chemical Engineering Process of ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： yi Li Bei-Qi Wang Xin-yin Zhang shi-Jie Wang Cong-yi Li Hui-Long Yang Ran-Ran Su Tong Liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding

基于实数编码自适应遗传算法的整周模糊度快速解算

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航天控制 2017年第3期35卷 14-18页

作者：易清明易夕冬石敏暨南大学信息科学技术学院广州510632

针对整周模糊度解算中实时性不强的问题,提出了一种基于实数编码的自适应遗传算法。首先利用卡尔曼滤波求解整周模糊度的浮点解,然后采用排序和多次(逆)双乔里斯基分解对浮点解及其协方差阵进行降相关处理,降低整周模糊度各分量之间的... 详细信息

针对整周模糊度解算中实时性不强的问题,提出了一种基于实数编码的自适应遗传算法。首先利用卡尔曼滤波求解整周模糊度的浮点解,然后采用排序和多次(逆)双乔里斯基分解对浮点解及其协方差阵进行降相关处理,降低整周模糊度各分量之间的相关性,最后利用已知基线确定模糊度搜索空间,基于实数编码,将自适应遗传算法应用在整周模糊度的搜索解算过程中,求得整周模糊度的最优解。仿真结果表明,本文算法与Lambda算法相比,耗时更少;与简单遗传算法相比,具有更强的收敛能力,是一种高效的整周模糊度快速解算方法。

关键词：整周模糊度卡尔曼滤波乔里斯基分解实数编码自适应遗传算法

Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li Jianhua Huang Di Zhao Lemei Zhu Zheyu Zhang min yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

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不同截面形状薄壁梁的轴向吸能特性研究

机械设计与制造 2017年第7期 190-193页

作者：莫易敏石志华苏东徐敏武汉理工大学机电工程学院湖北武汉430070

以汽车前纵梁结构为研究对象,运用数字模拟仿真和动态试验相结合的方法研究了截面形状对薄壁梁吸能特性的影响。首先在引入平均压溃载荷理论公式基础上,对影响平均压溃载荷的参数特性进行了分析,然后利用HYPERMESH/LS-DYNA非线性有限元... 详细信息

以汽车前纵梁结构为研究对象,运用数字模拟仿真和动态试验相结合的方法研究了截面形状对薄壁梁吸能特性的影响。首先在引入平均压溃载荷理论公式基础上,对影响平均压溃载荷的参数特性进行了分析,然后利用HYPERMESH/LS-DYNA非线性有限元软件对不同截面形状薄壁梁的吸能特性进行碰撞仿真模拟和计算,最后通过落锤试验对模拟仿真结果进行对比分析,验证了各截面参数变化对薄壁梁吸能特性的影响。结果表明:通过增加截面折叠单元(SFE)数目、增加相邻边夹角等措施能够有效提高薄壁梁的吸能特性,使变形模式更加稳定、规则。

关键词：薄壁梁截面形状吸能特性 SFE

Upcycling of polyethylene terephthalate to1,4-cyclohexanedimethanol in water

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Science China Chemistry 2025年

作者： Shuhui Fang Zhiwen Gao Xinrui shi min Zhang Wei Zhang Yue Liu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University Engineering Center for Sustainable Carbon Science and Technology East China Normal University Institute of Eco-Chongming

The recycling of waste polyethylene terephthalate（PET）, an extensively used polymer as plastic and fiber materials, has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment. Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol（CHDM）, an important chemical in the production of advanced polyesters, predominantly use organic solvents, such as alcohols or dioxane. Herein, we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent. In this process, PET is sequentially hydrolyzed in water, hydrogenated to 1,4-cyclohexane dicarboxylic acid（CHDA）, and then reduced to CHDM. The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate. A Pd-based catalyst（e.g., Pd/C） selectively hydrogenates the arene ring of the PET monomer, terephthalic acid intermediate, and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH2OH group. At optimized reaction conditions, a complete conversion of PET and 80.1% yield of CHDM are obtained. Alternatively, this approach can also efficiently produce CHDA from PET, with a yield up to 86.4%.

关键词：

严重事故下开启双层安全壳环形空间通风过滤系统对缓解放射性向环境释放影响研究

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核科学与工程 2016年第4期36卷 504-509页

作者：种毅敏石雪垚杨志义王海洋环境保护部核与辐射安全中心北京100082 中国核电工程有限公司北京100840

核电站发生严重事故后,安全壳能包容从堆芯释放出的裂变产物,防止向环境的大量释放,但即使在安全壳完好的情况下,仍然会存在一定量泄漏。目前国际上的三代核电机型,大多采用双层安全壳的设计,对裂变产物具有一定的包容、滞留和过滤作用... 详细信息

核电站发生严重事故后,安全壳能包容从堆芯释放出的裂变产物,防止向环境的大量释放,但即使在安全壳完好的情况下,仍然会存在一定量泄漏。目前国际上的三代核电机型,大多采用双层安全壳的设计,对裂变产物具有一定的包容、滞留和过滤作用。本文基于我国自主设计的第三代核电机组,结合双层安全壳的设计特点和特定源项分析,对严重事故下双层安全壳之间的环形空间及其通风过滤系统对缓解裂变产物向环境释放的作用进行了定量分析,结果显示双层安全壳及环形空间通风过滤系统能够显著降低放射性气溶胶对环境的释放,对惰性气体也有一定的延缓排放作用。

关键词：双层安全壳通风过滤严重事故放射性释放

基于广州抽水蓄能厂机组全停的电网调度运行策略分析

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南方电网技术 2008年第5期2卷 10-13页

作者：黄志元易仕敏广东省电力调度中心广州510600

广州抽水蓄能厂机组全停将极大威胁电网的安全稳定运行,同时也给调度实时运行带来很大困难。就此,分析了在广州蓄能厂机组全停下的广东电网调度运行策略,提出相应的调峰调频策略,对电网调度实际运行有一定指导意义。

关键词：抽水蓄能调峰调频运行策略事故预案