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中心节点距离可控的加权树状网络一致性分析

杭州电子科技大学学报（自然科学版） 2024年第1期44卷 92-96页

作者：李达权孙伟刚杭州电子科技大学理学院浙江杭州310018

选取一类加权树状网络为研究对象,中心节点之间的距离受参数控制。利用其规则的拓扑结构和矩阵知识,得到了网络一致性的精确表达式,着重分析网络权重因子、中心节点之间的距离对网络一致性的影响。研究发现权重越大、两个中心节点之间... 详细信息

选取一类加权树状网络为研究对象,中心节点之间的距离受参数控制。利用其规则的拓扑结构和矩阵知识,得到了网络一致性的精确表达式,着重分析网络权重因子、中心节点之间的距离对网络一致性的影响。研究发现权重越大、两个中心节点之间的距离越短,网络一致性越好。

关键词：网络一致性树状网络网络权重因子

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天然气管道系统目标供气可靠度计算方法

油气储运 2024年第8期43卷 896-904页

作者：姚广玉郑洪龙李大全魏然然孙巧飞杨凯陕西延长石油(集团)管道运输公司国家管网集团科学技术研究总院分公司中国石油尼日尔公司

【目的】天然气管道系统是由众多单元组成的大型、复杂及开放系统,确保安全可靠运行显得尤为重要。随着管道系统可靠性研究的不断深入,系统可靠性指标体系逐渐完善,但尚缺乏有效的系统目标可靠度计算方法,严重制约了天然气管道系统可靠... 详细信息

【目的】天然气管道系统是由众多单元组成的大型、复杂及开放系统,确保安全可靠运行显得尤为重要。随着管道系统可靠性研究的不断深入,系统可靠性指标体系逐渐完善,但尚缺乏有效的系统目标可靠度计算方法,严重制约了天然气管道系统可靠性评价方法的工程实际应用。【方法】提出了一种基于单元可接受风险的天然气管道系统目标供气可靠度计算方法,其包括单元目标可靠度与系统目标供气可靠度两个部分:根据风险可接受准则与风险后果计算方法,构建了基于社会风险与个人风险的管道单元目标可靠度确定模型;考虑天然气管道系统关键单元具有随机失效、气源与用户需求随机波动的特性,构建了基于蒙特卡洛模拟的供气可靠度评价方法,并结合单元目标可靠度计算结果,确定天然气管道系统的目标供气可靠度。【结果】将新建的计算方法应用于中国某天然气管道系统,得到该系统目标供气可靠度为0.999383,将其与基于历史数据统计方法得到的实际供气可靠度0.999404进行对比,评估得出该天然气管道系统可靠度高于目标供气可靠度,能够安全、高效地完成管输任务。【结论】通过实例应用验证了新建计算方法应用于天然气管道系统目标供气可靠度评价的可行性,为后续天然气管道系统可靠性提升与优化研究奠定了技术基础。

关键词：天然气管道供气能力管输任务目标可靠度社会风险个人风险

A murine model for human immune thrombocytopenic purpura and comparative analysis of multiple gene expression in bone marrow and spleen

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Journal of Genetics and Genomics 2008年第11期35卷 665-671页

作者： Hong Wei Xinchun Ding Jiangong Ren Ka liu Pingping Tan daquan li Runlin Z. Ma College of Animal Science and Technology Shihezi University Shihezi 832003 China Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100101 China

Homeostasis of platelet number in human and other mammals is well maintained for prevention of minor bleeding and for other im- munological functions, but the exact molecular mechanism responsible for immune thrombocytopenic purpura （ITP） has not been fully understood. In an effort to identify genetic factors involved in initiation of platelet production in response to bleeding injury or platelet destruction, we have successfully generated an animal model of human ITP via intraperitoneal injection of anti-platelet antibody into the Balb/c mouse. Platelet counts were dropped dramatically in animals that received antibody injection within 4 h, maintained at the mini- mum level for a period of 44 h, started to rebound after 48 h, and reached to the maximum at 144 h （6 days）. Final homeostasis reached at approximately 408 h （17 days）, following a minor cycle of platelet number fluctuation. Using semi-quantitative RT-PCR, we assessed and compared mRNA level of CD41, c-myb, c-mpl, caspase-3, caspase-9, GATA-1, and Bcl-xl in bone marrow and spleen. Alteration of mRNA expression was correlated with the change of platelet level, and an inverse relationship was found for expression of the genes be- tween bone marrow and spleen. No transcription was detectable for any of the seven genes in bone marrow at the time when platelet number reached the maximum （144 h）. In contrast, mRNA transcripts of the seven genes were found to be at the highest level in spleen tissue. This is the first study of simultaneous detection of multiple platelet related genes in a highly reproducible ITP animal model. Our results provided the supportive evidence that expression of the above seven genes are more related to negative regulation of platelet number in spleen tissue, at least in the model animals.

关键词： immune thrombocytopenic purpura murine model semi-quantative RT-PCR

Effects of Ho on the microstructure and mechanical properties of Mg-Zn-Ho-Zr magnesium alloys

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Rare Metals 2011年第2期30卷 131-136页

作者： li daquan WANG Qudong DING Wenjiang National Engineering Research Center for Nonferrous Metals Compositions General Research Institute for Nonferrous Metals Beijing 100088 China National Engineering Research Center of light Alloys Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The microstructure and mechanical properties of Mg-Zn-Ho-Zr alloys have been investigated in detail. The grain size of the as-cast Mg-Zn-Ho-Zr alloy was greatly decreased by the addition of Ho, and the grain growth during solution treatment was suppressed by Mg-Zn-Ho phases formed at grain boundaries. These thermally stable Mg-Zn-Ho phases could not completely dissolve into the matrix dur- ing solution treatment, and the strengthening effect of solution-plus-ageing treatment weakened. The addition of Ho can greatly enhance the high-temperature elongation of the Mg-Zn-Ho-Zr alloy, but the increase of high-temperature tensile strength was just a little.

关键词： magnesium alloys holmium rare earth additions heat treatment microstmcture mechanical properties

Identification of Sheep Ovary Genes Potentially Associated with Off-season Reproduction

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Journal of Genetics and Genomics 2012年第4期39卷 181-190页

作者： Lei Chen Ka liu Zongsheng Zhao Hugh T.Blair Peng Zhang daquan li Runlin Z.Ma College of Animal Science and Technology Shihezi UniversityXinjiang 832000China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Institute of Veterinary Animal and Biomedical Sciences Massey UniversityNew Zealand IGDB-Massey Joint Research Center for Sheep Breeding and Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

Off-season reproduction is a favorable economic trait for sheep industry. Hu sheep, an indigenous Chinese sheep breed, demonstrates a higher productivity of lambs and displays year-around oestrous behavior under proper nutrition and environment. The genetic basis behind these traits, however, is not well understood. In order to identify genes associated with the off-season reproduction, we constructed a suppression subtractive hybridization （SSH） cDNA library using pooled ovary mRNAs of 6 oestrous Hu females as a tester and the pooled ovary mRNAs of 6 non-oestrous Chinese Merino females as a driver. A total of 382 resulting positive clones were obtained after the SSH. We identified 114 differentially up-regulated genes in oestrous Hu sheep by using subsequent screening and DNA sequencing, of which 8 were previously known, 93 were reported for the first time in sheep, and 13 were novel with no significant homology to any sequence in the DNA databases. Functions of the genes identified are related to cell division, signal transduction, structure, metabolism, or cell defense. To validate the results of SSH, 6 genes （Ntrk2, Ppap2b, Htral, Nidl, Serpine2 and Foxola） were selected for conformational analysis using quantitative real-time PCR （qRT-PCR）, and two of them （Htral and Foxola） were verified by Northern blot. All of the 6 genes were differentially up-regulated in the ovary of oestrous Hu. It is obvious that off-season reproduction is a complex trait involving multiple genes in multiple organs. This study helps to provide a foundation for the final identification of functional genes involved in the sheep ovary.

关键词： Hu sheep Suppression subtractive hybridization Oestrous Ovary cDNA library

侧流免疫层析技术在黄曲霉毒素B1检测中的研究进展

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分析科学学报 2023年第3期39卷 367-371页

作者：童璐李大权汪晶浙江工业大学化学工程学院浙江杭州310014

侧流免疫层析技术(lateral flow immunoassay,LFIA),是一种将色谱层析和免疫技术相结合的快速分析方法,为黄曲霉毒素B1(AFB1)的现场快速检测提供了一个良好平台。本文从比色和荧光两种方法介绍了侧流免疫层析技术在AFB1检测中的研究进展... 详细信息

侧流免疫层析技术(lateral flow immunoassay,LFIA),是一种将色谱层析和免疫技术相结合的快速分析方法,为黄曲霉毒素B1(AFB1)的现场快速检测提供了一个良好平台。本文从比色和荧光两种方法介绍了侧流免疫层析技术在AFB1检测中的研究进展,重点阐述不同信号标记材料及其对应方法学,并讨论了目前免疫层析检测的不足及未来发展方向,以期为AFB1的现场即时检测提供参考。

关键词：侧流免疫层析技术黄曲霉毒素B1 信号标记材料生物受体快速检测

Heat Treatment, Microstructure and Mechanical Properties of the Squeezing Cast Al-7.8Zn-2.0Mg-1.6Cu-0.15Zr-0.18Sc Alloy

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稀有金属材料与工程 2011年第S3期40卷 82-85页

作者： Tu Qiang, Yang Fubao, Xu Jun, Zhang Zhifeng, li daquan Nonferrous Metals Processing Division , General Research Institute for Non-ferrous Metals, Beijing 100088, China Gen Res Inst Nonferrous Met Nonferrous Met Proc Div Beijing 100088 Peoples R China

The microstructure of squeezing cast Al-7.8Zn-2.0Mg-1.6Cu-0.15Zr-0.18Sc alloy and those after industrial homogenization treatment and multi-stage solution treatments, were studied by differential scanning calorimetry (DSC), optical microscopy (OM), transmission electron microscope (TEM), scanning electron microscopy with energy dispersive X-ray spectroscopy (TEM-EDX). The results shows that, by complex adding the micro-alloying elements Mn, Sc, Zr, etc ,the microstructure of squeezing casting ingot are fine, uniform, equiaxed, and with the average sizes of 40 μm. The melting point of the non-equilibrium eutectic is 468 ℃ for the casting ingot. After industrial homogenization treatment at 450 ℃ for 24 h, the tensile strength of as-cast alloy is 340-350 MPa and the elongation is 3.5%-4.5%. The multi-stage solution treatment at 465 ℃, 48 h +475 ℃, 8 h +485 ℃, 2 h results in the disappearance of the non-equilibrium eutectics at grain boundary, though some phases containing Fe and Cu can not dissolve completely. After 120 ℃, 24 h aging treatment, the tensile strength is nearly 600 MPa, and the elongation improve to more than 10%.

关键词： squeezing casting homogenization treatment multi-stage solution mechanical properties

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode