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Effects of resveratrol on the expression and function of p-glycoprotein at the blood-brain barrier in the diabetic mice

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中国药理通讯 2008年第3期25卷 50-50页

作者： Hao Hong Jing Wu Si Si Chen Hui Ji yong qi li Yan Long Yuan Zheng Xia Department of Pharmacology China Pharmaceutical University Nanjing 210009

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi liu Yan-Bo li qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang qian Peng liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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教育博士招生制度的现状、困境与出路

黑龙江高教研究 2025年第1期43卷 98-103页

作者：韦卫起航李祥贵州交通职业大学贵州贵阳551400 西北师范大学甘肃兰州730070 贵州师范大学贵州贵阳550025

教育博士高质量发展是教育强国的战略机遇和教育博士招生规模扩大的时代诉求,完善教育博士招生制度是把好教育博士人才培养“入口关”的重要问题,是提升教育博士人才培养质量的开端。基于2024年31所高校教育博士的招生文本分析可以发现... 详细信息

教育博士高质量发展是教育强国的战略机遇和教育博士招生规模扩大的时代诉求,完善教育博士招生制度是把好教育博士人才培养“入口关”的重要问题,是提升教育博士人才培养质量的开端。基于2024年31所高校教育博士的招生文本分析可以发现,当前教育博士招生制度设计从实质正义和程序公平两个方面体现正义属性,但还存在选拔标准学博趋同、招生指标分配不均、类型特征不够凸显等问题。教育博士招生制度改革,要扣准教育博士类别要求和人才规格定位,从选拔标准应差异化、招生指标应动态化、评价标准应科学化等方面,进一步回应满足面向2035的卓越教师和教育家型教师培养需要。

关键词：教育博士招生制度程序公平实质正义内容分析法

基于SBAS-InSAR和光学遥感的天津市北部山区潜在滑坡识别研究

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灾害学 2025年第1期40卷 30-35页

作者：王勇邢振涛李锁闫勇司甜天津城建大学地质与测绘学院天津300384 天津市地质工程勘测设计院有限公司天津300191

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛... 详细信息

以天津市北部山区为研究对象,开展潜在滑坡识别研究,利用差分干涉测量短基线集时序分析技术(SBAS-InSAR)处理2018-01—2022-08的56景Sentinel-1A数据,并结合2018—2022年的Landsat8光学遥感影像,分析形变与光学遥感影像特征以及NDVI,筛选出潜在滑坡区域。研究结果表明:基于SBAS-InSAR技术识别的天津北部山区的形变较大区域有20处,使用光学遥感影像结合各发育环境要素进行处理确定的区域有19处,其中5处经两种技术确认为滑坡隐患,通过对该5处沉降信息进行识别分析,该5处区域最大年形变速率可达-12 mm/a,需要进行重点监测预警,使用两种技术结合对滑坡隐患区域进行识别可以有效地提高识别准确度,为天津北部山区灾害监测提供新的方式。

关键词：潜在滑坡 SBAS-InSAR 光学遥感影像天津市北部山区

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t-BAMBP萃取分离铷、钾技术的研究

盐业与化工 2016年第11期45卷 15-17页

作者：伊跃军谭秀民张利珍张永兴李琦中国地质科学院郑州矿产综合利用研究所河南郑州450006 国家非金属矿资源综合利用工程技术研究中心河南郑州450006

文章以4-叔丁基2(α-甲苄基)酚(t-BAMBP)为萃取剂,从除钙净化母液中萃取分离铷、钾,考察了稀释剂种类、萃取时间、t-BAMBP浓度、原料碱度、萃取相比等因素对铷、钾分离的影响。对比研究确定的较优工艺条件为:以t-BAMBP为萃取剂,磺化煤... 详细信息

文章以4-叔丁基2(α-甲苄基)酚(t-BAMBP)为萃取剂,从除钙净化母液中萃取分离铷、钾,考察了稀释剂种类、萃取时间、t-BAMBP浓度、原料碱度、萃取相比等因素对铷、钾分离的影响。对比研究确定的较优工艺条件为:以t-BAMBP为萃取剂,磺化煤油为稀释剂,萃取剂浓度为1 mol/L,料液碱度为0.4 mol/L,相比(O/A)为2,萃取时间5 min,铷的萃取率可达90%,实现了铷、钾分离。

关键词： t-BAMBP/磺化煤油萃取体系铷萃取

基于密度泛函理论研究Ag-Co团簇的结构、电子和光学性能

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原子与分子物理学报 2025年第2期42卷 63-69页

作者：李维银尚瑞咏王春勇张永莉北方民族大学电气信息工程学院物理与光电信息功能材料重点实验室微电子与固体电子器件研究中心银川750021

基于密度泛函理论研究了7个原子Ag-Co团簇结构的稳定性、电子和光学性能.研究结果表明,7个原子Ag-Co团簇的最稳定结构都是十面体结构,Co原子数量较少时,Co原子主要占据十面体的轴向位,Ag原子主要占据赤道位,随着Co原子数的增加,Co原子... 详细信息

基于密度泛函理论研究了7个原子Ag-Co团簇结构的稳定性、电子和光学性能.研究结果表明,7个原子Ag-Co团簇的最稳定结构都是十面体结构,Co原子数量较少时,Co原子主要占据十面体的轴向位,Ag原子主要占据赤道位,随着Co原子数的增加,Co原子逐渐替换了赤道位上的Ag原子.当Co原子数增加时,Ag-Co团簇的垂直电离势、垂直电子亲能和最高占据轨道与最低未占据轨道之间的能隙整体上都呈现出下降趋势,表明电子稳定性降低;Ag-Co团簇的吸收光谱整体出现了红移,吸收峰的强度逐渐减弱,吸收谱的宽度变窄.

关键词：银钴团簇几何结构电子性能光学性能

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鹅呼肠孤病毒GRV-LA16株的分离鉴定

中国动物传染病学报 2017年第3期25卷 1-6页

作者：吴巧梅李传峰丁明洋朱杰谭永贵李琦刘光清陈宗艳中国农业科学院上海兽医研究所上海200241

为探明安徽省某养鹅场60日龄鹅出现的软脚,排白色粪便,严重者导致鹅死亡的原因,对病死鹅进行剖检,发现其以肝脏肿大,脾脏肿大和坏死以及肺脏充血、出血为主要特征。对分离毒株进行RT-PCR扩增试验、序列分析及动物回归试验,结果表明,该... 详细信息

为探明安徽省某养鹅场60日龄鹅出现的软脚,排白色粪便,严重者导致鹅死亡的原因,对病死鹅进行剖检,发现其以肝脏肿大,脾脏肿大和坏死以及肺脏充血、出血为主要特征。对分离毒株进行RT-PCR扩增试验、序列分析及动物回归试验,结果表明,该分离毒株为鹅呼肠孤病毒(Goose reovirus,GRV),命名为GRV-LA16株,其ELD50为10-5.7/0.2 m L。病理组织切片结果显示,与对照组相比,肺泡壁胀破融合,毛细血管扩张出血,且肺泡腔有红色丝网状纤维素渗出物。σC基因测序结果分析表明,其与鸭呼肠孤病毒σC基因同源性为87%。GRV-LA16与鸭呼肠孤病毒亲缘关系较近,为同一拓扑群,而与经典的禽呼吸肠孤病毒(Avian orthoreoviruses,ARV)、GRV、番鸭呼肠孤病毒(Muscovy duck reovirus,MDRV)处于不同拓扑群。

关键词：鹅呼肠孤病毒分离鉴定 σC基因

A Signal Based “W” Structural Elements for Multi-scale Mathematical Morphology Analysis and Application to Fault Diagnosis of Rolling Bearings of Wind Turbines

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International Journal of Automation and computing 2021年第6期18卷 993-1006页

作者： qiang li yong-Sheng qi Xue-Jin Gao yong-Ting li li-qiang liu Institute of Electric Power Inner Mongolia University of TechnologyHohhot 010080China Inner Mongolia Key Laboratory of Electrical and Mechanical Control Hohhot 010051China Faculty of Information Beijing University of TechnologyBeijing 100124China

Working conditions of rolling bearings of wind turbine generators are complicated, and their vibration signals often show non-linear and non-stationary characteristics. In order to improve the efficiency of feature extraction of wind turbine rolling bearings and to strengthen the feature information, a new structural element and an adaptive algorithm based on the peak energy are proposed,which are combined with spectral correlation analysis to form a fault diagnosis algorithm for wind turbine rolling bearings. The proposed method firstly addresses the problem of impulsive signal omissions that are prone to occur in the process of fault feature extraction of traditional structural elements and proposes a "W" structural element to capture more characteristic information. Then, the proposed method selects the scale of multi-scale mathematical morphology, aiming at the problem of multi-scale mathematical morphology scale selection and structural element expansion law. An adaptive algorithm based on peak energy is proposed to carry out morphological scale selection and structural element expansion by improving the computing efficiency and enhancing the feature extraction ***, the proposed method performs spectral correlation analysis in the frequency domain for an unknown signal of the extracted feature and identifies the fault based on the correlation coefficient. The method is verified by numerical examples using experimental rig bearing data and actual wind field acquisition data and compared with traditional triangular and flat structural elements. The experimental results show that the new structural elements can more effectively extract the pulses in the signal and reduce noise interference,and the fault-diagnosis algorithm can accurately identify the fault category and improve the reliability of the results.

关键词： Fault diagnosis structural element multi-scale mathematical morphology rolling bearing correlation analysis

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Complex dynamics of a magnetic microrobot driven by single deformation soft tail in random environment

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Theoretical & Applied Mechanics Letters 2024年第5期14卷 402-408页

作者： Xinpeng Shi yongge li yong Xu qi liu School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China MOE Key Laboratory for Complexity Science in Aerospace Northwestern Polytechnical UniversityXi’an 710072China Department of Systems and Control Engineering Tokyo Institute of TechnologyTokyo 152-8552Japan

This study focuses on exploring the complex dynamical behaviors of a magnetic microrobot in a random *** purpose is to reveal the mechanism of influence of random disturbance on microrobot *** paper establishes stochastic dynamic models for the microrobot before and after deformation,considering the influence of Gaussian white *** system responses are analyzed via steady-state probability density functions and first deformation *** effects of different magnetic field strengths and fluid viscosities on the movement speed and angular velocity of the microrobot are *** results indicate that random disturbances can cause deformation of microrobots in advance compared to the deterministic *** work contributes to the design and motion control of microrobots and enhances the theoretical foundation of microrobots.

关键词： Magnetic microrobot Stochastic dynamic models Random disturbances