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苏南蚕丝生产改进与近代苏南农村生产结构变迁研究

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中国农史 2018年第2期37卷 48-55页

作者：杨虎李维力江苏科技大学人文社科学院江苏镇江212003

近代中国上海开埠后,苏南地区蚕丝生产得到了较大的发展空间,作为最重要的农村社会经济生产方式,蚕丝生产改进加速了近代苏南农村传统生产结构的瓦解与革新,使其步入近代化之路。新式专业化的蚕种生产冲击了农村中传统土种生产;先进的... 详细信息

近代中国上海开埠后,苏南地区蚕丝生产得到了较大的发展空间,作为最重要的农村社会经济生产方式,蚕丝生产改进加速了近代苏南农村传统生产结构的瓦解与革新,使其步入近代化之路。新式专业化的蚕种生产冲击了农村中传统土种生产;先进的机器缫丝生产方式替代了落后的手工生产方式;大规模集中性工厂化生产方式瓦解了原旧有的分散家庭性生产。

关键词：苏南蚕丝生产改进专业化蚕种生产机器缫丝生产工厂化生产农村生产结构

考虑渠道势力与服务负溢出效应的双渠道供应链决策研究

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管理学报 2017年第5期14卷 767-774页

作者：李伟李凯安岗东北大学工商管理学院

针对双渠道供应链中渠道势力的变化,构建制造商领导的Stackelberg模型(MS模型)、纵向Nash模型(VN模型)和零售商领导的Stackelberg模型(RS模型),并引入服务负溢出效应,考察供应链最优决策和绩效的差异。研究发现:(1)随着服务负溢出效应... 详细信息

针对双渠道供应链中渠道势力的变化,构建制造商领导的Stackelberg模型(MS模型)、纵向Nash模型(VN模型)和零售商领导的Stackelberg模型(RS模型),并引入服务负溢出效应,考察供应链最优决策和绩效的差异。研究发现:(1)随着服务负溢出效应的增强,MS模型下的最优服务水平降低、批发价格上升,VN和RS模型下的最优服务水平不变、批发价格下降;(2)MS模型下,服务负溢出对零售价格的影响与溢出系数有关,VN和RS模型下的服务负溢出使零售价格下降;(3)制造商在MS模型中的利润最高,零售商在不同势力结构下的利润大小取决于服务负溢出系数;(4)在不同渠道势力下,供应链总绩效、直销渠道绩效和传统渠道绩效的变化,主要取决于服务负溢出系数和直销渠道潜在市场份额。

关键词：双渠道供应链渠道势力直销渠道服务负溢出供应链决策

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多组分高分子体系动态流变学研究

高等学校化学学报 1999年第9期20卷 1483-1490页

作者：郑强杨碧波吴刚李立伟浙江大学高分子科学与工程学系杭州310027

根据动态流变学基本理论介绍了多组分高分子体系动态流变学行为，评述了动态流变学方法在研究高分子共混体系、嵌段共聚物体系、填充高分子体系及溶胶-凝胶体系的形态、结构方面的最新进展，认为动态流变学方法是研究多组分高分子体系... 详细信息

根据动态流变学基本理论介绍了多组分高分子体系动态流变学行为，评述了动态流变学方法在研究高分子共混体系、嵌段共聚物体系、填充高分子体系及溶胶-凝胶体系的形态、结构方面的最新进展，认为动态流变学方法是研究多组分高分子体系形态与结构的一种有效方法．

关键词：多组分高分子体系动态流变学结构形态

Metallogenic dynamics of the Yimen-type copper deposits and prediction of concealed ores

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Chinese Science Bulletin 1999年第S2期44卷 250-252页

作者： HAN Rensheng~1, SUN Jiacong~1, GU Xiaochun~2, li Jun~1, li Yuan~1, li wei~1 and MA Deyun~1 1. Kunming University of Science and Technology, Kunming 650093, China 2. Yimen Mining Bureau, Yimen 651101, China Kunming University of Science and Technology Kunming 650093 China Yimen Mining Bureau Yimen 651101 China

1 Geology and origin of the Yimen-type copper deposits THE Yimen copper mining district is located in a rift environment on the margins of the Yangtze continent and occurs in the middle segment of the Wuding-Yimen-Yuanjiang fault depression zone in theProterozoic Kunyang rift, with the Lujijiang fault as the boundary in the west and the Luoci-Yimen faultas the boundary in the east, and in the north it borders on the Luwu copper ore field and in the south itlinks with the Yuanjiang copper deposit, thus constituting an SN-striking elongated basin. Exposed in themining district are mainly the Heishantou, Dalongkou, Meidang, Yingming, Luoxue, Elachang and Lujijiang formations of the Early-Middle Proterozoic Kunyang Group, constituting a suite of lightly metamorphic rocks of low greenschist facies, and locally the Debadu Formation-complexes of the Early Proterozoic-Archean Dahongshan Group. The mining district can be divided into two ore zones: the east ore zone andthe west ore zone. Mainly distributed in the west ore zone are the volcano-sedox-strongly reworked-deepsource superimposed-type ( Fengshan-type) ore deposits, including the Sanjiachang ( including theShishan and Fengshan copper deposits), Yiduochang, Elachang, Tianxing and Meishan copper deposits(occurrences) which are all designated to the typical Yimen-type copper deposits. In the east ore

关键词： metallogenic dynamics prediction of concealed ores Yimen-type copper deposits.

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge wei Xilei liu Dai li Xiaoqi Pang Fanglian Chen Hailong Cao Ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： li-Xu You Lan Tian Chun-ling Guo Shun-Xi li Yu-Cheng liu Yu-Long li wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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复合笼条转子感应电动机不同转子材料特性对起动性能的影响

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中国电机工程学报 2005年第14期25卷 103-108页

作者：曹君慈李伟力齐歌罗应立哈尔滨工业大学电气工程系黑龙江省哈尔滨市150001 华北电力大学电力工程系北京市昌平区102206

利用电磁场理论和变分法建立了复合笼条转子感应电动机起动时二维电磁场的数学模型,给出了利用有限元法求解正弦时变场的方法。在计算过程中,以定子端电压为约束条件,对定子起动电流进行了迭代计算,得到了额定电压下的起动电流和起动转... 详细信息

利用电磁场理论和变分法建立了复合笼条转子感应电动机起动时二维电磁场的数学模型,给出了利用有限元法求解正弦时变场的方法。在计算过程中,以定子端电压为约束条件,对定子起动电流进行了迭代计算,得到了额定电压下的起动电流和起动转矩。以此为基础,改变转子槽形,计算转子不同材料时不同转子结构电机的起动性能。通过方案比较,选取合理的转子槽形和材料,进行样机的加工和试验,把计算结果与实测结果进行对比,表明复合笼条转子感应电动机起动性能的计算结果满足工程实际的需要。同时,将计算结果与普通感应电动机起动性能进行比较,证明复合笼条转子感应电动机具有良好的起动性能。

关键词：复合笼条电动机有限元材料起动性能

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戊型肝炎重叠乙型肝炎感染的临床特征分析

中华医院感染学杂志 2010年第21期20卷 3329-3331页

作者：李蔚莉北京地坛医院急诊科北京100015

目的分析戊型肝炎重叠乙型肝炎感染的临床特征。方法用酶联免疫吸附试验(EliSA)检测戊型肝炎重叠乙型肝炎组、单纯戊型肝炎组和单纯乙型肝炎的肝炎标志物,同时检测生化指标,比较临床症状和并发症。结果重叠组的死亡率、重型肝炎率及自... 详细信息

目的分析戊型肝炎重叠乙型肝炎感染的临床特征。方法用酶联免疫吸附试验(EliSA)检测戊型肝炎重叠乙型肝炎组、单纯戊型肝炎组和单纯乙型肝炎的肝炎标志物,同时检测生化指标,比较临床症状和并发症。结果重叠组的死亡率、重型肝炎率及自发性腹膜炎率均高于乙型肝炎组和戊型肝炎组;重叠组临床症状和戊型肝炎组差异无统计学意义,但比乙型肝炎组严重;重叠组HBeAg阴性率与HBV DNA阳性率和乙型肝炎组比较差异有统计学意义;丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、血清总胆红质(TbiL)和白蛋白(ALB)重叠组和乙型肝炎组比较差异有统计学意义,重叠组和戊型肝炎组除TbiL外均差异不大。结论与单纯HBV和HEV感染比较,戊型肝炎重叠乙型肝炎感染临床症状和肝脏损害更严重,死亡率更高。

关键词：戊型肝炎乙型肝炎酶联免疫吸附试验

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离子液体在超疏水银膜表面的电润湿性能

上海交通大学学报 2011年第12期45卷 1879-1884页

作者：李伟李梅路庆华上海交通大学化学化工学院上海200240

利用银镜反应在玻璃基底上制备了粗糙银膜,组装烷基硫醇后得到超疏水银膜.研究了[Emim][BF4]、[Bmim][BF4]、[Hmim][BF4]、[Hmim][Br]和[Hmim][OTf]等一系列离子液体和不同浓度KCl水溶液在超疏水银膜表面的电润湿性能,分析了离子液体中... 详细信息

利用银镜反应在玻璃基底上制备了粗糙银膜,组装烷基硫醇后得到超疏水银膜.研究了[Emim][BF4]、[Bmim][BF4]、[Hmim][BF4]、[Hmim][Br]和[Hmim][OTf]等一系列离子液体和不同浓度KCl水溶液在超疏水银膜表面的电润湿性能,分析了离子液体中离子体积、离子液体液滴大小,以及超疏水表面组装层的分子结构对其电润湿性能的影响.结果表明,离子液体的电润湿性能与离子体积和电荷偏离有关,与液滴体积无关,相似电导率的离子液体与KCl水溶液具有相似的电润湿性.

关键词：电润湿超疏水离子液体表面张力烷基硫醇