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A new hopane triterpenoid from Saxiglossum angustissimum

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Chinese Chemical Letters 2008年第7期19卷 835-836页

作者： hui Fang Pi Zhi Hong Zhong Han Li Ruan peng zhang Yong hui zhang Ji Zhou Wu Faculty of Pharmaceutical Sciences Tongji Medical College of Huazhong University of Science and Technology Wuhan 430030 PR China

A new hopane triterpenoid, hopane 22, 29-diol-29-formate （1）, has been isolated from the whole herbs of Saxiglossum angustissimum （Cries.） Ching and its structure has been successfully determined on the basis of s... 详细信息

关键词： Saxiglossum angustissimum Hopane Hopane-22 29-Diol-29-formate

Does hemorrhoidal artery embolization really benefit patients with hemorrhoids?

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World Journal of Gastroenterology 2024年第42期30卷 4569-4575页

作者： Miao-Lin Lei Li-Li Dong hui-peng zhang Yan-Bo Yu Department of Gastroenterology Laboratory of Translational GastroenterologyQilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina Department of Gastroenterology Affiliated Qingdao Third People’s HospitalQingdao UniversityQingdao 266001Shandong ProvinceChina

This letter offers commentary on an article published in a recent issue of the World Journal of *** artery embolization is a promising approach to severe hemorrhoidal bleeding treatment,but inappropriate patient selection and the use of different embolization procedures may affect the clinical efficacy and cause serious *** this article,the most appropriate candidate patients,embolization materials,embolization methods,and clinical evaluation methods are discussed to improve the safety and effectiveness of the procedure.

关键词： Hemorrhoidal artery embolization Indications Contraindications Complications Effectiveness

Identification of waterflooded zones and the impact of waterflooding on reservoir properties of the Funing Formation in the Subei Basin,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第2期14卷 147-154页

作者： peng-hui zhang Jin-liang zhang Wei-wei REN Jun XIE Ming LI Jing-zhe LI Fang DING Jin-kai WANG Zi-rui DONG College of Resources Science and Technology Beijing Normal University College of Geological Science and Engineering Shandong University of Science and Technology Henan Oilfield Research Institute College of Marine Geosciences Ocean University of China Schlumberger China

This paper describes the identification of waterflooded zones and the impact of waterflooding on reservoir properties of sandstones of the Funing Formation at the Gao 6 Fault-block of the Gaoji Oilfield,in the Subei Basin,east *** work presents a new approach based on a back-propagation neural network using well log data to train the network,and then generating a cross-plot plate to identify waterflooded zones.A neural network was designed and trained,and the results show that the new method is better than traditional *** a comparative study,two representative wells at the Gao 6 Fault-block were chosen for analysis:one from a waterflooded zone,and the other from a zone without *** from this analysis were used to develop a better understanding of the impact of waterflooding on reservoir properties.A range of changes are shown to have taken place in the waterflooded zone,including changes in microscopic pore structure,fluids,and minerals.

关键词： Waterflooding Reservoir properties Neural network Gao 6 Fault-block Gaoji Oilfield

Transcript Regulation of Human Telomerase Reverse Transcriptase by c-myc and mad1

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 32-38页

作者： Lin ZOU~# peng-hui zhang Chun-Li LUO Zhi-Guang TU~* Faculty of Laboratory Medicine,Chongqing University of Medical Sciences.Chongqing 400016,China Faculty of Laboratory Medicine Chongqing University of Medical SciencesChongqing 400016 China

Telomerase activity is highly positive correlated to most malignant *** telomerasereverse transcriptase(hTERT)is the rate-limiting factor of telomerase *** studies have shownthat the expression of hTERT is mainly determined by its transcript *** the transcript regula-tion factors of hTERT,c-myc and mad 1 are well ***,we constructed c-myc and madl eukaryoticexpression vectors,then co-transfected them with the wild-type(Tw)or mutant hTERT promoter(Td)luciferase reporter plasmid,which were double-mutated in the E-box sequences from CACGTG to CACCTGof *** change of luciferase activity in different cells was *** results showed that Tw wasobviously activated in T24 and EJ bladder cancer cells,but not in normal fibrocytes,c-myc and madl hadpositive and negative effects respectively on the Tw transcript in a dose-dependent manner,while the roles ofc-myc and madl in regulating the Td transcript were reversed,c-myc combined with madl can down-regulate Tw but not *** observations indicate that c-myc and madl can regulate the hTERT transcriptin a different manner in hTERT positive cells,but not in normal *** may provide an insight into sometelornerase-related carcinogenesis mechanisms.

关键词： c-myc: mad1 hTERT promoter transcript regulation

New evidence of Silurian hydrocarbon accumulation is discovered by fluid inclusion analysis in the South Yellow Sea Basin

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China Geology 2019年第1期2卷 110-111页

作者： Jie Liang Jian-wen Chen Yin-guo zhang Guang-xi Ou peng-hui zhang Yong Yuan Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Beijing Research Institute of Uranium Geology Beijing 100029China College of Oceanography Hohai UniversityNanjing 210098China

*** Fluid inclusions are the only way to obtain the volatile components in the process of hydrocarbon accumulation. The Marine Paleozoic strata in the South Yellow Sea Basin are of great thickness and widely distributed. The Lower Paleozoic source rocks, reservoirs and caprocks are developed and have generally good hydrocarbon geological conditions.

关键词： evidence inclusion hydrocarbon

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-peng Wang Guo-Cui Mao hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

海域生态承载力评价指标体系研究——以南通市为例

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海洋环境科学 2017年第1期36卷 143-148页

作者：张鹏张惠荣杨红李珺上海海洋大学海洋科学学院上海201306 上海市海洋湖沼学会上海200080 国家海洋局东海环境监测中心上海200137

本论文首先从海域生态承载力的概念和研究方法入手,借鉴国内外相关研究成果,通过指标的多重共线性分析剔除多余指标保留不重叠的指标,构建了海域生态承载力评价指标体系。在计算承载力过程中对原始数据进行无量纲标准化处理。在指标权... 详细信息

本论文首先从海域生态承载力的概念和研究方法入手,借鉴国内外相关研究成果,通过指标的多重共线性分析剔除多余指标保留不重叠的指标,构建了海域生态承载力评价指标体系。在计算承载力过程中对原始数据进行无量纲标准化处理。在指标权重确定的计算过程中运用层次分析法与熵值法相结合的组合权重方法来确定最终权重。在计算过程中,借助yaahp软件来减小人为计算的误差,保证指标权重的科学合理。最后运用状态空间评价模型对南通市所辖海域2009~2014年间的海域生态承载力进行综合评估。研究结果表明:2009~2014年南通市海域生态承载力总体呈现波动式下降趋势,其中2009~2010年间南通市处于良好可载状态,2011~2014年间南通市海域承载力处于基本可载状态。

关键词：海域生态承载力评价指标体系状态空间法

模拟超限车辆荷载作用下既有钢筋混凝土Π梁桥受力性能试验研究

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土木工程学报 2010年第5期43卷 124-135页

作者：张建仁彭晖张克波郝海霞长沙理工大学长沙410076

随着公路交通运输的发展,车辆荷载不断提高,而公路货运中的超限运输情况也非常严重,使得许多旧桥正在承受远远超过其设计荷载等级的重车荷载。过大的车辆荷载致使桥梁结构出现损伤以及承载力退化,严重时甚至引起桥梁垮塌,造成巨大生命... 详细信息

随着公路交通运输的发展,车辆荷载不断提高,而公路货运中的超限运输情况也非常严重,使得许多旧桥正在承受远远超过其设计荷载等级的重车荷载。过大的车辆荷载致使桥梁结构出现损伤以及承载力退化,严重时甚至引起桥梁垮塌,造成巨大生命财产损失。因此,服役多年并存在显著损伤的既有桥梁的实际承载能力成为研究与工程人员关心的重要问题。本文以位于湖南省省道209线上一座服役43年的钢筋混凝土简支梁桥为试验对象,利用千斤顶加载分别模拟超限运输状态下的单车道与两车道20 t、30 t重车荷载,进行了超限车辆荷载作用下的既有梁桥受力性能的试验研究。研究结果表明:达到挠度允许限值时试验桥梁承受的荷载远大于其设计荷载;在一定程度超限车载作用下结构反应仍呈线性;整个超限车载试验过程中桥梁的横向连接刚度变化很小;两车道3倍30 t重车循环加载时结构出现了明显损伤累积。

关键词：模拟超限车辆荷载既有钢筋混凝土梁桥受力性能循环荷载

我国农产品生产集聚的时空格局及影响因素——以蔬菜生产为例

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西北农林科技大学学报（社会科学版） 2017年第6期17卷 81-90页

作者：彭晖张嘉望李博阳西安交通大学经济与金融学院西安710061

利用2002-2013年中国内陆31个省市(区)的面板数据,基于区位商指数分析我国蔬菜生产集聚的变动态势,建立空间面板数据模型,从地理距离和社会经济距离两个不同角度定义空间权重矩阵,对我国蔬菜生产集聚度影响因素和空间相关性进行实证研... 详细信息

利用2002-2013年中国内陆31个省市(区)的面板数据,基于区位商指数分析我国蔬菜生产集聚的变动态势,建立空间面板数据模型,从地理距离和社会经济距离两个不同角度定义空间权重矩阵,对我国蔬菜生产集聚度影响因素和空间相关性进行实证研究。结果表明,我国区域蔬菜生产集中水平具有显著正向空间相关性,经济特征相近的省域之间在蔬菜生产上也具有相互依赖性,但相互依存程度低于地理上相互邻近的省域。相邻区域之间存在较大的空间外溢效应且中部地区(河南、湖北、湖南等)具有高聚集的良性发展态势。影响蔬菜生产集聚的因素有:技术条件、市场需求规模、自然资源及交通运输成本等。

关键词：蔬菜生产空间集聚空间计量外溢效应农产品