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Organic Chemistry Frontiers 2022年第5期9卷 1389-1394页

作者： Jiang-xi Yu li-jun Wu Zhi-Qiang wang Zhi-Feng Xu Jin-Heng li Key Laboratory of Functional Meta-Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials(University of Hunan Province)Hengyang Normal UniversityHengyang 421008China College of Sciences Central South University of Forestry and TechnologyChangsha410004China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 475004China

A new method for the synthesis of 3-ethynyl-1-methylene-1,2-dihydronaphthalenes via copper-pro-moted palladium-catalyzed intermolecular alkynylative[5+1]carboannulation of 1-arylphenyl-prop-2-yn-1-yl acetates involving C–H functionalization is *** terminal alkyne molecules serve as an alkynylation reagent and a one-carbon unit to enable alkynylative[5+1]carboannulation with excellent selectivity control,broad substrate scope and good tolerance of functional groups.

关键词： catalyzed Palladium palladium

Oncogenic Wnt3a is a promising sensitive biomarker for monitoring hepatocarcinogenesis

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Hepatobiliary & Pancreatic Diseases International 2023年第3期22卷 263-269页

作者： Min Yao Jian-jun wang xi-Yu Chen Wen-li Sai Jie Yang De-Feng wang li wang Deng-Fu Yao Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityNantong 226001China Department of Immunology Medical School of Nantong UniversityNantong 226001China Nantong Health College of Jiangsu Province Nantong 226016China Department of Molecular Biology Life Science School of Nantong UniversityNantong 226019China Research Center for Intelligence Information Technology of Nantong university Nantong 226019China

Background:The effective treatment for hepatocellular carcinoma(HCC)depends on early ***,the abnormal expression of Wnt3a as the key signaling molecule in the Wnt/β-catenin pathway was found in HCC cells and could be released into the *** this study,we used rat model of hepatocarcinogenesis to dynamically investigate the alteration of oncogenic Wnt3a and to explore its early monitor value for ***:Sprague-Dawley rats(SD)were fed with diet 2-fluorenylacetamide(2-FAA,0.05%)for inducing hepatocarcinogenesis,and grouped based on liver morphological alteration by Hematoxylin&Eosin(H&E)staining;rats fed with normal chow were used as normal control(NC).Total RNA and protein were purified from rat *** expressed genes(DEGs)or Wnt3a m RNA,cellular distribution,and Wnt3a protein levels were analyzed by whole genome microarray with signal logarithm ratio(SLR log 2 cy5/cy3),immunohistochemistry,and enzyme-linked immunosorbent assay,***:Models of rat hepatocarcinogenesis were successfully established based on liver histopathological H&E *** were divided into the cell degeneration(r Deg),precancerosis(r Pre-C)and HCC(r HCC)*** numbers of the up-and down-regulated DEGs with SLR≥8 were 55 and 48 in the r Deg group,268 and 57 in the r Pre-C group,and 312 and 201 in the r HCC group,*** altered genes were involved in cell proliferation,signal transduction,tumor metastasis,and *** with the NC group,Wnt3a m RNA was increased by 4.6 folds(Pliver Wnt3a were 66.7%(P=0.001)in the r Deg group,100%(Pliver Wnt3a(P<0.001)or serum Wnt3a(P<0.001)among different ***:Overexpression of Wnt3a was associated with rat hepa

关键词： Hepatocarcinogenesis Dynamic expression Monitoring Model

The Impact of Urban Expansion on Plant Diversity Change in Karst Regions of Southwest china

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Chinese Geographical Science 2022年第3期32卷 493-505页

作者： YANG Shengtian li Chaojun LOU Hezhen LUO Ya wang Pengfei ZHANG jun li xi WU xijin College of Water Sciences Beijing Normal UniversityBeijing 100875China College of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China

Biodiversity is vital for the integrity and stability of ecosystems and sustainable *** regions of Southwest china is featured for undulating and broken karst terrain as well as high plant *** use changes induced by the growing population and expanding human settlement have threatened biodiversity preservation in this ***,the impact of urban expansion on plant diversity remains unclear *** study focuses on how expanding countryside landscapes affect the recovery rate of plant diversity and demonstrate how urban expansion affects plant diversity conservation in karst regions of Southwest *** situ biodiversity investigations and multisource remote sensing images were combined to analyze the role of human settlement evolution in the conservation of plant diversity using descriptive statistics and regression *** vehicle images,historical aerial photographs,and long-term remote sensing images were used to observe the human settlement pattern changes over 40 yr and found that plant diversity is restored faster in countryside ecosystems than in island ecosystems restricted by ***,however,contribute the most to plant diversity conservation in both *** the forest area is stable during urban expansion,massive forest patches play an essential role in plant diversity *** lands and grasslands shrank but with a fragmenting trend,which was conducive to preserving plant diversity,whereas increased and regularized large patches of built-up areas were not beneficial to plant ***,forest protection should be prioritized to coordinate future socioeconomic development and plant diversity conservation in karst and broader ***,large built-up patches should be limited,and the irregularity should be improved during urban *** shaped cultivated land and grassland were suggested to promote biological information exchanges as landscape corridors.

关键词： plant diversity change urban expansion countryside landscapes karst regions remote sensing china

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油基泥浆下深层储层裂缝表征及有效性评价

西南石油大学学报（自然科学版） 2024年第4期46卷 51-64页

作者：杨凤来陈蓉周庆王俊代力中国石油塔里木油田公司新疆库尔勒841000 中国石油集团测井有限公司地质研究院陕西西安710021

库车地区发育典型的裂缝性致密砂岩储层,岩性致密,孔隙度低,裂缝是否有效是好储层形成的关键因素。因此,如何准确识别裂缝及评价其有效性是油田勘探开发面临的首要问题。由于钻井工程的需要,库车地区大部分井采用油基泥浆钻井。油基泥... 详细信息

库车地区发育典型的裂缝性致密砂岩储层,岩性致密,孔隙度低,裂缝是否有效是好储层形成的关键因素。因此,如何准确识别裂缝及评价其有效性是油田勘探开发面临的首要问题。由于钻井工程的需要,库车地区大部分井采用油基泥浆钻井。油基泥浆导电性能差,且早期的油基泥浆电成像测井仪器受分辨率限制,很难有效识别裂缝,因此,利用油基泥浆电成像测井仪与超声成像仪相结合进行构造的提取与不同张开度裂缝的拾取,可有效解决层理与裂缝精细识别问题。介绍了利用非传导泥浆地质成像仪识别裂缝方法,并系统分析裂缝面法向应力、裂缝走向与最大主应力夹角与产能的关系,建立了库车地区评价油基泥浆裂缝有效性的定量标准。在实际应用中,本套裂缝精细识别及有效性评价方法可有效地指导生产作业措施,为裂缝性致密油气藏的评价与开发提供技术手段。

关键词：油基泥浆致密砂岩电成像测井裂缝面法向应力有效性评价

草地植被冠层与根系对黄土坡面侵蚀过程的影响

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生态学报 2024年第15期44卷 6841-6853页

作者：陈浩王豆豆崔钦凯王博刘俊娥李占斌延安大学生命科学学院延安716000 西安理工大学水利水电学院西安710048 陕西省区域生物资源保育与利用工程技术研究中心延安716000 陕西师范大学地理科学与旅游学院西安710119

草地植被能有效控制坡面侵蚀,然而不同草地植被类型及其冠层与根系对坡面侵蚀过程的调控作用尚缺乏系统研究。采用人工模拟降雨方法,定量研究了不同雨强下苜蓿与黑麦草冠层与根系对黄土坡面侵蚀过程、径流侵蚀动力及土壤抗侵蚀能力特征... 详细信息

草地植被能有效控制坡面侵蚀,然而不同草地植被类型及其冠层与根系对坡面侵蚀过程的调控作用尚缺乏系统研究。采用人工模拟降雨方法,定量研究了不同雨强下苜蓿与黑麦草冠层与根系对黄土坡面侵蚀过程、径流侵蚀动力及土壤抗侵蚀能力特征的影响。结果表明:与裸坡相比,苜蓿与黑麦草的平均减流效益分别为17.65%和9.80%,减沙效益分别为63.86%和69.88%。不同雨强下两种草被根系减流减沙的平均相对贡献均高于冠层,且根系减沙的相对贡献随雨强的增加而增大。草地植被主要通过削减坡面径流流速和增加坡面阻力的方式实现对降雨径流侵蚀动力的调控,草被根系对坡面径流的减速作用略大于冠层,但其增阻作用却明显小于冠层。黑麦草对坡面径流的减速增阻效益高于相同部位的苜蓿。坡面土壤侵蚀率与水流切应力的关系可用幂函数y=αx^(β)较好地拟合。幂函数系数α解释为单位水流切应力所引起的土壤侵蚀模数,可作为反映土壤抗侵蚀能力的指标。草被根系作用下的幂函数系数减幅远高于冠层,反映了其增强土壤抗侵蚀能力作用明显高于冠层,这主要源于草被根系结构对表层土壤性质的改善。须根系黑麦草强化土壤抗侵蚀能力优于直根系苜蓿。本研究揭示了草地植被调控坡面侵蚀过程是通过地上冠层与根系的共同作用达到同时调控侵蚀动力和土壤抗侵蚀能力实现的,草被根系对坡面侵蚀控制起主导作用,且以须根系草被对黄土坡面侵蚀的调控效果最佳。上述结果可为草地侵蚀过程研究及黄土高原草被建设与管理提供科学依据。

关键词：土壤侵蚀过程水动力学参数土壤抗侵蚀能力冠层根系黄土高原

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新型超声波混凝土结构层析成像检测系统的设计

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无损检测 2008年第11期30卷 832-834,837页

作者：王明伟李秦君姚展陕西科技大学电气与信息工程学院西安710021 咸阳师范学院物理系咸阳712000

常规超声波混凝土检测仪仅采用一维超声信号,直观性差,分析依赖于人工判读,为此开发了一种新型混凝土结构层析成像检测系统。系统采用ARM技术和linux操作系统设计,具有层析成像的功能,可以直观显示混凝土内部结构的强度分布和缺陷的位... 详细信息

常规超声波混凝土检测仪仅采用一维超声信号,直观性差,分析依赖于人工判读,为此开发了一种新型混凝土结构层析成像检测系统。系统采用ARM技术和linux操作系统设计,具有层析成像的功能,可以直观显示混凝土内部结构的强度分布和缺陷的位置。系统采用12通道数据同步接收,改进的ART层析成像反演算法,具有较高的收敛速度和精度,使得系统能够在现场实时地给出成像结果,方便了现场检测中的验证和重测。

关键词：超声层析成像混凝土结构检测电路

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中国和古巴男排运动员双人拦网技术的比较

体育学刊 2003年第5期10卷 121-123页

作者：李毅钧赵歌华南师范大学体育科学学院广东广州510631 西安电子科技大学体育部陕西西安710069

通过三维高速录像对中国和古巴两国男排运动员双人拦网技术动作的分析表明:当对方4号位强攻扣球时,2号位队员面对球网并步移动起跳拦网,3号位队员左肩斜对网跑步移动起跳空中转体拦网。古巴运动员拦网时重心腾空高,手臂与网垂直面夹角小... 详细信息

通过三维高速录像对中国和古巴两国男排运动员双人拦网技术动作的分析表明:当对方4号位强攻扣球时,2号位队员面对球网并步移动起跳拦网,3号位队员左肩斜对网跑步移动起跳空中转体拦网。古巴运动员拦网时重心腾空高,手臂与网垂直面夹角小,两臂主动用力前伸下压两手压腕罩球,躯干收腹呈"<"型,拦网攻击性强。

关键词：男排运动员拦网中国古巴

采用叉排管束模型的刷式密封刷丝束变形特性研究

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西安交通大学学报 2024年第9期58卷 48-61页

作者：宋鹏飞屈杰高庆李志刚李军西安交通大学叶轮机械研究所西安710049 西安热工研究院有限公司西安西热节能技术有限公司西安710054 高效灵活煤电及碳捕集利用封存全国重点实验室北京100031

采用刷式密封三维叉排管束泄漏流动数值模拟与有限元分析模型相结合的流固耦合方法,研究了刷丝束在气动载荷作用下的变形特性。通过数值求解三维雷诺时均Navier-Stokes(RANS)方程组和SSTk-ω湍流模型,获得了刷丝束气动载荷,刷丝束有限... 详细信息

采用刷式密封三维叉排管束泄漏流动数值模拟与有限元分析模型相结合的流固耦合方法,研究了刷丝束在气动载荷作用下的变形特性。通过数值求解三维雷诺时均Navier-Stokes(RANS)方程组和SSTk-ω湍流模型,获得了刷丝束气动载荷,刷丝束有限元接触模型综合考虑了刷丝束内部存在的摩擦接触力。研究表明:随着压比的增大(1.5~3.0),刷式密封泄漏流量系数增大的趋势逐渐减缓,第5~9排刷丝承受压差占比从60%增长至70%,转速对刷式密封泄漏流场影响微弱。刷丝所受周向和径向气流力大小相当,二者合力方向与刷丝垂直,轴向气流力则是周向、径向气流力的13.6~18倍。较大轴向气流力使刷丝在围栏高度区域向下游发生轴向弯曲,压比为1.5、2.0、2.5和3.0时,刷丝束最大轴向变形量分别为0.077、0.096、0.114和0.130mm。较小周向、径向力以及后排刷丝与后夹板之间较大摩擦接触力,使刷丝周向和径向变形量很小。刷丝束所受轴向气流力与法向气流力的比值可用于分析刷丝周向变形滑移。所建立的基于刷式密封叉排管束模型的流固耦合方法为分析刷丝束变形特性提供了研究途径。

关键词：刷式密封刷丝束三维叉排管束变形

Feature detection of triangular meshes via neighbor supporting

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Journal of Zhejiang university-Science C(Computers and Electronics) 2012年第6期13卷 440-451页

作者： xiao-chao wang jun-jie CAO xiu-ping liU Bao-jun li xi-quan SHI Yi-zhen SUN School of Mathematical Sciences Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment School of Automotive EngineeringFaculty of Vehicle Engineering and MechanicsDalian University of TechnologyDalian 116024China Department of Mathematical Sciences Delaware State UniversityDoverDE 19901USA

We propose a robust method for detecting features on triangular meshes by combining normal tensor voting with neighbor supporting. Our method contains two stages： feature detection and feature refinement. Firsts the normal tensor voting method is modified to detect the initial features, which may include some pseudo features. Then, at the feature refinement stage, a novel salient measure deriving from the idea of neighbor supporting is developed. Benefiting from the integrated reliable salient measure feature, pseudo features can be effectively discriminated from the initially detected features and removed. Compared to previous methods based on the differential geometric property, the main advantage of our method is that it can detect both sharp and weak features. Numerical experiments show that our algorithm is robust, effective, and can produce more accurate results. We also discuss how detected features are incorporated into applications, such as feature-preserving mesh denoising and hole-filling, and present visually appealing results by integrating feature information.

关键词： Feature detection Neighbor supporting normal tensor voting Salient measure

Protective effects of ligustrazine,Kakonein and Panax Notoginsenoside on the small intestine and immune organs of rats with severe acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2011年第6期10卷 632-637页

作者： xi-Ping Zhang,jun Jiang,Qi-Hui Cheng,Qian Ye,Wei-Juan li,Hua Zhu and jun-Ya Shen Department of General Surgery,Department of Gynecology and Obstetrics and Central Laboratory Department,Hangzhou First People’s Hospital,Hangzhou 310006,china Zhejiang Chinese Medical university,Hangzhou 310053,china Department of General Surgery Hangzhou First People's Hospital Hangzhou 310006 China Zhejiang Chinese Medical university Hangzhou 310053 China Department of Gynecology and Obstetrics Hangzhou First People's Hospital Hangzhou 310006 China Central Laboratory Department Hangzhou First People's Hospital Hangzhou 310006 China

BACKGROUND:Severe acute pancreatitis (SAP) is characterized by fatal pathogenic conditions and a high *** is important to study SAP complicated with multiple organ *** this study we compared the protective effects of three traditional Chinese medicines (ligustrazine,Kakonein and Panax Notoginsenoside) on the small intestine and immune organs (thymus,spleen and lymph nodes) of rats with SAP and explored their mechanism of ***:One hundred forty-four rats with SAP were randomly divided into model control,ligustrazine-treated,Kakonein-treated,and Panax Notoginsenoside-treated groups (n=36 per group).Another 36 normal rats comprised the sham-operated *** to the different time points after operation,the experimental rats in each group were subdivided into 3-,6-and 12-hour subgroups (n=12).At various time points after operation,the mortality rate of rats and pathological changes in the small intestine and immune organs were recorded and the serum amylase levels were ***:Compared to the model control groups,the mortality rates in all treated groups declined and the pathological changes in the small intestine and immune tissues were relieved to different *** serum amylase levels in the three treated groups were significantly lower than those in the model control group at 12 *** pathological severity scores for the small intestinal mucosa,thymus and spleen (at 3 and 12 hours) in the ligustrazine-treated group,for the thymus (at 3 and 12 hours) and spleen (at 3 and 6 hours) in the Kakonein-treated group,and for the thymus (at 3 hours)and spleen (at 3 hours) in the Panax Notoginsenoside-treated group were significantly lower than those in the model control *** pathological severity scores of the small intestinal mucosa (at 6 and 12 hours) and thymus (at 6 hours) in the ligustrazine-treated group were significantly lower than those in the Kakonein-and Panax Notoginsenoside-treated ***:All the t

关键词： severe acute pancreatitis traditional Chinese medicine small intestine multiple organs apoptosis