检索结果-南通市图书馆

Petrology, geochemistry and Ar-Ar geochronology of eclogites in Jinshajiang orogenic belt, Gonjo area, eastern Tibet and restriction on Paleo-Tethyan evolution

在线全文

学校读者我要写书评

暂无评论

China Geology 2023年第2期6卷 285-302页

作者： Yuan Tang ya-dong qin Xiao-dong Gong Yong Li dong-bing Wang Bao-di Wang Chengdu Center China Geological Survey(Geosciences Innovation Center of Southwest China)Ministry of Natural ResourcesChengdu 610081China China Aero Geophysical Survey and Remote Sensing Center for Natural Resources Beijing 100083China

As one of the important Paleo-Tethys suture zones in eastern Tibet,the Jinshajiang orogenic belt is of great significance to study the tectonic evolution of the main suture zone of *** this paper,eclogites developed in the Jinshajiang suture zone in Gonjo area,eastern Tibet,are selected as specific research objects,and petrological,geochemical and Ar-Ar geochronological analyses are carried *** major element data of the whole rock reveals that the eclogite samples have the characteristics of picritic basalt-basalt and belong to the oceanic low potassium *** results of rare earth elements and trace elements of the samples show that the protoliths of eclogites have characteristics similar to oceanic island basalt(OIB)or normal mid ocean ridge basalt(N-MORB).Muscovite(phengite)from two eclogite samples yield the Ar-Ar plateau ages of 247±2 Ma and 248±2 Ma respectively,representing the peak metamorphic age of eclogite facies and the timing of complete closure of the Jinshajiang Paleo-Tethys *** and biotite selected from the hosting rocks of eclogite yield the Ar-Ar plateau ages are 238±2 Ma and 225±2 Ma respectively,reflecting the exhumation age of eclogites and their hosting *** with the zircon U-Pb dating data(244 Ma)of eclogites obtained in previous work,it can be concluded that the Jinshajiang Paleo-Tethys ocean was completely closed and arc-continent collision was initiated at about 248-244 Ma(T21).Subsequently,due to the large-scale arc(continent)-collision orogeney between Deqin-Weixi continental margin arc and Zhongza block(T31-T32),the eclogites were rapidly uplifted to the shallow crust.

关键词： Eclogite Ar-Ar geochronology Closure of Paleo-Tethys ocean Arc-continent collision Geological survey engineering Jinshajiang orogenic belt Eastern Tibet

A new understanding of Demala Group complex in Chayu Area, southeastern qinghai- Tibet Plateau: Evidence from zircon U-Pb and mica ^(40)Ar/^(39)Ar dating

在线全文

学校读者我要写书评

暂无评论

China Geology 2021年第1期4卷 77-94页

作者： Yuan Tang Yu-ping Liu Peng Wang Wen-qing Tang ya-dong qin Xiao-dong Gong dong-bing Wang Bao-di Wang Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Chengdu Center China Geological SurveyChengdu 610081China

The Chayu area is located at the southeastern margin of the qinghai-Tibet *** region was considered to be in the southeastward extension of the Lhasa Block,bounded by Nujiang suture zone in the north and yarlung Zangbo suture zone in the *** Demala Group complex,a set of high-grade metamorphic gneisses widely distributed in the Chayu area,is known as the Precambrian metamorphic basement of the Lhasa Block in the *** to field-based investigations and microstructure analysis,the Demala Group complex is considered to mainly consist of banded biotite plagiogneisses,biotite quartzofeldspathic gneiss,granitic gneiss,amphibolite,mica schist,and quartz schist,with many leucogranite *** zircon U-Pb ages of two granitic gneiss samples are 205±1 Ma and 218±1 Ma,respectively,representing the ages of their *** zircons from two biotite plagiogneisses samples show core-rim *** U-Pb ages of the cores are mainly 644–446 Ma,1213–865 Ma,and 1780–1400 Ma,reflecting the age characteristics of clastic zircons during sedimentation of the original *** U-Pb ages of the rims are from 203±2 Ma to 190±1 Ma,which represent the age of *** zircon U-Pb ages of one sample taken from the leucogranite veins that cut through granitic gneiss foliation range from 24 Ma to 22 Ma,interpreted as the age of the anatexis in the Demala Group *** and muscovite separates were selected from the granitic gneiss,banded gneiss,and leucogranite veins for 40Ar/39Ar *** plateau ages of three muscovite samples are 16.56±0.21 Ma,16.90±0.21 Ma,and 23.40±0.31 Ma,and the plateau ages of four biotite samples are 16.70±0.24 Ma,16.14±0.19 Ma,15.88±0.20 Ma,and 14.39±0.20 *** mica Ar-Ar ages can reveal the exhumation and cooling history of the Demala Group *** with the previous research results of the Demala Group complex,the authors refer that the Demala Group complex should be a set of metamorphic *** complex in

关键词： Demala Group complex Zircon U-Pb dating 40Ar/39Ar dating Jiali fault zone Geological survey engineering Tibet-qinghai Plateau China

Discovery of eclogites in Jinsha River suture zone, Gonjo County, eastern Tibet and its restriction on Paleo-Tethyan evolution

在线全文

学校读者我要写书评

暂无评论

China Geology 2020年第1期3卷 83-103页

作者： Yuan Tang ya-dong qin Xiao-dong Gong yao-yao Duan Gang Chen Hong-you yao Jun-xiong Liao Shi-yong Liao dong-bing Wang Bao-di Wang Chengdu Center China Geological SurveyMinistry of Natural ResourcesChengdu 610081China Northwest Sichuan Geological Team Sichuan Bureau of Geology and Mineral ExplorationMianyang 621000China No.108 Geological Team Sichuan Bureau of Geology and Mineral ExplorationChengdu 611230China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China

As the important component of the eastern Tethys tectonic region,the Jinsha River-Ailao Mountain suture zone is often considered to be an ophiolitic mé1ange ***,the P-T-t path and chronological framework of the metamorphic evolution in the collisional orogenetic process of this zone are still poorly understood owing to the lack of metamorphism research of symbolic high-pressure *** a regional geological survey on a scale of 1:50000 in Gonjo County,Tibet Autonomous Region involved in this paper,(retrograde)eclogites lenses of different scales were found in Jinsha River suture zone,eastern Tibet for the first ***(retrograde)eclogites can be divided into garnet-albite-chlorite-actinolite schists and eclogites according to retrograde *** mainly mineral components of eclogites include garnet(45%-50%),clinopyroxene(about 25%),and hornblende(5%-10%)primarily,and biotite,quartz,rutile,and muscovite *** to the data of electron probe micro analysis(EPMA),clinopyroxenes feature high content of Na2O(5.6%-6%)and corresponding jadeite(Jd)molecules of 37%-44%,and they fall within the omphacite region in Quad-Jd-Ae *** temperature and pressure of the metamorphism at peak are P≈2.2-2.34 GPa and T≈622-688℃respectively as measured with geobarometry Grt-Omp-Phe and geothermometer *** will provide a new reference for the understanding of Paleo-Tethyan *** this paper,two samples of eclogites were chosen for LA-ICP-MS zircon U-Pb dating and their 206pb/238U ages obtained are 240±3 Ma and 244±1 Ma ***,the zircons feature extremely low Th/U ratio(<0.01),extremely low content ofNb,Ta,and HREE,and invisible negative Eu ***,the genesis of the zircons shall be eclogites-facies metamorphism,indicating that the 240-245 Ma determined in this paper shall be the age of eclogites-facies metamorphism and may represent the westward subduction-collision epoch of Paleo-Tethys Ocean located betwee

关键词： Eclogite Omphacite Jinsha River suture zone Geological survey engineering qinghai-Tibet plateau Eastern Tibet China

在线全文

学校读者我要写书评

暂无评论

循环荷载作用下地基一维非线性固结解析解

岩石力学与工程学报 2006年第1期25卷 21-26页

作者：谢康和周瑾董亚钦浙江大学岩土工程研究所浙江杭州310027

将孔隙比e与有效应力σ′关系(e-lgσ′)引入循环荷载作用下单层地基的一维非线性固结问题的研究之中,通过假定土体中的初始有效应力沿深度均匀分布和固结过程中土体渗透性的降低与压缩性的减小成正比,建立了低频循环荷载作用下单层地... 详细信息

将孔隙比e与有效应力σ′关系(e-lgσ′)引入循环荷载作用下单层地基的一维非线性固结问题的研究之中,通过假定土体中的初始有效应力沿深度均匀分布和固结过程中土体渗透性的降低与压缩性的减小成正比,建立了低频循环荷载作用下单层地基的一维非线性固结问题的固结方程。由ω-σ′变换得出了低频梯形循环荷载作用下单层地基的一维非线性固结问题的解析解,采用Fortran语言编制了相应的计算程序,并通过将其特例情况下的解分别与目前已有的解析解和半解析解进行对比的方法对文中解作了验证。现有单层地基的一维非线性固结解析解均为文中解的特例。

关键词：基础工程一维非线性固结解析解循环荷载

在线全文

学校读者我要写书评

暂无评论

女大学生生殖健康状况及需求

常熟高专学报 2002年第2期16卷 104-106页

作者：董雅勤常熟高等专科学校卫生所江苏常熟215500

采取不记名 ,不公开 ,分组单独询问的方式调查了女大学生对青春期卫生、个人生活习惯、生育。

关键词：女大学生生殖健康状况调查青春期卫生性病

在线全文

学校读者我要写书评

暂无评论

骨科内植入器械手供一体化管理效果分析

临床医学研究与实践 2017年第21期2卷 183-184页

作者：东亚琴陕西省宝鸡市陈仓医院手术室陕西宝鸡721300

目的探究分析骨科内植入器械手供一体化管理效果。方法选取本院2014年10月至2015年10月未实施骨科内植入器械手供一体化管理的350例手术患者为本次研究的对照组,选取本院2015年10月至2016年10月实施骨科内植入器械手供一体化管理的350... 详细信息

目的探究分析骨科内植入器械手供一体化管理效果。方法选取本院2014年10月至2015年10月未实施骨科内植入器械手供一体化管理的350例手术患者为本次研究的对照组,选取本院2015年10月至2016年10月实施骨科内植入器械手供一体化管理的350例手术患者为本次研究的观察组。对两组患者手术器械问题发生率、手术切口感染率以及医师满意度进行对比。结果观察组手术器械问题发生率远低于对照组(P0.05);观察组医师总满意度优于对照组,差异显著(P<0.05)。结论通过对骨科内植入器械实施手供一体化管理,可显著降低手术器械的问题发生率,提高医师的使用满意度,进而提升手术质量。

关键词：骨科内植入器械手供一体化切口感染

ATP及P2X7受体在三伏灸治疗哮喘中的作用

在线全文

学校读者我要写书评

暂无评论

中华中医药杂志 2018年第1期33卷 252-254页

作者：康佩芝陈铭董亚琴福建中医药大学针灸学院福州350108 福建省中医药研究院福州350003

文章通过阐述三磷酸腺苷(ATP)和P2X7受体各自的定义以及两者的关系,分析ATP及P2X7受体与哮喘的联系,并结合三伏灸治疗哮喘的机制,探讨三伏灸对ATP及P2X7受体的影响,推断ATP及P2X7受体在三伏灸治疗哮喘中的作用,推测ATP及P2X7受体对三伏... 详细信息

文章通过阐述三磷酸腺苷(ATP)和P2X7受体各自的定义以及两者的关系,分析ATP及P2X7受体与哮喘的联系,并结合三伏灸治疗哮喘的机制,探讨三伏灸对ATP及P2X7受体的影响,推断ATP及P2X7受体在三伏灸治疗哮喘中的作用,推测ATP及P2X7受体对三伏灸"气至病所"的影响。以此协助哮喘机制的确定、三伏灸疗效的提高,以及"气至病所"理论在临床上的更好运用,从而进一步深入了解中医经络机制的研究,提高哮喘临床诊断治疗水平。

关键词：三磷酸腺苷 P2X7 三伏灸哮喘

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao qin dong Dan Zou Zhijun yang Lili Guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

Observer-based stabilization for singular linear systems with mismatched uncertainties

在线全文

学校读者我要写书评

暂无评论

Observer-based stabilization for singular linear systems wit...