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1中亚-蒙古造山带东段的锡林郭勒杂岩:早华力西期造山作用的产物而非古老陆块?——锆石SHRIMP U-Pb年代学证据显示文摘锡林郭勒杂岩是华北板块北缘古生代褶皱带内出露面积最大的变质岩系,以前多被当着前寒武纪的古老地块。本文通过对该杂岩中副片麻岩和正片麻岩的锆石SHRIMP U-Pb年代学研究发现,副片麻岩中的锆石多为岩浆锆石,其^(206)Pb/^(238)U加权平均年龄为406±7Ma,指示它们的原岩主要是由近同期(略早些)的岩浆岩风化后就近沉积的产物,该年龄应代表源区(岛弧型?)花岗岩的形成时间,同时也是副片麻岩原岩沉积的下限年龄。正片麻岩中岩浆锆石的^(206)Pb/^(238)U加权平均年龄为382±2Ma,代表花岗片麻岩原岩的侵位年龄。岩石中锆石的变质增生边的形成年龄为337±6Ma,代表锡林郭勒杂岩发生变质和变形的时间,该变质事件可能与贺根山缝合带内所发生的一次主要的碰撞造山作用有关。这些年龄资料充分说明,锡林郭勒杂岩并非古老地块,而是华力西早期岩浆作用、沉积作用和变质作用事件的产物.整个事件是在较短的时间范围内(~70Ma)完成的,推测该杂岩发育在碰撞造山带的弧前环境。中亚-蒙古造山带东南部(内蒙古的中、东部)碰撞前的构造格局可能不是典型的多岛洋体制,由于缺少古老的陆块,造山过程更多的表现为大洋的大陆化过程,即洋内俯冲形成岛弧,岛弧在被动大陆边缘拼贴聚合转化为新的大陆。薛怀民 郭利军 侯增谦 周喜文 童英 潘晓菲 2009岩石学报2009,25,8:63
2黑龙江杂岩的碎屑锆石年代及其大地构造意义显示文摘黑龙江杂岩带位于佳木斯地体西缘,为佳木斯地体向西与松嫩地体之间俯冲、拼贴、碰撞而形成的高压变质带。黑龙江杂岩沿牡丹江断裂分布,其构造-岩石组合、变质变形特征等显示其为佳木斯地体向松嫩地体俯冲拼帖的过程中形成的增生杂岩,目前保存下来的杂岩带应为大规模增生楔仰冲到佳木斯地体之上的残余部分。88颗碎屑锆石的全部样品SHRIMPU-Pb年代学测试结果显示三个主要年龄区间:170~220Ma,峰值年龄为183Ma;240~338Ma,峰值年龄为256Ma;450~520Ma,峰值年龄为470Ma。而28个碎屑锆石谐和年龄的年龄谱为两组:240~338Ma,峰值年龄为256Ma;450~500Ma,峰值年龄为470Ma。碎屑锆石年龄数据分析得到,240~338Ma峰期年龄为256Ma的年龄应代表黑龙江杂岩主体岩石的沉积年龄上限;而450~500Ma的年龄谱对应于佳木斯地体的基底变质岩年龄,显示佳木斯地体的基底变质岩曾为黑龙江杂岩的物源区;而170~210Ma,峰期年龄为183Ma的不谐和年龄应为受印支期-早侏罗世构造热事件的扰动年龄,与该区变质单矿物的Ar-Ar年龄相一致,应代表了该区陆-陆碰撞的时代。上述年龄为黑龙江杂岩的形成与演化提供了重要的地质年代学制约,即黑龙江杂岩的原岩成岩时代上限为早三叠世,佳木斯地体向西的俯冲时代主体为印支期,而陆-陆拼贴及碰撞过程主要为晚印支期并可能持续到早侏罗世。这些结果将为揭示我国东北地区构造演化的年代学格架以及三叠纪古亚洲构造域向环太平洋构造域叠加和转换的动力学背景研究提供新的基本地质事实依据。周建波 张兴洲 Simon A WILDE 郑常青 金魏 陈红 韩杰 2009岩石学报2009,25,8:55
3锡林浩特杂岩和蓝片岩的锆石U-Pb年代学及其对索仑缝合带演化的意义显示文摘报道了内蒙索仑缝合带附近的锡林浩特杂岩和苏左旗混杂带中蓝片岩块的锆石U-Pb年代学数据。锡林浩特杂岩中碎屑锆石来源复杂,从晚太古至晚古生代均有。最年轻的碎屑锆石U-Pb年龄为280~340Ma,与该区最年轻的弧岩浆岩年龄一致,表明该杂岩的原岩最终形成于晚古生代,而不是前寒武陆块残留。锡林浩特杂岩原岩的沉积源区主要是古生代的弧岩浆岩和部分裸露的前寒武陆壳,可能是弧前沉积建造。蓝片岩的锆石U-Pb年龄为318±5Ma(范围338~280Ma),这些锆石显示典型岩浆振荡环带结构,因此该年龄可能代表其原岩形成年龄,而其变质应该在280Ma之后。所以,锡林浩特杂岩和混杂带中蓝片岩块的变质变形作用可能发生在晚二叠,与索仑缝合带强烈的孤陆碰撞有关,暗示索仑缝合带的碰撞缝合时间在晚二叠,而不是许多人坚持的泥盆纪。陈斌 马星华 刘安坤 木合塔尔·扎日 2009岩石学报2009,25,12:47
4Discovery of eclogite inclusions and its geological significance in early Jurassic intrusive complex in Xuzhou-northern Anhui, eastern China显示文摘The early Jurassic intrusive complex is chiefly made of monzodioritic porphyry in northern Anhui and northern Jiangsu, which emplaced in 191 Ma. The intrusive complexes contain a lot of eclogite inclusions which belong to eclogite and garnet-pyroxenite. The inclusions had undergone eclogite facies high-pressure metamorphism and am-phibolite facies retrogressive metamorphism. The garnets in eclogite inclusions are mainly almandine varieties and clino-pyroxenes are omphacite and augite. The mineral assemblage and P-T estimation results show that P-T conditions of eclogite facies metamorphism and amphibolite facies retrogressive metamorphism are over 1.2-1.5 GPa, 709-861°C and 0.7-1.03 GPa, 666-738°C, respectively. The discovery of the high-pressure xenoliths not only is of important significance to understand the composition and structure of deep crust in southern edge of North China Platform, but also can be of important influence on realizing the subduc-tion-collision-exhumation evolutional processWenliang Xu Dongyan Wang Xiaochun Liu Qinghai Wang Jingqian Lin 2002Chinese Science Bulletin2002,47,14:37
5牛呼吸道疾病综合征的主要病原显示文摘近年来,国内外奶牛呼吸系统疾病频发,国外学者将由多种病毒或细菌引起的牛肺炎、运输热、支气管炎等统称为牛呼吸道疾病综合征(Bovinere spiratory disease complex,BRDC)。该病在世界范围内普遍存在,据统计,养牛业中65%的疾病与牛呼吸道疾病相关,感染率达100%,死亡率可达35%或更高。尤其是当病毒性和细菌性病原体相互作用时常会使牛呼吸系统疾病病情加重,导致严重的肺炎。引起BRDC的病毒包括牛传染性鼻气管炎病毒,牛呼吸道合胞体病毒,牛副流感病毒3型等;刘志鹏 董秀梅 师东方 王宇 2012畜牧兽医科技信息2012,28,12:35
6Effect of anti-fibrosis compound on collagen expression of hepatic cells in experimental liver fibrosis of rats显示文摘INTRODUCTIONLiver fibrosis is mainly characterized by theexcessive synthesis and decreased degradation ofextracellular matrix(ECM),especially the synthesisand deposition of collagen.Almost all kinds of cellsin the liver have participated in the production ofcollagen.The most important ones are hepaticstellate cells(HSC)and hepatocytes.WeWang LT Zhang B Chen JJ 2000World Journal of Gastroenterology2000,6,6:31
7黑龙江桦南地区黑龙江杂岩锆石U-Pb定年显示文摘黑龙江杂岩主要由绿片岩相变质岩和糜棱岩化构造片岩组成,长期以来与麻山杂岩一起被认为代表佳木斯地块的前寒武纪基底,但这种认识缺乏可信的同位素年代学及古生物资料的支持。对出露于黑龙江省东部桦南地区湖南营组绿片岩进行了锆石LA-ICP-MS U-Pb定年研究。结果显示锆石的Th/U比值为0.27~1.27,变化较大;获得两组^(206)Ph/^(238)U年龄数据:其加权平均年龄分别为:511±10Ma(n=13,MSWD=1.6)和274.7±3.6Ma(n=9,MSWD=0.91)。黑龙江杂岩中最老的年龄969~747Ma表现来自中元古和新元古代。这些年龄与黑龙江杂岩的年龄与来自俯冲碰撞变质事件的~511Ma的年龄结合起来,表明黑龙江杂岩中含有经历晚新元古——早古生代造山作用的碎屑锆石,亦或代表着在俯冲拼贴过程中混入的麻山杂岩块体。~275Ma年龄反映黑龙江杂岩经历的一次碰撞造山事件,可能与晚古生代古亚洲洋闭合相关。李旭平 焦丽香 郑庆道 董晓 孔凡梅 宋召军 2009岩石学报2009,25,8:30
8Neural mechanism of gastric motility regulation by electroacupuncture at RN12 and BL21: A paraventricular hypothalamic nucleus-dorsal vagal complex-vagus nervegastric channel pathway显示文摘AIM: To study the neural mechanism by which electroacupuncture(EA) at RN12(Zhongwan) and BL21(Weishu) regulates gastric motility.METHODS: One hundred and forty-four adult Sprague Dawley rats were studied in four separate experiments. Intragastric pressure was measured using custommade rubber balloons, and extracellular neuron firing activity, which is sensitive to gastric distention in the dorsal vagal complex(DVC), was recorded by an electrophysiological technique. The expression levels of c-fos, motilin(MTL) and gastrin(GAS) in the paraventricular hypothalamic nucleus(PVN) were assayed by immunohistochemistry, and the expression levels of motilin receptor(MTL-R) and gastrin receptor(GAS-R) in both the PVN and the gastric antrum were assayed by western blotting.RESULTS: EA at RN12 + BL21(gastric Shu and Mu points), BL21(gastric Back-Shu point), RN12(gastric Front-Mu point), resulted in increased neuron-activating frequency in the DVC(2.08 ± 0.050, 1.17 ± 0.023, 1.55 ± 0.079 vs 0.75 ± 0.046, P < 0.001) compared with a model group. The expression of c-fos(36.24 ± 1.67, 29.41 ± 2.55, 31.79 ± 3.00 vs 5.73 ± 2.18, P < 0.001), MTL(22.48 ± 2.66, 20.76 ± 2.41, 19.17 ± 1.71 vs 11.68 ± 2.52, P < 0.001), GAS(24.99 ± 2.95, 21.69 ± 3.24, 23.03 ± 3.09 vs 12.53 ± 2.15, P < 0.001), MTL-R(1.39 ± 0.05, 1.22 ± 0.05, 1.17 ± 0.12 vs 0.84 ± 0.06, P < 0.001), and GAS-R(1.07 ± 0.07, 0.91 ± 0.06, 0.78 ± 0.05 vs 0.45 ± 0.04, P < 0.001) increased in the PVN after EA compared with the model group. The expression of MTL-R(1.46 ± 0.14, 1.26 ± 0.11, 0.99 ± 0.07 vs 0.65 ± 0.03, P < 0.001), and GAS-R(1.63 ± 0.11, 1.26 ± 0.16, 1.13 ± 0.02 vs 0.80 ± 0.11, P < 0.001) increased in the gastric antrum after EA compared with the model group. Damaging the PVN resulted in reduced intragastric pressure(13.67 ± 3.72 vs 4.27 ± 1.48, P < 0.001). These data demonstrate that the signals induced by EA stimulation of acupoints RN12 and BL21 are detectable in the DVC and the PVN, and increase the levels of gastrointestinal hormones and their receptors in the PVN and gastric antrum to regulate gastric motility. CONCLUSION: EA at RN12 and BL21 regulates gastric motility, which may be achieved through the PVN-DVCvagus-gastric neural pathway.Hao Wang Wen-Jian Liu Guo-Ming Shen Meng-Ting Zhang Shun Huang Ying He 2015World Journal of Gastroenterology2015,21,48:27
9AN ENORMOUS THRUST NAPPE AND EXTENSIONAL METAMORPHIC CORE COMPLEX NEWLY DISCOVERED IN SINO-MONGOLIAN BOUNDARY AREA显示文摘An enormous thrust nappe and a metamorphic core complex of extensional origin have been recently discovered within the Hercynian-Indosinian orogen of Inner Mongolia. Both features are of the Mesozoic age, but the former is older. The thrust nappe strikes WNW-ESE and Proterozoic dolomite was thrust southwards atop strata ranging from the Cambrian to the Triassic in age. The visible displacement of the thrust is ca. 70 km and the deduced one is over 140 km. The metamorphic core complex (mainly mylonites) extends in an N-E direction, forming itself into a dome geometry and lying under an extensional detachment fault. The mylonitic foliation dips gently and the stretching mineral lineation, as a whole, plunges SSE. Various shear sense markers show a normal-sense shear movement. Some significant problems atise from the coexistence of nappe and extensional structures at a postoro-genic stage.郑亚东 王士政 王玉芳 1991Science China Chemistry1991,34,9:26
10Multistage Extension and Age Dating of the Xiaoqinling Metamorphic Core Complex,Central China显示文摘There are two extensional systems in the Xiaoqinling metamorphic core complex (XMCC). One is the detachment fault system developed along the peripheries of the XMCC, which extended in an ESE-WNW direction and whose upper plate moved towards the WNW. The other extensional system includes the retrograde shear zones and normal faults developed within the XMCC, which represent the collapse of the XMCC. Ar-Ar and K-Ar dating shows that the extension of the detachment fault system continued from 135 to 123 Ma, i.e. in the late stage of its evolution at about 127 Ma. The collapse represented by the extensional system within the XMCC was operative during 120-106 Ma, and its main activity occurred about 116 Ma ago. These suggest that the XMCC experienced two extensional stages in its evolution, i.e., the syn-orogenic regional extension and post-orogenic collapse extension.ZHANG Jinjiang ZHENG Yadong 1999Acta Geologica Sinica(English Edition)1999,73,2:22
11Late Mesozoic crust-mantle interaction in southeastern Fujian——Isotopic evidence from the Pingtan igneous complex显示文摘UNDERPLATING Of mantle-derived basaltic magma and interacting with the lower crust materials are believed to be an important mechanism for the growth and transformation of the crust.Dong, CW Zhou, XM Li, HM Ren, SL Zhou, XH 1997Chinese Science Bulletin1997,42,6:23
12桐柏地区高压变质地体在地壳中的抬升机制显示文摘桐柏杂岩位于秦岭与大别造山带之间,南北两侧为NWW-SEE向延伸的含榴辉岩高压变质地体,其构造就位过程及其与高压变质地体的构造关系为地质学家们所关注。本文研究表明,所谓的桐柏杂岩实际上是一个早白垩世花岗质片麻岩杂岩体,其内包裹一定数量的三叠纪中高级变质岩石。桐柏杂岩南北两条边界韧性剪切带具有相反的运动学指向,分别为大型右行和左行韧性剪切带,其形成时代为131Ma。这两条韧性剪切带中的剪切面理分别朝SSW和NNE向倾斜,韧性剪切带及杂岩体内部发育的拉伸线理均稳定地朝SEE方向缓倾伏。而在杂岩体的东端发育低角度近南北向韧性剪切变形带,其糜棱面理朝SEE方向低角度缓倾斜,矿物拉伸线理也朝SEE方向低角度缓倾伏,运动学标志指示东侧地质体朝295°~310°的方向逆冲。因此,桐柏杂岩实际上被一个顺造山带的韧性剪切带所围限,这个韧性剪切带及杂岩体内部韧性变形运动学指示了一个早白垩世由东向西的低角度抬升过程,而这一过程直接导致了含榴辉岩高压变质地体沿着造山带的方向从地壳深部抬升到近地表。这一研究结果对理解和认识桐柏-大别-苏鲁地区高压-超高压变质地体的晚期抬升过程具有重要意义。崔建军 胡健民 刘晓春 2009岩石学报2009,25,9:21
13Data mining in Xu Runsan’s Traditional Chinese Medicine practice:treatment of chronic pelvic pain caused by pelvic inflammatory disease显示文摘OBJECTIVE:To research the Traditional Chinese Medicine(TCM)practice of Professor Xu Runsan for treatment of chronic pelvic pain(CPP)caused by sequelae of pelvic inflammatory disease(SPID)by data mining.METHODS:The medical records of inpatients at China-Japan Friendship Hospital confirmed to have CPP caused by SPID were collected(274 visits in total).The data extracted from the medical records were analyzed by frequency statistics,correlation analyses,cluster analyses,and complex network analyses.RESULTS:The most frequently used medicines were warm medicines,bitter medicines,and medicines distributed to the liver meridian.The most common medicinal combinations were Chishao(Radix Paeoniae Rubra)plus Huangqi(Radix Astragali Mongolici)plus Sanqi(Radix Notoginseng)and Ezhu(Rhizoma Curcumae Phaeocoulis);Guizhi(Ramulus Cinnamomi)plus Fuling(Poria)and Chishao(Radix Poeoniae Rubra);and Chaihu(Radix Bupleuri Chinensis)plus Zhishi(Fructus Aurantii Immaturus)and Gancao(Radix Glycyrrhizae).The most frequently used medicines were divided into four groups according to their efficacy;i.e.,medicines that could(a)warm meridians and free collateral vessels,(b)regulate Qi and free collateral vessels,(c)fortify the spleen and nourish blood and Qi,and(d)tonify Qi and activate blood.The most commonly used formulations were Guizhi FulingPill and Sini Powder.The core medicines extracted based on complex network analyses were Chishao(Radix Poeoniae Rubra),Sanqi(Radix Notoginseng),Hua ngqi(Radix Astragali Mongolica),Danshen(Radix Salviae Miltiorrhizae),Ezhu(Rhizoma Curcumae Phaeocaulis), Gancao(Radix Glycyrrhizae),Chaihu(Radix Bupleuri Chinensis),Guizhi(Romulus Cinnomomi),Shuizhi(Hirudo), Fuling(Poria),and Zhishi(Fructus Aurantii Immaturus).CONCLUSION:According to the TCM practice of Professor Xui,treatment of CPP caused by SPID should focus on dissolving stasis and obstructions using medicines that can activate blood,resolve stasis,regulate Qi,and dissipate adhesions.His prescriptions are often based on Guizhi Fuling Pill and Sini Powder.More blood-activating,stasis-resolving,or tonifying medicines could be used according to the accompanying symptoms or symptom patterns identified.Liu Liuqing Yang Fang Xin Ling Jing Yan 2019Journal of Traditional Chinese Medicine2019,39,3:20
14The Zoulang Nanshan Caledonian Subduct ion Complex in the Northern Qilian Mountains and Its Dynamics显示文摘The front of the Zoulang Nanshan Caledonian volcanic island arc zone in the northern Qilian Mountains is a forearc accretionary terrane, composed of multiple accretionary volcanic island arcs, flysch accretionary wedges,high-pressure metamorphosed detachment zones and remnants of ophiolites. It resulted from the northeastward subduction of the Early Palaeozoic Qilan oceanic crust beneath the Alxa block. High-pressure metamorphism, which occurred during the subduction, progressed through three stages: the initial stage of medium T-high P,the main stage of temperature decrease and pressure increase, and the lag stage of pressure decrease and temperature increase. Finally the paper presents a retrotrench subduction dynamic model indicative of northward subduction of the central Qilian block and southward accretion of the Alxa block during the period of 450-500 Ma.Xu Zhiqin, Xu Huifen, Zhang Jianxin, Li Haibing, Zhu Zhizhi, Qu Jingchuan,Institute of Geology, Chinese Academy of Geological Sciences, BeijingChen Daizhang, Chen Jinlu, China University of Geosciences, Beijingand Yang KaichunNo. 2 Q ilian Geological Party, Bureau of Geology and Mineral Resources of Q inghai Province, Q ilian County, Q inghai 1994Acta Geologica Sinica(English Edition)1994,68,3:19
15Overexpressed miRNA-155 dysregulates intestinal epithelial apical junctional complex in severe acute pancreatitis显示文摘AIM:To investigate whether miRNA-155(miR-155)dysregulates apical junctional complex(AJC)protein expression in experimental severe acute pancreatitis(SAP).METHODS:Twenty-four male BALB/c mice were randomly assigned to two groups:the SAP group(n=12)receiving sequential intraperitoneal injection of 50μg/kg caerulein and 10 mg/kg lipopolysaccharide over 6h,and the control group(n=12)receiving intraperitoneal injection of normal saline.Animals were sacrificed3 h following the last injection for collection of blood samples and pancreas and distal ileal segment specimens.Routine pancreas and intestine histology was used to assess SAP pathology and intestinal epithelial barrier damage.Levels of serum amylase,diamine oxidase(DAO),and tumor necrosis factor(TNF)-αwere determined using commercial kits.Total RNA samples were isolated from intestinal epithelial specimens and reversely transcribed into cDNA.miR-155 and RhoA mRNA expression profiles were determined using quantitative real-time polymerase chain reaction.Target genes for miR-155 were predicted using the miRTarBase database,RNA22 and PicTar computational methods.Western blotting was performed to quantitate the protein expression levels of the target gene RhoA,as well as zonula occludens(ZO)-1 and E-cadherin,two AJC component proteins.RESULTS:Intraperitoneal injection of caerulein and lipopolysaccharide successfully induced experimental acute pancreatic damage(SAP vs control,10.0±2.0vs 3.2±1.2,P<0.01)and intestinal epithelial barrier damage(3.2±0.7 vs 1.4±0.7,P<0.01).Levels of serum amylase(21.6±5.1 U/mL vs 14.3±4.2 U/mL,P<0.01),DAO(21.4±4.1 mg/mL vs 2.6±0.8 mg/mL,P<0.01),and TNF-α(61.0±15.1 ng/mL vs 42.9±13.9 ng/mL,P<0.01)increased significantly in SAP mice compared to those in control mice.miR-155 was significantly overexpressed in SAP intestinal epithelia(1.94±0.50 fold vs 1.03±0.23 fold,P<0.01),and RhoA gene containing three miR-155-specific binding sites in the three prime untranslated regions was one of the target genes for miR-155.RhoA(22.7±5.8 folds vs 59.6±11.6 folds,P<0.01),ZO-1(46±18 folds vs68±19 folds,P<0.01),and E-cadherin proteins(48±15 folds vs 77±18 folds,P<0.01)were underexpressed in SAP intestinal epithelia although RhoA mRNA expression was not significantly changed in SAP(0.97±0.18 folds vs 1.01±0.17 folds,P>0.05).CONCLUSION:TNF-α-regulated miR-155 overexpression inhibits AJC component protein syntheses of ZO-1,and E-cadherin by downregulating post-transcriptional RhoA expression,and disrupts intestinal epithelial barrier in experimental SAP.Rui Tian Rui-Lan Wang Hui Xie Wei Jin Kang-Long Yu 2013World Journal of Gastroenterology2013,19,45:19
16扬子克拉通西缘康定杂岩中花岗质岩石的成因及其构造意义显示文摘扬子克拉通西缘康定杂岩中的片麻状花岗岩主要由英云闪长岩、花岗闪长岩、灰白色细粒二长花岗岩和少量的粉红色粗粒二长花岗岩组成。其中英云闪长岩和花岗闪长岩形成于797~795Ma,灰白色细粒二长花岗岩SHRIMP锆石定年产生一个^(206)Pb/^(238)U权重平均767±24Ma,被解释为该期花岗质岩浆的结晶年龄。英云闪长岩、花岗闪长岩和灰白色细粒二长花岗岩和其中的闪长岩包体表现为右斜式稀土配分模式,具有很高的(La/Yb)_N比值,无Eu异常,在原始地幔标准化的多元素蜘蛛网状图上表现了明显的Nb、Ta、P和Ti负异常。而粉红色粗粒二长花岗岩却表现了平坦的稀土配分模式,具有强烈的负Eu异常和强烈的Nh、Ta、Sr、P和Ti负异常,但是富集大离子亲石元素。所有这些片麻状花岗岩具有ε_(Nd)(t)=-0.57~+5.67,绝大部分样品ε_(Nd)(t)>0。结合地质学、岩石学、地球化学和Sm-Nd同位素特征,康定杂岩中英云闪长岩、花岗闪长岩和灰白色细粒二长花岗岩形成于来自亏损地幔的初生地壳玄武质岩石和相关的杂砂岩在高压条件下的部分熔融,而粉红色粗粒二长花岗岩的岩浆导源于表壳岩低压条件下的部分熔融。结合这些片麻状花岗岩的岩石成因和构造鉴别,表明扬子克拉通西缘康定杂岩中新元古代片麻状花岗岩形成于安第斯型活动大陆边缘。刘树文 闫全人 李秋根 王宗起 2009岩石学报2009,25,8:19
17Nd isotopic compositions of the Tethyan Himalayan Sequence in southeastern Tibet显示文摘The Himalayan orogen consists of three major lithologic units that are separated by two major north-dipping faults: the Lesser Himalayan Sequence (LHS) below the Main Central Thrust (MCT), the Greater Himalayan Crystalline Complex (GHC) above the MCT, and the Tethyan Himalayan Sequence (THS) juxtaposed by the South Tibet Detachment fault (STD) over the GHC. Due to widespread meta-morphism and intense deformation, differentiating the above three lithologic units is often difficult. This problem has been overcome by the use of Sm-Nd isotopic analysis. The previous studies suggested that the LHS can be clearly distinguished from the GHC and THS by their Nd isotope compositions. However, the lack of detailed and systematic Sm-Nd isotopic studies of the THS across the Himalaya in general has made differentiation of this unit from the nearby GHC impossible, as the two appear to share overlapping Nd compositions and model ages. To address this problem, we systematically sam-pled and analyzed Nd isotopes of the THS in southeastern Tibet directly north of Bhutan. Our study identifies two distinctive fields in a εNd -TDM plot. The first is defined by the εNd(210 Ma) values of -3.45 to -7.34 and TDM values of 1.15 to 1.29 Ga from a Late Triassic turbidite sequence, which are broadly similar to those obtained from the Lhasa block. The second field is derived from the Early Cretaceous meta-sedimentary rocks with εNd(130 Ma) values from -15.24 to -16.61 and TDM values from 1.63 to 2.00 Ga; these values are similar to those obtained from the Greater Himalayan Crystalline Complex in Bhutan directly south of our sampling traverse, which has εNd(130 Ma) values of -10.89 to -16.32 and Nd model ages (TDM) of 1.73 to 2.20 Ga. From the above observations, we suggest that the Late Triassic strata of the southeast Tibetan THS were derived from the Lhasa block in the north, while the Early Cretaceous strata of the THS were derived from a source similar to the High Himalayan Crystalline Complex or Indian craton in the south. Our interpretation is consistent with the existing palaeocurrent data and provenance analysis of the Late Triassic strata in southeastern Tibet, which indicate the sediments derived from a northern source. Thus, we suggest that the Lhasa terrane and the Indian craton were close to one another in the Late Triassic and were separated by a rift valley across which a large submarine fan was transported southward and deposited on the future northern margin of the Indian continent.DAI JinGen YIN An LIU WenCan WANG ChengShan 2008Science China Earth Sciences2008,51,9:19
18Estimates for the zeros of differences of meromorphic functions显示文摘Let f be a transcendental meromorphic function and g(z)=f(z+c1)+f(z+c2)-2f(z) and g2(z)=f(z+c1)·f(z+c2)-f2(z).The exponents of convergence of zeros of differences g(z),g2(z),g(z)/f(z),and g2(z)/f2(z) are estimated accurately.SHON Kwang Ho 2009Science China Mathematics2009,52,11:18
19Zircon SHRIMP U-Pb ages and trace element geochemistry of the Kuhai gabbro and the Dur'ngoi diorite in the southern east Kunlun tectonic belt, Qinghai, Western China and their geological implications显示文摘Timing of the intermediate-basic igneous rocks developed in the area of Kuhai-A'nyêmaqên along the southern east Kunlun tectonic belt is a controversial issue. This paper presents new zircon SHRIMP U-Pb dating data for igneous zircons from the Kuhai gabbro and the Dur'ngoi diorite in the Kuhai-A'nyemaqen tectonic belt, which are 555±9 Ma and 493±6 Ma, respectively. The trace element geochemical features of the Kuhai gabbro and the Dur'ngoi diorite are similar to those of ocean island basalts (OIB) and island arc basalts (IAB), respectively. Thus, the Kuhai gabbro with the age of 555±9 Ma and OIB geochemical features is similar to the Yushigou oceanic ophiolite in the North Qilian orogen, whereas the Dur'ngoi diorite with the age of 493±6 Ma and IAB geochemical features is similar to the island arc volcanic rocks developed in the north Qaidam. The Late Neoproterozoic to Early Ordovician ophiolite complex in the area of Kuhai-A'nyêmaqên suggests that the southern margin of the 'Qilian-Qaidam-Kunlun' archipelagic ocean in this period was located in the southern east Kunlun tectonic belt. Therefore, the southern east Kunlun tectonic belt in the early Paleozoic is not comparable to the Mianlüe tectonic belt in the Qinling orogenic belt.LI WangYe LI ShuGuang GUO AnLin SUN YanGui ZHANG GuoWei 2007Science China Earth Sciences2007,50,z2:17
20Review on supermolecules as chemical drugs显示文摘Supramolecular medicinal chemistry field has been a quite rapidly developing,increasingly active and newly rising interdiscipline which is the new expansion of supramolecular chemistry in pharmaceu-tical sciences,and is gradually becoming a relatively independent scientific area. Supramolecular drugs could be defined as medicinal supermolecules formed by two or more molecules through non-covalent bonds. So far a lot of supermolecules as chemical drugs have been widely used in clinics. Supermolecules as chemical drugs,i.e. supramolecular chemical drugs or supramolecular drugs,which might have the excellences of lower cost,shorter period,higher potential as clinical drugs for their successful research and development,may possess higher bioavailability,better biocompatibility and drug-targeting,fewer multidrug-resistances,lower toxicity,less adverse effect,and better curative effects as well as safety,and therefore exhibit wide potential application. These overwhelming advan-tages have drawn enormous special attention. This paper gives the definition of supramolecular drugs,proposes the concept of supramolecular chemical drugs,and systematically reviews the recent ad-vances in the research and development of supermolecules,including organic and inorganic complex ones as chemical drugs in the area of antitumor,anti-inflammatory,analgesic,antimalarial,antibacterial,antifungal,antivirus,anti-epileptic,cardiovascular agents and magnetic resonance imaging agents and so on. The perspectives of the foreseeable future and potential application of supramolecules as chemical drugs are also presented.ZHOU ChengHe GAN LinLing ZHANG YiYi ZHANG FeiFei WANG GuangZhou JIN Lei GENG RongXia 2009Science China Chemistry2009,52,4:17
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