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1323篇 您的检索式:作者名="Williams Y"
    题名 作者 年代 出处 被引量
1东准噶尔盆地巴塔玛依内山组火山岩锆石U-Pb年代及Hf同位素研究显示文摘对准噶尔盆地陆梁隆起东部三参1井所钻巴塔玛依内山组玄武岩,开展了详细锆石内部结构研究基础上的U-Pb年代学、微量元素和Hf同位素系统分析.结果显示,所有锆石都属岩浆成因,都有一致的稀土配分型式,都具明显的Ce正异常(δCe=5.06~134)、Eu负异常(δEu=0.06~0.55)和重稀土元素富集特征.25颗锆石中,谐和年龄主要分成3组,分别是(300.4±1.3)Ma(n=11),(339.2±2.7)Ma(n=3)和(392.0±1.7)Ma(n=8);此外,还有3颗近谐和年龄锆石,它们的206Pb/238U年龄分别是(510±7),(488±6)和(453±6)Ma.最小的谐和年龄为(300.4±1.3)Ma,可以代表巴塔玛依内山组火山岩的形成时代(如晚阶段年龄).其他年龄如早泥盆世、奥陶纪等,与盆地周缘岛弧火山岩(富集Pb)和蛇绿岩的时代一致,而且这些年龄锆石都具有正的εHf(t)值(+3.6^+10.5),推测所研究火山岩穿越的盆地基底,可能与由早古生代-中古生代的残余洋壳和岛弧地体组成有关.晚石炭世锆石的εHf(t)值变化于+17.1^+4.2,显示该玄武岩主要来源于软流圈地幔或亏损岩石圈地幔熔融作用,熔体在上升-侵位过程中混染了少量较古老基底物质组分.由于这些玄武岩是后碰撞幔源岩浆直接加入到地壳的物质表现,推测东准噶尔地区晚石炭世已经有了大规模的陆壳垂向生长过程.苏玉平 郑建平 Griffin William L 汤华云 O'Reilly Suzanne Y 林向洋 2010科学通报2010,55,30:50
2Zircon U-Pb and Hf isotopes of volcanic rocks from the Batamayineishan Formation in the eastern Junggar Basin显示文摘内部结构的研究被进行从 Batamayineishan 形成调查 U-Pb 年龄,踪迹元素和玄武岩的锆石的 Hf 同位素。暗岩从练习井圣罐头被获得 1 在 Junggar 盆以内在东方 Luliang 上高举。跟踪所有样品是 magmatic 的锆石表演的元素数据,与类似的 REE 模式,包括积极 Ce (Ce=5.06134 ) ,而是否定 Eu (Eu=0.06 ? 0.55 ) 在重稀土元素元素的异例和丰富。在 25 谷物之中,一致年龄被细分进三个组;300.4 整潲祺潧整的年龄?SU YuPing ZHENG JianPing GRIFFIN William L TANG HuaYun O'REILLY Suzanne Y LIN XiangYang 2010Chinese Science Bulletin2010,55,36:21
3古老大陆岩石圈地幔再循环与蛇绿岩中铬铁矿床成因显示文摘不同地区、不同时代蛇绿岩中不同类型铬铁矿岩的Re-Os同位素研究表明,在铬铁矿石或围岩中均存在极度亏损的具有大陆岩石圈地幔属性的物质。新疆达拉布特古生代蛇绿岩带中萨尔托海富Al铬铁矿岩的Os同位素组成为0.1109~0.1256,对应的模式年龄为3.5~0.6Ga;西藏班公湖—怒江中生代蛇绿岩带中东巧富Cr铬铁矿石及围岩Os同位素组成介于0.1175~0.1261,对应的模式年龄为1.5~0.1Ga;雅鲁藏布江中生代蛇绿岩带中罗布莎富Cr铬铁矿岩的Os同位素变化范围为0.1038~0.1266,对应的模式年龄为3.37~0.28Ga,而该带中不含矿的泽当二辉橄榄岩的Os同位素组成为0.1256~0.1261,没有古老大陆岩石圈地幔属性的物质存在,与新特提斯洋地幔Os组成较为接近。推测在蛇绿岩形成过程中,古老大陆岩石圈地幔参与循环有利于形成铬铁矿床,明确提出'熔体与古老大陆岩石圈地幔反应成矿'的假说,指出蛇绿岩带中存在的古老微陆块可能是找矿的指示标志。史仁灯 黄启帅 刘德亮 樊帅权 张晓冉 丁林 William L GRIFFIN Suzanne Y O'REILLY 2012地质论评2012,58,4:15
4沪宁杭地区城市群发展规划探索显示文摘在全球经济一体化的背景下,世界经济中心是在一批具有重大影响的城市群区域。我国许多省市正在编制城市群规划,出现了城市群潮涌神州的新局面。然而城市群区的空间发展规划需要探索的问题不少。以沪宁杭地区为典型例证,就城市群规划的指导思想与总体思路、区域空间尺度的研究、各种要素的组合及其城市群规划深层发展等问题,进行初步的探索。在城市群区总体发展的关键要素整合方面提出了三个新观点:①城市发展与自然要素的整合;②重视区域交通要素的组织;③城市群区内经济要素流的合理化。以期引起对此问题的深入研究与实践总结。姚士谋 陈彩虹 陈爽 William Y B Chang 2005长江流域资源与环境2005,14,3:13
5中国城市化发展速度界定的初步探索显示文摘纵观我国城市化发展历程,虽然取得了举世瞩目的成就,同时也带来了许多问题,具体表现为城市化快速扩张过程中带来的资源与生态环境压力。阐述了城市化发展的国内外背景,认为城市化过程中的土地资源、水资源、环境容量等是影响城镇健康可持续发展的重要因素,构成了制约城市发展的综合性支撑体系。对我国城市化道路健康发展的基本策略进行了阐述。在对我国城市化发展速度的主要影响因素进行分析的基础上,根据人均GDP增长和各地区城市发展条件与潜力,通过综合指标分析,对我国不同类型区的城市化发展速度进行了初步界定及趋势分析。吴建楠 姚士谋 朱天明 William Y B Chang 2010长江流域资源与环境2010,19,5:4
6新一代渴望导管: 在肺的栓塞的处理的可行性显示文摘 AIM: To report our preliminary experience with a new generation aspiration catheter in the treatment of symptomatic pulmonary embolism(PE). METHODS: A retrospective database search for pulmonary artery embolectomy since introduction of the Pronto.035' and XL extraction catheter(Vascular Solutions, Minneapolis, MN) at our institution in 10/2009 was performed. Ten consecutive patients were identified in which the Pronto.035' or XL catheter was used between 01/2010 and 03/2013. All patients were referred for catheter based embolectomy due to contraindications to systemic lysis, or for being in such a critical clinical condition that immediate percutaneous treatment deemed warranted. The computed tomography(CT) right to left heart ratio as predictor for the severity of the PE was retrospectively evaluated on standard axial views. The difference between pre- and post-procedure pulmonary pressure measures was taken to assess the procedural effect.RESULTS: Extensive PE was confirmed angiographically in all patients. Measured right- to left ventricle(RV/LV) ratios were elevated beyond one in seven of the eight available CTs. Acute procedural success defined as clinical removal of visible thrombus and improvement in mean pulmonary artery pressure was seen in all recorded patients(n = 8), the mean pulmonary pressures declined from a median(range) of 35.5(19-46) to 23(10-37, P = 0.008) mmHg. Neither death nor other complications occurred intra- or immediately periprocedural, yet short term mortality within 30 d was found in 6 out of 9 patients, one patient was lost in follow up. The cause of death within 30 d in the 6 patients was identified as: Circulatory failure in direct connection with the PE(n = 2), stroke, sepsis, or succumbing to malignancy in a hospice setting(n = 2). CONCLUSION: Success in thrombus removal with improved pulmonary hypertension and systemic hypotension suggests this aspiration technique to be effective. Aspiration catheters should be part of further trials.Wolf E Heberlein Mollie E Meek Omar Saleh James C Meek Shelly Y Lensing William C Culp 2013World Journal of Radiology2013,5,11:2
7Fulminant hepatic failure as the initial presentation of acute autoimmune hepatitis显示文摘William R Kessler Oscar W Cummings George Eckert Naga Chalasani Lawrence Lumeng Paul Y Kwo 2004Clinical Gastroenterology and Hepatology2004,,7:2
8Terahertz Semiconductor Quantum Well Devices显示文摘For eventually providing terahertz science with compact and convenient devices,terahertz (1~10THz) quantum-well photodetectors and quantum-cascade lasers are investigated.The design and projected detector performance are presented together with experimental results for several test devices,all working at photon energies below and around optical phonons.Background limited infrared performance (BLIP) operations are observed for all samples (three in total),designed for different wavelengths.BLIP temperatures of 17,13,and 12K are achieved for peak detection frequencies of 9.7THz(31μm),5.4THz(56μm),and 3.2THz(93μm),respectively.A set of THz quantum-cascade lasers with identical device parameters except for doping concentration is studied.The δ-doping density for each period varies from 3.2×1010 to 4.8×1010cm-2.We observe that the lasing threshold current density increases monotonically with doping concentration.Moreover,the measurements for devices with different cavity lengths provide evidence that the free carrier absorption causes the waveguide loss also to increase monotonically.Interestingly the observed maximum lasing temperature is best at a doping density of 3.6×1010cm-2.Liu H C Luo H Ban D Waichter M Song C Y Wasilewski Z R Buchanan M Aers G C SpringThorpe A J Cao J C Feng S L Williams B S Hu Q 2006Journal of Semiconductors2006,27,4:2
9Colonic motility abnormality in patients with irritable bowel syndrome exhibiting abdominal pain and diarrhea显示文摘William Y Chey Hai Ou Jin Mun Ho Lee Sung Wu Sun Kae Yol Lee 2001The American Journal of Gastroenterology2001,,5:2
10Chemical vapor deposition of Si nanowires nucleated by TiSi2 islands on Si显示文摘Kamins T I Stanley Williams R Chang Y L 2000Appl Phys Lett2000,76,5:2
11Strategies to tackle the challenges of external beam radiotherapy for liver tumors显示文摘Primary and metastatic liver cancer is an increasingly common and difficult to control disease entity.Radiation offers a non-invasive treatment alternative for these patients who often have few options and a poor prognosis.However,the anatomy and aggressiveness of liver cancer poses significant challenges such as accurate localization at simulation and treatment,management of motion and appropriate selection of dose regimen.This article aims to review the options available and provide information for the practical implementation and/or improvement of liver cancer radiation programs within the context of stereotactic body radiotherapy and image-guided radiotherapy guidelines.Specific patient inclusion and exclusion criteria are presented given the significant toxicity found in certain sub-populations treated with radiation.Indeed,certain sub-populations,such as those with tumor thrombosis or those with larger lesions treated with transarterial chemoembolization,have been shown to have significant improvements in outcome with the addition of radiation and merit special consideration.Implementing a liver radiation programrequires three primary challenges to be addressed:(1) immobilization and motion management;(2) localization;and(3) dose regimen and constraint selection.Strategies to deal with motion include simple internal target volume(ITV) expansions,non-gated ITV reduction strategies,breath hold methods,and surrogate marker methods to enable gating or tracking.Localization of the tumor and organs-at-risk are addressed using contrast infusion techniques to take advantage of different normal liver and cancer vascular anatomy,imaging modalities,and margin management.Finally,a dose response has been demonstrated and dose regimens appear to be converging.A more uniform approach to treatment in terms of technique,dose selection and patient selection will allow us to study liver radiation in larger and,hopefully,multicenter randomized studies.Michael I Lock Jonathan Klein Hans T Chung Joseph M Herman Edward Y Kim William Small Nina A Mayr Simon S Lo 2017World Journal of Hepatology2017,9,14:2
12An intragenie MEF2- dependent enhancer directs muscle-specific expression of microRNAs 1 and 133显示文摘Liu N Williams AH Kim Y 2007Proc Natl Acad Sci USA2007,104,20:1
13Maternai plasma concentrations of insulin-like growth factor-1 and insulin-like growth factor-binding protein-1 in early pregnancy and subsequent risk of preeclampsia显示文摘Ninq Y Williams MA Vadachkoria S 2004Clin Biochem2004,37,11:1
14Circulating IL-6 as a predictor of radiation pneumonitis 显示文摘Chen Y Rubin P Williams J 2001Int J adiat Oncol Biol Phys2001,49,3:1
15Rubber - thermoplastic compositions显示文摘Coran A Y Patel R P Williams D 1982Rubber Chem Technol1982,55,:1
16Small rat islets are superior to large islets in in vitro function and in transplantation outcomes 显示文摘MacGregor R R Williams S J Tong P Y 2006Am J Physiol Endocrinol Metab2006,290,5:1
17The anatomy of tissue cultured red raspberry prior to and after transfer to soil 显示文摘Danielle J D William E V Kwai Y L 1985Plant Cell: Tissue and Organ Culture1985,,1:1
18Effect of fermentable carbohydrates on piglet facial bacterial communities as revealed by denaturing gradient gel electrophoresis analysis of 16S ribosomal DNA显示文摘Konstantinov S R Zhu W Y Williams B A 2003FEMS Microbiology Ecology2003,43,:1
19Mechanism of improved aged rubber-to-brass adhesion using one-component resins显示文摘Pankaj Y Patil William J Van Ooij 2005Rubber Chemistry and Technology2005,78,1:1
20Self-assembled peptide nanoarrays:An approach to studying protein-protein interactions显示文摘Williams B A R Lund K Liu Y 0,,17:1
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