35 resultados para discovery services


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The Lhasa terrane, located between the Bangonghu-Nujiang suture zone and the Indus-Yalung Tsangpo suture zone in the southern Tibetan Plateau, was considered previously as a Precambrian continental block. Mesozoic and Cenozoic tectonic evolution of the Lhasa terrane is closely related to the subduction of the Tethys ocean and the collision between the Indian and European continents; so it is one of the keys to reveal the formation and evolution of the Tibetan plateau. The garnet two-pyroxene granulite which was found at the Nyingtri rock group of the southeastern Lhasa terrene consists of garnet, clinopyroxene, orthopyroxene, labradorite, Ti-rich amphibolite and biotite, with a chemical composition of mafic rock. The metamorphic conditions were estimated to be at T = 747 similar to 834 degrees C and P = 0.90 similar to 1.35GPa, suggesting a formation depth of 45km. The zircon U-Pb dating for the garnet amphibolite and marble associated with the granulite give a metamorphic age of 85 similar to 90Ma. This granulite-facies metamorphic event together with a contemporaneous magmatism demonstrated that the southern Lhasa terrane has undergone an Andean-type orogeny at Late Mesozoic time.

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A rapid and sensitive liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI-MS) assay for the determination of five pharmacologically active compounds (PAC) extracted from the traditional Chinese medicine, Rhodiola , namely salidroside, tyrosol, rhodionin, gallic acid, and ethyl gallate has been developed. In this method, PAC could be baseline separated and detected with DAD at 275 nm. The validation of the method, including sensitivity, linearity, repeatability, and recovery, was examined. The linear calibration curves were acquired with correlation coefficient >0.999 and the limits of detection LOD (at a signal-to-noise ratio=3:1) were between 0.058 and 1.500 mu mol/L. It was found, that the amounts of PAC varied with different species of Rhodiola . The established method is rapid and reproducible for the separation of five natural pharmacologically active compounds from extracts of Rhodiola with satisfactory results.

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A rapid capillary electrophoresis method for the separation of five natural pharmacologically active compounds from extracted Rhodiola, namely salidroside, tyrosol, rhodionin, gallic acid and ethyl gallate has been developed. The separation of five natural pharmacologically active compounds was carried out in a fused-silica capillary with 14 mM boric acid, 30 mM SDS and 2.5% acetonitrile, adjusted to pH 10.7 with NaOH. Applied potential was 21 kV. The temperature of the capillary was maintained at 25 degreesC by the instrument thermostating system, with the correlation coefficients of 0.9805-0.9989 for migration time, and relative standards of < 3.52% for peak areas. The established method is rapid and reproducible for the separation of five natural pharmacologically compounds from extracts of Rhodiola with satisfactory results.

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随着网络技术、特别是Internet技术的发展,分布式系统的高睦能、高可靠性、高灵敏度、可扩展性和系统透明性使得基于分布式系统的应用越来越广泛。在分布式坏境下,信息系统的集成是必须认真考虑的问题。研究如何集成和统一访问分布的、异构的数据资源,实现各种数据的转换、交流与共享;以及如何建立一个开放、可扩展和异构兼容的新一代信息管理系统成为当今网络应用的重要研究方向。本文针对建立月球探测数据管理和集成系统的数据集成与操作集成两方面的内容,重点分析和研究了数据存储管理和系统集成技术,结合月球探测数据管理的应用集成需求与特点提出了基于XML技术的数据存储与管理和基于Web Service技术的系统集成方案。并利用XML/WebService技术基于Net平台开发了一个月球探测数据管理与集成系统实例。研究内容主要包括以下四个方面: (1)基于XML的数据模型与数据库存储。利用XML的自描述性、独立于平台和应用、半结构化,机器可处理、可扩展性以及便于网络传输和广泛支持的特性,实现了基于关系数据库的XML数据存储。对系统中的结构化和非结构化数据信息、都进行了XML标记定义,实现了信息存储和查询的小粒度,增强了数据的表示、查询、插入和删除等数据处理能力和效率。同时,利用XML作为月球探测数据交换和信息传输的格式,也为实现与异构系统数据的互操作提供了理想的角军决方案。(2)基于WebServices的分布式信息系统集成的体系结构。在对XML、SOAP、WSDL和UDDI关键技术和标准规范进行研究与探讨基础上,针对绕月探测数据管理的需求提出了基于XML/Web Service的三层分布式结构模型。分别是表示层、应用逻辑层、服务端数据层。实现了系统功能的可迁移性和可装配性、各层间传输过程中数据流的XML化、接口定义的动态性。与传统技术开发的耦合的分布式应用系统相比,系统在跨平台性、可配置性、可伸缩性、可维护性等方面都有了大幅度的提高。(3)基于,NET平台系统的开发与实现。深入分析和研究了Mic1’osoft.NET平台的核心技术与整体技术框架,在VisLla1Sttldio.NET开发环境中利用C#、ASP.NET、ADO.NET基于关系型数据库Oracle9i开发实现了统一身份认证系统和月球探测数据管理与集成系统。统一身份认证系统是一个通用的统一用户身份认证管理系统,包括用户管理、身份验证、实体管理、日志监控和消息、管理等功能,达到了一次登录,所有系统共用的目的。月球探测数据管理与集成系统包括数据管理、信息发布、系统管理、综合查询和应用集成五大功能模块,相对于原来的紧祸合的应用系统而言,系统的开发效率、重用性、祸合度、灵活性和自适 应性都有了很大的提高。(4)基于XML/WebServices的动态系统集成。分析了传统分布式对象模型在异构环境集成的弊端,基于XML、SOAP和WSDL等技术规范基础上,实现了统一身份认证系统、月球探测数据管理与集成系统、小空间碎片数据库系统以及其它语言开发的应用系统的信息集成、实现了资源时空的有效整合。通过这些集成应用实例,充分体现和说明了Web Services技术在应用系统集成方面的优越性。本研究的成果,也将为地球化学研究领域涉及海量数据的处理、管理和系统集成提供示范实例,推动地球化学数据的融合和综合应用。