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A sensitive and efficient method for simultaneous determination of glutamic acid (Glu), gamma-amino-butyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) in rat endbrains was developed by high-performance liquid chromatography (HPLC) with fluorescence detection and on-line mass spectrometric identification following derivatization with 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC). Different parameters which influenced derivatization and separation were optimized. The complete separation of five neurotransmitter (NT) derivatives was performed on a reversed-phase Hypersil BDS-C-18 column with a gradient elution. The rapid structure identification of five neurotransmitter derivatives was carried out by on-line mass spectrometry with electrospray ionization (ESI) source in positive ion mode, and the BCEOC-labeled derivatives were characterized by easy-to-interpret mass spectra. Stability of derivatives, repeatability, precision and accuracy were evaluated and the results were excellent for efficient HPLC analysis. The quantitative linear range of five neurotransmitters were 2.441-2 x 10(4) nM, and limits of detection were in the range of 0.398-1.258 nM (S/N = 3:1). The changes of their concentrations in endbrains of three rat groups were also studied using this HPLC fluorescence detection method. The results indicated that exhausting exercise could obviously influence the concentrations of neurotransmitters in rat endbrains. The established method exhibited excellent validity, high sensitivity and convenience, and provided a new technique for simultaneous analysis of monoamine and amino acid neurotransmitters in rat brain. (C) 2008 Elsevier B.V. All rights reserved.

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根据应用对象的不同,结构光测量路径规划分为基于CAD模型的测量路径规划和无模型的测量路径规划。本文针对无模型的测量路径规划问题,提出了一种基于机器人特征点示教和准均匀B样条插值的半自动自由曲面测量路径规划策略。该策略充分考虑了自由曲面的特征及结构光测量路径的特殊要求,通过少量特征点的示教和准均匀B样条插值,半自动的规划出测量路径。实验证明,该规划策略能提高无模型工件测量的效率,且该策略已在智能测量建模加工一体化装备中得到了应用。

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本文给出了一种基于视觉的、造价低廉实用的非接触式机器人直线轨迹测量系统 .该测量系统由结构光视觉传感器、测量轨道、主控计算机及相关软件组成 .视觉传感器可固定于机器人末端 .当机器人末端带动视觉传感器沿测量轨道做直线运动时 ,通过传感器测量相对测量轨道的连续位姿关系 ,就可间接描述机器人末端的运动轨迹 .当重复同一直线运动时 ,可检测出机器人的轨迹重复性 .本文综述了机器人直线轨迹测量设备的研究现状 ,介绍了轨迹检测系统的测量原理 ,重点讨论了该测量系统的两个关键技术 :空间特征点的图象提取技术和三维坐标计算方法 ,并描述了该系统的结构、性能指标和测量试验结果 .

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本文简要说明了防汛与兴利调度指挥信息系统的意义、目的和任务;介绍了系统的基本组成、逻辑结构、信息流模型和数据通信网络结构;并论述了系统中有关综合通信网络、洪水预报及水库调度模型,信息集成和系统应用集成三个主要方面的关键技术问题及解决途径.

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构建了贵州20世纪80年代、90年代和21世纪初等3期历史石漠化数据,利用其空间变换和数学模型详细探讨和评价了石漠化的时空演变过程,研究发现:(1)研究时段内贵州省石漠化总面积变化不明显,但石漠化内部类型之间的相互演变非常显著,各类型之间的演变具有转移、多变、“此消彼长”的特点。(2)石漠化的时空演变过程可分为单变方式、层变方式、返变方式等3种基本类型,其中以层变方式为主,单变方式为辅,返变方式较少。(3)石漠化正向演变与逆向演变并存,治理速度赶不上恶化速度,两者的比值为82.29%,局部治理,整体恶化。(4)各石漠化类型总的演变速率是398.31km^2·a^-1,石漠化等级越高,演变速率越慢。(5)石漠化演变频率最快的是中度石漠化和潜在石漠化,轻度石漠化的演变频率明显低于中度石漠化。对石漠化的空间演变区域特征和影响因子做了宏观的定性分析、并根据石漠化演变特点对综合治理提出了相应的建议。

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海相侏罗系是羌塘盆地发育最全、分布最广泛的沉积层系。作者根据详细的野外地质工作,收集了典型剖面的岩相、沉积构造和大量的化石,并借鉴、总结前人的研究成果,对该区双壳类生物地层进行较系统的、全面的分析研究,划分了五个双壳类化石组合:Camptonectes auritus—Pteroperna costatula,Eomiodon angulatus-lsognomon(Mytiloperna)bathonica,Camptonectes laminatus-Anisocardia beaumonti,Anisocardia tenera—Modiala biparta以及Gervillella aviculoides—Radulopecten fibrosus;认为该区雁石坪群的时代从巴柔期至牛津-基末里期,从而建立起生物地层格架及年代地层格架。根据沉积标志以及典型的化石组合,探讨了研究区古地理环境,并识别出滨海、潮坪、溻湖、碳酸盐台地以及碳酸盐缓坡等古沉积环境,揭示了各时期自然地理状况,对探索东特提斯地区的构造演化和双壳类的生态演变都有重要的意义。

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采用流体包裹体研究和地质研究相结合的方法,研究了龙门山茂汶推覆体和彭灌推覆体内流体特征,讨论了盆山间流体的温度,盐度变化规律和流体可能的流动方向。研究表明推覆体内流体的均一温度为101.9-226℃,压力为13.5-18.0MPa,密度为0.91-1.14g/cm^3。从茂汶推覆体至彭灌推覆体,流体的盐度具有增高、温度总体有降低特征;靠近造山带一侧的盆地内流体,其盐度和温度明显低于造山带内推覆体中的流体。在推覆体内部,从推覆体前锋到主滑面流体的均一温度逐渐降低。断层是流体运移的主要通道,盆山间流体有运移和热交换,盆地流体有可能通过滑动面被带入造山带内部.

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