15 resultados para Kahn, Ida

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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The title complexes were synthesized and the crystal structures of their salts were determined by single-crystal X-ray structure analyses. Na-2[Zn-I(ida)(2)]. 7H(2)O: Triclinic, P1, a=0.523 4(2) nm, b=0.897 10(10) nm, c=1.069 10(10) nm, alpha=85.910(10)degrees, beta= 76.380(10)degrees, gamma=83.52(2)degrees, V=0.484 2(2) nm(3), Z=1. The complex anion [Zn-I (ida)(2)](2-) has a pseudo-octahedral structure in which the two N atoms: are in a trans configuration. Na-4[Hg-I(nta)(2)]. 7H(2)O: Monoclinic, C-c, a = 1.795 0(4) nm, b = 0.892 9(2)nm, c = 1.575 4(2) nm, beta = 92.78 (3)degrees, V = 2.526 2(9) nm(3), Z = 4. The complex anion [Hg-I (nta)(2)](4-) has a pseudo-bicapped-octahedral structure in which the two N atoms are in a trans configuration.

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金属离子ZnⅡ和HgⅡ分别是生物体必需的微量元素和对人体有害的毒性金属.如何有效地摄取ZnⅡ和排除HgⅡ一直是化学家感兴趣的研究课题.而ZnⅡ和HgⅡ能与各种氨基酸形成配合物,由于它们处于同一族,电子结构都是d10,故其配位结构只取决于金属离子半径的…

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氨基多羧酸类配合物的配位数和结构不但与金属离子的半径、电荷和电子结构有关,而且还与氨基多羧酸类配体的形状和大小有关。本文报道了Na2[FeⅢ(ida)2]2·3H2O(ida=亚氨基二乙酸根)配合物的合成并测定了它的分子结构和晶体结构。具体结果如下:单斜晶系,P21/c空间群,a=15.6480(10),b=16.7870(10),c=10.347(2),β=90.790(10)°,V=2717.7(6)3,单位晶胞中的分子数为3,对于4789个独立的衍射点,它的R值为0.0333。其中两个配合物离子[FeⅢ(ida)2]-都是N和N顺位的变形八面体结构。由此可知具有对称电子结构(high-spind5)的FeⅢ与被看成是edta(=乙二胺四乙酸根)去掉了CH2-CH2的双ida配体形成的配合物只能选择六配位八面体结构。

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The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data areas follows; Monoclinic, P2(1)/c, a=15.6480(10)Angstrom, b=16.7870(10)Angstrom, c=10.347(2)Angstrom, beta=90.790(10), V=2717.7(6)Angstrom(3), Z=3, and R=0.0333 for 4789 unique reflections. The complex anion has a pseudo-octahedral structure distorted more than the Cr-III and Co-III analogs, in which each, iminodiacetato ligand (ida(2-)) is coordinated in a facial fashion with the two N atoms in a cis configuration, resulting in an unsym-fac structure.

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Peptide mass mapping analysis, utilizing a regenerable enzyme microreactor with metal-ion chelated adsorption of enzyme, combined with matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) was developed. Different procedures from the conventional approaches were adopted to immobilize the chelator onto the silica supports, that is, the metal chelating agent of iminodiacetic acid (IDA) was reacted with glycidoxypropyltrimethoxysilane (GLYMO) before its immobilization onto the inner wall of the fused-silica capillary pretreated with NH4HF2. The metal ion of copper and subsequently enzyme was specifically adsorbed onto the surface to form the immobilized enzyme capillary microreactor, which was combined with MALDI-TOF-MS to apply for the mass mapping analysis of nL amounts of protein samples. The results revealed that the peptide mapping could routinely be generated from 0.5 pmol protein sample in 15 min at 50degreesC, even 20 fmol cytochrome c could be well digested and detected.

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用户界面是交互式软件系统中重要组成部分。它在应用软件中平均占开发量 和运行时间的40%~50%[Myers 1989]。界面设计工具可以用可视化的方法支持用 户界面的快速设计、减少手动开发工作量来提高系统的开发效率。同时还能够根 据用户定制系统,满足了不同用户的个性化需求。图形用户界面是最广泛应用的 用户界面,针对图形用户界面的设计已有Visual Studio,Qt Designer等成熟的设计 工具。使用软件界面设计工具能够将软件的用户界面部分和应用逻辑部分分离, 使设计人员更专注于软件界面的交互方式和现实效果,而开发人员则更专注软件 的应用逻辑实现。使用设计工具开发还能够根据用户变化改变设计来满足用户多 种多样的需求。 场景的概念最初是由Kahn[Kahn 1962]提出的,之后由Carroll领导的团队提出 了基于场景设计的一般框架[Rosson 2001]。场景设计方法在描述用户使用软件的 交互行为和系统反馈上面有着很强的能力[Go 2004]。然而,以往基于场景的设计 方法都使用文字来描述场景,缺少相应用户界面设计工具的支持。 本文通过研究分析基于场景设计方法,设计并实现了支持场景设计方法的界 面设计工具。该工具将软件界面场景以图形形式展示给设计人员,辅助用户对软 件界面需求进行发掘,帮助设计人员开展界面设计。本文的主要工作有: 1、以基于场景方法为指导确立了以图形化形式对场景进行描述的基本流程。 通过对已有界面设计工具进行分析得出软件界面设计的一般过程,并研究分析了 基于场景设计方法在软件界面设计中的使用及其优势。 2、在概要设计角度介绍了场景树、状态迁移图和界面布局可视化描述方式对 场景方法的支持。并详细介绍了界面设计工具的整体架构,重点阐述了各个模块 间的不同功能及在界面设计过程所起的作用。 3、详细分析了设计工具生成软件界面文档的描述规范。针对基于场景设计的 各个阶段阐述了与之对应的软件界面设计步骤。最后简单介绍了使用生成的文档 来开发与应用逻辑相关代码的过程。 4、以个人信息管理系统作为应用实例介绍整个界面软件的设计过程。并在此 基础上介绍了几个使用设计工具进行设计的实际系统,最后对设计工具未来的应 用和改进进行了展望。

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电子反常供需型Diels-Alder反应(inverse electron demabd Diels-Alder reaction,IDA)因其在天然生物碱及类似物合成中的应用,在近20年来已经逐渐引起关注[1].含氮芳杂环体系1,2,4-三嗪由于其特有的缺电子特征,作为双烯体非常适于进行这类反应[2].本文利用IDA反应从3-吡啶基-5,6-二取代-1,2,4-三嗪出发,设计出一条简捷、低成本的合成路线,成功地合成出不对称取代的2,3′-联吡啶和2,4′-联吡啶.这一类化合物已被应用于药物中间体或有机配体.

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Cyclic voltammetry of Vitamin K-3 (V-K3) was measured with Pt disk electrode, platinum interdigitated array (Pt-IDA) and Au-IDA microelectrodes in single and dual modes. The effects of pH, scan rate and collector potential on the current of generator and collector were studied. The collection efficiency of V-K3 at IDA electrodes was measured. The linear ranges for current response as a function of V-K3 concentration were found to he 10 mu M-1 mM (i(g)) and 1 mu M - 1 mM (i(c)) for the generator and collector of the Pt-IDA electrode, respectively. The effects of waiting time, potential difference and pulse electrolysis time in differential pulse voltammetry (DPV) on the peak current of V-K3 were studied to get the optimal condition at 0.1 M Na2HPO4, pH 11.50 and 11.0 for Au-IDA and Pt-IDA, respectively.

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An iminodiacetic acid (IDA)-type adsorbent is prepared at the one end of a capillary by covalently bonding IDA to the monolithic rods of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate). Cu(II) is later introduced to the support via the interaction with IDA. By this means, polymer monolithic immobilized metal affinity chromatography (IMAC) materials are prepared. With such a column, IMAC for on-line concentration and capillary electrophoresis (CE) for the subsequent analysis are hyphenated for the analysis of peptides and proteins. The reproducibility of such a column has been proved good with relative standard deviations (RSDs) of dead time of less than 5% for injection-to-injection and 12% for column-to-column (n = 3). Through application on the analysis of standard peptides and real protein samples, such a technique has shown promising in proteome study.

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The extract of Adinandra nitida leaves, named as Shiyacha in China, was studied by high performance liquid chromatography (HPLC)-ultraviolet detection-electrospray ionisation (ESI) tandem mass spectrometry (MS). Under the optimized condition, the analysis could be finished in 45 min on a Hypersil C18 column combined with negative ion detection using information-dependent acquisition (IDA) mode of a Q TRAP (TM) instrument. Six flavonoids were identified as epicatechin, rhoifolin, apigenin, quercitrin, camellianin A, and camellianin B among which rhoifolin was for the first time found in Shiyacha. And the fragment pathways of these flavonoids were elucidated. Furthermore, with epicatechin, rhoifolin, and apigenin as markers, the quality control method for Shiyacha and its relevant product was firstly established. Calibration linearity was good (R-2 > 0.9992) over a three to four orders of magnitude concentration range with an S/N = 3 detection limit of 2.5 ng. (c) 2004 Elsevier B.V. All rights reserved.

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Direct-injection electrospray ionization mass spectrometry in combination with information-dependent data acquisition (IDA), using a triple-quadrupole/linear ion trap combination, allows high-throughput qualitative analysis of complex phospholipid species from child whole blood. In the IDA experiments, scans to detect specific head groups (precursor ion or neutral loss scans) were used as survey scans to detect phospholipid classes. An enhanced resolution scan was then used to confirm the mass assignments, and the enhanced product ion scan was implemented as a dependent scan to determine the composition of each phospholipid class. These survey and dependent scans were performed sequentially and repeated for the entire duration of analysis, thus providing the maximum information from a single injection. In this way, 50 different phospholipids belonging to the phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, phosphatidylcholine and sphingomyelin classes were identified in child whole blood. Copyright (C) 2005 John Wiley & Sons, Ltd.