220 resultados para 02241830 CTD-100


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采用热失重分析法考察了端羟基环氧乙烷/四氢呋喃共聚醚及其与N-100固化后的聚醚聚脲聚氨酯胶片的热分解性能.讨论了增塑剂(邻苯二甲酸二丁酯、硝化甘油和1,2,4-丁三醇三硝酸酯混合物)、固体填料(铝粉、高氨酸铵和奥克托今)以及助剂(碳黑、硝化纤维素和健合剂)对聚醚聚脲聚氨酯胶片热分解性能的影响.结果表明共聚醚在惰性环境中于200℃左右开始分解.抗氧剂(2,6-二叔丁基-4-甲基酚)能有效提高共聚醚的分解稳定性;含增塑剂、固体填料和助剂的聚氨酯胶片的热分解性能以及抗氧剂的稳定效果因增塑剂、填料和助剂的不同而有较大差别.

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在对N-100结构进行分析和表征的基础上,描述了N-100的形成过程.通过建立结构模型.以高分辨核磁共振波谱(1H及定量(13)CNMR)为定量依据,计算了异氰酸酯百分含量、平均官能度和平均相对分子质量.讨论了影响定量准确性的两个因素.对其中来自NMR技术方面的主要因素──纵向弛豫时间做了对比.计算结果与实际测试值的一致性说明了结构模型是可行的.

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该综合器(5610A型)作为多核实验的发射源能输出2~3Vpp,0.1~160MHz不同频率的信号。频率变化由计算机控制。常见故障是无输出,或输出幅度小、使谱仪不能正常工作。上述故障多数与压控振荡器(VCO)控制电压不正常有关(它决定

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本文研究了铽(Tb~(3-))对钐(Sm~(3-))-2-噻吩甲酰三氟丙酮(TTA)-氯代甲基三烷基铵(N_(263))-Triton X-100荧光体系的共发光效应,结果表明:Tb~(3-)的浓度1×10~(-5)~5×10~(-5)mol/L范围内体系的荧光强度最大.Sm~(3-)的浓度在1.0×10~(-9)~1.0×10~(-7)mol/L范围内与荧光强度呈线性关系,检测限为1.0X10~(-11)mol/L,方法灵敏,简便,用于混合稀土样品中痕量Sm~(3-)的测定,结果满意。

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本文研究了稀土离子对铕(Eu)-2-噻吩甲酰三氟丙酮(TTA)-氯化甲基三烷基铵(N263)-Triton X-100体系的共发光能力,提出用放大倍数作为共发光能力比较的定量标准,用能量转移效率和能量利用率来预测稀土离子的共发光能力。该方法适用于不同条件或不同体系之间共发光能力的定量比较。

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本文研究了TritonX-100在浊点条件下对钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯(5-Cl-PADAB)络合物的析相条件,在pH4.0~6.0介质中,将胶束溶液加热到92±1℃,保持40min,络合物即被TritonX-100相富集。富集液在575nm测定吸光度,钴含量在0~4μg/5ml范围内服从比尔定律,干扰离子可在TritonX-100析相液中加入H_2SO_4消除。拟定的方法灵敏、简捷,已用于不经分离直接测定人发及自来水中痕量钴。

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本文研究了铽(Tb)、钇(Y)、钆(Gd)及它们的混合物对铕(Eu)-噻吩甲酰三氟丙酮(TTA)-氯化甲基三烷基铵(N_(263))-Triton X-100体系的共发光效应,发现稀土离子混合物的共发光效应具有线性加和性,用混合共发光体系不仅能保持单个稀土离子的共发光体系的增敏性,而且抗干扰能力增强,并经过实际样品分析的验证,结果令人满意。

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具有f-f超灵敏跃迁的稀土配合物导数吸收光谱可大幅度提高稀土元素的测定灵敏度,钕-高铁试剂(Ferron,7碘-8羟基喹啉-5-磺酸)即为此类配合物,但其测定灵敏度提高不多。研究发现,在Ln~(3+)(Pr~(3+)、Nd~(3+)、Er~(3+))-Ferron体系中加入表面活性剂可形成新的配合物,使其f-f超灵敏跃迁吸收谱线增强,峰形显著变化,其中钕和铒的吸收峰

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The transfer behavior of alkali motal ions K~+ and Na~+ across the interfaces of water/nitrobenzene and water/1, 2-dichloroethane facilitated by Triton X-100 is investigated by cyclic voltammetry with four electrodes. The equations of interfacial half-wave potential derived in terms of the mechanism proposed isverified by the experimental data and consistent with the practical △_0~wφ_p-pM curves.

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本文用四电极循环伏安法研究了非离子型表面活性剂Triton X-100推动碱金属离子K~+,Na~+等在水/硝基苯,水/1,2-二氯乙烷界面上的转移过程,根据实验结果提出Triton X-100推动金属离子转移的一种机制,推导了转移半波电位方程式,并用实验进行了验证。

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In this paper, the reactions of nitrone, N-methyl nitrone, N-phenyl nitrone and their hydroxylamine tautomers (vinyl-hydroxylamine, N-methyl-vinyl-hydroxylamine and N-phenyl-vinyl-hydroxylamine) on the reconstructed C(100)-2 x 1 surface have been investigated using hybrid density functional theory (B3LYP), Moller-Plesset second-order perturbation (MP2) and multi-configuration complete-active-space self-consistent-field (CASSCF) methods. The calculations showed that all the nitrones can react with the surface "dimer" via facile 1.3-dipolar cycloaddition with small activation barriers (less than 12.0 kJ/mol at B3LYP/6-31g(d) level). The [2+2] cycloaddition of hydroxylamine tautomers on the C(100) surface follows a diradical mechanism. Hydroxylamine tautomers first form diradical intermediates with the reconstructed C(I 00)-2 x I surface by overcoming a large activation barrier of 50-60 kJ/mol (B3LYP), then generate [2+2] cycloaddition products via diradical transition states with negligible activation barriers. The surface reactions result in hydroxyl or amino-terminated diamond surfaces, which offers new opportunity for further modifications. (C) 2007 Elsevier B.V. All rights reserved.

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The reaction of nitrone, N-methyl nitrone, and their hydroxylamine tautomers (vinyl-hydroxylamine and N-methyl vinyl-hydroxylamine) on the reconstructed Si(100)-2 x 1 surface has been investigated by means of hybrid density functional theory (B3LYP) and Moller-Plesset second-order perturbation (MP2) methods. The calculations predicted that both of the nitrones should react with the surface dimer via facile concerted 1,3-dipolar cycloaddition leading to 5-member-ring compounds. The reaction of hydroxylamine tautomers on the Si(100) surface follows pi-complex (intermediate) mechanism. For the reaction of N-methyl vinyl-hydroxylamine, the pi-complex intermediate undergoes [2+2] cycloaddition leading to a 4-member-ring compound. But in the reaction of vinyl-hydroxylamine, the intermediate undergoes H-migration reaction ("ene" reaction) resulting in the oxime-terminated Si surface. All the surface reactions result in the hydroxyl-terminated silicon surfaces, which are very useful for the further modification of the semiconductor.

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根据岩石矿物学研究,包括岩石结构、橄榄石的Fa值和低钙辉石的Fs值以及金属模式含量等,100块格罗夫山陨石分别被划分为:4块H3型、11块H4型(其中一块为H4-an)、10块H5型、3块H6型、2块L3型、6块L4型、31块15型、32块L6型和1块LL4型。格罗夫山普通球粒陨石在类型分布上,其比例和南极以及非南极普通球粒陨石有显著不同,说明可能存在相当数量的成对陨石。分类陨石样品比较新鲜,其中98块陨石的风化程度为W1,仅有2块陨石风化程度分别为W2和W3。另外,这些陨石中冲击程度较高的样品占有一定比例,它们是研究冲击作用的理想样品。