吸附在活性炭上的二氧六环类固相和类液相性质的NMR研究

物理吸附在活性炭上的有机分子的性质,一直是人们感兴趣的问题。近年来,人们开始用NMR梯度场和核弛豫的方法,研究活性炭上吸附分子的扩散运动和分子交换运动.由于吸附分子在活性炭上处于不同的状态,其核弛豫表现出快、慢两个过程。通过拟合磁化矢量随时间变化的曲线,可以得到不同状态分子的百分含量。本文采用核弛豫的方法,研究活性炭的表面酸性基团及孔径对被吸附的二氧六环(DO)类固相和类液相形成的影响.并对不同吸附量下,DO在活性炭上的吸附行为进行讨论。     

Fast and accurate Coulomb calculation with Gaussian functions

Coulomb interaction is one of the major time-consuming components in a density functional theory (DFT) calculation. In the last decade, dramatic progresses have been made to improve the efficiency of Coulomb calculation, including continuous fast multipole method (CFMM) and J-engine method, all developed first inside Q-Chem. The most recent development is the advent of Fourier transform Coulomb method developed by Fusti-Molnar and Pulay, and an improved version of the method has been recently implemented in Q-Chem. It replaces the least efficient part of the previous Coulomb methods with an accurate numerical integration scheme that scales in O(N2) instead of O(N4) with the basis size. The result is a much smaller slope in the linear scaling with respect to the molecular size and we will demonstrate through a series of benchmark calculations that it speeds up the calculation of Coulomb energy by several folds over the efficient existing code, i.e., the combination of CFMM and J-engine, without loss of accuracy. Furthermore, we will show that it is complementary to the latter and together the three methods offer the best performance for Coulomb part of DFT calculations, making the DFT calculations affordable for very large systems involving thousands of basis functions.     

Spectroelectrochemical investigation of direct electron transfer between resting horseradish peroxidase and its oxidation states promoted by DNA

Direct electron transfer between resting horseradish peroxidase (HRP) and its oxidation states was observed at a gold mesh electrode in a spectroelectrochemical cell in the presence of DNA. The conversion between HRP and the oxidized species induced electrochemically was found to be reversible and parallel to that initiated chemically. DNA played an important role as electron carrier and promoted the electron transfer between HRP and the electrodes. Voltammetric results and CD spectra indicated an interaction between HRP and DNA. Moreover, the secondary structure of HRP was slightly disturbed upon mixing with DNA. The direct spectroelectrochemistry of HRP at a gold mesh electrode presented new information on its bioelectrochemical characteristics.     

熔融碳酸盐燃料电池研究

以烧结Ｎｉ作电极，以ＬｉＡｌＯ２无机膜作电池隔膜，组装成了电极而积２８ｃｍ＾２的小型熔融碳酸盐燃料电池，试验了各种工作条件对电池性能的影响，电池经多次启动性能无衰减，放电电流密度１００ｍＡ／ｃｍ＾２，电池电压０．９５Ｖ，放电电流密度１２５ｍＡ／ｃｍ＾２，电池输出功率１１４ｍＷ／ｃｍ＾２，燃料气利用率８０％，电池能量效率３１％。     

Kinetics and mechanism of the exothermic first-stage decomposition reaction for 1-nitro-3-(β,β,β-trinitroethyl)-2-imidazolidinone

Under linear temperature increase condition the thermal behavior, mechanism and kinetic parameters of the exothermic first-stage decomposition reaction of the title compound have been studied by means of DSC, TG, DTA, IR and mass spectrometry. The mechanism of above-mentioned reaction could be expressed by the following scheme. The apparent activation energy, pre-exponential constant and reaction order of this reaction are 112 kJ/mol, 10^9.62sec^–1 and 0 respectively.

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Zusammenfassung Bei linearem Temperaturanstieg wurde mittels DSC, TG, DTA IR und Massenspektrometrie das thermische Verhalten, der Mechanismus und die kinetischen Parameter der exothermen first-stage Zersetzungsreaktion der Titelverbindung untersucht. Der Mechanismus der obengenannten Reaktion kann mit folgendem Reaktionsschema veranschaulicht werden: Die scheinbare Aktivierungsenergie, der präexponentielle Faktor und die Reaktionsordnung dieser Reaktion betragen 112 kJ/mol, 10^9.62 s^–1 bzw. 0.

     

镍纳米线电极对乙醇的电催化氧化动力学参数的测定

循环伏安实验表明,以多孔氧化铝膜为模板制备出的镍纳米线电极对乙醇的电化学催化氧化具有很高的催化活性.用强制对流流体动力学的方法求算出乙醇在镍纳米线电极上的电子传递过程的速率常数高于许多文献报导值,而电子传递过程的随后步骤的速率常数相近.     

糖尿病人微量元素谱的多元分析

胜多元分析了糖尿病患者样品中微量元素，了解微量元素与糖尿病的关系，并提出了新见解。用ＩＣＰ－ＡＥＳ测定糖尿病患者血、发中１８种微量和宏量元素 ；结果经多元分析处理，找到血、发共有的相关链：Ｍｎ－Ｎｉ－Ｃｕ－ＳｒＴｉ，它与患者年龄、性别、样品无关，看来它提供了机体的特殊信息。     

高灵敏度电容型透明质酸结合蛋白免疫传感器的研制

实验用金电极自组装技术构建透明质酸结合蛋白电容型免疫传感器，采用交流阻抗技术对电极表面生物绝缘膜进行研究。按R(RC)等效电路图对其阻抗谱进行拟合的偏差较小，显示实际体系接近于拟合的电路图。该传感器对1-100mg/L抗原具有良好的线性响应。构建的生物膜对于一定范围的离子强度、酸度具有良好的稳定性，表明其有望应用于临床检测。     

8—氮杂腺嘌呤的极谱伏安行为

以多种电化学方法研究了８－氮杂腺嘌呤的极谱伏安行为在ＨＡｃ－ＮａＡｃ缓冲溶液中的极谱伏安行为，它产生了两个良好稳定的线性扫描伏０发峰，峰电位分别为－１．０８Ｖ和－１．３４Ｖ，实验表明，Ｐ１具有弱吸附性质，Ｐ２具有催化氢波性质，Ｐ１峰高和８－ＡＡ浓度在１×１０＾－８－８×１０－＾４ｍｏｌ／Ｌ范围内呈良好的线性关系。