香兰素及其主要衍生物化学性质的CNDO/2研究

用CNDO/2法研究了香兰素,并对香兰素及其三个主要衍生物的化学性质作了理论分析。结果为合成香兰素系列香料提供了理论依据。     

1,3,5-苯三甲醛的合成与应用研究进展

介绍了1,3,5-苯三甲醛的合成与应用。在1,3,5-苯三甲醛的众多合成方法中,以氧化还原方法最常见,此外水解、聚合等方法各具优点,在满足高产率和绿色化学方面有了更多选择。1,3,5-苯三甲醛是一种具有广泛开发应用前景的化学合成中间体,以其为原料合成的大分子物质具有优异的化学、物理特性和生物活性,在催化、光电、抗病毒,以及分子吸附和药物包材等方面具有广泛的应用。     

Near-IR absorption transition of H4 to F2 for UCl6 complex in M2ZrCl6 host crystals (M = K, Rb, and Cs): an experimental and theoretical study

The near-IR electronic transition from ground-state Г₁ of ³H₄ to the excited-state Г₃ of ³F₂ for the UCl₆²⁻ complex in three M₂ZrCl₆ host crystals (M = K⁺, Rb⁺, and Cs⁺) has been investigated experimentally and theoretically. The vibration frequency of the excited state is found to be sensitive to the alkaline ion substitution and the frequency variation follows the trend predicted by the ‘counterion effect’. In contrast to previous studies, the apparent anomaly in the intensity ratio of the two vibronic peaks from the prediction of a Boltzmann distribution relationship is attributed to the vibration frequency difference between the ground and the excited state. This new interpretation is supported by computer simulation of the experimental optical spectra.     

Fluorinated carbon with ordered mesoporous structure

Fluorination and structural change of highly ordered mesoporous carbons were studied. Mesoporous and fluorinated carbons with ordered cubic structure were synthesized and characterized with TEM, FTIR, adsorption, and EDX.     

X光激光薄膜锗靶的制备

 介绍了X光激光薄膜锗靶的制备工艺，在厚度为90nm的formvar膜上，采用磁控溅射技术沉积30~60nm厚的锗膜。对锗膜的应力进行了初步的测试与分析，制得的薄膜经干涉仪测量符合要求。     

Modeling and stability analysis for a cholera model with vaccination

In this paper, we consider a cholera model with vaccination. The disease‐free equilibrium of the system is globally asymptotically stable when the basic reproduction number . If , the disease persists and the unique endemic equilibrium is globally asymptotically stable in the interior of the feasible region under some conditions, which is obtained by compound matrices and geometric approaches. We perform sensitivity analysis of on the parameters in order to determine their relative importance to disease transmission and prevalence. Numerical simulations are presented to illustrate the results. Copyright © 2011 John Wiley & Sons, Ltd.     

Ion-chromatographic trace analysis of mercury, cadmium and zinc by post-column derivatisation with a water-soluble porphyrin

Summary A post-column derivatisation system with mesotetra (4-sulfonatophenyl)-porphyrin (TPPS₄) and PAR as accelerating agent in a borate buffer pH 11.5 in the presence of tartrate and NaCl is proposed. The complexes of Cd, Zn and Hg have maximum absorption at 430 nm. The separation system consists of silica-gel chemically bonded cation exchanger as stationary phase and a tartrate-NaCl solution as mobile phase. The separation can be finished within 10 min. The calibration curves of these metal ions with the peak area of the chromatogram were found to be linear in the range of 0.002–0.8, 0.1–8.0 and 0.05–20.0 mg/l for Cd, Hg and Zn. The detection limits for Cd, Hg and Zn are 0.05, 5 and 1 ng. This new method was applied to the analysis of waste water, silicates and corn with satisfying results.

---

Ionen-chromatographische Spurenanalyse von Hg, Cd und Zn durch Nachsäulen-Derivatisierung mit einem wasserlöslichen Porphyrin

     

硼氢化反应机理(Ⅰ):HCN+BH_3反应的反应途径

利用量子化学从头计算法RHF／4-31G基组对氢氰酸的硼氢化反应进行了理论研究．IRC分析表明：氢氰酸与甲硼烷通过“类四中心”过渡态，直接加成生成产物．排除了另两种反应机理的可能性：（1）甲硼烷直接进攻碳-氮π键，经三中心过渡态生成产物；（2）首先形成直线型分子复合物，然后靠分子内氢迁移重排生成产物     

微波灭菌的研究进展

微波灭菌作为一种新型的灭菌方法,现已广泛应用于食品、医疗和高科技领域中。传统灭菌方法费时费力、污染大、灭菌效果一般,而微波灭菌的效率高、速度快,处理后无污染。主要介绍微波灭菌的机理、影响灭菌效果的因素以及该法的发展前景。