化学蒸气沉积硅氧化合物调变HZSM－5沸石的研究

本文研究了正硅酸乙酯分别在无胺法和有胺法制得的ＨＺＳＭ－５沸石上的沉积过程，并用吸附，ＮＨ３－ＴＰＤ及异丙醇探针反应等手段表征了沉积后的样品，发现沉积仅在外表面上进行，可使孔口变小但不影响孔道内性质，显示有对于二甲苯分子的择形吸附能力，且在甲苯甲醇烷基化反应和二甲苯异构化反应中表现出良好的择形催化性能．     

红厚壳属植物化学成份及药理活性研究进展

综述了近年来对红厚壳属植物中的化学成分及药理活性研究，重点讨论了18种 红厚壳属植物中Zhao吨酮类，香豆素类，黄酮类和萜类的化学成分，并讨论了它们 的药理活性。     

清除树脂在组合化学中的应用

清除树脂是一种特殊的固相试剂。近五年，它们被广泛的用于平行液相法合成组合化学库，简化液相组合化学库的纯化操作。本文综述了清除树脂在纯化操作中的使用策略。根据清除纯化原理，介绍了共价键型和离子键型两类清除树脂。给出了清除树脂在组合化学中的具体应用实例。最后对清除树脂的发展作了展望。     

氧化铬着色的随角异色颜料的制备与性能研究

采用具有干涉色的云母钛作为基质材料,以氧化铬膜着色,制备了随角异色功能颜料。用XRD、X-RiteMA86Ⅱ5角度分光光度计对产物进行测试分析,研究了不同的基质材料对颜料随角异色效果的影响,分析比较了黑白两种不同背底对颜料的明度和变化效果的影响。结果表明,改变基质材料的干涉色可以制得不同变色效果的随角异色颜料,颜料在黑色背底上的明度值变化范围较大,颜料的变色效果比较明显。     

微流控层流技术的研究

基于微型通道自身的层流特点而发展起来的多相层流技术,从最初的液-液微萃取开始,由于其结构加工简单、操作方便和分析功能强大,已逐渐发展成为一种加工分析方法,为微流控分析的研究应用打开了一个崭新的局面。本文概述了层流的基本原理,总结了近10年来在这方面的研究,包括层流界面间的分子扩散、转移现象和化学反应,以及层流刻蚀加工技术及其在制备纳米材料和在生命医学方面的应用。具体介绍了应用层流技术进行微芯片的加工制作,微型反应器的制备,离子、分子的分离分析,聚合物薄膜的形成和应用,微通道内有机合成反应的控制,溶液的浓度梯度控制以及在免疫检测中的应用,对细胞、生物大分子的操作控制,以及对生物试剂的预处理分析等。     

Chemical preparation and investigation of Fe-P-B ultrafine amorphous alloy particles

A series of Fe-P-B ultrafine amorphous alloy particles has been prepared by the chemical reduction method The composition and size of the particles have been effectively adjusted.Mossbauer spectroscopy in addition to sonic other techniques has been used to investigate the reaction process,the factors that influence the preparation,the crystallization of the particles,and the interactions between the components within them.The results indicate that the co-deposition of iron,phosphorus and boron atoms in the solution at room temperature forms Fe-P-B amorphous alloy particles,and a preferential bonding of Fe-P bond to Fe-B one exists in the particles.     

萜类化合物13C NMR化学位移的定量构谱相关研究

利用原子电性作用矢量(Atomic electro-negativity interaction vector,AEIV)和原子杂化状态指数(Atomic hybridization state index,AHSI)对萜类化合物中的C原子进行结构表征并与其核磁共振碳谱(13C NMR)建立了优良的定量构谱相关(QSSR)模型.其中29个单萜类化合物中的290个C原子建模的计算值经留一法(Leave-one-out,LOO)交互校验(Cross-validation,CV)预测值的复相关系数(R)分别为0.9900和0.9867,进一步使用倍半萜、二萜、三萜化合物分子中65个C原子的13C NMR化学位移值来检测该模型的稳定性,模型预测值和观测值间复相关系数(R)为0.9777,取得了令人满意的结果.     

Rapid and sensitive liquid chromatography-tandem mass spectrometry for the quantitation of epirubicin and identification of metabolites in biological samples

A highly sensitive and selective liquid chromatography-mass spectrometry (LC-MS) method has been developed for the determination of epirubicin in serum and cell specimens using daunorubicin as an internal standard. Using atmospheric pressure chemical ionisation (APCI), the epirubicin metabolites were readily distinguishable by their fragmentation pattern in the mass spectrometer. Selected reaction monitoring (SRM) mode was employed for quantitation of epirubicin and the metabolites. Following extraction, chromatography was performed on a C18 column with a mobile phase consisting of water-acetonitrile-formic acid, pH 3.2, with a flow rate of 200 μl/min. The limit of detection (LOD) and the limit of quantitation (LOQ) of this method in serum were determined to be 1.0 and 2.5 ng/ml, respectively. Linearity of the method was verified over the concentration range of 2.5-2000 ng/ml, with a high correlation coefficient (R² ≥ 0.998). For the extraction procedure, an aliquot of 500 μl serum, spiked with internal standard, was extracted using a chloroform-2-isopropanol (2:1, v/v) mixture. The method has been applied to the analysis of epirubicin in cancer cell samples and the identification of known and unknown metabolites in clinical trial patient serum samples.     

Chemical modification of L-asparaginase with N, O-carboxymethyl chitosan and its effects on plasma half-life and other properties

E.coli L-asparaginase,an antitumor enzyme,was chemically modified with N,O-carboxymethyl chitosan to lower its artigenicity and increase its plasma half-life.The results showed that the modified L-asparaginase has almost the same apparent Km value as that of native enzyme.The modified L-asparaginase also showed a higher protease stability against trypsin and a-chymotrypsin.After being modified,the enzyme exhibited the complete loss of antigenicity towards antiasparaginase serum.In addition,the higher the molecular weight of modifying reagents,the better the effects on reduction of antigenicity.When tested in vivo,the plasma half-life of the modified enzyme (t1/2=40 h) was over 33 times longer than that of the native enzyme (t1/2=1.2 h).     

A new method for determination of uric acid by the lactic acid-acetone-BrO(3)(-)-Mn(2+)-H(2)SO(4) oscillating reaction using the analyte pulse perturbation technique

A new analytical method for the determination of uric acid (UA) by the perturbation of UA on the Belousov-Zhabotinsky oscillating reaction is proposed. The method is based on the linear relationship between the changes in the oscillating period and the concentration of UA. The calibration curve is linear over the range of 2.0 × 10⁻⁵ to 5.0 × 10⁻⁴ M, with a detecting limit of 3.28 × 10⁻⁶ M. The method features good precision (R.S.D.: 3.59%) and excellent throughput (10 samples h⁻¹). The possible mechanism of the perturbation of UA on the oscillating reaction is discussed.