草酸锰分解过程的机理函数判别和动力学研究

用等温热重和线性升温热重分析法研究了草酸锰热分解过程,提出了判断其机理函数的3步判别法。经实验和理论分析证明,该反应受随机成核和晶核随后生长的过程(A_3a机理)支配,其活化能E=103.95 kJ/mol,频率因子A=4.448×10~8min~(-1).动力学补偿效应为IgA=0.09661E-1.2856     

四（对羟基苯基）卟啉—硅胶固定相的合成及在核苷酸分析中的应用

以大孔微硅胶作基体，经γ－氨丙基三乙氧基硅烷活化与间隔臂氯代环内烷反应后，再与预先合成的四（对羟基苯基）卟啉配体键合，构成电荷转移型亲和色谱固定相。以ＰＨ＝７．０的磷酸盐缓冲溶液作流动相，成功实现对一些核苷酸的高效液相亲和色谱分离。     

The analysis of salen complexes by fast atom bombardment mass spectrometry and atmospheric pressure chemical ionization mass spectrometry

Fast atom bombardment (FAB) mass spectrometry provides useful structural information about salen complexes and salen-based oxo transfer catalysts that are not appreciably soluble in organic solvents. It was discovered that initial dissolution of these complexes in trifluoroacetic acid was crucial for producing good FAB mass spectra. Trifluoroacetic acid helps dissolve the salen-based catalysts, concentrates the analyte molecules at the matrix surface, and most importantly, suppresses the reduction process, which is a well-known phenomenon when protic matrices are used. The best FAB matrices for these catalysts were found to be thioglycerol and “magic bullet.” However, dechlorination occurred under the acid conditions for complexes containing iron chloride and manganese chloride. Demetalation also occurred for nickel-containing oxo transfer salen-based complexes. When the salen-based complexes are soluble in LC solvents, they can be analyzed easily by atmospheric pressure chemical ionization (APCI) mass spectrometry without the employment of relatively nonvolatile matrices. In addition, APCI/MS provides much more sensitive detection for manganese-salen complexes when compared with FAB results. No dechlorination or demetalation were observed when a negative ion mode APCI was employed. To our knowledge, this is the first time that an intact molecule of this type of complex has been observed by mass spectrometry.     

在硅磷酸镧中Ce^3＋离子对Tb^3＋离子的敏化

实验表明在La2O3·0.01SiO2·0.95P2O5基质中Ce^3 对Tb^3 有强的敏化作用。254nm紫外光激发下温度对Tb^3 激活的Ce^3 、Tb^3 共激活试样的发射强度的Ce^3 、Tb^3 共激活的试样Tb^3 的^5D4→^7F6:5:4跃迁的发射强度随湿度的变化。计算了Ce^3 到Tb^3 的能量传递效率。初步探讨了Ce对Tb的能量传递机理。     

Rapid Fabrication of Hollow SiO2 Spheres with Novel Morphology

The hydrolysis of tetraethoxysilane (TEOS) occurred on the surface of poly(methyl methacrylate) (PMMA) microshperes immediately after these microshperes were prepared in TEOS. Micron-sized hollow SiO2 spheres were obtained by calcination of the coated PMMA microshperes. It was found that the final hollow spheres were constituted by small SiO2 particles.     

Chiral tris(oxazoline)/Cu(II) catalyzed coupling of terminal alkynes and nitrones

Novel chiral iPr-tris(oxazoline)/Cu(ClO4)2 x 6H2O catalyzed coupling of terminal acetylenes and nitrones to afford cis-disubstituted beta-lactams is described; the choice of base proves essential to both the diastereoselectivity and the enantioselectivity.     

1-(α-萘乙酰基)-4-芳酰基氨基硫脲及3-(α-萘亚甲基)-4-芳酰基-1,2,4-三唑琳-5-硫酮的合成

许多酰氨基硫脲类衍生物有抗病毒、抗细菌、抗肿瘤等功效,我们曾经通过5-(α-萘)-2H-四唑-2-乙酰肼与芳酰异硫氰酸酯缩合得一系列新的酰氨基硫脲和相关的杂环衍生物,观察到它们在很低的浓度下就有调节小麦芽鞘生长的功能。Kothari等用α-萘乙酰肼与芳基异硫氰酸酯缩和制得一系列1-(α-萘乙酰基)-4-芳基氨基硫脲及     

温度及pH敏感的树枝状高分子衍生物合成及药物控制释放研究

对合成的系列聚酰胺-胺型(PAMAM)树枝状高分子进行端基的羟基化和氯乙酰化两步修饰,使PAMAM最外层接上烷基氯.以修饰产物为引发剂,通过原子转移自由基引发甲基丙烯酸N,N-二甲氨基乙酯(DMAEMA)聚合得到树枝状PAMAM高分子衍生物,并对其结构用FTIR、1H-NMR和粒径分析进行了表征.紫外可见分光光度仪测定证实此高分子具有温度及pH敏感性.通过对小分子药物控制释放研究表明,此树枝状高分子衍生物通过环境pH值可有效地控制小分子药物的释放.     

An investigation of the aromaticity of transition metal heterocyclic complexes by conventional criteria and indices of aromaticity

Conventional criteria and indices of aromaticity, including electronic, geometric, energetic and magnetic aspects have been applied to examine the aromaticity of five typical transition metal heterocyclic complexes, i.e. six-membered osmabezene 1 and iridabenzene 2, five-membered cobaltacyclopentadiene 3 and iridacyclopentadiene 4, and four-membered tungstacyclobutadiene 5. The results show that the cyclic, planar, conjugated and Hückel 4n+2 rule’s criteria in the transition-metal-containing heterocycles of the five complexes studied are all met. Five quantitative aromaticity indices, including Bird aromatic index (I_n), homodesmotic reaction aromatic stabilization energy (HASE), absolute hardness (η), diamagnetic susceptibility exaltation (Λ) and NMR chemical shift (δH), qualitatively lead to a consistent and affirmative conclusion that all of them are aromatic. However, they fail to draw a common conclusion for their relative magnitudes of aromaticity, which proves once again the multidimensional character of aromaticity.     

Study of the Complexation Behavior of Calixarene with Transition Metal Cations by UV—vis and Fluorescent Spectra

A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra.