铂配位的腺嘌呤质子化的理论研究

用量子化学从头算研究一系列平面四方金属配体作用于腺嘌呤N₇位点对其质子化的影响。计算结果表明气相中，配合物质子化能力主要受长程静电效应影响，不同金属离子的影响差别甚微。综合考虑极性溶剂影响后长程静电效应影响显著降低。NBO电荷布居分析表明质子化位点电子云密度的变化直接影响该位点质子化能力。     

顺铂化合物与鸟嘌呤异构体相互作用的理论研究

The influence of binding of cisplatin adducts on tautomeric equilibrium of guanine was investigated using quantum chemical method. The monoaqua adduct [Pt（NH3）2Cl（H2O）]^＋ and the diaqua adduct [Pt（NHa）2（H2O）2]^2＋ were chosen for coordination to the N（7） site of guanine tautomers. The results demonstrate that the platinum adducts influence moderately on tautomeric equilibrium, but do not change the relative stability of tautomers whether in gas phase or in aqueous solution. The keto form having H atom at N（1） and N（9） was always the predominant structure when cisplatin adducts were bound to guanine. However, other forms could coexist in water. Meanwhile, our calculations suggest that the tautomeric equilibrium should be via the same intermediate.     

Pt(Ⅱ), Pd(Ⅱ) and Ni(Ⅱ) Complexes Binding to the N(7) Position of Guanine: Influence on the Guanine and Watson-crick GC Base Pair

Comprehensive ab initio calculations were performed on the coordination of Pt(Ⅱ),Pd(Ⅱ) and Ni(Ⅱ) adducts to the N(7) of guanine and guanine-cytosine (GC) base pair at the DFT level. The fully optimized geometries of the metal complexes were obtained and the stabilization energies of the interaction between metal adducts and nucleobase were calculated with B3LYP method by using 6-31^* basis set for the light atom. While the effective core potential (ECP) is used for metal cation. The results show that both cispalladium and cisnickel cause similar geometric changes of the base pair as cisplatin. For the coordination of metal adducts to guanine, platinum adduct possesses the highest stabilization energy; but the interaction between metal-guanine and cytosine for nickel is larger than that for platinum and palladium. It is worthy to note that hydrolysis effect can also cause significant changes in H-bonds.     

让学生在解题中学会学习

解题是学生巩固所学知识 ,提高应用能力 ,培养良好思维品质的重要手段 .学生学习数学的大半时间是在解题中度过的 .在当前“以学生发展为本”的教学理论指导下 ,如何让学生真正成为解题的主人 ,让学生在解题中学会思维 ,学会学习 ,应成为我们研究的课题 ,本文仅从解题教学的几个侧面谈一些个人的体会 .1　引导学生探索解题的途径 ,揭示发现解题方法的思维过程经常有学生问我 ,老师的解题方法是怎样想出来的 ?有时真还说不清楚 .因为方法的得来是数学知识点的掌握 ,数学思想和方法的自然运用 ,是解题经验的不断积累基础上的一种灵感闪现 ,是…