CIS-双(氯乙酸)一2,3一二甲基一2,3一丁二胺合铂配合物的晶体结构和电子结构

测定了CIS-双(氯乙酸)-2,3-二甲基-2,3-丁二胺合铂,CIS-[PtDMBA(ClCH2CO2)2]配合物的晶体和分子结构。晶体的空间群为P212121。晶胞参数a=9.866(4)A,b=16.356(2)A,c=19.501(4)A;Z=8。由Pattersou函数导出Pt原子坐标参数,Fourier和差值Fourier电子密度函数法得到全部非氢原子坐标参数,用块矩阵最小二乘法精修所有的结构参数,最终一致性因子r值为0.061。每个分子中,Pt(II)取四配位平面四边形构型。DMBA以及双齿与Pt(II螯合成五元环。分子中N-Pt-N-和O-Pt-O的平均键角分别为80.3℃和80.8℃。由于DMBA螯合配位,使平面正方形畸变,与Pt配位的两个氯乙酸根的键合原子间距离为2.6A。用CNDO/2方法研究了配合物电子结构,解释了配合物具有较特殊的O-Pt-O,N-Pt-O-键角的原因,并讨论了配合物的结构与抗癌活性间的关系。     

2, 5-二间氮杂氧茚氢醌激发态质子转移反应机理的研究

用AM1+INDO/SDCI方法对2, 5-二间氮杂氧茚氢醌分子内激发态质子转移反应进行了理论研究, 求得了基态和激发态反应的位能面、势垒、过渡态, 并对有关化合物的光谱进行了理论指认, 所有理论计算结果均与实验结果符合较好。在此基础上对反应机理进行了探讨, 认为有利的是单质子转移反应不是双质子转移反应。     

Direct local and global approximation theorems for some linear positive operators

In this paper we establish direct local and global approximation theorems for Baskakov type operators and Szasz - Mirakjan type operators, respectively.     

APPROXIMATION PROPERTIES OF (C, α) MEANS OF DOUBLE WALSH-FOURIER SERIES

We study the rate of Zp approximation by Cesaro means of the quadratic partial sums of double Walsh-Fourier series offu nctions from Lp.     

On Gravitational Radiation Graviton Number Density: Application to a Nambu String

A formalism is developed to compute the number density of gravitons, of specified energies, produced by an arbitrary external energy-momentum tensor source at any temperature. The formalism is applied to a simple Nambu string without making the usual assumption of a long wavelength approximation (L.W.A.). This exact result is also compared to the L.W.A.     

Equivalent theorems on simultaneous approximation by combinations of Bernstein operatores

In this paper we give equivalent theorems on simultaneous approximation for the combinations of Bernstein operators by r-th Ditzian-Totik modulus of smoothness ωτψλ (f, t)(0 ≤λ≤ 1). We also investigate the relation between the derivatives of the combinations of Bernstein operators and the smoothness of derivatives of functions.