二-(2-乙基己基)磷酸-煤油液膜萃取锌(Ⅱ)的动力学分析

锌离子;二乙基己基磷酸;迁移动力学;二-(2-乙基己基)磷酸-煤油液膜萃取锌(Ⅱ)的动力学分析     

N,N-二甲基胺乙基膦酸-磷酸氢锆为载体的新型固体碱研究

催化;缩合反应;N;N-二甲基胺乙基膦酸-磷酸氢锆为载体的新型固体碱研究     

非磁性替代原子对Ce2Co17居里温度和饱和磁化强度的影响

用真空电弧熔炼法制备了Ｃｅ２Ｃｏ１７－ｘＭｘ（Ｍ＝Ｇａ,Ａｌ和Ｓｉ）化合物。通过Ｘ射线衍射和磁性测量手段,研究了非磁性替代原子Ｇａ,Ａｌ和Ｓｉ的加入对Ｃｅ２Ｃｏ１７化合物的剧里温度和饱和磁化强度的影响,其中Ｓｉ在Ｃｅ２Ｃｏ１７化合物中的固溶度最小,并使居里温度和饱和磁化强度下降幅度最大。     

Kinetic model of induced codeposition of Ni-Mo alloys

The kinetic model of induced codeposition of nickel-molybdenum alloys from ammoniun citrate solution was studied on rotating disk electrodes to predict the behavior of the electrode-position. The molybdate (MoO42-) could be firstly electro-chemically reduced to MoO2, and subsequently undergoes a chemical reduction with atomic hydrogen previously adsorbed on the inducing metal nickel to form molybdenum in alloys. The kinetic equations were derived, and the kinetic parameters were obtained from a comparison of experimental results and the kinetic equations. The electrochemical rate constants for discharge of nickel, molybdenum and water could been expressed as k1(E) = 1. 23 × 109 CNi exp( - 0.198FE/RT) mol/(dm2·s), k2(E) =3.28× 10-10 CMoexp( - 0. 208FE/ RT) mol/(dm2·s) and k3(E) = 1.27 × 10-6exp( - 0.062FE/ RT) mol/(dm2 · s), where CNi and CMo are the concentrations of the nickel ion and molybdate, respectively, and E is the applied potential vs. saturated calomel electrode (SCE). The codeposition p     

Synthesis and Properties of Axial Coordination Reaction of Unsymmetric Leucine Zinc(Ⅱ) Tetraphenylporphyrin with Pyrimidine

In recent years much work has been done on the syntheses and properties of axial coordination reaction of zinc tetraphenylporphyrins with nitrogenous donors in order to better understand the detailed molecuar mechanism of natural zincous enzymes. However,only a few studies have been reported in which the nitrogenous donors are bound to the amino acid metallotetraphenylporphyrins with unsymmetric structures. In this paper, a new unsymmetric leucine tetraphenylporphyrin, 5-(4-leucine butoxyphenyl)-10,15,20-triphenylporphyrin (H₂[Leu-TPP]) and its Zn(Ⅱ) complex (Zn[Leu-TPP]) are synthesized. Their structures are characterized by elemental analysis, UV, IR, fluorescense spectra. The changes of the electronic absorption spectra of axial coordination reaction of Zn[Leu-TPP] with pyrimidine in chloroform are investigated Coordination number (n) and equilibrium constant (β) of the reaction are measured by visible spectra techniques. The changes of standard molar enthalpy (Δ_rH_m^⊙) and molar entropy (Δ_rS_m^⊙) of the reaction are calculated. The obtained data are listed in table 1.     

酶促合成油酸香茅醇酯的超临界连续反应-分离过程

将固定床动态酶促反应过程和超临界二氧化碳萃取分离过程相耦合,设计并建立了一套超临界相反应分离一体化的实验装置。在该装置上初步考察了反应压力和温度对脂肪酶催化油酸甲酯和外消旋香茅醇酯交换反应的影响。结果表明,我们所建立的反应装置能有效地实现反应分离一体化过程;当体系压力接近二氧化碳的临界压力时反应速率最高;9MPa压力下反应温度为328K时反应转化率最高,而在14MPa压力下反应转化率在308K～328K之间随着温度的升高而增大。     

沙蚕磷草酸盐的合成与晶体结构

合成了一种新的有机磷杀虫剂沙蚕磷[O,O,O',O'-四甲基－S,S'-(2-N,N-二甲氨基-1,3-亚丙基)-双-二硫代磷酸酯],并制备了它的草酸盐。测定了沙蚕磷草酸盐的晶体结构,结果表明,该晶体属三斜晶系,P1空间群,晶胞参数为:a=0.74342(5)nm,b=1.1057(4)nm,c=1.45295(11)nm,α=98.018(11)°,β=101.012(4)°,γ=96.224(10)°,Z=2。通过元素分析,MS、IR及^1H,^1^3CNMR表征了该化合物的结构。     

带非线性源项的变分不等式的区域分解法及其收敛速度分析

本文考虑一类带非线性源项的变化不等式。针对其有限元离散问题,我们构造了乘性与加性Ｓｃｈｗａｒｚ算法,其产生的上解序列或下解序列不仅单调收敛于有限元解,而且具有限元网格ｈ无关的收敛率．     

非自治系统渐近稳定的充分条件

本文对 Liapunov关于渐近稳定性的基本定理进行改进 ,在附加辅助函数前提下 ,同时放宽了 V正定 ,有无穷小上界 .V负定的条件 .改进了文 [1 ]～ [6]相应结果     

Evolution of non-synchronized binary systems

A model for binary evolution is introduced which can determine whether the rotation of components is synchronized with the orbital motion, and can calculate the evolution of both the synchronized and non-synchronized binary systems. With this model, the evolution of a binary system consisting of a 9 M_⊙ star and a 6 M_⊙ star is studied with mass transfer Case B. The result shows that the synchronization of the rotational and orbital periods can be reached when the binary system is a detached system and before the occurrence of the first mass transfer. After the onset of the first mass transfer, the binary system becomes non-synchronized. The mass accepted component (the secondary) rotates faster with a period much smaller than that of the orbital motion.