分光光度法工作曲线不符线性关系的探讨 II: 关于在等色点波长测量

光度法工作曲线不成线性关系的情况多数是由体系存在逐级配合物所致, 为获得线性关系, 有人提出在两逐级配合物的主要等色点波长测量, 认为这样可以避免同时生成第二配合物的影响, 但没有深入的理论分析。本文通过实验与理论分析, 证明此法在多数情况下仅可改善线性关系, 但不能得到直线, 经进一步研究, 找到了这个问题的另外解决办法。     

交流示波极谱法中i~f-E曲线的研究 7:基于i~f-E曲线的定量分析方法

本文提出基于i~f-E曲线的定量分析方法,并在自行研制的微机电化学数据采集系统上,测定了微量的Tl^+、Pb^2+、Cd^2+、Zn^2+、Mn^2+和Ga^3+.结果表明,与经典的dE/dt-E曲线方法相比,i~f-E曲线方法的准确度提高了2-5倍、灵敏度提高了一个数量级.     

Interaction between two solid surfaces across PDMS: influence of chain length and end group

Forces between solid surfaces across polymer melts are poorly understood despite their importance for adhesion and composite materials. Using an atomic force microscope (AFM) this force was measured for poly(dimethyl siloxane) (PDMS) on silicon oxide. The influence of molecular weight (4.0–40 kDa) was studied. Forces are attractive for low and repulsive for high molecular weight. In addition, changing the terminal methyl group for a hydroxyl group leads to an increased probability of bridging.     

交流示波极谱法中i~f-E曲线的研究 8:"电极/溶液"界面动态双电层微分电容的快速测量

"电极/溶液"界面动在记双电层微分电容是电极过程动力学中一个重要的物理量,但其测量方法,多数仍停留在对逐一测定的数据点进行作图分析上.本文以i~f-E曲线上电流峰的理论公式为基础,提出了一个快速测量"电极/溶液"界面动态双层微分电容的新方法.     

Probing the properties of particle-matrix interphase in reactive rubber-grafted polybenzoxazine resins by atomic force microscopy

Atomic force microscopy (AFM) is employed to study the amine-terminated poly (butadiene-co-acrylonitrile) (ATBN) rubber-modified polybenzoxazine resin. Topographic mapping of the fracture surface is performed in conjunction with lateral force microscopy (LFM) and force–distance curve measurements (F–d). Matrix T _g reduction is attributed to the dissolved rubber and the increased mechanical damping (tan δ) is derived from the phase-separated rubber. Saturation of the rubber in the matrix is defined at 6 wt% above which the matrix T _g is not influenced upon rubber loading. The solubility limit of the reactive rubber in the matrix phase is determined from the fractured surface using LFM. The torsional force analyzed in the matrix phase increases upon the addition of rubber and levels off at 6 wt%. The results provide a direct correlation between bulk properties acquired by DMA and fractured surface probed by AFM. The presence of interphase between the separated rubbery domain and the continuous matrix phase is confirmed and its thickness is quantified from F–d curves. Moreover, it is found that interphase properties exhibit a strong rubber-concentration dependence.     

水合双邻羟基苄氨乙酸铜配位结构的EXAFS研究

用参数化经验公式, 从已知晶体结构的无水双邻羟基苄胺铜(II)[Cu(o-OC6H4CH2NH2)2, 1]的EXAFS数据中分离出振幅和相移, 拟合另一已知晶体结构的水合双邻羟基苄胺铜(II){[Cu(o-OC6H4CH2NH2)2.H2O].1/2.H2O, 2}的结构参数并进行检验后, 代入未知结构的水合双邻羟基苄氨乙酸铜(II)[Cu(o-HOC6H4CH2NHCH2CO2)2.H2O, 3]中进行曲线拟合, 得到配位原子、键长和配位数等结构信息. 结合红外光谱, 推断标题化合物中, Cu(II)与两个苄基氮和两个羧基氧形成一个平面四边形的配位结构.铜与羧基氧键长2.00A, Cu-N键长1.99A, 另有一个较远的配位水分子, 铜与水的氧距离2.95A. 配体上的酚基氧没有与Cu(II)配合. 因此, 邻羟基苄氨乙酸(HBG)与Cu(II)配位时表现为二啮形式.     

气相色谱过程动力学研究-柱压降对色谱流出曲线的影响

本文在色谱质量平衡模型基础上, 考虑到气相色谱过程中柱压降与载气线速的关系, 建立了考虑柱压降的气液分配色谱质量平衡模型。通过数学变换的方法, 得到了流出曲线一级矩及二级、三级中心矩的数学表达式。理论和实验均表明: 溶质的保留时间, 流出峰半峰宽与柱前压倒数近似呈线性关系; 柱压降对柱效及峰形对称性也有影响。     

Nafion修饰电极还原计时电位溶出法的理论和验证

本文推导了Nafion修饰电极还原计时电位溶出法的过渡时间和电位-时间曲线方程式。经过验证,实验结果与理论相符。     

倒数示波计时电位法

使用dE/dt的倒数对E作图的示波计时电位法,称为倒数示波计时电位法.dE/dt-E曲线上的切口在dE/dt^-1-E上变成峰,可以方便地扣除充电电流,提高分析测试的灵敏度.     

塔板理论色谱流出曲线性质的研究

塔板理论是色谱动力学理论的重要部分。本文采用数学方法把塔板理论色谱流出曲线从离散函数形式变换为连续函数形式。在此基础上运用计算机进一步研究了塔板理论色谱流出曲线的性质。