Electrochemical behavior of a series of azobenzene self-assembled monolayers on gold

Conclusion This work shows that the structures of C_n AzoC₂ (n = 1, 2, 3, 4) SAMs are significantly different and influence the observed electrochemical behavior of these novel azobenzene systems. The sluggish electron-transfer kinetics of azobenzene SAMs were explained by the alkyl spacer between azobenzene and electrode, the spatial inhibition for structural change in the redox process of azobenzene, as well as the ion-transportation barriers. For decrease of the apparent electrontransfer rate constants with increasing the length of end-groups, and the electrochemical inaccessibility of C₄AzoC₂ SAMs, the spatial inhibition for structure conformational change and ion-transportation was considered as the predominant factor.     

链霉菌M1033葡萄糖异构酶的分离纯化及其性质的研究

链霉菌M1033菌株所产的葡萄糖异构酶培养液经二级(NH_4)_2SO_4沉淀、DEAE-Sephadex A50,Sephadex-G150柱层析分离纯化,可得到电泳均一的纯酶。该酶的全分子量为91000左右,由两个相同的亚基组成。其pI为4.3,经糖染色后证明并非糖蛋白;最适反应温度70℃,在该温度下分别以D-木糖和D-葡萄糖为底物,测得最适pH分别为8.0和8.3。该酶为金属激活酶。Co~(2 )和Mg~(2 )对该酶有激活作用,Ca~(2 )则使之几乎失活。金属离子的激活作用随底物而异。动力学研究表明,该酶对D-木糖有更大的亲和性。     

求解离子光学系统高阶轨迹方程的新方法

本文讨论求解离子光学系统高阶轨迹方程的逐次积分方法。计算轨迹方程齐次解的积分,可以直接建立轨迹方程非齐次项的G矩阵与该非齐次方程的特解轨迹S矩阵的转换关系。把这个关系归结为特解生成矩阵。按照这种改进的理论方法,高阶轨迹的求解简化成为G矩阵与L矩阵的相乘,S矩阵各元素间的某些相互关系亦同时被清晰显示。     

一种新的模拟电路K故障诊断方法

论证了在线性网络Ｎ中包含有：ｔ－ｌ条树支支路的ｔ条支路有故障时．利用多激励 Ｉｍｍ必可得到包含有 ｔ－ｌ个独立向量的测试向量组△Ｖｍｍ提出利用这组秩为ｔ－ｌ的测试向量组△Ｖｍｍ快速定位故障元件的方法，使求秩运算由Ｃｎｋ（Ｃｂｋ或Ｃｂ１）次减少到１次。这种快速故障定位方法不仅适用于Ｋ支路故障诊断，也适用于Ｋ节点故障诊断。     

1,2,3,6-四氢化邻苯二甲酸酐异构化反应研究

本文在气相色谱分析的基础上,研究了1,2,3,6-四氢化邻苯二甲酸酐在各种路易士酸催化下的反应情况,并对以对甲苯磺酸为催化剂的反应进程提出了通过碳正离子中间体的可能机理。     

EFFECT OF N~+ ION IMPLANTATION ON SURFACE ROUGHNESS OF 40Cr STEEL

The different change tendencies of 2-and 3-dimensional surface roughnesses of 40Cr steel aremeasured and analysed.In 2-dimensional parameters,the data are measured amplitude parametersR_a ,R_q ,R_(pn),spacing parameters S_m,S,q and shape parameters Δq,T_p %,R_(sk),R_(ku)..In3-dimensional parameters,the similar amplitude and shape parameters are measured.The au-thors found that ion implantation lcads to reduction of the values of the amplitude parameters ofthe surface roughness remarkably.The values of the spacing parameters have no regular changes.The changes of surface profiles before and after ion implantations have been measured in detail.Inaddition,the auto-correlation function and the power spectrum are analysed for the surfaces ofdifferent implanting parameters.It is concluded that in the observed frequency range,the intensi-ties of various frequencies decrease widely and the coefficients of the auto-correlation of surfacesdecrease after ion implantation.