季铵酚离子在水／硝基苯界面的转移

油/水界面上的电化学研究是近年来电化学研究中的一个新领域,对膜电化学的发展具有重要意义。目前研究油/水界面电化学中普遍使用循环伏安(CV)法和循环线扫电流计时电位(CLC)法。有关抗生素在油/水界面的转移已有报导,本文用CLC法和CV法对肌肉松弛剂季铵酚离子在水/硝基苯界面的转移行为进行了研究。 所用三碘季铵酚为中国科学院生物化学研究所生产的化学试剂,其他试剂及仪器均与前文相同     

添加0.1%Ce对Sn-3.0Ag-0.5Cu焊料与铜基板间的金属间化合物的影响

研究了Sn-3.0Ag-0.5Cu-xCe（x=0,0.1%）焊料合金与Cu基板250℃钎焊及170℃恒温时效时对基体和界面金属间化合物（IMC）的形成与长大行为的影响。结果发现,在Sn-3.0Ag-0.5Cu焊料中添加0.1?后,能够抑制基体和钎焊界面反应及随后时效过程中IMC的形成与生长。焊点最初的界面IMC为Cu6Sn5,时效5 d之后,该两钎焊体系中均发现了Cu3Sn薄层的生成,且随着时效时间的增加,各IMC层厚度有明显的增加趋势。与Sn-3.0Ag-0.5Cu/Cu焊点相比,Sn-3.0Ag-0.5Cu-0.1Ce/Cu钎焊体系焊点界面处的IMC层更为平整和细薄。时效过程中,界面IMC的形成与长大受扩散机制控制。     

基于软件编码的FLEX高速寻呼测试仪的研制

基于FLEX和POCSAG寻呼协议,采用单片机AT89C55为控制核心,以MCS-5l汇编语言实现软件编码,研制了一套兼容POCSAG协议的FLEx高速寻呼测试仪．本文详细讨论了实现FLEx高速寻呼协议的软件编码技术．在对数据块进行交织时,提出了一种简化的软件编码措施,将多相复用模式的交织数据块简化为单相模式进行处理,从而减小了编码难度．     

Preferential oxidation of CO in excess H2 over the CeO2/CuO catalyst： Effect of initial support

Three series of CeO2/CuO samples were prepared by impregnation method and characterized by XRD, N2adsorption-desorption, temperatureprogrammed reduction(TPR), XPS and TEM techniques. In comparison with the samples prepared with CuO as initial support, the samples with Cu(OH)2as initial support have higher reducibilities and smaller relative TPR peak areas, and also larger specific surface areas at calcination temperatures of 400℃–600℃. As a result, Cu(OH)2is better than CuO as initial support for preferential oxidation of CO in excess H2(CO-PROX). The best catalytic performance was achieved on the sample calcined at 600℃ and with an atomic ratio of Ce/Cu at 40%. XPS analyses indicate that more interface linkages Ce-O-Cu could be formed when it was calcined at 600℃. And the atomic ratio of Ce/Cu at 40%led to a proper reducibility for the sample as illustrated by the TPR measurements.     

一种考虑层间位移和横向剪应力连续条件的层合板理论

本文建立了一种新的层合板理论。该理论满足层间位移和横向剪应力连续条件以及上下表面横向剪应力协调条件，其控制方程仅包含五个未知量。数值算例表明该理论具有很高的精度。     

First Principles Study of Half Metallic Properties of VSb Surface and VSb/GaSb （001） Interface

The structural, electronic, and magnetic properties of VSb in zincblende, and NiAs phases, VSb （001） film surfaces and its interfaces with GaSh （001） have been investigated within the framework of the density functional theory using the FPLAPW＋lo approach. The NiAs structure is more stable than the ZB phase, ZB VSb is found to a half-metallic ferromagnetic. The V-terminated surfaces retain the half-metallic character, while the half-metallicity is destroyed for Sb-terminated surfaces due to surface states, which originate from p electrons. The phase diagram obtained through the ab-initio atomistic thermodynamics shows that the formation energy of ZB VSb is about 0.1 Ryd. The half-metallicity character is also preserved at VSb/GaSb （001） interface. The conduction band minimum （CBM） of VSb in the minority spin case lies about 0.47 eV above that of GaSb, suggesting that the majority spin can be injected into GaSb without being flipped to the conduction bands of the minority spin.     

不可约对称三对角矩阵根的隔离定理的推广

１引言设ｎ×ｎ不可约对称三对角矩阵Ｔｐ,ｑ记它的子阵记Ｔｐ,ｑ的特征多项式ｄｅｔ（λI一Ｔｐ,ｑ）=φｐ,ｑ(λ）·于是φ1.ｎ(λ）＝ｎ（λ）即为Tｎ的特征多项式.所谓根的隔离定理,即为：Ｔ1,ｎ－１或Ｔ２,ｎ的特征值和Ｔｎ的特征值满足参见［１,ｐ．３６］．这是对称三对角矩阵的重要性质,在研究求特征值的二分法和特征值反问题时都有用到．这个定理讲的是Ｔｎ与划去第一行,第一列后的矩阵,或划去第ｎ行,第ｎ列后的矩阵Ｔ２,ｎ或Ｔ１,ｎ－１特征值之间的关系．本文将此关系推广到Ｔｎ划去第ｋ行,第ｋ列ｋ＝１,２,…,…     

An Extension of the Roots Separation Theorem

Let T _n be an n×n unreduced symmetric tridiagonal matrix with eigenvalues ₁<₂<< _n and W _k is an (n–1)×(n–1) submatrix by deleting the kth row and the kth column from T _n , k=1,2,...,n. Let _{12 n–1} be the eigenvalues of W _k . It is proved that if W _k has no multiple eigenvalue, then ₁<₁<₂<₂<< _n–1< _n–1< _n ; otherwise if _i = _i+1 is a multiple eigenvalue of W _k , then the above relationship still holds except that the inequality _i < _i+1< _i+1 is replaced by _i = _i+1= _i+1.