工业Fe-Mn催化剂上费托合成反应动力学的研究

使用工业Fe-Mn催化剂,以搅拌釜反应器的实验数据为依据,受计算量子化学研究结果的启发,考察了两类费托合成反应机理,建立了相应的反应动力学模型并与文献模型进行了比较。结果表明,CO在氢参与下经含氧中间体解离的机理给出了最优的动力学模型,其与文献的结论一致。     

Rapid microwave assisted hydration of internal arylalkynes in the presence of PTSA: an efficient regioselective access to carbonyl compounds

A metal-free procedure for the regioselective hydration of internal arylalkynes under microwave irradiation is described. The reaction promoted by PTSA takes place rapidly in EtOH and regioselectively afforded in good yields various carbonyl compounds 2.     

Liquid chromatography with diode array detection and multivariate curve resolution for the selective and sensitive quantification of estrogens in natural waters

Following the green analytical chemistry principles, an efficient strategy involving second-order data provided by liquid chromatography (LC) with diode array detection (DAD) was applied for the simultaneous determination of estriol, 17β-estradiol, 17α-ethinylestradiol and estrone in natural water samples. After a simple pre-concentration step, LC–DAD matrix data were rapidly obtained (in less than 5 min) with a chromatographic system operating isocratically. Applying a second-order calibration algorithm based on multivariate curve resolution with alternating least-squares (MCR-ALS), successful resolution was achieved in the presence of sample constituents that strongly coelute with the analytes. The flexibility of this multivariate model allowed the quantification of the four estrogens in tap, mineral, underground and river water samples. Limits of detection in the range between 3 and 13 ng L⁻¹, and relative prediction errors from 2 to 11% were achieved.     

ICP—AES中基体干扰效应及其机理研究：Ⅱ.干扰现象的进一步探讨

本文探讨了共存元素对碱金属以及Al对碱土金属的基体效应,测定了不同基体浓度、入射功率及载气压力时一般基体效应分布的变化,并观察了3种基体对Cd、Fe电离度的影响。在尾焰区,碱金属发射信号受到共存基体的明显增感,增感幅度随观察高度的增加而增大;Al基体对碱土金属产生抑制作用,抑制幅度随观察高度的升高而下降;基体干扰(增感或抑制)的幅度随基体浓度及载气压力的增加而增大,随入射功率的增加而减小。     

Simultaneous singular value decomposition

We consider the following problem: Given a set of m×n real (or complex) matrices A₁,…,A_N, find an m×m orthogonal (or unitary) matrix P and an n×n orthogonal (or unitary) matrix Q such that P^*A₁Q,…,P^*A_NQ are in a common block-diagonal form with possibly rectangular diagonal blocks. We call this the simultaneous singular value decomposition (simultaneous SVD). The name is motivated by the fact that the special case with N=1, where a single matrix is given, reduces to the ordinary SVD. With the aid of the theory of *-algebra and bimodule it is shown that a finest simultaneous SVD is uniquely determined. An algorithm is proposed for finding the finest simultaneous SVD on the basis of recent algorithms of Murota-Kanno-Kojima-Kojima and Maehara-Murota for simultaneous block-diagonalization of square matrices under orthogonal (or unitary) similarity.     

Delta算子Riccati方程研究的新结果

基于Delta算子描述，统一研究连续时间代数Riccati方程(CARE)和离散时间代数Riccati方程(DARE)的定界估计问题，提出了统一代数Riccati方程(UARE)解矩阵的上下界，给出UARE中P与R和Q的几个基本关系．     

Integral representation with weights II, division and interpolation

Let f be a r×m-matrix of holomorphic functions that is generically surjective. We provide explicit integral representation of holomorphic ψ such that ϕ=f ψ, provided that ϕ is holomorphic and annihilates a certain residue current with support on the set where f is not surjective. We also consider formulas for interpolation. As applications we obtain generalizations of various results previously known for the case r=1. The author was partially supported by the Swedish Research Council     

计算分光光度法同时测定铁、铝、钪

基于铬天青Ｓ－ＣＴＭＡＢ－丙酮与Ｆｅ,Ａｌ,Ｓｃ的显色体系中各组分吸收光谱灵敏度,而选择性差的特点,本文提出一种改进矩阵法,并同时测定了合成样品中三组分的含量取得了满意结果。     

The alternating-direction iterative method for saddle point problems

In the paper, a new alternating-direction iterative method is proposed based on matrix splittings for solving saddle point problems. The convergence analysis for the new method is given. When the better values of parameters are employed, the proposed method has faster convergence rate and less time cost than the Uzawa algorithm with the optimal parameter and the Hermitian and skew-Hermitian splitting iterative method. Numerical examples further show the effectiveness of the method.     

线性流形上的矩阵最佳逼近

令Ｓ＝｛Ａ∈Ｒｎ×ｍ｜ｆ１（Ａ）＝‖ＡＸ１－Ｚ１‖２＋‖ＹＴ１Ａ－ＷＴ１‖２＝ｍｉｎ｝，其中Ｘ１∈Ｒｍ×ｋ１，Ｚ１∈Ｒｎ×ｋ１，Ｙ１∈Ｒｎ×１１和Ｗ１∈Ｒｍ×１１均为给定的矩阵，‖·‖是Ｆｒｏｂｅｎｉｕｓ范数。本文考虑如下问题：问题Ⅰ给定Ｘ２∈Ｒｍ×ｋ２，Ｚ２∈Ｒｎ×ｋ２，Ｙ２∈Ｒｎ×ｌ２，Ｗ２∈Ｒｍ×ｌ２，求Ａ∈Ｓ，使得ｆ２（Ａ）＝‖ＡＸ２－Ｚ２‖２＋‖ＹＴ２Ａ－ＷＴ２‖２＝ｍｉｎ．问题Ⅱ给定Ａ∈Ｒｎ×ｍ，求Ａ∈ＳＡ，使得‖Ａ－Ａ‖＝ｉｎｆＡ∈ＳＡ‖Ａ－Ａ‖，其中ＳＡ是问题Ｉ的解集合。本文给出问题Ｉ解集合ＳＡ的通式和问题Ⅱ的解Ａ的表达式，提出了求解问题Ⅰ与Ⅱ的数值方法。许多文献的结果都是本文结果的特例。