基于小波变换的CCD光谱信号消噪及汽车车灯颜色测试的应用研究

研制了一种新型测色系统。依据小波变换理论 ,对颜色测量中所接收到的光谱信号采用了小波变换消噪平滑数据处理技术 ,提高了系统测色的精度。采用CCD作为光电转换元件 ,接收汽车车灯光谱并转换为电信号 ,提高了测量速度。给出了CCD关于颜色测量的光谱标定方法。通过测量色度值与其标准色度值比较 ,所得偏差Δx≤ 0 0 0 8,Δy≤ 0 0 0 8;重复性Δx≤ 0 0 0 8,Δy≤ 0 0 0 8。     

Synthesis of a New Family of Green Light Emitting Material Containing Both Hole and Electron Transporting Units

Since Tang and Van Slyke reported the first double-layer organic electroluminescent (EL) device using Alq3 (q = 8-hydroxyquinolinyl) in 19871, organic EL devices have received a great deal of attention in view of their application as full-color flat-panel displays as well as academic interest2,3,4. There have been extensive studies of organic EL devices directed toward achieving high brightness and multi- or full-color emission, and in particular, improving the durability and thermal stabi…     

Rate of convergence for Meyer-König and Zeller operators with Jacobi-Weights

We point out that the Meyer-Konig and Zeller operator M. (f;x) are unbounded in usual Jacobiweighted norm at first, and then we consider the weighted approximation by M.(f ;x) by a new norm andobtain the characterization of convergence rate in nonoptimal approximation by K-functional.     

多圆盘上的Toeplitz算子的紧的乘积

对于多圆盘上的有界多重调和函数f,g,我们证明多圆盘Bergman空间上的Toeplitz算子的乘积TfTg是紧算子的充要条件是TfTg是零.这等价于f或g是零.换位子TfTg-TgTf是紧算子当且仅当换位子TfTg-TgTf是零.这等价于对每一个j,存在不全为零的常数αj和βj,使得αjf+βjg关于变量zj(1≤j≤n)是常数.     

新的4′-去甲表鬼臼衍生物的2D NMR研究

采用¹H-¹H COSY、NOESY、¹H-¹³C HMQC及HMBC二维NMR技术鉴定了2个新合成的4β-5- 氟尿嘧啶取代-4′-去甲表鬼臼毒衍生物, 并对它们的¹H和¹³C NMR 谱峰进行了全归属.     

基于Ohlson模型的企业权益价值自适应估计

企业价值估计是投资的基础.1995年,J.Ohlson将超额收益RI（Residual Income）用于企业价值估价,形成了企业价值估价的一个分支.然而,Ohlson模型要求正确估计收益率和未来各期的超额收益,在应用上有明显的局限性.本文以Ohlson超额收益估价模型为基础,结合Gordon增长模型,建立了一个企业权益资本价值估价新模型.对该模型的参数估计,我们采取逐步迭代的方法,逐步吸收企业成长过程中的信息,不断修正模型参数,直至得到“满意”的参数.我们证明了这个参数估计过程是收敛的,因此新模型有更好的可操作性.     

Lagrange multipliers for functions derivable along directions in a linear subspace

We prove a Lagrange multipliers theorem for a class of functions that are derivable along directions in a linear subspace of a Banach space where they are defined. Our result is available for topological linear vector spaces and is stronger than the classical one even for two-dimensional spaces, because we only require the differentiablity of functions at critical points. Applying these results we generalize the Lax-Milgram theorem. Some applications in variational inequalities and quasilinear elliptic equations are given.

     

走近物理学大师--宾尼格印象记

多年来在海外访问工作，有幸会面了不少物理学大师，他们的音容笑貌至今萦回耳畔脑际；其中印象最深的当数宾尼格（Gerd Binnig）先生．     

Microwave-assisted one-pot regioselective synthesis of 2-alkyl-3,4-dihydro-3-oxo-2H-1,4-benzoxazines

A protocol for regioselective one-pot synthesis of 2-alkyl-3,4-dihydro-3-oxo-2H-1,4-benzoxazines under controlled microwave heating has been developed. Starting from commercially available 2-aminophenols, a base-mediated regioselective O-alkylation took place with 2-bromoalkanoates to give the acyclic intermediates, which underwent spontaneously an intramolecular amidation reaction to furnish 2-alkyl-3,4-dihydro-3-oxo-2H-1,4-benzoxazines in 44-82% yields. For the acyclic intermediate possessing an electron-withdrawing group, microwave heating was necessary for the annulation reaction.