具固定脉冲时刻的脉冲微分系统关于部分变元的指数稳定性

研究了具固定脉冲时刻的脉冲微分系统关于部分变元的指数稳定性,得到了保证零解关于部分变元指数稳定的充分条件,并给出了关于部分变元稳定性的一个新的判定准则.最后给出了其相关例子.     

Attempt to generalize fractional-order electric elements to complex-order ones

The complex derivative D~(α±jβ), with α, β∈ R+ is a generalization of the concept of integer derivative, where α = 1,β = 0. Fractional-order electric elements and circuits are becoming more and more attractive. In this paper, the complexorder electric elements concept is proposed for the first time, and the complex-order elements are modeled and analyzed.Some interesting phenomena are found that the real part of the order affects the phase of output signal, and the imaginary part affects the amplitude for both the complex-order capacitor and complex-order memristor. More interesting is that the complex-order capacitor can do well at the time of fitting electrochemistry impedance spectra. The complex-order memristor is also analyzed. The area inside the hysteresis loops increases with the increasing of the imaginary part of the order and decreases with the increasing of the real part. Some complex case of complex-order memristors hysteresis loops are analyzed at last, whose loop has touching points beyond the origin of the coordinate system.     

热处理工艺对铸造汽车覆盖件模具钢的耐磨性研究

对不同淬火、回火温度与不同磨损条件下的铸造汽车覆盖件模具钢进行了磨损试验,研究磨损率与回火温度、摩擦参数等因素的关系,观察摩擦表面的显微组织和摩擦学性能.结果表明:试验用模具钢材料的耐磨性能与材料的硬度有一定关系,与淬火、回火温度有很大关系,更与磨损过程中加载载荷、滑动速率和摩擦距离等因素有关.回火温度对模具钢材料的硬度和耐磨性起到了一定的作用,500℃左右时硬度最大.600℃回火后,组织中主要成分变为马氏体与托氏体.在滑动速率较高、回火温度较低时,随着回火温度升高,磨损率降低速度明显;在加载载荷较大、回火温度较低时,随着回火温度的升高,磨损率降低速度明显.不同的滑动速率以及加载载荷情况下的磨损机理主要为黏着磨损和磨粒磨损等两种.     

基于三幅子图的干涉合成孔径雷达数据处理方法研究

现有干涉合成孔径雷达(InSAR)数据处理方法需要单视复图像对包含的所有四幅子图信息, 且生成的干涉相位图去相关噪声非常严重。提出了基于三幅子图的InSAR数据处理方法：等值线相关干涉法, 包括图像对配准和干涉相位图生成。首先介绍了条纹方向图和条纹等值线窗口求取的方法, 并对算法进行了改进, 然后采用相关的方法详细推导了在等值线窗口内InSAR图像的配准和干涉相位图生成的公式。模拟和实测数据表明, 等值线相关干涉法(CCI方法)仅需用InSAR复数图像对的4个实虚部子图中任意3个能得到基本无斑点噪声、无模糊效应的干涉相位图, 并且减少了数据的传输和处理量, 是一种InSAR数据处理的全新方法。     

A Chebyshev polynomial method for line integrals with singularities

In this paper we consider a Chebyshev polynomial method for the calculation of line integrals along curves with Cauchy principal value or Hadamard finite part singularities. The major point we address is how to reconstruct the value of the integral when the parametrization of the curve is unknown and only empirical data are available at some discrete set of nodes. We replace the curve by a near‐minimax parametric polynomial approximation, and express the integrand by means of a sum of Chebyshev polynomials. We make use of a mapping property of the Hadamard finite part operator to calculate the value of the integral. This revised version was published online in June 2006 with corrections to the Cover Date.     

轨迹成型法加工球面光学零件新原理的研究

针对在现行球面光学零件加工的基本工序中存在的问题，提出了用轨迹成型法加工球面光学零件的新原理，并对其进行了深入研究。轨迹成型法加工新原理是零件在自身旋转的同时，以某一设定的曲率半径摆动的复合运动与磨轮的圆周运动相互干涉，形成凸或凹的球面。此加工原理的机床能够使加工工序集中化、磨床多用化、加工范围扩大化，而且使工件的面形精度和表面粗糙度容易得到保证，并且加工效率得到了提高，加工成本得到了降低。因此，该加工原理具有广泛的推广应用价值。     

Vibrational lifetime measurements of matrix isolated molecules by an optical “double resonance” method

An optical-optical “double-resonance” experiment has been developed and successfully applied to the study of vibrational lifetimes. This pulsed dual laser technique should be applicable to all species possessing resolvable allowed vibronic transitions and it permits the direct measurement of vibrational lifetimes which, at present, may be as short as 20 μs. Application of this technique to the υ″ = 1 and υ″ = 2 states of matrix isolated C₂^? yields half lifes of 0.2 and 1.2 ms, respectively, in an argon matrix at 16K, and 0.3 and 1.3 ms in an N₂ matrix at 14K. No significant temperature variation of these rate constants has been found in the range 14 to 24 K. This is the first direct measurement of the vibrational lifetime of a homonuclear diatomic molecule isolated in a matrix environment.     

Amperometric titration of copper in brass

A direct amperometric titration of copper is described; o-(p-tolylsulfonamido) aniline serves as titrant. The optimum conditions are discussed and the method is applied to the analysis of copper in brass alloys.

t001. IV. Analysis of various samples in which copper was determined (Values given as percentages)

     

110.

Information theory in analytical chemistry: basic terms, definitions and interpretations. Arbeitskreis "Automation in der Analyse"     

Malissa H  Rendl J  Marr IL 《Talanta》1975,22(7):597-600

The most important terms in information theory (information, character, code, message and signal) are defined and interpreted with reference to automation in analytical chemistry. The aim of this communication and the earlier one dealing with systems theory, is to facilitate communication and understanding between all specialists working on or with automated systems for analysis.     

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Constituents	Thorn Smith # 30	Thorn Smith # 54	NBS # 37E	NBS # 63C
Cu present	59.30	84.04	69.61	80.48
Zn	37.81	1.452	27.85	0.093
Pb	0.1	8.590	1.00	9.35
Sn	Trace	5.737	1.00	9.03
Sb				0.52
Ni	Trace		0.53	0.32
P				0.145
S				0.060
As				0.023
Fe	1.22		0.004	0.0013
Al	1.15
Mn	0.35
Cu found	59.09	83.64	69.68a	80.54a	aAverage of 3 determinations.

Information theory in analytical chemistry: basic terms, definitions and interpretations. Arbeitskreis "Automation in der Analyse"

The most important terms in information theory (information, character, code, message and signal) are defined and interpreted with reference to automation in analytical chemistry. The aim of this communication and the earlier one dealing with systems theory, is to facilitate communication and understanding between all specialists working on or with automated systems for analysis.