第二类四阶变分不等式解的存在唯一性

本文考虑弹性力学平板理论中的单侧稳定问题,讨论了重调和方程边值问题及第二类四阶变分不等式,并证明它们的等价性,从而可以把高阶偏微分方程转化为相应的变分不等式加以解决,同时也为求解重调和方程提供了更多的方法和理论依据。并且最后给出了该类变分不等式解的存在唯一性的证明。     

低压铸造充型动力学的高速摄影观察

利用高速摄影和影片运动分析技术,在透明模型上对低压铸造充型过程进行了实时观察和运动分析。结果表明:低压铸造充型的动力学特征可用二阶非线性微分方程描述。     

同心圆环型场发射阵列阴极的粒子模拟

 模拟了同心圆环型场发射阵列阴极的特性。采用时域有限差分法计算了电场，利用Fowler-Nordheim方程计算锥尖处的发射电流，利用Lorentz方程计算了电子的运动轨迹。得到了微阴极电子的运动轨迹、相空间图以及电子束的发散度、亮度等，结果表明该结构能形成良好的聚焦电子束。     

Critical thermodynamic analysis of differential scanning calorimetry for studying chemical kinetics

A critical thermodynamic analysis of differential thermal calorimetry is reported herein to gain further insight into the phenomena leading to the reported differences between kinetic parameters extracted from isothermal DSC methods and those from dynamic DSC methods. The sources have been identified for the variations observed in the total heat of reaction as a function of the heating rate in dynamic DSC experiments. The analysis clearly indicates that these variations are, in fact, to be anticipated. The relationships necessary for extracting kinetic data from both isothermal and dynamic experiments are derived rigorously by resorting to classical thermodynamics. This work was supported by the Cooperative State Research Service, U.S. Department of Agriculture, under Agreement No. 92-37500-7911.     

Almost periodic solutions for nonlinear duffing equations

The main purpose of this paper is to investigate the existence of almost periodic solutions for the Duffing differential equation. By combining the theory of exponential dichotomies with Liapunov functions, we obtain an intersting result on the existence of almost periodic solutions. This work is supported by NSF of China, No.19401013     

Multinomial convolution polynomials

In [9] Knuth shows how to derive the convolution formulas of Hagen, Rothe and Abel from Vandermonde's convolution and the binomial theorem for integer exponents. In the present paper, we shall first present a short and elementary proof of the multi-extension of the above convolution formulas, due to Raney and Mohanty. In the second part we shall present a multi-version of Knuth's approach to convolution polynomials and derive another short proof of the above formulas.     

Difference in moments of inertia and paring interaction strength in superdeformed nuclei

The difference in the bandhead moments of inertia between the superdeformed (SD) band¹⁹⁴Hg(1) and the two-quasiparticle SD bands¹⁹⁴Hg(2, 3) was investigated using the particle-number-conserving treatment for the cranked shell model Hamiltonian. and the pairing interaction strength in SD nuclei is estimated to be much weaker than that in normally deformed nuclei.     

Indirect determination of bilirubin by linear sweep polarography

Summary A polarographic method for the determination of bilirubin is described: In hydroquinone-sodium phosphate buffer (pH 11.2) medium, bilirubin can be rapidly oxidized to a green product, which causes a sensitive polarographic wave at –0.83 V (vs. SCE); the peak current of the wave is linear with the bilirubin concentration over a range of 3×10^–7 to 5×10^–6 mol/l. It has also been found to be more stable than that produced by bilirubin; in general, it can remain unchanged for about 1 h at room temperature and exposure to air. This overcomes the instability of bilirubin for its direct assay to a certain extent. If a small amount of EDTA is added to the solution, the stability of the wave can be further improved. In addition, the characteristics of the wave have been investigated and it has been confirmed to be an adsorptive catalytic wave. The chemical reaction mechanism is discussed and the green product is confirmed to be biliverdin.     

THE GENERAL SCHEME OF THE GENERALIZED WRONSKIAN TECHNIQUE

The general scheme of the generalized Wronskian technique ms given and is applied tofour energy-dependent potential's eigenvalue problems to generate four classes of nonlinearevolution equations solvable by the inverse spectral transform.