球壳的风型荷载屈曲

应用精确的球壳屈曲分支方程和Galerkin法,研究固定夹支半球壳承受风型荷载时的稳定性,确立了接近分支点变形的屈曲模态,所得屈曲临界值为科学设计提供了依据。     

薄壳问题的三维虚边界元解法

直接从三维弹性力学微分方程出发,依据三维的Kelvin解,应用最小二乘法建立了三维虚边界元法解薄壳问题的一般方法。本方法的显著优点是：不论求解何种壳体问题,方法的思想是不变的,均以三维的Kelvin解来建立方程,而勿需对不同几何形状的壳体采用不同的基本解。文中给出了数值算例,以作为本方法的应用。本文方法与边界元直接法相比,优点在于无需处理奇异积分,且系数阵是对称的;再者,本文方法思想简单,程序实现容易。     

带旋转自由度C^0类任意四边形板（壳）单元

基于Ｒｅｉｓｓｎｅｒ－Ｍｉｎｄｉｌｉｎ板弯曲理论和Ｖｏｎ－Ｋａｒｍａｎ大挠度理论,采用单元域内和边界位移插值一致性的概念,将四节点等参弯曲单元与Ａｌｌｍａｎ膜变形二次插值模式相结合,对层合板壳的大挠度分析提供了一种实用的带旋转自由度的四节点Ｃ＾０类板单元。大量算例表明：该单元对板壳结构的线性强度、稳定性和后屈曲分析都表现出良好的收敛性和足够的工程精度。     

邻苯二甲醛柱前衍生反相高效液相色谱法测定珍珠母中氨基酸

以邻苯二甲醛和β－巯基乙醇为衍生化试剂,柱前衍生,ＯＤＳ（Ｃ１８）柱分离,ｐＨ５．６乙酸盐缓冲液、甲醇二元梯度洗脱,荧光检测,在３２ｍｉｎ内分离测定了珍珠母中８种氨基酸的含量。在一定浓度范围内,氨基酸的峰面积与其浓度呈良好的线性关系,相关系数在０．９９８４～０．９９９４之间。对于８种氨基酸,标准加入回收率在９５％～１０５％之间。     

Methods of finite element analysis of arbitrary buckling forms of sandwich plates and shells

Two statements of the problem of arbitrary buckling forms (BFs) (including synphasic, antiphasic, mixed flexural, flexural-shear, and shear forms in the tangential directions) of general-form sandwich shells and two schemes of its solution by the FEM are given. The first of the schemes is based on the use of refined linear equations for determination of the precritical stress-strain state and linearized equations of neutral equilibrium with all parametric addends necessary to determine the critical loads and reveal the possible BFs. The second one uses the general geometrically nonlinear relations of elasticity theory for investigation of the whole deformation process up to buckling in terms of a modified incremental (stepwise) statement of the problem. Examples of solution of particular problems are given.Center for Study of Dynamics and Stability, Tupolev Kazan' State Technical University, Kazan', Tatarstan, Russia. Translated from Mekhanika Kompozitnykh Materialov, Vol. 36, No. 4, pp. 473–486, July–August, 2000.     

Shape coexistence in 188Pb

The shape coexistence in 188Pb is investigated in terms of the projected shell model. Analyzing the experimental data with the calculated results, it is shown that the three shapes, sphere, oblate and prolate, coexist with each other in the low-lying excited states. The prolate band exhibits a mixture between two kinds of multi-particle-hole configuration. The mixing is discussed and the mixing coefficients are given, meaning the νi13/2 pair alignment happens gradually in this case. The oblate (πh9/22p-2h) band structure is predicted and the 2+ prolate state is in the range of 804-880 keV.     

Synthesis of PEDOT Nanoparticles and Vesicles by Dispersion Polymerization in Alcoholic Media

Summary: The synthesis of PEDOT nanoparticles and vesicles by dispersion polymerization in a methanol/water mixture (3/2, v/v) is reported, using either ammonium persulfate or iron(III) p‐toluenesulfonate as oxidants and α‐EDOT‐PEO as a reactive stabilizer. The influence of the oxidant as well as the α‐EDOT‐PEO molar mass and concentration on the core‐shell particle morphology and conductivity properties have been investigated. PEDOT particles with conductivities up to 1.5 × 10⁻² S · cm⁻¹ have been obtained in high yield.

TEM image of PEDOT vesicles prepared using PEO‐based stabilizers of 25 000 g · mol⁻¹ in water/methanol mixture (2:3 v/v) at room temperature using ammonium persulfate as an oxidant.     

Discrete gap breathers in a two-dimensional diatomic face-centered square lattice

In this paper we study the existence and stability of two-dimensional discrete gap breathers in a two-dimensional diatomic face-centered square lattice consisting of alternating light and heavy atoms, with on-site potential and coupling potential. This study is focused on two-dimensional breathers with their frequency in the gap that separates the acoustic and optical bands of the phonon spectrum. We demonstrate the possibility of the existence of two-dimensional gap breathers by using a numerical method. Six types of two-dimensional gap breathers are obtained, i.e., symmetric, mirror-symmetric and asymmetric, whether the center of the breather is on a light or a heavy atom. The difference between one-dimensional discrete gap breathers and two-dimensional discrete gap breathers is also discussed. We use Aubry's theory to analyze the stability of discrete gap breathers in the two-dimensional diatomic face-centered square lattice.     

Exponential convergence rate in entropy

The exponential convergence rate in entroy is studied for symmetric forms, with a special attention to the Markov chain with a state space having two points only. Some upper and lower bounds of the rate are obtained and five examples with precise or qualitatively exact estimates are presented.      

Multilayer Shell Walls with Versatile Electron Transfer Properties

Core‐shell microparticles with functional multilayer shell walls consisting layers of naphthalene‐labeled polyanion ANp10 and polyviologen (PV) were fabricated through layer‐by‐layer (LbL) self‐assembly. Fluorescence emission from the naphthyl group in the ANp10 layer was found to be quenched by the viologen group in the PV layer regardless in inner or outer layer. This quenching was attributed to electron transfer from the excited naphthyl donor to the viologen acceptor. The quenching efficiency was simply tuned by changing numbers of the ALG/CHI bilayer spacer and PV layer. The resulting core‐shell microparticles will be served as a novel light‐harvesting antenna system.