Li adsorption on a Fullerene–Single wall carbon nanotube hybrid system: Density functional theory approach

In this study, we investigate Li adsorption mechanisms on the C₆₀-SWCNT hybrid system using density functional theory. It is found that the Li adsorption energy of the C₆₀-SWCNT hybrid system is increased in comparison to that of the pure SWCNT. The Li adsorption energy ranges from −1.917 eV to −2.642 eV for the single-Li adsorbed system and from −2.351 eV to −2.636 eV for the double-Li adsorbed system. It is also found that the adsorption energy becomes similar at most positions throughout the structure. In addition, the Li adsorption energy of 31-Li system is calculated to be −1.863 eV, which is significantly lower than the Li–Li binding energy (−1.030 eV). These results infer that Li atoms will be adsorbed on the space 1) between C₆₀ and C₆₀; 2) between SWCNT and C₆₀; 3) the rest of the space (e.g. between SWCNTs), rather than form Li clusters. As more Li atoms are adsorbed onto the C₆₀-SWCNT hybrid system due to such improved Li adsorption capability, the metallic character of the system is enhanced, which is confirmed via the band structure and electronic density of states.     

Phenolics: Nonclassical Routes to Solid and Liquid Binders

A nonconventional route for the manufacture of liquid or solid, one-step phenolic resins is discussed in this paper. Base-catalyzed condensation occurs in dispersed particles suspended in water as the continuous phase. Protective colloid type and concentration are major factors in determining particle size and, therefore, the ability to obtain either nonsettling dispersions or particulate solids that can be recovered and handled as powders. The technology is applicable to a variety of phenolic and aldehydic starting materials. In contrast to conventional manufacturing procedures, the current technology affords efficient process control and great latitude in selection of molecular weight, molecular weight distribution, and functionality.     

共振辐射的理论研究——Holstein方程的解

解决介质中共振辐射的关键问题是求解Holstein方程。本文直接利用算符运算将方程积分,给出了激发态粒子集居数的含无限项的级数表达式。基于对这个级数高阶系数的极限行为的研究,成功地克服了无穷项求和的困难,整理出一个在任意给定精度下都只含有限项的解式,由它可以计算出任何时刻的结果。 关键词：     

A full Eulerian finite difference approach for solving fluid–structure coupling problems

A new simulation method for solving fluid–structure coupling problems has been developed. All the basic equations are numerically solved on a fixed Cartesian grid using a finite difference scheme. A volume-of-fluid formulation [Hirt, Nichols, J. Comput. Phys. 39 (1981) 201], which has been widely used for multiphase flow simulations, is applied to describing the multi-component geometry. The temporal change in the solid deformation is described in the Eulerian frame by updating a left Cauchy-Green deformation tensor, which is used to express constitutive equations for nonlinear Mooney–Rivlin materials. In this paper, various verifications and validations of the present full Eulerian method, which solves the fluid and solid motions on a fixed grid, are demonstrated, and the numerical accuracy involved in the fluid–structure coupling problems is examined.     

Revisit to the THINC scheme: A simple algebraic VOF algorithm

This short note presents an improved multi-dimensional algebraic VOF method to capture moving interfaces. The interface jump in the THINC (tangent of hyperbola for INterface capturing) scheme is adaptively scaled to a proper thickness according to the interface orientation. The numerical accuracy in computing multi-dimensional moving interfaces is significantly improved. Without any geometrical reconstruction, the proposed method is extremely simple and easy to use, and its numerical accuracy is superior to other existing methods of its kind and comparable to the conventional PLIC (piecewise linear interface calculation) type VOF schemes.     

The Previously Unclassified Smectic Phases of Bis-(4′-n-Heptyloxybenzylidene)-1, 4–Phenylenediamine (HEPTOBPD)

Re-examination of the bis-(4′-n-alkoxy-benzylidene)-1,4–phenylenediamines, particularly the heptyloxy homologue, by optical microscopy and differential scanning calorimetry has confirmed the existence of two hitherto unclassified smectic phases, which are now assigned the code letters J and K (S_J andS_k     

High order multi-moment constrained finite volume method. Part I: Basic formulation

A new high-order finite volume method based on local reconstruction is presented in this paper. The method, so-called the multi-moment constrained finite volume (MCV) method, uses the point values defined within single cell at equally spaced points as the model variables (or unknowns). The time evolution equations used to update the unknowns are derived from a set of constraint conditions imposed on multi kinds of moments, i.e. the cell-averaged value and the point-wise value of the state variable and its derivatives. The finite volume constraint on the cell-average guarantees the numerical conservativeness of the method. Most constraint conditions are imposed on the cell boundaries, where the numerical flux and its derivatives are solved as general Riemann problems. A multi-moment constrained Lagrange interpolation reconstruction for the demanded order of accuracy is constructed over single cell and converts the evolution equations of the moments to those of the unknowns. The presented method provides a general framework to construct efficient schemes of high orders. The basic formulations for hyperbolic conservation laws in 1- and 2D structured grids are detailed with the numerical results of widely used benchmark tests.     

Growth and characterization of ZnSe/CdSe/ZnSe quantum dots fabricated by using an alternate molecular beam supplying method

ZnSe/CdSe/ZnSe structures inserted CdSe thin layer are fabricated using an alternate molecular beam supply (ALS). Examining the PL peak energy dependence on beam irradiation time in ALS cycle, we studied the initial stage of CdSe growth. When CdSe below the critical thickness is supplied on ZnSe grown on GaAs (1 0 0), two kinds of 2D islands (platelets) appear. We confirmed the alloying of 2D-CdSe islands and 3D-CdSe islands (dots) is prominent under Cd beam irradiation in ALS growth.