矩形毛细微槽中三角形区域接触线特性的研究

利用CCD和宽视场体视显微镜相结合的技术,拍摄了矩形毛细微槽内液体工质在三角形区域的润湿图像,并进行了图像处理,研究结果表明:随着热流密度的增加,三角形区域内的三相接触线向微槽底角收缩,导致三相接触线的长度减小,液膜厚度减小;随着微槽深度的增加,三角形区域的接触线长度减小;随着微槽宽度和倾斜角度的增加,三角形区域内的接触线长度增加,液膜厚度增加.     

Effects of controllable process factors on Al rear surface bumps in Si solar cells

High efficiency solar cells require good back surface field passivation and high back reflectance in the rear Al region. In module processes, wafer-based solar cell can break through stress during soldering uneven rear aluminum surfaces - a serious problem that affects throughput. This work examined rear surfaces with respect to controllable process factors such as ramping and cooling rates during rapid thermal processing, and the fineness of aluminum powder used in the screen-printed paste. A faster ramp up rate resulted in a uniform temperature gradient between the aluminum and silicon surfaces. As a results, the bumps on the aluminum surface were small and of high density. Fine aluminum metal powder in the paste for screen-printing contact points resulted in large distribution, high density bumps. Bumps formed during cooling in metallization, their sizes and densities were dependent the on uniformity of the aluminum and silicon liquid wetting of the silicon surface.     

Contact Classification of Linear Ordinary Differential Equations: I

It is known that a linear ordinary differential equation of order n3 can be transformed to the Laguerre–Forsyth form y ⁽ⁿ⁾= _i=3 ⁿ a _n–i (x)y ^(n–i) by a point transformation of variables. The classification of equations of this form in a neighborhood of a regular point up to a contact transformation is given.     

硅基稀土热扩散法初探

稀土元素在我国有丰富的贮量．近年来,稀土元素在各种新科技领域中得到不断的开发和利用．各类稀土功能材料在发光和光通信领域中正展现巨大的应用潜力［１］．稀土磁光薄膜材料是优良的记录介质;稀土Ｅｒ由于其特殊的电子结构,已用来制造掺铒光纤激光器和光纤放大器［２］;掺铒硅还可制造发光谱线单一的发光器件［３］,这为实现人们所期待的硅基光电集成提供了有益途径．此外,基于对掺铒硅荧光发射衰减时间的分析,可用于制造温度传感器［４］．因此,稀土在共价半导体材料如Ｓｉ、ＧａＡｓ中的行为研究日益受到重视．但这些工作主要…     

Contact Transformations and Local Reducibility of ODE to the Form y‴=0

Orbits of the ODE y=0 in corresponding jet bundles are investigated. Explicit relations for the right-hand side of an arbitrary 3-order ODE necessary and sufficient for the existence of a contact transformation reducing this equation locally to the form y=0 are obtained.     

Optical characteristics of uniaxial polyester films with the optical axis perpendicular to the surface

The functions of the main indices of refraction n(ν) and absorption κ(ν) of uniaxial thin polyethylene terephthalate films have been calculated by the experimental spectra of frustrated total reflection of s-and p-polarized radiation in the 700–760-cm⁻¹ range. The κ_o(ν) maximum falls at the the 727-cm⁻¹ frequency and the maximum of κ_e(ν) falls at the the 724-and 732-cm^{− 1} frequencies. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 756–759, November–December, 2005.     

Impact Oscillator with Hertz's Model of Contact

Dynamic properties of simple mechanical 1 DOF system containing soft stop is described and analyzed. The proposed general dynamical impact model respects the nonlinearity of the restoring contact force between solid bodies as function of deformation and velocity. It describes the real behavior of impacting system more exact than the piecewise linear model or the Kelvin–Voigt model and even model based on application of constant coefficient of restitution. Free and forced vibrations of system with Hertz's contact are investigated and domains of various types of impact motion, response curves and phase-plane trajectories are presented.     

Analytical solution to a mode of mixed elastohydrodynamic lubrication with mixed contact regimes: Part I. Without consideration of contact adhering layer in the inlet zone

In 2005, Zhang presented a Grubin-like inlet zone analysis to the isothermal line contact elastohydrodynamic lubrication under relatively heavy loads when the hydrodynamic film thickness in the Hertzian zone approaches zero and the EHL fluid is Newtonian [Zhang, Y.B. A justification of the load-carrying capacity of elastohydrodynamic lubrication film based on the Newtonian fluid model. Industrial Lubrication and Tribology, 2005, Vol. 57, pp. 224–232]. His results showed that in this EHL, when the rolling speed is lower than the characteristic rolling speed (U_ch =) 0.0372W^1.50/G, the Hertzian zone is in physical adsorbed layer boundary lubrication while the inlet zone is in conventional hydrodynamic lubrication. This mode of EHL represents a mode of mixed EHL with mixed contact regimes, where hydrodynamic films with different rheological behaviors occur in different areas of the contact. The present paper presents an analysis to this mode of mixed EHL by using the Grubin type method when the contact adhering layer in the inlet zone is neglected. Pressures, film thicknesses and load partition in the contact are obtained from this analysis. It is also found that the formula for the characteristic rolling speed U_ch = 0.0372W^1.50/G obtained by Zhang [Zhang, Y.B. A justification of the load-carrying capacity of elastohydrodynamic lubrication film based on the Newtonian fluid model. Industrial Lubrication and Tribology, 2005, Vol. 57, pp. 224–232] may be valid for the dimensionless load W > 1.0E−7, while it may be invalid for the dimensionless load W < 1.0E−8. In part II [Zhang, Y.B. Analytical solution to a mode of mixed elastohydrodynamic lubrication with mixed contact regimes: Part II. Considering the contact adhering layer effect in the inlet zone. Journal of Molecular Liquids, 2006, Vol. 117. (doi:10.1016/j.molliq.2006.04.007)] will be presented an analysis to other two modes of mixed EHL with mixed contact regimes for relatively heavy loads, low rolling speeds and Newtonian fluids, where the conventional hydrodynamic lubrication, physical adsorbed layer boundary lubrication and oxidized chemical layer boundary lubrication can simultaneously occur in the inlet zone while the oxidized chemical layer boundary lubrication or the fresh metal-oxidized chemical boundary layer dry contact occur in the Hertzian zone, considering the contact adhering layer effect in the inlet zone.     

3-Sasakian manifolds, 3-cosymplectic manifolds and Darboux theorem

We present a compared analysis of some properties of 3-Sasakian and 3-cosymplectic manifolds. We construct a canonical connection on an almost 3-contact metric manifold which generalises the Tanaka–Webster connection of a contact metric manifold and we use this connection to show that a 3-Sasakian manifold does not admit any Darboux-like coordinate system. Moreover, we prove that any 3-cosymplectic manifold is Ricci-flat and admits a Darboux coordinate system if and only if it is flat.     

Critical behavior of a two-species reaction-diffusion problem in 2D

In this work we study the critical behavior of a model that simulates the propagation of an epidemic process over a population. We simulate the model on two-dimensional finite lattices to determine the critical density of the diffusive population. A finite size scaling analysis is employed to determine the order parameter and correlation length critical exponents.