Applicability Range of Stoneys Formula and Modified Formulas for a Film/Substrate Bilayer

In addition to the layer thickness and effective Young’s modulus, the impact of the kinematic assumptions, interfacial condition, in-plane force, boundary conditions, and structure dimensions on the curvature of a film/substrate bilayer is examined. Different models for the analysis of the bilayer curvature are compared. It is demonstrated in our model that the assumption of a uniform curvature is valid only if there is no in-plane force. The effects of boundary conditions and structure dimensions, which are not-fully-included in previous models are shown to be significant. Three different approaches for deriving the curvature of a film/substrate bilayer are presented, compared, and analyzed. A more comprehensive study of the conditions regarding the applicability of Stoney’s formula and modified formulas is presented.

Extended Stoney'S Formula For A Film-Substrate Bilayer With The Effect Of Interfacial Slip

The curvature-stress relation is studied for a film-substrate bilayer with the effect of interfacial slip and compared with that of an ideal interface without interfacial slip. The interfacial slip together with the dimensions, elastic and interfacial properties of the film and substrate layers can cause a significant deviation of curvature-stress relation from that with an ideal interface. The interfacial slip also results in the so-called free edge effect that the stress, constraint force, and curvature vary dramatically around the free edges. The constant curvature as predicted by Stoney's formula and the Timoshenko model of an ideal interface is no longer valid for a bilayer with a nonideal interface. The models with the assumption of an ideal interface can also lead to an erroneous evaluation on the true stress state inside a bilayer with a nonideal interface. The extended Stoney's formula incorporating the effects of both the layer dimensions and interfacial slip is presented.

Modified formula of Malus' law for Glan-Taylor polarizing prisms

A simple three-axis model has been developed, which has been successfully applied to the analysis of the light transmittance in spatial incident angle and the simulation of modified formula of Malus' law for Glan-Taylor prisms. Our results indicate that the fluctuations on the cosine squared curve are due to specific misalignments between the axis of the optical system, the optical axis of the prism and the mechanical axis (rotation axis) of prism, which results in the fact that different initial relative location of the to-be-measured-prism in the testing system corresponds to different shape of Malus' law curve. Methods to get absolutely smooth curve are proposed. This analysis is available for other kinds of Glan-type prisms. (C) 2004 Elsevier B.V. All rights reserved.

Landauer-Buttiker formula for time-dependent transport through resonant-tunneling structures: A nonequilibrium Green's function approach

A nonequilibrium Green's-function formalism is employed to study the time-dependent transport through resonant-tunneling structures. With this formalism, we derive a time-dependent Landauer-Buttiker formula that guarantees current conservation and gauge invariance. Furthermore, we apply the formula to calculate the response behaviors of the resonant-tunneling structures in the presence of rectangular-pulse and harmonic-modulation fields. The results show that the displacement current plays the role of retarding the tunneling current.

Hydrogen-Bonding Recognition-Induced Color Change of Gold Nanoparticles for Visual Detection of Melamine in Raw Milk and Infant Formula

The color change induced by triple hydrogen-bonding recognition between melamine and a cyanuric acid derivative grafted on the surface of gold nanoparticles can be used for reliable detection of melamine. Since such a color change can be readily seen by the naked eye, the method enables on-site and real-time detection of melamine in raw milk and infant formula even at a concentration as low as 2.5 ppb without the aid of any advanced instruments.

Calculation formula and synthesis for controlling the composition of hydroxy - Terminated butadiene acrylonitrile cooligomer

In preparing copolymer of the same composition by batch process in two - component copolymerization it is necessary to keep the monomer ratio constant by replenishing the fraction of the more reactive monomer. In this paper a calculation method for monomer feeding is derived, which iscapable of controlling the composition of cooligomer during the course of reaction. Some cooligomers of acrylonitrile and butadiene with relatively the same compositions have been prepared using the replenishing method. The method would be useful for other two - component copolymerization ion process.

PRINCIPLES FOR STRUCTURE GENERATION OF ORGANIC ISOMERS FROM MOLECULAR FORMULA

An expert system for the elucidation of the structure of organic compounds (ESESOC) has been developed. The heart of the ESESOC is formed by the structure generator as an integral part, which receives the specific type of information (molecular formula, s