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921.
A novel surface energy-based model is developed to examine more precisely vibrations of current-carrying double-nanowire-systems immersed in a longitudinal magnetic field. Using Biot-Savart and Lorentz laws, a more refined version of interwire interactional magnetic forces is presented. By employing Rayleigh beam theory, the equations of motion are derived. In fact, these are coupled integro-differential equations which are more accurate with respect to those of the previously developed models. For simply supported and clamped nanosystems, governing equations are analyzed via assumed mode method. The effects of interwire distance, slenderness ratio, electric current, magnetic field strength, and surface effect on the fundamental frequency are addressed carefully. The obtained results display the importance of exploiting the refined model for vibration analysis of nanosystems with low interwire distance, high electric current, and high magnetic field strength.  相似文献   
922.
ABSTRACT

The analysis of sedimentation or flotation (creaming) by detecting the transmission profile over the entire sample height in an analytical centrifuge (using a Stability Analyzer) is described and illustrated for a diverse range of practical dispersions and emulsions. It is also illustrated how to use extrapolated results to estimate dispersion shelf life stability for samples in a gravitational field. Formulation optimization, such as choosing appropriate surfactant levels, is also shown to be a practical application of such methods.  相似文献   
923.
Abstract: This article presents a review of the published articles related to the novel application of spectroscopy and microscopy methods in paint and coatings quality evaluation. Traditional and simple techniques have been used in paint and coating industry for many years and proven to be effective. However, the paint and coating industry faces new formulations with nontraditional applications. Therefore, the industry needs to adjust itself with the current sophisticated production and testing methods. There are a number of modern microscopy and spectroscopy techniques that can be utilized in the paint and coating industry for a better understanding of the product quality and/or application performance. This, in particular, is highly applicable in modern and nontraditional applications such as nanotechnology and smart coatings. Though importance of spectroscopy and microscopy methods is being increasingly recognized in the industry, there is no current comprehensive review available to highlight the need for novel application of these techniques in surface coatings evaluations.  相似文献   
924.
925.
The positively charged ions of palladium particles are obtained by reducing the solution containing metallic ions in the presence of PDDA (poly-diallyldimethylammonium chloride) medium. The nascent palladium particles are dispersed evenly on the surface of the perfluorosulfonate proton-conducting electrolyte membrane and bonded firmly to the activation center of the membrane. The mechanical strength of membrane is greatly enhanced by surface modification. And the methanol diffusion coefficients of the modified membrane are decreased prominently by the deposition of palladium particles on the surface, which serves as a natural barrier for methanol crossing.  相似文献   
926.
Attention is drawn to challenges facing the structure determination of compound surfaces of growing complexity. Besides the questions of large unit cells and disorder, and of many independent atoms in the unit cells, one must address the determination of composition, compositional disorder and simultaneously coexisting structures. Of special concern is the issue of stability of complex and compound surfaces, and the resulting concerns about experimental surface preparation and reproducibility.  相似文献   
927.
928.
Ionic liquids with herbicidal anions (named herbicidal ionic liquids—HILs) were synthesized and characterized. The combination of two active chemicals as the [cation][anion] form in a single moiety reduced the number of additional chemicals required per application. HILs ([cation][MCPA]) exhibited higher biological activity than currently used salts of MCPA, and involved pesticides of a multidirectional activity ([plant growth regulator][MCPA]). Acute toxicity of HILs could be controlled by appropriate selection of cation type. These salts had chemical and thermal stability, and showed substantially lower water solubility than starting herbicides, thus reducing soil and groundwater mobility.  相似文献   
929.
1. INTRODUCTION Bioreactors using membranes as substrates of cell cultures have become widely used for hybrid liver support systems [1]. For enhancing and prolonging the metabolism of the bioreactors, cytocompatible membranes are necessary because the cell culture is closely affected by the substrate surface. Surface factors considered to be important in cell culture are the concentration of ionic groups, the nature of polar and non-polar groups and the hydrophilic-hydrophobic balance [2].…  相似文献   
930.
The effect of different surface morphologies obtained by anisotropic etching on the light trapping and short circuit current of single crystalline silicon solar cells was investigated. The anisotropic texturing of a (1 0 0) silicon surface was performed using potassium hydroxide (KOH) solution and/or tetramethylammonium hydroxide (TMAH) solution including isopropyl alcohol (IPA) additive or tertiary butyl alcohol (TBA) additive. Texturing in TMAH solution formed smaller pyramids on the textured surface compared with texturing in KOH solution. Although the textured samples showed similar reflectances (except in the case of the TBA additive), they showed different short circuit currents. Texturing in KOH/TMAH solution led to a 9.6% increase in short circuit current compared with texturing in KOH/IPA solution, a typical etchant in commercial processes. Based on these results, the reflectivity has no simple proportionality relationship to the short circuit current, and the short circuit current of silicon solar cells should be the criterion used in evaluating texturing effects on reducing reflectance and forming a sound junction with high collection efficiency.  相似文献   
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