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991.
O. Perat J. M. Dorkel E. Scheid P. Temple Boyer Y. S. Chung A. Peyre-Lavigne M. Zecri P. Tounsi 《Microelectronics Reliability》2002,42(7):1053-1058
Reliability of thermomechanical simulations is critically linked to the accuracy of the mechanical properties that govern the behaviour of structure, like Young's modulus (E) and coefficient of thermal expansion (CTE). For many cases, the values found in literatures are dealing with bulk properties without detailed information on temperature effects. To address such issues, it is necessary to measure the materials parameters as a function of temperature. The measurement of CTE is usually accomplished by evaluating the thermal deflections of a subjected material layer deposited on a substrate, providing that E is known at a specific temperature of experiment. A bilayer method, based on theory of elasticity, is proposed to determine both E and CTE for a given temperature with a good resolution. This paper presents the theoretical analysis, the design and process of the microsystem test structures, and the main calculation results. 相似文献
992.
对于今天的织物,易护理性是一项基本要求。然而,理想的易护理效果不可能仅通过Tencel纤维本身的性能来获得,合适的织物组织结构、恰当的前处理,以及最佳的高级整理加工可以提高Tencel织物的易护理性能,并超过其他纤维素纤维。关于织物组织结构的影响已经在其他杂志上有过讨论。本文将说明如何采用不同的前处理、后整理加工,获得高档最终产品的方法。 相似文献
993.
G.D. Wignall R.W. Hendricks W.C. Koehler J.S. Lin M.P. Wai E.L. Thomas R.S. Stein 《Polymer》1981,22(7):886-889
A series of small angle neutron scattering measurements on blends of normal polystyrene (PSH) and labelled (deuterated) polystyrene (PSD) have been made with concentrations of PSD from 5 to 50 mol %. It is shown that the single chain form factor of the polymer in bulk can be obtained from a single concentration measurement for any concentration of labelled molecules, providing the molecular weights of the parent and labelled molecules are the same and the molecular weight distributions are narrow. 相似文献
994.
Rapeseed protein concentrate (RC), prepared with 2% hexameta-phosphate, was tested for its functionality and performance in some foods. The RC had good nitrogen solubility, fat absorption, emulsification, and whipping capacities but poor water absorption and gelling properties. It increased the emulsion stability, and protein but lowered the fat content of wieners. It also increased the cooking yield, reduced the shrinkage and tenderized meat patties. Results were similar to soybean isolate except for the poorer color and flavor. The cooking yield of RC supplemented wieners was less than the all-meat control and soybean-supplemented wieners. A 9% RC dispersion mixed with an equal volume of eggwhite produced a meringue of comparable stability and texture to that of eggwhite alone. 相似文献
995.
The properties of a spinel copper cobaltite obtained by thermal decomposition of mixed nitrates of both metals at 350°C and normal pressure are described. It has been shown that the maximum copper content (x) in the spinel CuxCo3?xO4 does not exceed 0.9. When the copper amount in the initial mixture is higher a second phase CuO is formed. The copper ions are distributed over the A- and the B-sites of the spinel lattice, i.e. the spinel is partially inverted. Such a model explains well the data obtained about the lattice parameter, IR-absorption and the magnetic susceptibility of the samples with different x. 相似文献
996.
A historical review of licensing among industrial/organizational (I/O) psychologists demonstrates that the American Psychological Association (APA) policy on such licensing is inconsistent. Arguments for and against licensure for this group are presented. Job analysis and APA data are drawn upon to show that few I/O activities may pose the personal risk that would seem to require the protection of a license. Alternatives are discussed for changes in present APA policy and state licensing requirements. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
Dynamic mechanical properties have been investigated for interpenetrating-network systems based on polyol-cured polyurethanes (PU) and 2 to 1 n-butyl acrylate-n-butyl methacrylate (Ac) networks. The systems were formed simultaneously (SIN) from all of the precursors and reactants for both networks in the same vessel, and sequentially (SIPN) by swelling a precured PU with the reactants that will form the Ac network. If the Ac network is formed after gelation of the PU, the IPNs are transparent and appear to have single T (tan δmax) between those of the homonetworks; visible-phase separation occurs if the Ac is intentionally polymerized prior to PU gelation. Damping curves were lower and broader and the T (tan δmax) and rubber moduli were higher for the SIN than for the SIPN systems. Up to 65 percent Ac, the T (tan δmax) data for both SIN and SIPN fit the Gordon-Taylor equation if a T (tan δmax) for the Ac homonetwork 7°C higher than observed is used, suggesting a higher crosslink density for the Ac network under these conditions. The differences in properties of the SIN and SIPN are assumed to be dependent on sample homogeneity and upon the presence of a tin catalyst in the SIN preparation. This can result in limited Ac-network formation and consequent phase separation before PU gelation has occurred, and the catalyst may also increase the extent of interaction, such as grafting or hydrogen-bond formation between the networks. 相似文献
999.
Michael L. Mushet 《Information Systems Management》1991,8(3):21-26
For the past three decades, IS managers have been faced with the tasks of honing their craft, improving productivity, and serving as the keepers of information technology for the corporation. For the most part, they have done a commendable job. However, the rules of the game are changing. Old solutions are no longer extensible to current problems, and today's problems are unlike any faced in the past. This article takes a fresh look at what the top priorities for IS managers should be in the coming years. 相似文献
1000.
The survey focuses on algebraic-grammatical models of parallel processes, representation of knowledge about classes of algorithms in terms of a variety of production systems (structured design grammars), and program generation tools.Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 5–13, September–October, 1991. 相似文献