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991.
Tae Oan Ahn Jung Ho Kim Han Mo Jeong Sang Won Lee Lee Soon Park 《Journal of Polymer Science.Polymer Physics》1994,32(1):21-28
The compatibilizing effect of polyarylate-polystyrene (PAR-PS) block copolymer prepared from macroazo initiator was examined in polyarylate/polystyrene blends from the view-points of morphology, density, and thermal, mechanical, and rheological properties. PARPS block copolymer enhanced the mutual dissolution of the homopolymers. Reduced dispersed-domain size and increased density showed the efficiency of the block copolymer as a compatibilizing agent. Results from mechanical and rheological properties could also be explained by the compatibilizing effect of PAR-PS block copolymer in the blends. © 1994 John Wiley & Sons, Inc. 相似文献
992.
993.
994.
Han Shifang 《ournal of non Newtonian Fluid Mechanics》1984,15(2):181-197
The theory of nearly-extensional flow is developed to study the stability of extensional flow. For such flows a simple constitutive equation is derived for slightly disturbed extensional flow when a ‘short memory’ assumption is admissible.Following Minoshima and White and utilizing the constitutive equation obtained, a stability analysis for non-Newtonian fluid sheets is presented. The theoretical analysis presented is specific for an integral consitutive equation. The influence of the fluid elasticity on the stability behaviour is investigated. It is shown that the fluid sheet stability depends upon λk, where λ is the relaxation time and K is the elongation rate. 相似文献
995.
本文综合约20个 YBa2Cu3O7-4的元素替代体系的实验结果,发现:正交晶体结构、氧含量、铜的氧化价态,以及金属-半导体(绝缘体)相变都只是决定Tc的表观因素;存在着CuO2平面外和CuO2平面内两类元素替代效应.提出:高温超导体的迁移载流子浓度和CuO2平面内铜原子之间的动态、短程反铁磁关联程度是决定Tc的两个内禀因素.基于Bi系超导体中有关元素替代效应的实验事实,进一步提出上述结论对各种类型的高温氧化物超导体具有普遍性. 相似文献
996.
997.
Dong Han Kim 《Journal of heterocyclic chemistry》1981,18(4):855-856
The treatment of N-(2-hydroxyphenyl)anthranilic acids with cyanogen bromide in the presence of triethylamine gave dibenz[b,e][1,4]oxazepin-11-(5H)ones in good yields. 相似文献
998.
Jack Gelfand Muhammad Zughul Herschel Rabitz C.J. Han 《Journal of Quantitative Spectroscopy & Radiative Transfer》1981,26(4):303-305
We have measured the absorption intesities for a number of rotation-vibration lines in the 4-0 through 7-0 overtone bands of HCl utilizing a Fourier transform spectrometer and a 409.6 m path length White cell. Individual line strengths, band strengths, dipole matrix elements, and Herman-Wallis factors are presented. 相似文献
999.
Starting from simple topological arguments due to Dirac on the classical rotational properties of extended rigid bodies, we abstract the concept of a finite-size spinor (FSS). The FSS is a concept distinct from both point spinors (e.g., electrons) and composite spinors (e.g., nuclei), and suggests a new model for baryons. The FSS offers a natural explanation of threeness for the quarks, excludes the existence of free quarks, denies the operational definition of quark spin statistics, and, moreover, leads to the dual model of hadronic interactions.Research supported in part by the National Science Foundation, the Army Research Office (Durham), and the U.S. Atomic Energy Commission. 相似文献
1000.
Chien-Pai Han 《Annals of the Institute of Statistical Mathematics》1973,25(1):335-344
Summary In estimating the mean μ
y
of one variable in a bivariate normal distribution, the experimenter can use the other variable,x, as an auxiliary variable to increase precision. In particular, if μ
x
is known, he can use the regression estimator. When μ
x
is unknown, a preliminary test can be performed and the estimator will be made to depend on the result of the preliminary
test. The bias and mean square error of the preliminary test estimator are obtained and the relative efficiency is are discussed. 相似文献