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991.
Microscopic study of polymorphism of a photographic coupler   总被引:1,自引:0,他引:1  
Polymorphism and polymorphic transformation of a photographic coupler have been examined using hot stage optical microscopy (HSOM). Two different polymorphs, metastable needle-like crystals and stable cubic-like crystals, were identified on heating. A solid-state transformation was found to occur from the metastable form to the stable form. Both polymorphs can precipitate from coupler solutions. The needle-like crystals appear in all cases examined; the cubic-like crystals precipitate only with higher concentrations and lower cooling rates. The solution-mediated transformation occurs in an organic solvent through dissolution of the metastable polymorph and growth of the stable polymorph. The growth rate of the stable polymorph is dependent on temperature as well as concentration. The activation energy of the growth is estimated for coupler solutions with different concentrations.  相似文献   
992.
IntroductionForseveralhundredyears,ithasbeenbothimportantanddifficultprojecttoconstructtheanalyticalsolutionsfornonlineardifferentialequations.Manymathematiciansandtheoreticalphysicistshavedonealotofwork[1~ 5 ].However,thereexistlotsofimportantandbeingofp…  相似文献   
993.
介绍一种可以用来测量曲面试件表面应分量(εz,εθ,εzθ)的激光光栅显微图像检测技术(IGM),它能实现从小应变到大应变全过程的高精度定量测量。我们将这一技术成功地应用在铁基形状记忆合金(FSMA)管接头的结构设计中,在这项研究中,首先在管接头结构表面制作了变形的载体-位相型干涉光栅,由结构表面产生的衍射光通宵我学系统后形成新的干涉光栅,我们利用数字图像系统接收了逆相变前后各自的干涉图像,采用带  相似文献   
994.
G. Emanuel  T.H. Yi 《Shock Waves》2000,10(2):113-117
A spatially and temporally local analysis is provided for unsteady, oblique shock waves, in which the flow is assumed to be two-dimensional or axisymmetric. Three unsteady parameters, in a laboratory frame, are viewed as the known independent variables. These are the upstream Mach number, the shock Mach number, and the angle of the shock relative to the instantaneous upstream velocity. Other steady and unsteady parameters, such as the velocity turn angles and downstream Mach numbers, are evaluated in closed form, in terms of these three quantities. Trends are assessed, and a sensitivity analysis is provided. It is suggested that the theory may find application in converting a shock capturing algorithm, at an early time during the computational process, into a shock fitting algorithm. Received 30 April 1999 / Accepted 29 November 1999  相似文献   
995.
Based on the microstructure-based constitutive model established in Part I, a detailed numerical investigation on the role of each microstructure parameter in the kinematical and kinetic evolution of polycrystalline SMA under axisymmetrical tension loading is performed. Some macroscopic constitutive features of stress-induced martensite transformation are discussed. The subject supported by the Research Grant Committee (RGC) of Hong Kong SAR, the National Natural Science Foundation of China and the Provincial Natural Science Foundation of Jiangxi Province of China  相似文献   
996.
In the paper methods from the theory of extensions of dynamical systems are used to studyβ-differential equations whose solutions possess the uniqueness property and depend continuously on the initial data and on the right-hand side of the equation. The Zhikov-Bronshtein theorems concerning asymptotically almost periodic solutions of ordinary differential equations are extended toβ-differential equations (in particular, to total differential equations). Along with asymptotic almost periodicity, we also consider asymptotic recurrence, weak asymptotic distality, and asymptotic distality. To the equations we associate dynamical systems generated by the space of the right-hand sides and the spaces of the solutions and of the initial data of solutions of the equation. Generally, the phase semigroups of the dynamical systems are not locally compact. Translated fromMatermaticheskie Zametki, Vol. 67, No. 6, pp. 837–851, June, 2000.  相似文献   
997.
Summary.  1-Acylmethylene-3,3-dimethyl-1,3-dihydroisobenzofurans were found to be useful precursors for pyrazole synthesis. In the reaction with hydrazine monohydrate they yielded 3-(2-(α-hydroxyisopropyl)-phenyl) substituted NH-pyrazoles, whereas using alkyl- or arylhydrazine gave access to 5-(2-(α-hydroxyisopropyl)-phenyl) substituted NR-pyrazoles with good regioselectivity. Treatment with orthophosphoric acid led to C,N-fused and C,C-fused pyrazoles, respectively. Received November 4, 1999. Accepted (revised) December 3, 1999  相似文献   
998.
ThispaperisanoutcomeofnumerousdiscusionsandexchangeofideaswithlatePredragPerunicic,whosedeepandprofoundmathematicalknowledgeandhumanvaluesgaveusaninspirationandmotivationtofinalizeourjointideas.1.Wereferto[3,4]forthenotionofspectralmultiplicitytheoryintheseparableHilbertspace.LetHbeacyclicHilbertspacewiththeresolutionoftheidentity{p(t)}ofthemaximalspectraltypelIP(dt)ll'~dt-ordinaryLebesguemeasure.Anon-anticipativelineartransformationsisdefinedbyVolterrakernelg(t,u),uSt,ajsf'g(t)u)p(du),t>0…  相似文献   
999.
求强非线性系统次谐共振解的MLP方法   总被引:10,自引:0,他引:10  
唐驾时 《应用数学和力学》2000,21(10):1039-1045
定义了一个新的参数变换α=α(ε,nω0/m,ω1),扩展了改进的LP方法的应用范围,使该方法能够求强非线性系统的次谐共振解.研究了Duffing方程的1/3亚谐和3次超谐共振解以及Vander Pol-Mathieu方程1/2亚谐共振解,这些例子说明近似解和数值解相当吻合.  相似文献   
1000.
本文利用矩阵行的初等变换 ,采用递推的方法 ,求出了有限域 k上 n次一般线性群 GLn(k)和 n次特殊线性群 SLn(k)的阶 .  相似文献   
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