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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.
994.
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.
A. I. Gerko 《Mathematical Notes》2000,67(6):707-717
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.
Jacek G. Sośnicki 《Monatshefte für Chemie / Chemical Monthly》2000,131(5):475-486
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.
Zoran IVKOVIC 《数学年刊B辑(英文版)》2000,21(1):109-114
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
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