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141.
Arrangement transformation approach (ATA) for doing state-to-state quantum reactive scattering calculations of atom-diatom
systems is given. The state-to-state results of H + DH on ISTH potential energy surface are presented, and it can be deduced
from the results that the ATA method can be used for the system with more than three atoms.
Project supported by the National Natural Science Foundation of China (Grant No. 19774038) and Shandong Science Foundation
(Grant No. Y96A08012). 相似文献
142.
一个素变数的Diophantine不等式 总被引:3,自引:3,他引:0
设1<C<13/12.本文证明了存在N(C)>0使得对任意实数N>N(C),下面的不等式|++ -N|<N- )logsN有素数解p1,p2,p3,其中s=2(15). 相似文献
143.
Liu Xiyu 《数学学报(英文版)》1998,14(1):125-134
This paper deals with a class of nonlinear boundary value problems which appears in the study of models of flows through porous
media. Existence results of asymptotic bifurcation and continua are reported both for operator equations and for boundary
value problems.
This work is supported in part by NSF of Shandong Province and NNSF of China 相似文献
144.
本文研究亚纯函数f与f'具有两个公共值时的Frank问题,证明了若f与f'以0为CM公共值,以有穷非零复数b为IM公共值,则f=f'或f=2b/1-ce-2z,其中c为任一有穷非零复数. 相似文献
145.
WANGPEIGUANG FUXILINAND YUYUANHONG 《高校应用数学学报(英文版)》1998,13(4):397-402
In this paper, the higher order neutral differential equation with continuous distributed delay is concerned and the oscillatory criteria are given. 相似文献
146.
On sums of a prime and four prime squares in short intervals 总被引:1,自引:0,他引:1
Xian-Meng Meng 《Acta Mathematica Hungarica》2004,105(4):261-283
147.
148.
Pang Changci 《Annals of Differential Equations》2005,21(3):385-388
In this paper, we investigate the periodic boundary value problems for nonlinear first order functional differential equations. By establishing a new comparison result, criteria on the existence of maximal and minimal solutions are obtained. 相似文献
149.
Quasi-C-Ehresmann Semigroups and Their Subclasses 总被引:3,自引:0,他引:3
We introduce the concept of a quasi-C-Ehresmann semigroup. Some
special quasi-C-Ehresmann semigroups will be considered. We will
show that the quasi-C-Ehresmann semigroups are special
U-semiabundant semigroups and orthodox U-liberal semigroups,
which have been recently studied by several authors. Some
characterization theorems of this new class of semigroups are
obtained. Many results of quasi-C-semigroups in the literature
can be extended to quasi-C-Ehresmann Semigroups. 相似文献
150.
The objective of this research was to modify the crystal shape and size of poorly water-soluble drug ropivacaine, and to reveal the effects of polymeric additive and ultrasound on crystal nucleation and growth. Ropivacaine often grow as needle-like crystals extended along the a-axis and the shape was hardly controllable by altering solvent types and operating conditions for the crystallization process. We found that ropivacaine crystallized as block-like crystals when polyvinylpyrrolidone (PVP) was used. The control over crystal morphology by the additive was related to crystallization temperature, solute concentration, additive concentration, and molecular weight. SEM and AFM analyses were performed providing insights into crystal growth pattern and cavities on the surface induced by the polymeric additive. In ultrasound-assisted crystallization, the impacts of ultrasonic time, ultrasonic power, and additive concentration were investigated. The particles precipitated at extended ultrasonic time exhibited plate-like crystals with shorter aspect ratio. Combined use of polymeric additive and ultrasound led to rice-shaped crystals, which the average particle size was further decreased. The induction time measurement and single crystal growth experiments were carried out. The results suggested that PVP worked as strong nucleation and growth inhibitor. Molecular dynamics simulation was performed to explore the action mechanism of the polymer. The interaction energies between PVP and crystal faces were calculated, and mobility of the additive with different chain length in crystal-solution system was evaluated by mean square displacement. Based on the study, a possible mechanism for the morphological evolution of ropivacaine crystals assisted by PVP and ultrasound was proposed. 相似文献