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991.
在交换半环范畴中,研究赋值与序之间的相容性。通过引进赋值的半截口,这样一个事实被证明:半环的一个赋值具有一个半截口,只要该赋值的值幺半群是一个群。基于此事实,建立了如下主要结果:对于半环S的一个赋值v,v是S的一个实赋值当且仅当v与S的某个序相容。 相似文献
992.
在拓扑化学理论基础上,采用新型拓扑指数Tp1,Tp2和分子结构信息指示变量I对35个取代硝基苯类化合物的局部化学微环境进行了结构表征,并对其生物毒性进行了定量构效关系(QSAR)研究.实验结果表明,采用偏最小二乘回归法得到的拓扑模型相关系数R和标准偏差S分别为0.981 8和0.151 6,对35个取代硝基苯类化合物生物毒性实验值与计算值的相对平均误差仅为1.09%.留一检验法(LOO)交互检验测试结果显示,该模型具有良好稳定性和较强的预测能力. 相似文献
993.
By using o-mapping method, we discuss the topological structure of the self-duality solution in Jackiw-Pi model in terms of gauge potential decomposition. We set up relationship between Chern-Simons vortex solution and topological number, which is determined by Hopf index and Brouwer degree. We also give the quantization of flux in this case. Then, we study the angular momentum of the vortex, which can be expressed in terms of the flux. 相似文献
994.
M. R. Zhang X. Y. Jiang Y. L. Zhang L. Shi J. Zi J. Y. Zhou 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(3):269-278
We systematically investigate slowly moving matter-wave gap
soliton propagation in weak random optical lattices. With the weak
randomness, an effective-particle theory is constructed to show
that the motion of a gap soliton is similar to a particle moving
in random potentials. Based on the effective-particle theory, the
effects of the randomness on gap solitons are obtained and the
trajectories of gap solitons are well predicted. Moreover, the
general laws that describe the movement depending on the weak
randomness are obtained. We find that with an increase of the
random strength, the ensemble-average velocity reduces slowly and
the reflection probability becomes larger. The theoretical results
based on the effective-particle theory are confirmed by the
numerical simulations based on the Gross-Pitaevskii equation. 相似文献
995.
By making use of the decomposition of U(1) gauge potential theory and the C-mapping method we discuss a mixture of interacting neutral and charged Bose condensates, which is supposed being realized in the interior of neutron stars in the form of a coexistent neutron superfluid and protonic superconductor. We propose that this system possesses vortex lines and two classes of knotted solitons. The topological charge of the vortex lines are characterized by the Hopf indices and the Brower degrees of φ-mapping, and the knotted solitons are described by nontrivial Hopf invariant and the BF action respectively. 相似文献
996.
Understanding the physical significance and probing the global invariants characterizing quantum topological phases in extended systems is a main challenge in modern physics with major impact in different areas of science. Here, a quantum‐information‐inspired probing method is proposed where topological phase transitions are revealed by a non‐Markovianity quantifier. The idea is illustrated by considering the decoherence dynamics of an external read‐out qubit that probes a Su–Schrieffer–Heeger (SSH) chain with either pure dephasing or dissipative coupling. Qubit decoherence features and non‐Markovianity measure clearly signal the topological phase transition of the SSH chain. 相似文献
997.
998.
Topological insulators, a class of typical topological materials in both two dimensions and three dimensions,are insulating in bulk and metallic at surface. The spin-momentum locked surface states and peculiar transport properties exhibit promising potential applications on quantum devices, which generate extensive interest in the last decade. Dephasing is the process of the loss of phase coherence, which inevitably exists in a realistic sample. In this review, we focus on recent progress in dephasing effects on the topological insulators. In general, there are two types of dephasing processes: normal dephasing and spin dephasing. In two-dimensional topological insulators, the phenomenologically numerical investigation shows that the longitudinal resistance plateaus is robust against normal dephasing but fragile with spin dephasing. Several microscopic mechanisms of spin dephasing are then discussed. In three-dimensional topological insulators, the helical surface states exhibit a helical spin texture due to the spin-momentum locking mechanism. Thus, normal dephasing has close connection to spin dephasing in this case, and gives rise to anomalous “gap-like” feature. Dephasing effects on properties of helical surface states are investigated. 相似文献
999.
关于理想气体的宏观定义 总被引:4,自引:3,他引:4
讨论了理想气体的热力学方面的定义,说明:玻意耳定律,理论气体温标和焦耳定律是从宏观上界定理想气体的基本上属性和特征的三个必不可少的实验定律。 相似文献
1000.
重整热力学第二定律的理论体系 总被引:3,自引:4,他引:3
利用理想气体可逆过程的规律来替代热机,就得以了克劳修工和不等式,由此解决了熵、卡诺定理、绝对温标等问题。 相似文献