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31.
《Physics letters. A》2020,384(28):126722
The supersymmetry-based semiclassical method (SWKB) is known to produce exact spectra for conventional shape invariant potentials. In this paper we prove that this exactness follows from their additive shape invariance. 相似文献
32.
本文利用红外光解离光谱研究了第三族金属氧化物离子对二氧化碳分子的转化机制. 研究表明,对于[ScO(CO2)n]+体系,在n≤4时,形成了溶剂化结构;在n=5时,形成了碳酸盐结构,实现了二氧化碳的转化. 对于[YO(CO2)n]+体系,需要4个二氧化碳分子就可以实现二氧化碳的转化. 而在[YO(CO2)n]+体系中,只发现了溶剂化结构,没有观察到碳酸盐结构. 理论计算表明,[YO(CO2)n]+体系拥有最小的溶剂化结构向碳酸盐结构转化能垒,[LaO(CO2)n]+体系拥有最大的溶剂化结构向碳酸盐结构转化能垒. 本文从分子水平揭示了不同金属氧化物离子对二氧化碳分子转化的影响规律. 相似文献
33.
Pingyu Zhu Qilin Zheng Shichuan Xue Chao Wu Xinyao Yu Yang Wang Yingwen Liu Xiaogang Qiang Junjie Wu Ping Xu 《Frontiers of Physics》2020,15(6):61501
One of the most important multipartite entangled states, Greenberger–Horne–Zeilinger state (GHZ), serves as a fundamental resource for quantum foundation test, quantum communication and quantum computation. To increase the number of entangled particles, significant experimental efforts should been invested due to the complexity of optical setup and the difficulty in maintaining the coherence condition for high-fidelity GHZ state. Here, we propose an ultra-integrated scalable on-chip GHZ state generation scheme based on frequency combs. By designing several microrings pumped by different lasers, multiple partially overlapped quantum frequency combs are generated to supply as the basis for on-chip polarization-encoded GHZ state with each qubit occupying a certain spectral mode. Both even and odd numbers of GHZ states can be engineered with constant small number of integrated components and easily scaled up on the same chip by only adjusting one of the pump wavelengths. In addition, we give the on-chip design of projection measurement for characterizing GHZ states and show the reconfigurability of the state. Our proposal is rather simple and feasible within the existing fabrication technologies and we believe it will boost the development of multiphoton technologies. 相似文献
34.
The analysis of vitamin D status, with special emphasis on 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, is gaining interest in clinical studies due to the classical and non-classical effects attributed to this prohormone. In this research, the influence of the two steps preceding determination (viz. sample collection and preparation) on the quantitative analysis of vitamin D and its more important metabolites has been studied. Two preparation approaches, deproteination and solid-phase extraction (SPE), have been evaluated in terms of sensitivity to delimit their application, thus establishing that detection of 1,25-dihydroxyvitamin D cannot be addressed by protein precipitation. Concerning sample collection, serum and plasma reported high accuracy (above 83.3%) for vitamin D and metabolites, while precision, expressed as relative standard deviation, was below 12.9% for all analytes in both samples. Statistical analysis revealed that serum and plasma provided similar physiological levels for vitamin D3, 24,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D3, while significantly different levels were obtained for 1,25-dihydroxyvitamin D3, always higher in plasma than in serum. Sample collection and treatment have proved to be significant in the analysis of vitamin D and its relevant metabolites. 相似文献
35.
Andrey A. Dobrynin 《Discrete Mathematics》2019,342(1):74-77
Distance between two vertices is the number of edges in a shortest path connecting them in a connected graph . The transmission of a vertex is the sum of distances from to all the other vertices of . If transmissions of all vertices are mutually distinct, then is a transmission irregular graph. It is known that almost no graphs are transmission irregular. Infinite families of transmission irregular trees of odd order were presented in Alizadeh and Klav?ar (2018). The following problem was posed in Alizadeh and Klav?ar (2018): do there exist infinite families of transmission irregular trees of even order? In this article, such a family is constructed. 相似文献
36.
Naomichi Hatano 《Molecular physics》2019,117(15-16):2121-2127
The Lindblad equation for a two-level system under an electric field is analyzed by mapping to a linear equation with a non-Hermitian matrix. Exceptional points of the matrix are found to be extensive; the second-order ones are located on lines in a two-dimensional parameter space, while the third-order one is at a point. 相似文献
37.
Yanmin Yu 《Molecular physics》2019,117(9-12):1360-1366
ABSTRACTPotential energy surfaces and molecular dynamics of the intramolecular 1, 3-dipolar cycloaddition and ene reaction of a nitrile oxide with an alkene were performed in the gas phase and in dichloromethane with density functional theory. One hundred trajectories were propagated in the gas phase and in dichloromethane, respectively. Twenty percent of the trajectories in the gas phase involve bicyclic intermediate and the mean time gap is 472fs. A dynamically stepwise reaction is observed. In dichloromethane, more reactive trajectories were obtained and the time gap is larger than that in the gas phase. 相似文献
38.
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40.
The ground-state phases of two-dimensional spin-2 Bose–Einstein condensate with Rashba spin–orbit coupling are studied. For the equal strengths of the density-density interaction and the spin-exchange interaction, we classify the ground-state phases into four types of stable phases with spin–orbit coupling and spin singlet-pairing interaction in momentum space, i.e., the ring phase, the stripe phase, the triangular phase and the square phase. With increasing the spin–orbit coupling strength, the system undergoes a sequence phase transitions from the ring phase to the stripe phase, and to the square phase for the attractive spin singlet-pairing interaction (), and the system undergoes a sequence phase transitions from the ring phase to the stripe phase, to the triangular phase, and to the square phase for the repulsive spin singlet-pairing interaction (). 相似文献