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1.
Molecular structure, vibrational frequency and infrared intensity of UF6 are investigated by using the revised Perdew Burke-Enzerhof function with the triple-zeta polarized basis set. The calculation results are in good agreement with the experimental values and indicate the existence of a stable U2F6 molecule with a multiple bonded U2 unit. The calculation results also predict that the D3d symmetry of U2F6 is more stable than D3h. The optimized geometries, vibrational frequencies, and infrared intensities are also reported for U2F6 molecules in D3d symmetry. In addition, the isotopic shift of vibrational frequencies of the two molecules under isotopic substitution of uranium atom are also investigated with the same method. The U2F6 molecule is predicted to be better than UF6 for laser uranic isotope separation. 相似文献
2.
3.
We studied the electron heat transport across a non‐local stochastic magnetic field and a non‐local non‐stochastic magnetic field in tokamak plasmas. Analytical results and numerical simulation results were compared with conditions of a stochastic and a non‐stochastic magnetic field respectively in this article. Parameter of stochasticity in perturbed magnetic field was found not tobe a key factor in influencing effective radial heat conductivity in radial direction of tokomak when Chirikov parameter is close to one (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
4.
The effects of ultraviolet-C radiation (UV-C, 11.8?W/m2), single-cycle and multiple-cycle high hydrostatic pressure (HHP at 200, 400 or 600?MPa) on microbial load and physicochemical quality of raw milk were evaluated. Reductions of aerobic plate count (APC) and coliform count (CC) by HHP were more than 99.9% and 98.7%, respectively. Inactivation efficiency of microorganisms increased with pressure level. At the same pressure level, two-cycle treatments caused lower APC, but did not show CC differences compared with single-cycle treatments. Reductions of APC and CC by UV-C were somewhere between 200?MPa and 400/600?MPa. Both HHP and UV-C significantly decreased lightness and increased pH, but did not change soluble solids content and thiobarbituric acid-reactive substances’ values. Two 2.5?min cycles of HHP at 600?MPa caused minimum APC and CC, and maximum conductivity. Compared with HHP, UV-C markedly increased protein oxidation and reduced darkening. 相似文献
5.
在综述电化学近50年来比能量提高情况的基础上,讨论了现代科技发展对电池比能量的要求,以及当今电池能在多大程度上满足这些要求,并讨论了进一步提高电池比能量的可能性及可能途径. 相似文献
6.
By using a model Hamiltonian with competing antiferromagnetic (AFM) spin density wave (SDW) and d-wave
superconductivity orders, the effect of next-nearest-neighbour (nnn)
hopping on spin and charge structures in high-temperature
superconductors is investigated at finite temperatures. For an
optimally doped sample, we find that the AFM order magnitude in the
vortex core is firstly enhanced and then suppressed, accompanied
with a ``positively → negatively → positively" charged vortex structure transition with increasing nnn
hopping strength, which implies that the AFM order is unnecessarily
bounded to an electron-rich vortex core. In addition, a charge
ordering pattern with four negatively charged peaks localized in a
small region is also found around the vortex core centre without net
charge. Recent scanning-tunneling-microscopy experimental
observations of the checkerboard structure are hopefully
understood. 相似文献
7.
Xingran Cui Leirong Tian Zhengwen Li Zikai Ren Keyang Zha Xinruo Wei Chung-Kang Peng 《Entropy (Basel, Switzerland)》2020,22(11)
Heart rate variability (HRV) has been widely used as indices for autonomic regulation, including linear analyses, entropy and multi-scale entropy based nonlinear analyses, and however, it is strongly influenced by the conditions under which the signal is being recorded. To investigate the variability of healthy HRV under different settings, we recorded electrocardiograph (ECG) signals from 56 healthy young college students (20 h for each participant) at campus using wearable single-lead ECG device. Accurate R peak to R peak (RR) intervals were extracted by combing the advantages of five commonly used R-peak detection algorithms to eliminate data quality influence. Thorough and detailed linear and nonlinear HRV analyses were performed. Variability of HRV metrics were evaluated from five categories: (1) different states of daily activities; (2) different recording time period in the same day during free-running daily activities; (3) body postures of sitting and lying; (4) lying on the left, right and back; and (5) gender influence. For most of the analyzed HRV metrics, significant differences (p < 0.05) were found among different recording conditions within the five categories except lying on different positions. Results suggested that the standardization of ECG data collection and HRV analysis should be implemented in HRV related studies, especially for entropy and multi-scale entropy based analyses. Furthermore, this preliminary study provides reference values of HRV indices under various recording conditions of healthy young subjects that could be useful information for different applications (e.g., health monitoring and management). 相似文献
8.
本文提出了一个新的未知量子态共享方案,使用一个非最大纠缠的五粒子Cluster态作为量子通道来实现任意两粒子未知量子态的共享. 即就是发送方(Alice),接收方(Bob)和控制方(Charlie)共享一个非最大纠缠的五粒子Cluster态. 与以前传统方案不同,在本方案中发送方引入一个辅助粒子,并对其手中的粒子进行正交完备基测量,而接收方不需要引入辅助粒子,只需要执行适当的幺正操作,即可以方便的完成信息的顺利接收. 控制方通过对自己手中的粒子做单粒子投影测量来控制和协助通信双方,使得任意两粒子的未知量子态共享方案得以成功实现.
关键词:
量子态共享
五粒子Cluster态
正交完备基测量
单粒子投影测量 相似文献
9.
Li-an Bian Peiguo Liu Qihui Zhou Chenxi Liu Hanqing Liu Song Zha 《Optical and Quantum Electronics》2018,50(5):220
Total absorption is realized theoretically in a graphene-outside-cavity resonator. The structure is composed of the FP-Fano hybrid resonance cavity. Changing the thickness of grating exciting Fano resonance, the absorption-mode number can be tuned effectively. For the focused double-mode absorption, the resonances behave insensitively with the variation of chemical potential of graphene. Varying the geometry of grating can control the coupling extent of two modes. Also, by manipulating the period number of two-side multilayers around graphene, the absorption, shift and number of modes are governed. 相似文献
10.