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排序方式: 共有220条查询结果,搜索用时 515 毫秒
211.
Jun-Tong Liu Qing-Wen Wang Lei Li 《International Journal of Theoretical Physics》2017,56(8):2423-2432
In this paper, we first define a generalized (f,g)-skew information \(\left |I_{ \rho }^{(f, g)}\right |(A)\) and two related quantity \(\left |J_{ \rho }^{(f, g)}\right |(A)\) and \(\left |U_{ \rho }^{(f, g)}\right |(A)\) for any non-Hermitian Hilbert-Schmidt operator A and a density operator ρ on a Hilbert space H and discuss some properties of them. And then, we obtain the following uncertainty relation in terms of \(\left |U_{ \rho }^{(f, g)}\right |(A)\): which is a generalization of a known uncertainty relation in Ko and Yoo (J. Math. Anal. Appl. 383, 208–214, 11).
相似文献
$$\begin{array}{@{}rcl@{}} \left|U_{ \rho}^{(f, g)}\right|(A)\left|U_{ \rho}^{(f, g)}\right|(B)\geq \beta_{(f, g)}\left|Tr\left( f(\rho)g(\rho)[A, B]^{0}\right)\right|^{2}, \end{array} $$
212.
受某些实际网络节点数按几何级数增长现象的启发,构造了每个时间步中按当前网络规模成比例地同时加入多个节点的节点数加速增长的网络模型.研究表明,在增长率不是很大的情况下网络度分布仍然是幂律的,但在不同的增长率r下幂律指数是不同的.得到了幂律指数介于2到3之间可调的无标度网络模型,并解析地给出了幂律指数随增长率变化的函数关系.数值模拟还显示,网络的平均最短距离随r减小而簇系数随r增大.
关键词:
复杂网络
无标度网络
生长网络模型
节点数加速增长网络模型 相似文献
213.
Hai-Liang Zhu Yong-Jun Pan Xian-Jiang Wang Kai-Bei Yu 《Journal of chemical crystallography》2004,34(3):199-202
The title complex, [Co(phen)(H2O)4](SO4)2(H2O) (phen = 1,10-phenanthroline) was prepared in aqua tert-butylperoxohydrogen solution. X-ray single crystal structure determination reveals that the complex consists of a phenanthrolinatocobalt(II)tetrahydrate dication, two uncoordinated water molecules and a sulfate anion. It crystallizes in the orthorhombic space group Pbca with a = 8.856(1), b = 18.318(3), c =21.918(5) Å, V = 3555.6(11) Å3. The coordination geometry at each cobalt(II) atom is a slightly distorted octahedron. 相似文献
215.
Let F be a family of meromorphic functions in D,and let Ψ(≠0) be a meromorphic function in D all of whose poles are simple.Suppose that,for each f ∈F,f≠0 in D.If for each pair of functions {f,g}(?) F,f' and g' share Ψ in D,then F is normal in D. 相似文献
216.
D. M. Wang Y. N. Wu Y. S. Huang S. Wu 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,84(3):451-457
We study the aggregation mechanisms of metal nanoclusters on the Si(111)7 × 7
reconstructed surface using a correlated nucleation model, in which the nucleation and
growth behavior of a cluster (irreversible or partially reversible growth) depend on the
local environment of the cluster. The kinetic Monte Carlo simulation of the model shows
that with increasing temperature, the correlated nucleation effect causes a transition of
growth behavior from asymmetric adatom aggregation between faulted and unfaulted half
cells with a strong preference of occupation of faulted half cells, to compact cluster
aggregation with a low occupation preference at high temperatures. As a result the
preference as a function of the temperature exhibits a nonmonotonous behavior, with a
maximum located at the temperature at which the transition of growth behavior has been
observed. Both the simulated cluster morphologies and the quantitative analysis of the
cluster distribution are in good agreement with the results observed from relevant growth
experiments. 相似文献
217.
用W态实现量子隐形传态的腔QED方案 总被引:1,自引:1,他引:0
本文提出一个用类W态作为纠缠通道,采用不同于文献[19]的测量基来实现量子隐形传态的腔QED方案.在这个方案里,只需要利用原子和腔场通过J-C哈密顿量发生共振相互作用,一步就可制备纠缠通道.另外,通过原子与腔场的失谐作用,利用Bell态测量,可实现概率为100%的量子隐形传态.在目前的腔QED技术条件下,该方案是可以实现的. 相似文献
218.
219.
The discrepancy between the trend in the diffusion coefficient of a lithium ion (DLi+) and that in the activation energy of ion hopping signals hidden factors determining ion transport kinetics in layered olivine phosphate materials (LiMPO4). Combining density functional theory (DFT) calculations and the Landau–Zener electron transfer theory, we unravel this hidden factor to be the electronic coupling between redox centers of the host materials. The ion transport process in LiMPO4 is newly described as an ion-coupled electron transfer (ET) reaction, where the electronic coupling effect on DLi+ is considered by incorporating the electronic transmission coefficient into the rate constant of the transfer reaction. The new model and DFT calculation results rationalize experimental values of DLi+ for various LiMPO4 (M = Fe, Mn, Co, Ni) materials, which cannot be understood solely by the calculated activation barrier of ion hopping. Interestingly, the electronic coupling between host redox centers is found to play an essential role. Particularly, the sluggish ion mobility in LiFePO4 is due to a very weak electronic coupling. The obtained insights imply that one can improve the rate performance of intercalation materials for metal-ion batteries through modifying the electronic coupling between redox centers of host materials.The discrepancy between the trend in the diffusion coefficient of lithium ions (DLi+) and that in the activation energy of ion hopping signals hidden factors determining ion transport kinetics in layered olivine phosphate materials (LiMPO4). 相似文献
220.
《中国化学快报》2023,34(8):107919
Opportunities coexist with challenges for the development of carbon-based cathodes with a high energy density applied for zinc ion hybrid capacitors (ZIHCs). In the present study, a facile and effective surface engineering approach is demonstrated to greatly improve the energy storage ability of commercial carbon paper (CP) in ZIHC. Benefiting from the introduced oxygen functional groups, larger surface area and improved surface wettability upon air calcination, the assembled aqueous ZIHC with the functionalized carbon paper (FCP) exhibits a much higher areal capacity of 0.22 mAh/cm2 at 1 mA/cm2, outperforming the counterpart with blank CP by over 5000 times. More importantly, a superior energy density and power density of 130.8 µWh/cm2 and 7460.5 µW/cm2, are respectively delivered. Furthermore, more than 90% of the initial capacity is retained over 10000 cycles. This surface engineering strategy to improve the energy storage capability is potentially applicable to developing a wide range of high-energy carbon electrode materials. 相似文献