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961.
Haixuan Huang Jing Yang Xiangdong Gong Lili Wan Kai Wang Yeyong Zheng Xuan Han 《Optics Communications》2009,282(21):4198-4202
Based on the Left Perfect Shuffle (LPS) optical communication network constructed by cascade multi-stage LPS interconnection, using Looping algorithm, any arbitrary sequence of the input signals can be realized. However, instead of obtaining the simultaneous state codes of the same level node switches through mathematical analytical expressions directly, only routing tags of each channel can be obtained through mathematical analytical expressions so as to draw out topological chart of the network to obtain the state codes implied in the chart. Thus, the states of the switches cannot be directly programmed and controlled by computer in practical application. In this paper, based on the Looping algorithm, a method of stage code matrixes is presented to resolve this problem. By using the method, the simultaneous state codes of the same level’s four node switches can be directly obtained, which is convenient for the computer to provide controlled signals needed to finish the permutation for each node switch. The method of stage code matrixes provides further theoretical basis for the realization of optical switching by integration of Perfect Shuffle and high-speed optical switches. 相似文献
962.
The entanglement dynamics of two vibrational modes of a polyatomic molecule coupled by Coriolis interaction to overall molecular rotation is studied in terms of two negativities, N(t) and Ns(t), respectively, defined by the minimum of the eigenvalues and by the sum of the negative eigenvalues of the partial transpose of a density matrix. Various initial states are the products of Dicke states and the products of coherent states of vibrations and rotations. Formaldehyde is taken as an example, and the von Neumann entropy s(t) is simulated for the comparison with both negativities. It is shown that negativity Ns(t) is positively correlated with entropy s(t), and the correlated behavior between negativity N(t) and entropy s(t) strongly depends on initial states. However, these three indicators of entanglement display a dominantly positive correlation for the coherent states with small or large parameters. In addition, for the latter state two quantities N(t) and s(t) are nearly unchanged for a long time. This time can be further increased by the increasing of vibrational quantum number so that molecular information processing and quantum computing is allowed. These results are useful in quantum information theory. 相似文献
963.
Eun Kwang Lee Wan Seop Kim Kyu Won Lee Heungbin Lim Jong In Lee Hyun Gyu Lee Nam Hwi Hur 《Solid State Communications》2009,149(1-2):37-40
Nanoporous magnets are new promising materials particularly useful in biological assays and ion separations. This letter deals with a simple method for making porous magnets composed of cobalt ferrite, where polymer colloidal spheres were used as sacrificial templates. Compared with the bulk congener the porous cobalt ferrite shows enhancements in coercive field and magnetization, which could be associated with the presence of nanopores ordered three dimensionally. Using the sponge magnet complete removal of magnetic Cu and Fe ions was achieved while partial removal was observed with porous silicate having the same size of nanopores. 相似文献
964.
965.
Quantum systems that are confined to circuit geometries are called quantum circuits. Macroscopic superconducting circuits
are quantum circuits which can be modelled using a Quantisation by Parts scheme based on the macroscopic wave function approach of Feynman. This paper studies the circuit composed of an input wire
and an output plate. We find that in order to achieve a consistent theory of supercurrent flow we have to generalize the quantisation
by parts scheme to quantise in a path space. The generalized theory predicts a current flow down the wire into the plane.
In addition to a current flowing radially outwards in the plane, the theory allows a circulating current round the origin.
Strikingly, the circulating current can flow clockwise or anti-clockwise in such a way as to generate a magnetic moment of
magnitude half of a Bohr magneton for an orbiting electron in an atom and a magnetic flux half that of the magnetic flux quantum
of a superconducting ring. There is also the possibility of a macroscopic superposition of the two states of opposing circulating
currents resembling a Schr?dinger’s cat situation. Furthermore, we outline a setup involving an external magnetic field that
may allow experimental tests of the theory. 相似文献
966.
The solid neon matrix isolated spectrum of CO2 are recorded in the 2–5 μm region. Natural and 13C or 18O enriched CO2 samples were used and the nν1 + ν3 (n = 0, 1, 2) series bands of different CO2 isotopologues have been observed. The solid neon matrix shift due to Fermi-resonance of bands within the same vibrational polyad is analyzed. 相似文献
967.
968.
Fu-Ming Wang Chien-Chieh Hu Shen-Chuan Lo Yung-Yun Wang Chi-Chao Wan 《Solid State Ionics》2009,180(4-5):405-411
The effect of EO side chain functionalization on the transport and electrochemical properties of polysiloxane electrolytes has been examined in this report. First, a study of the electrochemical stability of the electrolytes by linear sweep voltammetry shows that the polymer electrolytes have a negligible effect on the electrolyte stability windows. In addition, the parameters of cation mobility in polysiloxane electrolytes, such as ionic transference numbers and diffusion coefficients, were increased by increasing the lengths of the EO side chain. However, cation mobility in polymer structures is quite different compared to liquid-based systems and is probably suppressed, resulting in their polymer structure. Therefore, Positron Annihilation Lifetime Spectroscopy (PALS) was used to study the relationship between orthopositronium (o-Ps) lifetime, free volume radius, free volume of micro voids and EO side chain affection at different temperatures. Finally, a battery application with LiCoO2 and LiFePO4/polymer electrolyte/lithium metal electrode was monitored for its potential use in the future. 相似文献
969.
SUN Ya-Guang RONG Shu-Ting WU Yong-Li YU Wan WANG Chuan-Sheng ZHANO Wan-Zhong GAO En-Jun 《结构化学》2009,28(9)
The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n(H3CAM=4-hydroxypyridine-2,6-dicarboxylic acid,bipy=4,4′-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid,4,4′-bipyridine and manganese carbonate under hydrothermal conditions,and its crystal structure was determined by X-ray diffraction method.The crystal belongs to the monoclinic system,space group P21/n with a=10.110(2),b=20.159(4),c=17.861(4) ,β=99.67(3)°,V=3.5884(12) nm3,Mr=901.47,Z=4,Dc=1.669 g·cm-3,μ=0.798 mm-1,F(000)=1840,the final R=0.0713 and wR=0.1853.The complex forms a 1-D chain bridged by HCAM,protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H…O hydrogen bonds,and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework. 相似文献
970.
Pyridotriazol-1-yloxypyrimidine 3 reacts with arylboronic acids under palladium-free, Cs2CO3, (0.8%) H2O2, and DME conditions to produce heteroaryl ethers 4-16 in good yields comparable to the oxidative palladium-catalyzed reaction. The yields of aryl ethers 17-19 from quinazoline 2 with (0.8%) H2O2 were modest. Hydrogen peroxide is superior to dioxygen as an oxidant in these reactions. 相似文献