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991.
A physical scheme for the implementation of quantum superdense coding has been proposed in Cavity QED. The detuned interaction
between Λ-type three-level atoms and coherent fields constitute the main superdense coding process. The quantum superdense
coding can be realized in an easier way, and the atoms are not excited during the whole process, so the effect of atomic decay
is eliminated naturally. 相似文献
992.
993.
人力资源成本预算与控制的理论分析 总被引:6,自引:0,他引:6
本的分析是人力资源成本管理体系研究的一部分,着重于探讨在人力资源成本管理体系中,人力资源成本的预算与控制与该体系中其他几部分之间的关系,研究人力资源成本管理实践中成本预算与控制的理论基础,并提出一些新的思路。 相似文献
994.
Ming Qian Zhonghua Shen Jian Lu Xiaowu Ni Qiang Li Yimin Xuan 《Optics and Lasers in Engineering》2008,46(6):461-468
Our recent work revealed that speckles can be formed when nanofluids containing a proper volume fraction of nanoparticles are illuminated by a monochromatic laser beam [Qian M, Liu J, Yan M-S, Shen Z-H, Lu J, Ni XW, et al. Investigation on utilizing laser speckle velocimetry to measure the velocities of nanoparticles in nanofluids. Opt Express 2006; 14: 7559–66]. In this paper, two different physical models are established to figure out the speckle-formation mechanism. The photon–nanoparticle-collision model emphasizes the random collisions between photons and nanoparticles, and Monte Carlo method is used to simulate how the incident photons move in the vessel containing nanofluids. However, in the electric-dipole model, each illuminated nanoparticle becomes an electric dipole and sends out scattering lights, and the coherent addition of the scattering lights from nanoparticles is numerically calculated. Finally, from the numerical results, the speckle-formation mechanism is figured out. 相似文献
995.
In this paper, local a priori, local a posteriori and global a posteriori error estimates are obtained for TQC9 element for the biharmonic equation. An adaptive algorithm is given based on the a posteriori error estimates. 相似文献
996.
SUPER TOUGH GELS WITH A DOUBLE NETWORK STRUCTURE 总被引:1,自引:0,他引:1
Tasuku Nakajima Takayuki Kurokawa Hidemitsu Furukawa Yoshimi Tanaka Yoshihito Osada 龚剑萍 《高分子科学》2009,27(1)
Living tissues work with fantastic functions in soft and wet gel-like state.Thus,hydrogels have attracted much attention as excellent soft and wet materials,suitable tot making artificial organs for medical treatments.However, conventional hydrogels are mechanically too weak for practical uses.We have created double network (DN) hydrogels with extremely high mechanical strength in order to overcome this problem.DN gels are interpenetrating network (IPN) hydrogels consisting of rigid polyelectrolyte and s... 相似文献
997.
Chih‐Cheng Lee Kun‐Ming Yeh Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2008,46(24):7960-7971
Two vinyl homopolymers poly(N‐(4‐(4‐(4‐vinylbenzyloxy)styryl)phenyl)‐N‐phenylbenzenamine) (PVST ) and poly(4‐vinyltriphenylamine) (PTPA ) containing pendant hole‐transporting triphenylamine and 4‐oxystyryltriphenylamine groups, respectively, were synthesized by radical polymerization and employed as hosts for tris(2‐phenylpyridine) iridium [Ir(ppy)3] phosphor. Structural influences of the hole‐transporting groups upon optoelectronic properties were investigated by photophysical, electrochemical, and electroluminescent methods. The polymers were readily soluble in common organic solvents and their weight‐average molecular weights (Mw) were 5.68 × 104 and 1.90 × 104, respectively. The emission spectra (both photoluminescence, PL and electroluminescent, EL) of the blends [PTPA with 4 wt % Ir(ppy)3] showed dominant green emission (517 nm) attributed to Ir(ppy)3 due to efficient energy transfer from PTPA to Ir(ppy)3. The HOMO levels of PVST and PTPA, estimated from onset oxidation potentials in their cyclic voltammograms, were ?5.14 and ?5.36 eV, which are much higher than ?5.8 eV of the conventional poly(9‐vinylcarbazole) (PVK) host owing to high hole‐affinity of the triphenylamine groups. The optoelectronic performances of phosphorescent EL devices, using PVST and PTPA as hosts and Ir(ppy)3 as dopant (indium tin oxide, ITO/poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS)/PVST or PTPA:Ir(ppy)3(4 wt %):PBD(40 wt %)/BCP/Ca/Al), were investigated. The maximum luminance and luminance efficiency of the PTPA device were 9220 cd/m2 and 6.1 cd/A, respectively, which were significantly improved relative to those of PVK and PVST. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7960–7971, 2008 相似文献
998.
In this paper,the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ~1H NMR and ESI-MS.The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state,respectively,and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference.In concentration of>40 mmol/L,the duplex can gelate DMSO, and... 相似文献
999.
M.Randic首先引入了Wiener.Hosoya指标,该指标可用于对分子的结构,性质和活跃性等方面进行研究.有且仅有一个顶点的度大于或等于3的树称为spider.本文对直径为d,且具有最大Wiener-Hosoya指标的spider进行了刻划. 相似文献
1000.
向量优化问题有效解的稳定性 总被引:1,自引:0,他引:1
运用标量化的方法,通过锥正定真有效解的上半连续性讨论了无限维赋范空间中锥有效解的部分上半连续性,证明了锥有效解的通有稳定性.在此基础上,进一步证明,在Baire纲的意义下,绝大多数的向量优化问题至少存在一个锥正定真有效解是本质的有效解,换句话说,绝大多数的向量优化问题锥有效解是几乎下半连续的. 相似文献