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101.
The survival probability of super heavy nuclei produced in cold fusion reactions is studied by using the standard Fermi gas level density formula and analyzed with fission and neutron evaporation characteristics predicted in different theoretical models. The level density formula used in this letter suppresses the ratio of neutron emission width to fission width, Гn/Гf. The dependence of Гn/Гf on the saddle point level density parameter and excitation energy is also investigated. 相似文献
102.
Scheme for teleporting an unknown atomic state to any node in a quantum communication network 下载免费PDF全文
We propose a scheme for teleporting an unknown atomic state. In order to realize the teleportation to any node in a quantum communication network, an n-atom Greenberger-Horne-Zeilinger (GHZ) state is needed, which is utilized as the quantum channel. From this n-atom GHZ state, two-node entanglement of processing and receiving teleported states can be obtained through the quantum logic gate manipulation. Finally, for the unequally weighted GHZ state, probabilistic teleportation is shown. 相似文献
103.
CHEN Chang-Yong 《理论物理通讯》2008,49(4):871-876
We propose a potentially practical scheme to implement an approximate three-qubit Toffoli gate by a single resonant interaction in dissipative cavity QED in which the cavity mode decay and atomic spontaneous emission are considered. The scheme does not require two-qubit controlled-NOT gates but uses a three-qubit phase gate and two Hadamard gates, where the approximate phase gate can be implemented by only a single dissipative resonant interaction of atoms with the cavity mode. Discussions are made for the advantages and the experimental feasibility of our scheme. 相似文献
104.
高压LED因其自身突出的特点在照明领域有着潜在的应用优势,但作为一种新型功率LED,其光电热特性仍需深入研究。该实验对6和9V GaN基高压LED芯片进行了相同结构和工艺条件的封装,对封装样品进行了10~70℃的变温度光谱测试,并进行了从控温平台温度到器件结温的转换。为保证器件的电流密度相同,6和9V样品光谱测试的工作电流分别设定为150和100mA。结果显示,结温升高会导致蓝光峰值波长红移、波长半高宽增大、光效下降和显色指数上升等现象。在相同平台温度和注入功率下,9V样品的结温低于6V样品;随着温度的升高,9V样品波长半高宽的增加量比6V样品少1.3nm,光效下降量少1.13lm·W~(-1),显色指数上升量少0.28。以上表明,与低压LED相比,高压LED有着更低的工作结温和更小的温度影响。原因在于,相同环境温度下高压LED具有更好的电流扩展性和更少的发热量。此特性在高压LED的研究、发展与应用等方面具有参考价值。此外,峰值波长仍与结温有着较好的线性度,在光谱设备精度较高的情况下可继续作为结温的敏感参数。 相似文献
105.
The soft mode dynamics and related properties of perovskite, ABO3-type crystals have been studied using the operator form of the model Hamiltonian proposed by Pytte. The correlations have
been evaluated using the double time thermal Green’s function technique and Dyson’s equation. Without any decoupling, the
higher order correlations, appearing in the dynamical equation, have been evaluated using the renormalized Hamiltonian. The
dielectric properties are directly related to the optical soft mode. The phonon width and shift have been calculated for different
structural phases. The analysis of the temperature dependence of microwave loss tangent and dielectric constant explains the
experimental results. 相似文献
106.
I. V. Dobrynina 《Mathematical Notes》2000,68(3):306-311
In this paper, the problem of finite width for free products of groups with amalgamated subgroup is considered.
Translated fromMatematicheskie Zametki, Vol. 68, No. 3, pp. 353–359, September, 2000. 相似文献
107.
M. Caymax M. Houssa G. Pourtois F. Bellenger K. Martens A. Delabie S. Van Elshocht 《Applied Surface Science》2008,254(19):6094-6099
Important progress has been made in the passivation of Ge/gate dielectric interfaces. One important approach is by thermally oxidized GeO2 interface and ALD high-k layers, with an interface state density Dit ∼ 2 × 1011 cm−2 eV−1. Another approach is with an epi-Si/SiO2 interface, resulting in similar Dit. Hysteresis and Vth shift, however, are still not optimal. Extensive material characterization and theoretical insights help us understanding the root cause of these remaining issues and show the way to improved interface control. 相似文献
108.
分子梭在分子开关、分子逻辑门、信息存储等领域有着潜在的应用价值,是超分子化学领域的研究热点之一。本文综述了光驱动分子梭的研究进展:重点举例介绍了荧光光谱识别法和圆二色光谱识别法这两种识别光驱动分子梭位置状态的方法;阐述了构建光驱动轮烷分子梭的新型方法学,包括光驱动环糊精[2]轮烷和[1]轮烷分子梭的定向合成,举例介绍了光间接驱动的轮烷分子梭,以及光驱动[3]轮烷型分子梭和分子梭聚合物;举例说明了光驱动分子梭的功能性应用,用光驱动分子梭来模拟分子水平的逻辑门,研究光驱动分子梭体系中的能量传递机理,以及非溶液态的光驱动分子梭;并对分子梭今后的发展做了展望。 相似文献
109.
Intrinsic Flexibility of the Zeolitic Imidazolate Framework ZIF‐7 Unveiled by CO2 Adsorption and Hg Intrusion 下载免费PDF全文
Dr. Marc Pera‐Titus 《Chemphyschem》2014,15(8):1581-1586
ZIF‐7, built as an assembly of ZnII centers and benzimidazolate ligands, shows prominent S‐shaped isotherms upon CO2 adsorption that can be attributed to sorbate‐induced gate‐opening phenomena involving a narrow‐to‐large pore phase transition. This peculiar sorption pattern can be captured via the formulation of thermodynamic isotherms, providing a direct enthalpic and entropic view of the gate‐opening process. Relying on such an approach, an energy barrier with preferential enthalpic nature for CO2 adsorption/desorption in the gate‐opening region could be unveiled. Moreover, the elastic energy involved during the gate‐opening process was revisited to 1.4–2.8 kJ mol?1 of solid in the temperature range 273–323 K, matching the value measured by isostatic compression of a ZIF‐7_lp sample filled with DMF and showing a dominant entropic contribution. 相似文献
110.