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131.
Dynamics of vibrational chaos and entanglement in triatomic molecules: Lie algebraic model 下载免费PDF全文
In this paper, the dynamics of chaos and the entanglement in triatomic molecular vibrations are investigated. On the classical aspect, we study the chaotic trajectories in the phase space. We employ the linear entropy to examine the dynamical entanglement of the two bonds on the quantum aspect. The correspondence between the classical chaos and the quantum dynamical entanglement is also investigated. As an example, we apply our algebraic model to molecule H2O. 相似文献
132.
Parasitic bipolar amplification in a single event transient and its temperature dependence 下载免费PDF全文
Using three-dimensional technology computer-aided design (TCAD) simulation, parasitic bipolar amplification in a single event transient (SET) current of a single transistor and its temperature dependence are studied. We quantify the contributions of different current components in a SET current pulse, and it is found that the proportion of parasitic bipolar amplification in total collected charge is about 30% in both 130-nm and 90-nm technologies. The temperature dependence of parasitic bipolar amplification and the mechanism of the SET pulse are also investigated and quantified. The results show that the proportion of charge induced by parasitic bipolar increases with rising temperature, which illustrates that the parasitic bipolar amplification plays an important role in the charge collection of a single transistor. 相似文献
133.
Quantum Monte Carlo study on the phase transition for a generalized two-dimensional staggered dimerized Heisenberg model 下载免费PDF全文
In order to gain a deeper understanding of the quantum criticality in the explicitly staggered dimerized Heisenberg models,we study a generalized staggered dimer model named the J0-J1-J2 model,which corresponds to the staggered J-J ' model on a square lattice and a honeycomb lattice when J1/J0 equals 1 and 0,respectively.Using the quantum Monte Carlo method,we investigate all the quantum critical points of these models with J1/J0 changing from 0 to 1 as a function of coupling ratio α=J2/J0.We extract all the critical values of the coupling ratio αc for these models,and we also obtain the critical exponents ν,β/ν,and η using different finite-size scaling anstz,.All these exponents are not consistent with the three-dimensional Heisenberg universality class,indicating some unconventional quantum ciritcial points in these models. 相似文献
134.
We apply strong magnetic fields of H=28.5 to 43 T to suppress superconductivity (SC) in the cuprates Bi2Sr2-xLaxCuO6+delta (x=0.65, 0.40, 0.25, 0.15, and 0), and investigate the low temperature (T) normal state by 63Cu nuclear spin-lattice relaxation rate (1/T1) measurements. We find that the pseudogap (PG) phase persists deep inside the overdoped region but terminates at x approximately 0.05, which corresponds to the hole doping concentration of approximately 0.21. Beyond this critical point, the normal state is a Fermi liquid that persists as the ground state when superconductivity is removed by the magnetic field. A comparison of the superconducting state with the H-induced normal state in the x=0.40 (Tc=32 K) sample indicates that there remains substantial part of the Fermi surface even in the fully developed PG state, which suggests that the PG and SC are coexisting matters. 相似文献
135.
The (2+1)-dimensional breaking soliton equation describes the interaction of a Riemann wave propagating along the y-axis with a long wave along the
x-axis. In this paper, with the aid of symbolic computation, six
kinds of new special exact soltion-like solutions of
(2+1)-dimensional breaking soliton equation are obtained by using
some general transformations and the further generalized
projective Riccati equation method. 相似文献
136.
为了提高医疗技术水平,加快医务人员对医疗信息数据的分析,使医疗信息数据运行更加顺畅,减少数据存储所占空间,需要对医疗信息数据存储系统进行设计。当前的医疗信息数据存储系统对医疗信息数据进行存储时,利用FPGA构建系统硬件,以硬件为基础将医疗信息数据存储,但在存储过程中,没有将冗余数据清除,导致存储空间易满,容量变小,存在正常医疗信息数据无处安放的问题。为此,提出一种基于模糊处理的医疗信息数据存储系统设计方法。该方法首先对医疗信息数据的来源进行统计,根据数据来源实现医疗数据的硬件构造,然后利用医疗信息数据中特征相似数据间的中介点实现数据聚类,完成对医疗信息数据的聚类存储,最后采用高斯混合模型对冗余医疗数据进行特征分析,以分析结果为基础,利用分数阶Fourier变换对冗余医疗信息数据进行删除操作,由此完成了基于模糊处理的医疗信息数据存储。实验结果证明,所提方法增加数据存储空间容量,减少对冗余数据的存储,加快医疗信息数据的存储速度,提高数据存储精度,为该领域研究发展提供强有力的依据。 相似文献
137.
在针-针电极结构的放电装置中以环境空气作为工作气体,大气压下产生了刷形等离子体羽。尽管使用的是直流电源,但放电发光呈现出脉冲性质,发光脉冲频率几乎不受气体流速的影响,但与电源输出功率成正相关关系。等离子体羽的长度与气体流速或者电源功率成正相关关系。通道出口附近,777.4 nm的氧原子谱线强度分布是非对称的,阴极附近处的谱线强度高于阳极附近处的谱线强度。远离通道出口位置,谱线强度逐渐趋于轴对称分布。电学特性和10 μs曝光高速影像结果表明,空气等离子体羽实际上是由拱形放电丝在远离通道出口的运动过程中叠加而成,同时放电从弧光放电丝向均匀辉光放电转化。 相似文献
138.
利用化学气相沉积法(CVD),气-液-固(VLS)生长法则在表面溅有金属Au催化剂层的1 cm×1 cm的Si片上制备三元Zn2GeO4纳米线。X射线衍射仪(XRD)测试结果表明,锌源与锗源质量比为8:1时可成功制备出Zn2GeO4纳米结构;扫描电子显微镜(SEM)测试结果表明,Zn2GeO4纳米线直径为100 nm,长度为10~11 μm;光致发光(PL)测试结果表明,Zn2GeO4纳米线在432和480 nm处具有两个发光峰,最后对其生长机理进行了分析。 相似文献
139.
Yanmin Huang Danping Shi Laijun Liu Guizhong Li Shaoying Zheng Liang Fang 《Applied Physics A: Materials Science & Processing》2014,114(3):891-896
Bi0.5Na0.5TiO3 (BNT)-doped BaFe0.5Nb0.5O3 (BFN) ceramics were synthesized by a two-step solid-state reaction. Temperature dependence of dielectric properties measured at different frequencies was investigated over broad temperature and frequency ranges. Impedance spectroscopy and universal dielectric response were employed to study the relaxation behavior and conductivity mechanism of the ceramics in a frequency range from 40 Hz to 100 MHz and a temperature range from 300 K to 800 K. The complex plane impedance data revealed the bulk and grain boundary contributions toward conductivity processes in the form of semicircular arcs. The high-temperature conductivity of ceramics is attributable to thermally activated second ionized oxygen vacancy. 相似文献
140.
采用poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b’]dithiophene-2,6-diyl][3-?uoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]](PTB7)作为有机发光二极管器件的阳极修饰层,制备了结构为indium tin oxide(ITO)/PTB7(不同浓度)/N,N’-Bis(naphthalen-1-yl)-N,N’-bis(phenyl)benzidine(NPB,40 nm)/8-hydroxyquinoline(Alq3,60 nm)/LiF(1 nm)/Al的系列器件,同时研究了不同浓度的PTB7对器件性能的影响.PTB7的最佳浓度为0.25 mg/mL,器件性能得到明显的改善,起亮电压为4.3 V.当驱动电压为14.6 V时,最大亮度为45800 cd/m2,最大电流效率为9.1 cd/A.与没有PTB7修饰的器件相比,其起亮电压降低了1.9 V,最高亮度提升了78.5%.器件性能提高归因于PTB7的插入使得空穴注入和传输能力大大改善. 相似文献