Dynamics of vibrational chaos and entanglement in triatomic molecules： Lie algebraic model

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.     

不同氮源制备CNx纳米管薄膜及其低场致电子发射性能

采用高温热解法,分别以氯化铵(NH4Cl)和乙二胺(C2H8N2)为氮源在洁净的硅片上沉积生长CNx纳米管薄膜.利用扫描电子显微镜、高分辨率透射电子显微镜和拉曼光谱对CNx纳米管进行形貌观察和表征.结果显示不同氮源制备出的CNx纳米管薄膜的洁净度、有序度以及纳米管的结构明显不同.热解乙二胺(C2H8N2)/二茂铁(C10H10Fe)制备出的结晶度较低的"竹节状"结构CNx纳米管平行基底表面有序生长,而且低场致电子发射性能优越,开启电场1.0V/μm,外加电场达到2.89V/μm时发射电流密度为860μA/cm2.     

Structure and room-temperature ferromagnetism of Co-doped ZnO DMS films

Co-doped ZnO diluted magnetic semiconductor films were prepared on Si(100) substrates by magnetron sputtering system and the Co content varies from 0.01 to 0.15. The X-ray diffraction results showed ZnO of the wurtzite structure. The ferromagnetism was observed at room temperature. The X-ray near-edge absorption spectroscopy revealed that Co substitutes for Zn²⁺ ions in the valence of +2 state in the Co-doped ZnO films.     

高辐射效率超宽谱脉冲辐射天线的设计与实验

设计了一种采用共面TEM馈电结构的抛物反射面超宽谱脉冲辐射天线,分析了该种馈电结构的阻抗特性与辐射特性。实验表明当馈入电压为3kV、前沿180ps的超宽谱脉冲时,该天线主轴辐射场测试距离与峰值场强之积平均值达到18.3kV,相较于常用的TEM喇叭馈电的超宽带反射面天线,其辐射效率有了显著的提高。     

Evolution analysis of the states of the EZ model

Based on suitable choice of states, this paper studies the stability of the equilibrium state of the EZ model by regarding the evolution of the EZ model as a Markov chain and by showing that the Markov chain is ergodic. The Markov analysis is applied to the EZ model with small number of agents, the exact equilibrium state for N = 5 and numerical results for N=18 are obtained.     

椭圆偏振技术研究VHF-PECVD高速沉积微晶硅薄膜的异常标度行为

采用VHF-PECVD技术高速沉积了不同生长阶段的微晶硅薄膜,通过椭圆偏振技术研究了生长过程中微晶硅薄膜表面粗糙度的演化.实验结果表明,沉积气压P_g=300 Pa时,β=0.81,其超出标度理论中β最大值为0.5范围,出现异常标度行为.这表明微晶硅薄膜高速生长中还存在其他粗糙化增加的因素,此粗糙化增加的因素与阴影作用有关. 关键词： 微晶硅薄膜 椭偏光谱法 生长机制 表面粗糙度     

Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40?C400?nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.     

Analysis on electrical characteristics of high-voltage GaN-based light-emitting diodes

<正>In order to investigate their electrical characteristics,high-voltage light-emitting-diodes(HV-LEDs) each containing four cells in series are fabricated.The electrical parameters including varying voltage and parasitic effect are studied. It is shown that the ideality factors(IFs) of the HV-LEDs with different numbers of cells are 1.6,3.4,4.7,and 6.4.IF increases linearly with the number of cells increasing.Moreover,the performance of the HV-LED with failure cells is examined.The analysis indicates that the failure cell has a parallel resistance which induces the leakage of the failure cell.The series resistance of the failure cell is 76.8Ω,while that of the normal cell is 21.3Ω.The scanning electron microscope(SEM) image indicates that different metal layers do not contact well.It is hard to deposit the metal layers in the deep isolation trenches.The fabrication process of HV-LEDs needs to be optimized.     

Solution-combustion synthesis of Tb-doped Y3Al5O12 nanoparticles

Nano-sized YAG:Tb powder phosphors were prepared by a solution-combustion method, using the general inorganic salts as starting materials. The X-ray diffraction (XRD) measurements showed that the precursor can be well-crystallized at 900 °C. As-prepared particles have sizes mostly in the range between 30 and 100 nm as obtained by scanning electron microscope (SEM) and transition electron microscope (TEM). Selected area electron diffraction (SAED) patterns proved that the larger particles are monocrystalline. The effects of annealing temperature and Tb-doping concentration on the luminescence intensity were studied.     

Efficient continuous-wave eye-safe region signal output from intra-cavity singly resonant optical parametric oscillator

We report an efficient continuous-wave (CW) tunable intra-cavity singly resonant optical parametric oscillator based on the multi-period periodically poled lithium niobate and using a laser diode (LD) end-pumped CW 1064 nm Nd:YVO₄ laser as the pump source. A highly efficiency CW operation is realized through a careful cavity design for mode matching and thermal stability. The signal tuning range is 1401-1500 nm obtained by varying the domain period. The maximum output power of 2.2 W at 1500 nm is obtained with a 17.1 W 808 nm LD power and the corresponding conversion efficiency is 12.9%.