PuC^n＋（n=1,2,3）分子离子的势能函数与稳定性

用密度泛函B3LYP方法对PuC^n (n=1,2,3)分子离子进行理论研究,结果表明：PuC^ 、PuC^2 分子离子能稳定存在,基态电子状态是X^8∑^-(PuC^ )和X^9∑^-(PuC^2 ),并导出了相应的几何性质、力学性质和光谱数据。PuC^3 (^6∑、^8∑）分子离子不能稳定存在。     

PuCn+(n=1,2,3)分子离子的势能函数与稳定性

用密度泛函B3LYP方法对PuCn+(n=1,2,3)分子离子进行了理论研究,结果表明:PuC+、PuC2+分子离子能稳定存在,基态电子状态是X8Σ-(PuC+)和X9Σ-(PuC2+),并导出了相应的几何性质、力学性质和光谱数据.PuC3+(6Σ、8Σ)分子离子不能稳定存在.     

563—660nm波段S02^＋的PHOFEX连续谱

在超声分子束条件下，利用380．85nm的电离激光使SO2分子经由[3+1]共振增强多光子电离(REM—PI)产生纯净的S02^+(X^2A1)分子离子，用另一束解离激光在可见光波长区(563—660nm)扫描获得了光解碎片S0^+的激发(PHOFEX)谱．从563—66nm波长区SO^+的无结构连续谱以及S02^+解离的效率随波长增加而减少的实验事实，提供了S02^+(E，D，C)电子态附近存在α^2A2对称性排斥态的证据，分析了产生S0^+的[1+1]光解机理：(1)S02^+(X^2A1)首先经由单光子激发到达B^2B2中间态的密集能级区；(2)吸收另一个光子到达S02^+(E，D，C)电子态附近的α^2A2排斥态，经由α^2A2排斥态产生了到S0^+(X^2∏)+O(^3P6)的直接解离．     

CS2+( 2Πg )的(1+1)光解离动力学研究

在气束条件下,利用483．2nm的激光（3＋1）共振增强多光子电离（REMPI）CS2分子以产生CS2＋离子源,用另一束可调谐激光在424－482nm内,通过对CS2^+(x^2∏g)(1+1)双光子共振解离产生的碎片离子发谱的探测,来获取CS2^+的光解离动力学信息,光解离碎片S^+的激光发谱（PHOFEX）可归属为CS2^+（A^2∏u,3/2(v′=0-4,v′＝v1_(1/2)v2-)←X^2′∏g,3/2(0,0,0))和（A^2∏u,1/2(v=0-4)←X^2∏g,1/2(0,0,0))跃迁,对CS2^+光解离动力学的研究表明,其产生S^+的通道为：（i)CS2吸收一个光子从基态X^2∏g共振激发至A^-2∏u态,（ii)已布居的A^-2∏u态的振动能级和X^2-∏g态的高振动能级产生耦合,（iii)吸收第二个光子从上述耦合的振动能级进一步激发至B^2∑u^+态,再通过B^-2∑u^+态与^4∑^-态间的自旋－轨道相互作用,经由4∑^-排斥态解离产生S^+_CS。     

钠分子三重激发态的光谱分析

利用逆向微扰法、WKB节点法和夫兰克-康登因子相位法等计算方法,分析了Na2分子的2^3∑g^+(v=15,J27)→a^3∑u^+、2^3∏g(v=11,J=11)→a^3∑u^+和4^3∏g(v=12,J=23）→a^3∑u^+的微扰增强光学-光学双共振实验光谱,计算了2^3∑g^+、a^3∑u^+、2^3∏g、4^3∏g的电子态势能曲线以及相关跃迁的电子跃迁电偶矩,并在此基础上将理论计算的光谱与实验光谱相比较。     

CS2^1B2（^1∑u^＋）态预离解产物CS的振转布居研究

用一束波长为210．27nm的激光将CS2分子激发至预离解态^1B2(^1∑u^+)，用另一束激光通过激光诱导荧光(UF)方法检测碎片CS，在250．5～286．5nm获得了CS碎片A^1П←X^1∑^+振转分辨的激发谱，通过对光谱强度的分析，获得了CS碎片v″=0～8的振动布居和v″=1，4～8振动态的转动布居，结果发现，碎片CS的振动布居呈双模结构，分别对应于CS2分子^1B2(^1∑u^+)态的两个解离通道，即CS(X^1∑^+，v″=0～9)+S(^3PJ)和CS(X^1∑^+，v″=0～1)+S(^1B2)，由此得到两个解离通道的分支比S(^3P1)：S(^1B2)为5．6±1．2。与前人193nm处的研究结果相比，210．27nm激发更有利于S(^3P1)通道的生成。此外，实验还发现CS的转动布居不满足热平衡分布，为两个Boltzmann分布的合成。     

S2（B^3∑u^-→X^3∑g^-（v＇≥18,0））弥散谱带的自旋-轨道从头计算

采用从头计算方法从理论上解释了实验中双原子分子S2（B^3∑u^-→X^3∑g^-吸收谱中谱带（18,0）开始出现的弥散现象.计算了包含自旋-轨道耦合（SOC）的B^3∑u^-和排斥的1^5∏u,2^3∑u^＋态的电子势能曲线.对于（18,0）谱带开始弥散,给出了与其他文献不同的物理解释.计算结果表明B^3∑u^-与1^5∏u,2^3∑u^＋态的SOC作用导致预解离对谱带的弥散起着决定作用,并与实验结果作了比较,符合很好.     

SAC／SAC—CI方法研究LiH基态（X^1∑^＋）以及A^1∑^＋、B^1П激发态结构与性质

利用SAC（Symmetry-Adapted Cluster）／SAC-CI（Configuration Interaction）理论中的SAC-CI-NV（Non-variational）and SAC-CI-V（Variational）方法，以及6-311＋＋g^＊＊基组对LiH分子的基态（X^1∑^＋）和A^1∑^＋、B^1П激发态的平衡结构以及性质进行了研究计算．两种方法对LiH分子的三个态进行处理。并将优化结果与现有实验值进行了比较，结果显示，理论计算值都与实验值符合较好．同时利用SAC/SAC-CI方法中的AllProperties关键字对我们所关心的LiH分子的基态（X^1∑^＋）和A^1∑^＋、B^1П激发态进行了计算，并给出各个态在其平衡点位置处的偶极矩、振子强度和抗磁化率等一些性质参数，对以后的实验作理论参考．     

大气氧谱带的实验研究

利用流动余辉装置,首次报道了金属镍表面催化基态氧原子O（^3P）复合从而获得大气氧谱带O2（b1∑g^+→X^3∑g^-）的（0,0）电子跃迁光谱。并且对反应管壁去激活O2（b1∑g^+）的动力学过程进行了分析,间接证实了O2（b1∑g^+)的浓度在反应管中非稳态的变化过程。最后对O2(b1∑g^+)的形成机理进行了简单的讨论。     

UHn+(n=1,2,3)分子离子的势能函数和稳定性

用密度泛函B3LYP方法研究了UH+, UH2+和UH3+分子离子的势能函数. UH+具有稳定极小点, UH2+是具有极大和极小的"能量阱"分子离子, UH3+不能稳定存在. 同时由势能函数导出了UH+和UH2+的力学性质和光谱数据.     

Self-organization of five species in a cyclic competition game

Cyclic competition game models, particularly the “rock–paper–scissors” model, play important roles in exploring the problem of multi-species coexistence in spatially ecological systems. We propose an extended “rock–paper–scissors” game to model cyclic interactions among five species, and find that two of the five can coexistent when biodiversity disappears, which is different from the “rock–paper–scissors” game. As the number of fingers is five, we named the new model the “fingers” game, where the thumb, forefinger, middle finger, ring finger, and little finger cyclically dominate their subsequent species and are dominated by their former species. We investigate the “fingers” model in two ways: direct simulations and nonlinear partial differential equations. An important finding is that the number of species in a cyclic competition game has an influence on the emergence of biodiversity. To be specific, the “rock–paper–scissors” model is in favor of maintaining biodiversity in comparison with the “fingers” model when the variables (population size, reproduction rate, selection rate, and migration rate) are the same. It is also shown that the mobility and reproduction rate can promote or jeopardize biodiversity.     

Experimental study on downstep in Chinese intonation

Downstep in pitch contour of Chinese Putonghua is examined using subtly designed sentences by controlling tone combinations. The results show both automatic and nonautomatic downstep phenomena exist in Chinese. In non-automatic downstep, low tones compress downwards the pitch range of the following syllables. and the main influence of downstep is on topline. Low tone not only lower the topline behind it, but also raise the high tones before it, the effects are compatible with each other. In automatic downstep, the topline of pitch contour in intonational phrase is presented as a linear downtrend, but it differs among speakers due to the effect of personal stress practice. In comparison with downstep phenomenon in other tone or non-tone languages, the downstep ratio in Chinese is not constant, and the domain of downstep is not limited within the adjacent tones.     

Contrastive analysis on tone between Putonghua and Taiwan Mandarin

The differences of the pitch and duration of Chinese syllables between Putonghua （PTH） and Taiwan Mandarin （TM） were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that： For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3〉T2〉T1〉T4 in PTH, while it is T1〉T2〉T3〉T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.     

Abelian-Higgs phase of SU(2) QCD and glueball energy

It is shown that SU(2) QCD admits an dual Abelian-Higgs phase, with a Higgs vacuum of a type-Ⅱ superconductor. This is done by using a connection decomposition for the gluon field and the random-direction approximation. Using a bag picture with soft wall, we presented a calculational procedure for the glueball energy based on the recent proof for wall-vortices [Nucl. Phys. B 741(2006)1].     

High efficiency filtering using two-dimensional photonic crystal coupled cavity structures

Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.     

Signal generation in an isotropic medium in scanning electron acoustic microscope

Based on the research in Ref. [5][Materials Science and Engineering, 1989; A122： 57 63], an improved model of heat source is set up, the different modes of Lamb wave in an isotropic sample generated by a chopped electron beam at frequency f are obtained with integral transform and normal function expansion method, and the output signal of PZT coupled at the back surface of the sample is found out. The generation mechanism of SEAM （Scanning Electron Acoustic Microscopy） signal is discussed. It shows that the SEAM is a near field imaging technique with high spatial resolution and its best lateral spatial resolution is about 2√2α （α is the radius of the focused electron beam）. Some of experimental results of SEAM images are presented in the paper and it shows that the spatial resolution of SEAM is better than 0.5 μm and smaller than the thermal diffusion length of the sample. Therefore the character of near field imaging in SEAM is also proved experimentally.     

Real-time restoration of rotational blurred image using gradient-loading

The key to the restoration of rotational motion blurred image is how to restore the image under a low cost and to correct the irreversibility of the degradation function matrix.Based on the special qualities of degradation function matrix and precise deduction in space-domain, we present a new approach using gradient-loading for restoration of rotational blurred image.By easily adding a gradient operator, the irreversibility of the original matrix is corrected and can be applied for inverse filtering then.Gradientloading is the optimized approach which combines the advantages of both the approaches using constrained least square filtering and traditional diagonal-loading.Compared with the approach using least square filtering, its peak signal-to-noise ratio (PSNR) is improved from 3.18 to 6.46dB, while the computing time is reduced to 1/2-1/3.Experimental results demonstrate the effectiveness, noise-resistibility, robustness, and low complexity of this approach, which make it more suitable for real-time environment.     

All-Optical Logic Device Using Bent Nonlinear Tapered Y-Junction Waveguide Structure

We propose an all-optical logic device made of a bent tapered Y-junction waveguide with a Kerr-type nonlinear interface. It could provide an AND gate, OR gate, and exclusive-OR (XOR) gate. We could obtain different transmission results by adjusting the bending angle. The numerical simulation results show that the device functions as AND, OR, and XOR gates.     

Real-time, continuous-wave terahertz imaging by a pyroelectric camera

Real-time, continuous-wave terahertz (THz) imaging is demonstrated. A 1.89-THz optically-pumped farinfrared laser is used as the illumination source, and a 124 × 124 element room-temperature pyroelectric camera is adopted as the detector. With this setup, THz images through various wrapping materials are shown. The results show that this imaging system has the potential applications in real-time mail and security inspection.