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1.
在分子束条件下测量了He(2^3S)+N2O(X)→N2O^+(A^2Σ^+)+He(^1So)+e^-反应的Penning电离光学光谱,求得了N2O^+(A^2Σ^+)态的初生态相对振动布居。以He(2^3S)+N2(X)→N^+2(B^2Σ^+u)+He(^1So)+e^-为参考反应,测量了He(2^3S)+BN2O^+(A^2Σ^+)+He(^1So)+e^-反应的速率常数KN2O^+(A)  相似文献   

2.
CO(a)与CS2和CS传能反应中激发态碎片形成速率   总被引:1,自引:0,他引:1  
本文利用流动余辉技术研究了亚稳态CO(a)与CS2和CS的传能反应,测定了反应产生的激发态碎片CS(A)和CS(a)的形成速率常数。CO(a)与CS2传能反应中CS(A)和CS(a)的形成速率常数分别为3.46×10^-11cm^3·molec^-1·sec^-1和1.14×10^-10cm^3·molec^-1·sec^-1。CO(a)与CS传能反应中CS(A)和CS(a)的形成速率常数分别为1  相似文献   

3.
采用脉冲辐解动态吸收光谱法研究了Br^-2和Cl^-2自由在诱导氧化N-二异丙基磷酰化甲硫氨酸(NDM)水溶液的过程,结果表明:Br^-2和Cl^-2进攻NDM中的硫原子形成含硫三电子键NDM(S∴X)(X=Br,Cl)它们分别在400nm和390nm处有最大吸收峰,形成和衰变均呈一级反应,测定了不同条件下氧化反应的速率常数,推导了反应机理,并从分子结构观点与甲硫氨酸水溶液的Br^-2.Cl^-2  相似文献   

4.
本文在束-气条件下研究了亚稳态原子He(2^3S)与CH2Cl2间的传能反应,测得了由该反应产生的CH(A^2△-X^2П),CH(B^2∑^-X^2П)CH(C^2∑^+-X^2П)和H原子(Balmer系)的化学发光光谱。通过对CH(A,B)的光谱进行计算机模拟,推测出初手的CH(A^2△,v^1=0-2)态振动分布为No:N1:N2=100:40±5:19±2,CH(A^2△,v^1=0-0  相似文献   

5.
本文利用流动余辉技术研究了亚稳态原子He(2^3s)和Ne(^3p0.2)与POCl3分子的传能反应,获得了激发态碎片PO(A)和PO(B)的发射光谱,测定了He(2^3s)与POCl3反应中PO(A)和PO(B)的形成速率常数,其数值分别为:KPO(A)=3.68×10^-11cm^3·molecule^-1S^-1和KPO(B)=9.40×10^-11cm^3·molecule^-1·S^-1  相似文献   

6.
硫化Mo—K—Rh/Al2O3表面物种的XPS研究   总被引:2,自引:0,他引:2  
假定单一物种的XPS峰形为高斯形,对钼,硫和铑峰进行理论拟合,计算各状态物种表面原子浓度,它们的存在形式各为MoS2,富硫环境的MoS2+x,未完全硫化还原的Mo^6+和Mo^5+,S^6+,单质S^0或Sn,S^2-和富硫环境中的硫钼结构成(S-S)^2-硫链和Rh^n+(n=3,2,1,0)。分析发现,催化剂加铑使钼易被硫化还原,铑钼作用可以稳定Rh^n+的存在。  相似文献   

7.
测得了315 ̄330nm超声射流冷却下SO2^1A2-^1A1激光诱导荧光(LIF)激发谱,获得了7个有明显K结构的C型跃迁的转动子带分辨谱,并将70个转动子带归属为(1,m,1)-(0,0,0)和(0,n,1)-(0,0,0)(4≤m≤7,8≤n≤10)的跃迁带系。光谱分析得到SO2^1A2-^1A1跃迁的带源v00、^1A2态弯曲振动频率v′2,非谐性常数X22′分别为(27950±5)、(2  相似文献   

8.
贺庆林  包明 《波谱学杂志》1996,13(3):297-302
测定了15种三(2-甲基-2-苯基丙基)锡苯氧乙酸酯化合物的^13CNMR谱,利用模型化合物对比及化学位移计算比较等方法,对全部谱线进行了归属,讨论了化合物^13CNMR谱与结构的关系,求得对苯环碳的取代基化学位移参数(SCS):Cipso=30.0,Cortbo=-13.8,Cmeta=0.8,Cpara=-7.5。  相似文献   

9.
含R2dtc配体和V=O基的金属簇红外光谱研究   总被引:1,自引:1,他引:0  
本文报道两类含R2dtc配体的金属簇的红外光谱特点及某些规律,含R2dtc的立方簇合物在400-500cm^-1有较宽而弱的吸收,可归结于M-μ3S振动。M-Sdtc在330-380cm^-1,C-N振动在1470-1510cm^-1。二甲基dtc配体立方的v(C-N)与v(C=S)比值他二烷基dtc立方烷的相应振动分别蓝移和红移,可归结于甲基超共轭效应所致。「V2Cu2S4(R2dtc)2(PhS)2」^2-和「VCu4S4(R2dtc)n(PhS)4-n」^3-(n=0,1,2)的M-μ3S振动分别出现在480和465cm^-1,可作为区别两类化合物的一个指标。另一类含(R2dtc)2V2O2(μ-S)2单元的金属簇中,V-O伸缩频率在844-970cm^-1范围内,(Et4N)「V2S2O3(Et2dtc  相似文献   

10.
以NH4Cl作助溶剂,碳还原硫酸钙的方法合成了CaS:Ce。在紫外光激发下,CaS:Ce中存在着Ce^3+的^2D-^2F5/2(500nm)和^2D-^2F7/2(550nm)跃迁发射,但在蓝色光激发下,只有波峰为532nm半宽度为92nm的宽带发射。当Ce^3+的浓度为0.075mol%时,^2D-^2F5/2跃迁发射强度与^2D-^2F7/2跃迁发射强度相等,而532nm发射猝灭。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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].  相似文献   

15.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

16.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

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19.
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.  相似文献   

20.
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.  相似文献   

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