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1.
Planar laser-induced fluorescence is currently widely applied to research on combustion. However, conventional approaches for semi-quantitative measurement could not provide the satisfactory solution and the problem due to collisional quenching remains to be solved. This paper describes the two-dimensional (2D) quenching-time-constant measurement of OH:A 2 +( = 1) and NO:A 2 ( = 0) in flame cross sections at atmospheric pressure. These measurements involve 1–2 ns decay time of the excited state using a high-speed image intensifier and a tunable laser with a pulse duration of 3 ns at FWHM. The correlation factors of the exponential fits for the fluorescence decays after the laser pulse were larger than 0.999 in all experiments presented in this study. Furthermore, the measured Stern-Volmer plots of the quenching rate at 1.0, 1/2, 1/3, and 1/4 atm pressure using the same experimental apparatus was confirmed to have a linear relationship for both OH and NO, showing that the 2D decay-time measurements of 1–2 ns have been successful. For NO:A 2 ( = 0), the obtained quenching rates inside the inner cone and in the outer flame in the NO-seeded methane-air Bunsen flame were 8.7 × 108 and 7.8 × 108 s–1, respectively, and for OH:A 2 ( = 1), the obtained quenching rate mapping in the outer flame was around 5.6 × 108 s–1 in the methane-air flame.  相似文献   

2.
根据塞曼效应理论和激光磁共振光谱技术(LMR)的基本原理,讨论了双原子分子2П态的塞曼效应特性并导出了解释分子塞曼跃迁的简明代数拟合方程,用这些方程对14N16O(X2Π1/2,3/2)及15N16O(X2Π3/2) (υ=1←0)的LMR谱线进行数据拟合,得到塞曼跃迁上、下子能级的gJ因子值和二级塞曼效应因子k2.将按Hund耦合情形(a)及过渡情形(ab)的理论和拟合方程计算出的磁场位置分别与实验结果相比较,结果表明对NO分子而言,过渡情形(ab)能较真实反映它的耦合情况,且在较高强度磁场下,必须计及二级塞曼修正.验证了采用上述代数拟合方程实现新分子LMR谱线标识和指认的可靠性,并提供了系统的处理方法.  相似文献   

3.
采用杂化密度泛函(DFT)之B3LYP/6-311G**方法研究了NxHy-Fe(x=0~2,y=0~3)配位簇的几何结构和振动光谱,讨论了在纯铁催化剂上,氮分子和氢分子逐步合成氨的反应机理,结果表明,合成氨过程可能经历N2和N2H2物种,在优化结构的基础上,计算了各个模型的振动频率并解释了有关实验结果。  相似文献   

4.
We carry out both four-dimensional (4D×2D) and six-dimensional (6D) quantum dynamics on a parametrically time- and temperature-dependent effective Hamiltonian for H2/D2(v = 0,j = 0)–Ni(100) collision process. Such an effective potential was derived within a theoretical framework of mean-field approximation by considering weakly correlated interaction between molecular degrees of freedom, phonon modes and electron– hole pair (elhp) coupling through a Hartree-product-type wave function, where the initial state distribution of the surface modes and elhp coupling were introduced through Bose– Einstein and Fermi– Dirac probability factor, respectively. The temperature-dependent dissociation and state-to-state transition probabilities for H2/D2(v = 0,j = 0)–Ni(100) system are depicted as a function of initial kinetic energ of the incoming diatom. Though such effect appears negligibly small for H2(v = 0,j = 0)–Ni(100) system, it is prominent in the case of D2(v = 0,j = 0)–Ni(100) collision. It appears that the change of dissociation and transition probabilities of D2 with the increase of surface temperature is exclusively dictated by the phonon modes directed along Z-axis, but the effect of elhp coupling particularly for transition probabilities is insignificant.  相似文献   

5.
Rate constants have been calculated using quasi-classical trajectories (QCT) for the vibrational relaxation of highly excited O2:O2(X3Σ?,vi) + O2(X3Σ?,0) → O2(X3Σ?,vf) + O2(X3Σ?) with 22 ≤vi≤28. The present full-dimensional QCT results agree very well with recent quantum reduced dimensionality calculations, giving further support to the hypothesis that the observed experimental jump in depletion rates would be due partially to enhanced vibrational relaxation.  相似文献   

6.
以双层系统的ZHK 模型为基础,研究了双层量子霍尔系统在朗道填充因子取υ = 1=2 这种状态的静态涡流解。ZHK模型是一种包含Chern-Simons 规范相互作用的有效理论。为了简便,假定涡流具有柱对称的结构,随后写出了无量纲的非线性运动方程组,并分析了解的渐进行为。另外,在自对偶条件下,确定了自耦合常数的形式,并写出了关于密度的自对偶方程。最后,使用数值方法找到了类型分别为(0,1),(0, -1),(1,-1) 和(-1,-1) 的涡流解。发现拓扑数为(1,-1) 的涡流是不稳定的,它会衰变为(1,0) 和(0,-1) 两种涡流。数值结果表明,拓扑数为(0,-1)和(-1,-1)的涡流确实是自对偶涡流解。We investigate the static vortex solutions of a bilayer quantum Hall state at the Landau-level filling factor υ = 1=2. This work is based on the ZHK model, which is an effective field theory including Chern-Simons gauge interactions. We deduce the dimensionless nonlinear equations of motion for vortices possessing cylindrically symmetry, and analyze the asymptotical behaviors of solutions. Additionally, we analyze the values of critical coupling constants under the self-dual condition, and obtain the self-dual equations. Finally, vortices of type (0,1),(0, -1),(1,-1) and (-1,-1) are solved with numerical methods. We reach the conclusion that vortex of type (11,-1) is unstable, which will decay to (1,0) and (0,-1). The vortices of type (0,-1) and (-1,-1) are self-dual solutions from numerical results.  相似文献   

7.
基于ab initio势能面(KBNN PES)[1],用耦合通道超球坐标理论研究了碰撞能等于0.5 eV时H D2(v=0,j=0)的积分,微分截面.对于反应性碰撞,计算的积分截面表明由于深势阱的存在使得这一绝热反应产物的分布表现出一种近似的统计行为.计算的微分截面反映该体系存在着长寿命的中间络合物;对于非反应性碰撞(传能过程),平动—平动传能过程更有效,且其积分截面随着转动量子数的增大而显著减少.通过反应性碰撞和非反应性碰撞积分截面的比较,发现在低能碰撞情况,非反应性碰撞更容易进行.  相似文献   

8.
Total rotational energy transfer rates have been measured at 1330 K for specific rotational levels in the OHA 2 +, = 0 state in collisions with H2O. Rotational levels ranging fromN = 0 to 15 were studied. Measurements were performed in the post-flame region of a stoichiometric H2/O2/He flame operating at 25 mbar. Quenching rates following excitation of individual upper rotational states were also measured. The RET and quenching rates both exhibit monotonic decreases with increasing rotational quantum number.  相似文献   

9.
<正>Ω~-I(J~P)=0(3/2~+)Status:****The unambiguous discovery in both production and decay was by BARNES 64.The quantum numbers follow from the assignment of the particle to the baryon decuplet.DEUTSCHMANN 78 and BAUBILLIER 78 rule out J=1/2 and find consistency with J=3/2.AUBERT.BE 06 finds from the decay angular distributions ofΞ_c~0→Ω~-K~+andΩ_(c~0)→Ω~-K~+that J=3/2;this depends on the spins of theΞ_c~0 andΩ_c~0 being J=1/2,their supposed values.We have omitted some results that have been superseded by later experiments.See our earlier editions.  相似文献   

10.
11.
12.
Intensities for the γ(A2Σ+?→?X2Π), ε(D2Σ+?→?X2Π) and (D2Σ+?→?A2Σ+) bands for NO have been calculated using the Molecular Quantum Defect Orbital (MQDO) methodology. Radiative lifetimes for the A2Σ+ and D2Σ+ vibrational Rydberg states have also been determined. The present results are in excellent accord with measurements available in the literature. Additionally, predictions for a number of unknown intensities and radiative lifetimes are made, given their potential usefulness.  相似文献   

13.
《Nuclear Physics B》2001,604(3):537-550
Using explicit results for the four-point correlation functions of the Wess–Zumino–Novikov–Witten (WZNW) model we discuss the conformal embedding osp(4|4)1 = osp(2|2)−2 ⊕ su(2)0. This embedding has emerged in Bernard and LeClair's recent paper cond-mat/003075. Given that the osp(4|4)1 WZNW model is a free theory with power law correlation functions, whereas the su(2)0 and osp(2|2)−2 models are CFTs with logarithmic correlation functions, one immediately wonders whether or not it is possible to combine these logarithms and obtain simple power laws. Indeed, this very concern has been raised in a revised version of cond-mat/003075. In this paper we demonstrate how one may recover the free field behaviour from a braiding of the solutions of the su(2)0 and osp(2|2)−2 Knizhnik–Zamolodchikov equations. We do this by implementing a procedure analogous to the conformal bootstrap programme Nucl. Phys. B 241 (1984) 333. Our ability to recover such simple behaviour relies on a remarkable identity in the theory of elliptic integrals known as Legendre's relation.  相似文献   

14.
借助光子导出了E=mc2和m=m01-v2/c2.  相似文献   

15.
本文采用法拉弟效应的激光磁共振光谱技术,研究了-氧化氮分子14N16OX2Π3/2R(1.5)v=0→1和同位素分子15N16OX2Π3/2Q(1.5)v=0→1跃迁的FLMR光谱,实验给出了样品浓度和信号强度之间的关系及调制磁场强度与FLMR信号强度之间的关系。  相似文献   

16.
Coherent vacuum ultraviolet (VUV) radiation was generated by four-wave difference frequency mixing (VUV=212) of pulsed dye laser radiation in carbon monoxide (CO). The frequency 1 was tuned to the C 1+(=0)X 1+(=0) two-photon transition, while the dye laser frequency 2 was scaned around 17650 cm–1 which corresponds to the A 1(=7)«C 1+(=0) transition energy. The VUV intensity was found to be strongly wavelength dependent. The analysis of the spectrum revealed (i) that the VUV intensity was enhanced by the rotational levels of the A 1(=7) state and (ii) that the off-resonance excitation in the C 1+(=0)X 1+(=0) two-photon transition greatly contributed to the present four-wave mixing process. The effects of pumping laser detuning, saturation and foreign gases are briefly discussed.  相似文献   

17.
18.
用原子分子反应静力学原理推导出CrHn(n =0,+1,+2)的电子状态及其离解极限.对H原子采用6-311++G**基组,对Cr原子采用SVP(split valence polarization)全电子基组,用B3PW91方法计算了它们的平衡几何、电子状态,在此基础上分别计算CrH, CrH+的Murrell-Sorbie解析势能函数和CrH2+的解析势能函数及其对应的力常数、光谱参数,理论计算值与实验值和文献计算值符合较好.从离解极限和通道解释了不同的势能函数形状.计算表明:CrH+的势能曲线均具有对应于稳定平衡结构的极小点,说明CrH+可稳定存在.而CrH2+离子的势能曲线对应于不稳定的排斥态,说明CrH2+是不稳定的.  相似文献   

19.
利用1A′态的势能面[ Ho et al., J. Chem. Phys. 116, 4124 (2002)],采用准经典轨线方法研究了在不同碰撞能条件下,S(1D) +H2(v=0, j=0)→SH+H反应的立体动力学性质. 通过计算得到了描述反应物速度矢量k与产物的转动角动量矢量j′这两个矢量相关的分布函数P(r)、描述反应物速度矢量k、产物速度矢量k′与产物的转动角动量矢量j′这三个矢量相关的二面角分布函数P(r)以及描述反应产物角动量极化的分布函数P(r,r).计算结果表明产物的转动角动量矢量j′在空间具有明显的定向和取向效应,并且产物的转动角动量具有强烈的极化. 另外,计算结果还表明这些立体动力学性质对碰撞能非常敏感.  相似文献   

20.
采用高灵敏度,高分辨率激光磁共振光谱(LMR)方法在6μm谱段测量了自由基分子NH_2v_2带的σ谱(△M_1=±1)。重复了前人已测过的谱,结果与之较好符合。并观测到了新谱,在14支激光谱线下共获得约115支塞曼(Zeeman)跃迁谱线,其中在6支激光谱线下新测得的谱线91支。  相似文献   

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