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81.
Elastic scattering of two H(^2Sg) and N(^4Su) atoms at low temperatures and accurate spectroscopic parameters of NH (X^3∑^-) radical 下载免费PDF全文
This paper reports that the interaction potential for the X3Z- state of NH radical is constructed at the CCSD(T)/ cc-PV6Z level of theory. Using this potential, this paper calculates the spectroscopic parameters (De, Re, ωe, ωeχe, αe and Be) and their values are of 3.578eV, 0.10368nm, 3286.833cm^-1, 78.433cm^-1, 0.6469cm^-1 and 16.6735cm^-1 respectively, which are in excellent agreement with the experiments. Then the total of 14 vibrational states has been found when J=0 by solving the radial Schrodinger equation of nuclear motion. For each vibrational state, the vibrational manifolds are reported for the first time. And last, the total cross sections, s-wave, p-wave and d-wave cross sections are computed for the elastic collisions between two ground-state atoms (hydrogen and nitrogen) at low temperatures. It finds that the total elastic cross sections are dominated by s-wave scattering when the collision energy is below 10^-6a.u. The pronounced shape resonance is found at energy of 6.1 × 10^-6a.u. Calculations have shown that the shape resonance comes from the p-wave contributions. 相似文献
82.
苏丹红系列染料在有机溶液中的紫外-可见光谱研究 总被引:1,自引:0,他引:1
研究了苏丹红Ⅰ、苏丹红Ⅲ和苏丹红Ⅳ在非极性溶剂石油醚和极性溶剂乙腈及乙腈-水混合溶液中的紫外-可见光谱特征。在极性溶剂中苏丹红系列的可见区特征吸收峰比在非极性溶液中略有红移;在乙腈-水混合溶液中,苏丹红Ⅰ的特征吸收峰比在乙腈溶剂中红移,最大红移达13 nm,吸收强度最大增幅为34.5%;苏丹红Ⅲ的特征吸收峰红移8 nm,吸收强度增幅为11%;苏丹红Ⅳ的特征吸收峰先红移后蓝移,吸收强度增幅数仅为2.5%。造成这一变化的原因是在乙腈-水混合溶液中,苏丹红Ⅰ, Ⅲ, Ⅳ分子内氢键被破坏,扩大了π键离域范围所致。 相似文献
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Spectroscopic investigations on NO~+(X~1Σ~+, a~3Σ~+, A~1Π) ion using multi-reference configuration interaction method and correlation-consistent sextuple basis set augmented with diffuse functions 下载免费PDF全文
Three low-lying electronic states (X1Σ+, a3Σ+, and A1Π) of NO+ ion are studied using the complete active space self-consistent-field (CASSCF) method followed by highly accurate valence internally contracted multi-reference configuration interaction (MRCI) approach in combination of the correlation-consistent sextuple basis set augmented with diffuse functions, aug-cc-pV6Z. The potential energy curves (PECs) of the NO+(X1Σ+, a3Σ+, A1Π) are calculated. Based on the PECs, the spectroscopic parameters Re, De, ωe, ωeχe, αe, Be, and D0 are reproduced, which are in excellent agreement with the available measurements. By numerically solving the radial Schrdinger equation of nuclear motion using the Numerov method, the first 20 vibrational levels, inertial rotation and centrifugal distortion constants of NO+(X1Σ+, a3Σ+, A1Π) ion are derived when the rotational quantum number J is equal to zero (J = 0) for the first time, which accord well with the available measurements. Finally, the analytical potential energy functions of these states are fitted, which are used to accurately derive the first 20 classical turning points when J = 0. These results are compared in detail with those of previous investigations reported in the literature. 相似文献
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n参数d维随机游动(RW_n~d) 总被引:3,自引:0,他引:3
本文研究了n参数d随机游动(记为RW~d_n)的各种多参数Markov性、单 点转移函数和宽过去转移函数,得到了基本型R叫(B~1(p,q))的一个弱大数定律. 相似文献
88.
采用非同时读出条件下晶体两波耦合实验装置,在入射光调制下,研究了调制频率对Ce:KNSBN晶体两波耦合有效增益(G)的影响,结果显示G随调制频率的增大先增大后减小,但入射光波长不同时,G最大值对应的调制频率不同,入射光波长为632.8nm时,G最大值为20.2,对应的调制频率为100Hz;入射光波长为532nm时,G最大值为15.1,对应的调制频率为175Hz.同时研究了入射光参量对增益改善(Gm/Gf)及最佳调制频率的影响,结果显示不同入射光参量下增益改善及最佳调制频率不同,入射光波长为632.8nm时,增益改善最大为1.92,对应的最佳调制频率为100Hz;入射光波长为532nm时,增益改善最大为1.50,对应的最佳调制频率为150Hz.采用运动光栅理论对实验结果进行了解释. 相似文献
89.
Numerical and experimental study of the mesa configuration in high-voltage 4H–SiC PiN rectifiers 下载免费PDF全文
The effect of the mesa configuration on the reverse breakdown characteristic of a SiC PiN rectifier for high-voltage applications is analyzed in this study.Three geometrical parameters,i.e.,mesa height,mesa angle and mesa bottom corner,are investigated by numerical simulation.The simulation results show that a deep mesa height,a small mesa angle and a smooth mesa bottom(without sub-trench) could contribute to a high breakdown voltage due to a smooth and uniform surface electric field distribution.Moreover,an optimized mesa structure without sub-trench(mesa height of 2.2 μm and mesa angle of 20°) is experimentally demonstrated.A maximum reverse blocking voltage of 4 kV and a forward voltage drop of 3.7 V at 100 A/cm~2 are obtained from the fabricated diode with a 30-μm thick N~- epi-layer,corresponding to 85% of the ideal parallel-plane value.The blocking characteristic as a function of the JTE dose is also discussed for the PiN rectifiers with and without interface charge. 相似文献
90.
研究了火焰光度法测定硼酸盐中钾和钠含量的方法.分别在0~100 mg·L-1和0~200 mg·L-1的浓度范围内,采用差示测量法测定样品中钾和钠含量.考察了硼对钾、钠测定的影响以及钾、钠的相互影响.与四苯硼钠重量法(国家标准)相比,方法测定钾含量相对误差的绝对值≤3.91%,t检验和F检验也表明两种方法无显著性差异.与原子吸收光谱法相比,方法测定钾相对误差的绝对值≤3.63%.测定钠含量相对误差的绝对值≤3.76%,t检验和F检验表明两种方法无显著性差异.钾、钠的加标回收试验结果分别在97.5%~102.5%和97.1%~99.1%之间. 相似文献