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1.
Transport properties of a binary mixture of CO2-N2 from the pair potential energy functions based on a semi-empirical inversion method 下载免费PDF全文
The potential energy snrface of a CO2-N2 mixture is determined by using an inversion method, together with a new collision integral correlation [J. Phys. Chem. R@ Data 19 1179 (1990)]. With the new invert potential, the transport properties of CO2-N2 mixture are presented in a temperature range front 273.15 K to 3273.15 K at low density by employing the Chapman-Enskog scheme and the Wang Chang-Uhlenbeck de Boer theory, consisting of a viscosity coefficient, a thermal conductivity coefficient, a binary diffusion coefficient, and a thermal diffusion factor. The accuracy of the predicted results is estimated to be 2% for viscosity, 5% for thermal conductivity, and 10% for binary diffusion coefficient. 相似文献
2.
Transport properties of a binary mixture of CO<sub>2</sub>-N<sub>2</sub> from the pair potential energy functions based on a semi-empirical inversion method 下载免费PDF全文
The potential energy surface of a CO 2 –N 2 mixture is determined by using an inversion method, together with a new collision integral correlation [J. Phys. Chem. Ref. Data 19 1179 (1990)]. With the new invert potential, the transport properties of CO2–N2 mixture are presented in a temperature range from 273.15 K to 3273.15 K at low density by employing the Chapman–Enskog scheme and the Wang Chang–Uhlenbeck–de Boer theory, consisting of a viscosity coefficient, a thermal conductivity coefficient, a binary diffusion coefficient, and a thermal diffusion factor. The accuracy of the predicted results is estimated to be 2% for viscosity, 5% for thermal conductivity, and 10% for binary diffusion coefficient. 相似文献
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运用二次组态相关(QCISD)方法,分别选用6-311++G(3df,3pd)和D95(3df,3pd)基组,对BH2和AlH2分子的结构进行了优化计算,得到BH2分子的稳态结构为C2v构型,电子态为2A1、平衡核间距RBH=0.1187nm、键角∠HBH=128.791°、离解能De=3.65eV、基态振动频率ν1(a1)=1020.103cm-1,ν2(a1)=2598.144cm-1,ν3(b2)=2759.304cm-1.AlH2分子的稳态结构也为C2v构型,电子态为2A1、平衡核间距RAlH=0.1592nm、键角∠HAlH=118.095°、离解能De=2.27eV、基态振动频率ν1(a1)=780.81cm-1,ν2(a1)=1880.81cm-1,ν3(b2)=1910.46cm-1.采用多体项展式理论推导了基态BH2和AlH2分子的解析势能函数,其等值势能图准确再现了BH2和AlH2分子的结构特征及其势阱深度与位置.分析讨论势能面的静态特征时得到BH+H→BH2反应中存在鞍点,活化能为150.204kJ/mol;AlH+H→AlH2反应中也存在鞍点,活化能为54.8064kJ/mol.
关键词:
2')" href="#">BH2
2')" href="#">AlH2
Murrell-Sorbie函数
多体项展式理论
解析势能函数 相似文献
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采用Gaussian 98程序,运用B3LYP方法,对Pd和Pb原子采用收缩价基组LANL2DZ,对Pb2和PdPb2分子的微观结构进行了理论计算. 由于Pb2分子离解后一个Pb原子处于基态,另一个Pb原子处于激发态,采用最小二乘法拟合Pb2分子的势能函数,选用的函数形式为Murrell-Sorbie势能函数加上开关函数. 使用多体展式理论导出了势函数中的参数进而给出PdPb2分子基态势函数的解析表达式,其势能面准确地复现了PdPb2分子的两个稳定构型(C2V和C∞v)及其能量关系.
关键词:
2')" href="#">Pb2
2')" href="#">PdPb2
势能函数 相似文献
6.
G. Garcia-Cosio H. Martinez M. Calixto-Rodriguez A. Gomez 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(18):2787-2793
A low-pressure DC plasma discharge sustained in a 1.6%Ar–2.7%N2–95.3%CO2 ternary mixture is studied. This plasma was generated in a total pressure range from 1.0 to 4.0 Torr, a power of 6.3 W and a 12 l/min flow rate of gases. The electron temperature was found to be 8.41 eV and the ion density, in the order of 109 cm−3. The species observed in the plasma mixture were CO2, CO2+, CN, CO, CO+, O2, O2+, N2, N2+, NO, C+, Ar and Ar+. At the pressure range in the present study, the species observed do not change their intensity due to an increase in the pressure and they separate in two groups according to their emission intensity: the band of the first group (CO2, CO2+ and CN) is approximately a factor of 3 more intense than that of the second group (CO, CO+, O2, O2+, N2, N2+, NO, C+, Ar and Ar+). The behavior of the emission intensities may be correlated to the constant ion density and electron temperature measured. Also, we observed the same constant behavior in the ratios of the neutral and positive species intensities to that of the N2 intensity, as a function of pressure. This may suggest that the different rate coefficients and cross sections of elastic collision, excitation and de-excitation of electronic or vibrational levels, inelastic and superelastic collisions of electrons with the gas phase and products, neutral–neutral interactions, resonant charged transfer processes, recombination, to mention some, to produce these species change in the same proportion, as a function of the pressure to keep the relative ratios of the species almost constant. 相似文献
7.
Rui Zheng 《Journal of Molecular Spectroscopy》2011,265(2):102-105
The rovibrational spectrum of the N2-N2O van der Waals complex has been recorded in the N2O ν1 region (∼1285 cm−1) using a tunable diode laser spectrometer to probe a pulsed supersonic slit jet. The observed transitions together with the data observed previously in the N2O ν3 region are analyzed using a Watson S-reduced asymmetric rotor Hamiltonian. The rotational and centrifugal distortion constants for the ground and excited vibrational states are accurately determined. The band-origin of the spectrum is determined to be 1285.73964(14) cm−1. A restricted two-dimensional intermolecular potential energy surface for a planar structure of N2-N2O has been calculated at the CCSD(T) level of theory with the aug-cc-pVDZ basis sets and a set of mid-bond functions. With the intermolecular distance fixed at the ground state value R = 3.6926 Å, the potential has a global minimum with a well depth of 326.64 cm−1 at θN2 = 11.0° and θN2O = 84.3° and has a saddle point with a barrier height of 204.61 cm−1 at θN2 = 97.4° and θN2O = 92.2°, where θN2(θN2O) is the enclosed angle between the N-N axis (N-N-O axis) and the intermolecular axis. 相似文献
8.
Aniruddha Kumar J.P. NilayaD.J. Biswas R.B. BhattMohd. Afzal J.P. PanakkalH.S. Kamath 《Applied Surface Science》2011,257(16):7263-7267
Pulsed laser assisted removal of uranium dioxide and thorium dioxide particulates from stainless steel surface have been studied using a TEA CO2 laser. Decontamination efficiency is measured as a function of laser fluence and number of pulses. Threshold fluence for the removal of UO2 particulates has been found to be lower than that required for the removal ThO2 particulates. Usage of a ZnSe substrate, that is transparent to the laser wavelength used here, enabled us to decouple the cleaning effect arising out of absorption in the particulates from that in the substrate and has contributed towards understanding the mechanism responsible for cleaning. The experimental observations are also corroborated by simple theoretical calculations. 相似文献
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用Gaussian09程序包的密度泛函理论DFT方法,在BP86/6-311++g(d,p)水平上对O2, TiO和TiO2 分子进行了优化.得到该系列分子的基态电子态分别为:O2(X3Σg), TiO(X3Πg), TiO2(X1 A1), TiO2分子的稳定构型为C2v构型. 用Murrell-Sorbie势能函数对TiO和O2分子的扫描势能点进行拟合, 其扫描点都与四参数Murrell-Sorbie函数拟合曲线符合得很好,在此基础上推导出它们的光谱数据和力常数. 用多体项展开理论导出TiO2分子的全空间解析势能函数,在固定键角∠OTiO=110.5° 的情况下, RTi-O = 0.1652 nm处存在一个深度为15.09 eV的势阱, 表明在该处易形成稳定的TiO2分子.
关键词:
TiO
2和TiO2')" href="#">O2和TiO2
密度泛函理论
势能函数 相似文献
10.
A. Bertolini G. Carelli N. Ioli C. A. Massa J. C. S. Moraes A. Moretti F. Strumia 《International Journal of Infrared and Millimeter Waves》1997,18(4):779-783
Twenty-five new laser lines have been obtained in the wavelength region from 155 to 830 μm by optically pumping the CD2Cl2 (deuterated dichloromethane) molecule with a CW CO2 laser having a tunability range of 300 MHz. The wavelength, polarization relative to that of CO2 pumping radiation, and offset relative to the CO2 center frequency were determined for all of the new lines and some other already known laser emissions. For all of them we
give also the relative intensity and the optimum pressure of operation.
Permanent address: Depto de Física e Química da FEIS — UNESP 15.378-000 Ilha Solteira-SP, Brazil 相似文献
11.
Using a high-resolution tunable diode laser photoacoustic spectrometer, self-, N2 and O2 pressure broadening coefficients for the first 11 transitions of 12C16O2 in the R branch of the (30012) ← (00001) overtone band at the 6348 cm−1 have been revisited at room temperature (∼298 K). Air-broadening parameters have also been calculated from the N2 and O2 measurements. The dependence of the broadening on rotational quantum number m is discussed. The recorded lineshapes are fitted with standard Voigt line profiles in order to determine the collisional broadening coefficients of carbon dioxide transitions. The results are compared to our previous measurements and to the values reported in the HITRAN04 database and by other research group with a different spectroscopic technique. 相似文献
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The density functional calculations on the structural and electronic properties of the endohedral fullerene dimer (N2@C60)2 下载免费PDF全文
The generalised gradient approximation based on density functional theory is used to study the structural and electronic properties of the endohedral fullerene dimer (N 2 @C 60) 2.Four N atoms sit at the cage centres in the form of two N 2 molecules.The density of states and Mulliken charge analysis explore that the energy levels from-6 to-10 eV are mainly influenced by the N 2 molecules. 相似文献
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M. Boutinguiza J. Pou F. Lusquios F. Quintero R. Soto M. Prez-Amor K. Watkins W. M. Steen 《Optics and Lasers in Engineering》2002,37(1)
Slate is a natural stone which has the characteristic that shows a well-developed defoliation plane, allowing to easily split it in plates parallel to that plane which are particularly used as tiles for roof building. At present, the manufacturing of slate is mostly manual, being noisy, powdery and unsafe for the worker. Thus, there is a need to introduce new processing methods in order to improve both the working conditions and the quality of the products made of slate.Following the previous work focused on the drilling and cutting of slate tiles using a Nd : YAG laser, we present in this paper the results of the work carried out to explore the possibilities to cut slate plates by using a CO2 laser. A 1.5 kW CO2 laser was used to perform different experiments in which, the influence of some processing parameters (average power, assist gas pressure) on the geometry and quality of the cut was studied. The results obtained show that the CO2 laser is a feasible tool for a successful cutting of slate. 相似文献
15.
A Teller–Landau six-temperature model describing the dynamic emission of single-mode TEA CO2 laser has been adapted. This model has been also used to describe the mechanism of obtaining relatively high-power output pulses from hybrid TE-TEA or CW-TEA CO2 laser consisting of high- and low-pressure sections. The suggested mathematical model allows to investigate the mechanism which limits the TEA oscillation to single longitudinal mode (SLM) due to the narrow gain bandwidth of low-pressure section, and also to study the effect of the laser input parameters on the smooth output laser pulse parameters. In addition, numerical solutions of non-linear rate equation system of the suggested model are quantitatively discussed. The solutions describe the radiation field intensity, the population inversion, and the energy transfer processes. The calculated values of maximum peak power, total energy in pulse, pulse width, etc. are in a very good agreement with the observed experimental values. 相似文献
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We have developed a 1-D spatially-dependent model and simulation code to study the dynamics of TEA CO2 lasers. In this paper we will discuss the motivation for developing the model and present the simulation details. We have compared and verified the simulation results with the previous 0-D model, and with the measurements of a TEA CO2 laser. With spatial resolution, the 1-D simulation is in better agreement with experimental results compared with the existing 0-D model. 相似文献
17.
M. Abu-Kharma 《Journal of Molecular Spectroscopy》2005,232(2):369-374
Enhancement spectra of the collision-induced absorption (CIA) in the first overtone region 5000-7000 cm−1 of D2 in D2-N2 were studied at 298 K for a base density of D2 of 73 amagat and for partial densities of N2 in the range 150-370 amagat. The observed spectra were modeled with a total of 1176 components of double vibrational transitions. Binary and ternary absorption coefficients were determined from the integrated absorption of the band. Profile analysis of the spectra was carried out using the Birnbaum-Cohen line-shape function for the individual components of the band, and characteristic line-shape parameters were determined from the analysis. Good agreement was obtained between the experimental and calculated spectral profiles. 相似文献
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The equilibrium structure of flue gas SO2 is optimized using the density functional theory (DFT)/B3P86 method and CC-PV5Z basis. The result shows that it has a bent (C2v, X1A1) ground state structure with an angle of 119.1184°. The vibronic frequencies and the force constants are also calculated. Based on the principles of atomic and molecular reaction statics (AMIIS), the possible electronic states and reasonable dissociation limits for the ground state of SO2 molecule are determined. The potential functions of SO and 02 are fitted by the modified Murrell-Sorbie+c6 (M-S+c6) potential function and the fitted parameters, the force constants and the spectroscopic constants are obtained, which are all close to the experimental values. The analytic potential energy function of the SO2 (X1A1) molecule is derived using the many-body expansion theory. The contour liues are constructed, which show the static properties of SO2 (XIA1), such as the equilibrium structure, the lowest energies, the most possible reaction channel, etc. 相似文献
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In a research of fast axial flow CO2 laser sustained by 150 kHz silent discharge, we found the optimized gas mixing ratio was CO2:N2:He=1:22:5 or the content of helium was only about 18%. This result upset the situation of common CO2 lasers in which the most important laser gas is helium. An explanation of our particular results and supporting experimental evidence are given. 相似文献