Molar extinction coefficients of solutions of some organic compounds

Molar extinction coefficients of aqueous solutions of some organic compounds, viz. formamide (CH₃NO),N-methylformamide (C₂H₅NO),NN-dimethylformamide (C₃H₇NO),NN-dimethylacetamide (C₄H₉NO), 1,4-dioxane (C₄H₈O₂₄), succinimide (C₄H₅NO₂) and solutions of acetamide (C₂H₅NO) and benzoic acid (C₇H₆O₂) in 1,4-dioxane (C₄H₈O₂) have been determined by narrow beam γ-ray transmission method at 81, 356, 511, 662, 1173 and 1332 keV. The experimental values of mass attenuation coefficients of these compounds have been used to calculate effective atomic numbers and electron densities. The additivity rule earlier used for aqueous solution has been extended to non-aqueous (1,4-dioxane) solutions.     

Molar extinction coefficients of IR absorption bands of Cu(II) dipivaloylmethanate

IR absorption spectra of an intracomplex chelate compound of Cu(II) bis-dipivaloylmethanate in the spectral range 4000–300 cm⁻¹ are investigated. A comparison is made between the spectra of the complex in different aggregative states: as a solution in heptane and as condensed films. The molar extinction coefficients of absorption bands are calculated. The extinction coefficients found are used to evaluate the thickness of Cu(dpm)₂ films. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 1, pp. 34–37, January–February, 2000.     

Molar coefficients of extinction for IR absorption bands of Ni(II) acetylacetonate, ketoiminate, and trifluoroacetylacetonate

We have studied IR absorption spectra (within the spectral range of 4000-200 cm⁻¹ of the intracomplex chelate compounds Ni(II) bis-acetylacetonate, Ni(II) bis-ketoiminate, and Ni(II) bis-trifluoroacetylacetonate and have given a full interpretation and comparison of the spectra of these compounds in dissolved and solid states. The reasons for the differences in the spectra are discussed. The molar coefficients of extinction for the absorption bands are calculated. Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3, Akad. Lavrent’ev Ave., Novosibirsk, 630090, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 775–780, September–October, 1998.     

Uncertainty propagation of chemical kinetics parameters and binary diffusion coefficients in predicting extinction limits of hydrogen/oxygen/nitrogen non-premixed flames

A comprehensive investigation of the uncertainties associated with the experimental and numerical evaluation of the extinction strain rate in hydrogen/oxygen/nitrogen non-premixed flames is presented in this work. The reported new experimental uncertainties of the extinction strain rate include several sources of uncertainties that typically affect the characterisation of velocity and boundary conditions of counterflow flames via particle image velocimetry. The uncertainties associated with the numerical determination of the extinction strain rate not only depend upon the selected chemical kinetics parameters but also on the binary diffusion coefficients. In order to identify the major sources of uncertainties in the chemical and diffusion models, a Monte Carlo based high-dimensional model representation analysis of the extinction curve was performed. Independent and simultaneous perturbations of relevant chemical kinetics and diffusion parameters have shown that the uncertainties associated with the binary diffusion coefficients are about a factor of 10 smaller than the uncertainty due to chemical kinetics parameters. Since the experimentally well known binary diffusion coefficient for hydrogen and nitrogen, , accounts for most of the propagated uncertainty of the diffusion model, it is shown here that only a reduction of the uncertainty of chemical kinetics parameters will have a significant impact in improving the accuracy of the extinction strain rate predictions.     

Regaining profiles of extinction coefficients of optically dense scattering media in laser location measurements

We suggest a procedure for regaining spectral values of the extinction coefficients ε(r) of optically dense scattering media in laser location measurements. Allowance is made for the contribution of multiple scattering to a recorded signal and its correction for the degree of change of the qualitative composition of the scattering medium. The procedure can increase the accuracy of regaining ε(r) and eliminate the “edge effect” at the end of the probed path. The latter is achieved by determining a calibration constant from the transparency value of the whole probing range, which is calculated from back-scattered signals corrected based on the constancy of the lidar ratio. We present an algorithm for calculating the correction coefficient. The efficiency of regaining profiles of ε(r) is estimated using the atmospheric situation of a pure atmosphere and an extended smoke cloud arising from forest fires as an example. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 4, pp. 522–527, July–August, 2007.     

Viscosity of aqueous solutions of monocarboxylic acids

An attempt has been undertaken to apply viscosimetric measurements for the examination of incomplete dissociation of symmetric electrolyte solutions. For this purpose precise measurements of the viscosity and density of dilute aqueous solutions of monocarboxylic acids (formic, acetic, propionic and valeric) have been conducted at 298.15 K. Modified Jones–Dole equations have been proposed for incompletely dissociated electrolyte solutions of 1–1 type. The data have been analysed taking into account dimerization of carboxylic acids. The B coefficients for all chemical species in the solution have been determined.     

变系数Burgers方程的分类及相似解(英文)

应用经典李群理论考虑了描述非平面冲击波形成和衰减现象的(1 1)维变系数Burgers方程,得到该方程的群分类及相应的对称.对于某些具体形式的色散项系数a(t)和非线性项系数b(t),给出了对应方程的对称约化及相似解.本文在已有基础上给出了方程新的显式解.这些解对于研究某些复杂的物理现象,以及验证数值求解法则的可行性有重要的意义.     

Optical absorption coefficients in asymmetric quantum well

The optical absorption coefficients considering electron-phonon interaction in asymmetrical quantum wells are theoretically studied. The result shows that the optical absorption coefficients depend strongly on the parameters of quantum well. Interestingly, the theoretical values of the optical absorption coefficients obviously increase with considering the electron-phonon interaction.     

变系数Whitham-Broer-Kaup方程组的对称、约化及精确解

利用修正的Clarkson-Kruskal直接法对变系数Whitham-Broer-Kaup(VCWBK)方程组进行等价转化,建立了VCWBK方程组与常系数WBK方程组解之间的关系,并得到了常系数WBK方程组的一些对称和相似约化.借助辅助函数法得到了VCWBK方程组的一些新精确解,包括有理函数解、双曲函数的解、三角函数解和Jacobi椭圆函数解.     

Electron impact excitation rate coefficients of N II ion

This paper calculates the electron impact excitation rate coefficients from the ground term 2s²2p^{2 3}P to the excited terms of the 2s²2p², 2s2p³, 2s²2p3s, 2s²2p3p, and 2s²2p3d configurations of N II. In the calculations, multiconfiguration Dirac--Fork wave functions have been applied to describe the target-ion states and relativistic distorted-wave calculation has been performed to generate fine-structure collision strengths. The collision strengths are then averaged over a Maxwellian distribution of electron velocities in order to generate the effective collision strengths. The calculated rate coefficients are compared with available experimental and theoretical data, and some good agreements are found for the outer shell electron excitations. But for the inner shell electron excitations there are still some differences between the present calculations and available experiments.     

Determination of aerosol extinction coefficient and mass extinction efficiency by DOAS with a flashlight source

With the method of differential optical absorption spectroscopy （DOAS）, average concentrations of aerosol particles along light path were measured with a flashlight source in Chiba area during the period of one month. The optical thickness at 550 nm is compared with the concentration of ground-measured suspended particulate matter （SPM）. Good correlations are found between the DOAS and SPM data, leading to the determination of the aerosol mass extinction efficiency （MEE） to be possible in the lower troposphere. The average MEE value is about 7.6m^2.g^-1 , and the parameter exhibits a good correlation with the particle size as determined from the wavelength dependence of the DOAS signal intensity.     

摩尔电导率与浓度关系模型的探讨

基于强电解质溶液摩尔电导率实验测定数据的研究 ,提出强电解质在浓度小于 0 .1 0 0 0 mol· L-1 时 ,计算在不同浓度下强电解质的摩尔电导率和极限摩尔电导率的经验方程Λm=Λ0m-α C βC分别对 89种强电解质和 HAc、NH3 · H2 O和 n- HOOCC3 H7弱电解质的极限摩尔电导率进行计算 ,改进后关系模型的计算结果与推荐值能很好的吻合 ,总体误差小于科尔劳乌施经验方程。在电导测定应用研究中 ,简化了实验数据过程 ,结果更准确、更可靠。     

Invariance of activity coefficients for the hydrogen ion with charge-type of fluorescent indicators in aqueous-methanol solutions

Steady-state fluorimetric pH titrations of three fluorescent indicators of differing charge-type were carried out in aqueous methanol solutions containing up to 64 mol% methanol. The plot of the ratio of the relative fluorescence efficiency of the indicator acid to that of its conjugate base versus the product of the formal hydrogen ion concentration and the appropriate Bronsted kinetic activity factor gives straight lines for titrations in each mixed solvent, just as it does in water, but only if the constant terms in the Bronsted factor are modified to account for the bulk dielectric constant in each solvent. The product of the formal charges on the proton and the particular conjugate base studied in each titration must also be included in the Bronsted factor. This supports the hypothesis that a valid operational pH can be defined and kinetic parameters related to proton transfer can be extracted from the fluorimetric titrations in mixed solvents.     

Soliton solutions of some nonlinear evolution equations with time-dependent coefficients

In this paper, we obtain exact soliton solutions of the modified KdV equation, inhomogeneous nonlinear Schrödinger equation and G(m, n) equation with variable-coefficients using solitary wave ansatz. The constraint conditions among the time-dependent coefficients turn out as necessary conditions for the solitons to exist. Numerical simulations for dark and bright soliton solutions for the mKdV equation are also given.     

A new method of new exact solutions and solitary wave-like solutions for the generalized variable coefficients Kadomtsev——Petviashvili equation

Using the solution of general Korteweg--de Vries (KdV) equation, the solutions of the generalized variable coefficient Kadomtsev--Petviashvili (KP) equation are constructed, and then its new solitary wave-like solution and Jacobi elliptic function solution are obtained.     

类镍钆(Gd36+)离子的双电子复合系数研究

 在自旋轨道劈裂阵模型下,通过类铜组态理论计算出类镍Gd³⁶⁺的双电子复合速率系数,得出其在电子温度 0.02~5keV 范围内的变化规律,并分析了影响双电子复合速率系数的主要因素是相应的自电离系数和离化势,这为等离子体的诊断提供了一种新的方法。     

类镍钆(Gd36+)离子的双电子复合系数研究

在自旋轨道劈裂阵模型下,通过类铜组态理论计算出类镍Gd36+的双电子复合速率系数,得出其在电子温度 0.02~5keV 范围内的变化规律,并分析了影响双电子复合速率系数的主要因素是相应的自电离系数和离化势,这为等离子体的诊断提供了一种新的方法。     

类铜Dy37+离子的双电子复合速率研究

在自旋轨道劈裂阵模型(SOSA)下,通过类锌组态,理论计算出类铜Dy37+的双电子复合速率系数,得出其在电子温度0.02 keV～5.0 keV范围内的变化规律,分析了不同离化度离子的能级特征,并分析了影响双电子复合速率系数的主要因素是相应的中间自电离态旁观电子主量子数、旁观电子角动量和电离能,这为实现等离子体的诊断提供了重要的参数.