Thermodynamics of electrolytes. X. Enthalpy and the effect of temperature on the activity coefficients

Heat of dilution and of solution data are fitted to the form of equation corresponding to that used successfully for activity and osmotic coefficients over a wide range of concentrations. The resulting parameters give the change with temperature of the activity and osmotic coefficients. Results are reported for 84 electrolytes of 1-1, 2-1, 3-1, and 2-2 valence types.     

One-step estimation for varying coefficient models

A one-step method is proposed to estimate the unknown functions in the varying coefficient models, in which the unknown functions admit different degrees of smoothness. In this method polynomials of different orders are used to approximate unknown functions with different degrees of smoothness. As only one minimization operation is employed, the required computation burden is much less than that required by the existing two-step estimation method. It is shown that the one-step estimators also achieve the optimal convergence rate. Moreover this property is obtained under conditions milder than that imposed in the two-step estimation method. More importantly, as only one minimization operation is employed, the full asymptotic properties, not only the asymptotic bias and variance, but also the asymptotic distributions of the estimators can be derived. The asymptotic distribution results will play a key role for making statistical inference.     

Stability of the Gumowski-Mira equation with period-two coefficient

We investigate the stability of solutions of the Gumowski-Mira equation with a period-two coefficient:

     

Nuclear matter test for a separable non-localN-N interaction

A nuclear matter test has been conducted on a separable non-localN-N interaction proposed by Sirohi and Srivastava. The potential had been constructed by fitting the phase-shifts. The results obtained compare with those obtained by Tabakin in each partial wave. The binding energy per particle and the symmetry energy coefficient obtained are 19.4 MeV and 66.5 MeV respectively atk _F=1.65 fm⁻¹, while the best estimated values for these quantities are 16 MeV and 30–35 MeV atk _F=1.5 fm⁻¹. Single particle potential generated out of this NLSI has in general the same shape as the one obtained through Tabakin potential. Finally as a test of non-locality the integrated photoabsorption cross-section parameterh has been calculated and the value of 1.03 agrees with other reported values.     

On the dependence of the condensation coefficient on surface curvature

It is concluded that there is as yet no adequate theoretical solution for the size dependence of the condensation coefficient, the Okuyama-Zung approach to this problem being discounted.     

Quadrupole interaction of tantalum impurities in bismuth metal

The time differential perturbed angular correlation technique has been used in the measurement of the electric quadrupole interaction of Ta impuritiy in bismuth metal. The interaction frequencies at 293, 400 and 500 K have been observed to be 288±1.5, 266.9±3 and 244.5±4.3 MHz respectively. The electric field gradient at 293 K is 4.75±0.3 × 10¹⁷ V/cm² with the temperature coefficientB=2.2±0.2 × 10⁻⁵ (K)^−3/2.     

Theoretical prediction of maxima in association constants for complex formation between flavin mononucleotide and indoleacetate in the presence of polyelectrolytes

The effects of ionene polymers (6,3-ionene, 6,6-ionene, 6,8-ionene, and 6,12-ionene) with various charge densities upon association constants K for the complexation between flavin mononucleotide and indoleacetate have been studied. Except for 6,12-ionene, K increases with increasing polymer concentration then passes through a maximum, and declines at high polymer concentrations. The value of the maximum K increases in the order 6,8-ionene > 6,3-ionene > 6,6-ionene. In contrast, 6,12-ionene gives only a monotone increasing curve with increasing polymer concentration. These curves are analyzed using the theory of the partition coefficient proposed in the previous paper. The types of the curves that the theory predicts are classified in greater detail than in the previous paper, and examples are given. © 1993 John Wiley & Sons, Inc.     

The method eliminating nearfield effect for measurement sound absorption coefficient

The numerical simulation is used in this work to study the nearfieldradiation pressure of a piston projector,the smooth effect on the pressure fieldby using a“big”receiver and the influence of the nearfield and in the transitionregion on measurement of sound absorption coefficient.The result indicatesthat the big error would appear when using usual absorption coefficientmeasurement method.According to the reason causing the error,the methodeliminating nearfield effect (MENE) is proposed and some digital results aregiven for a/λ=3,9 and b=0,0.5a,a(a and b are the transducer and re-ceiver radii respectively).The calculation results show that the method not onlywidens measurement range in nearfield,but also gives accurate results.     

新型铁电液晶的非线性光学性质的研究

详细研究了两种新型铁电液晶的非线性光学性质，液晶分子倾斜角θｔ、色散折射率，双折射率，双轴折射率和非线性光学系数各分量ｄｉｊ，两次谐波信号强度受外加电场及温度的影响，并分析了液晶分子结构与非线性光学性质的关系。     

Study of asymmetric wavenumber shift of the Fermi doublet ν1 − 2ν2 in the Raman spectrum of liquid carbon disulfide

The Raman spectra of liquid carbon disulfide (CS₂) diluted with benzene (C₆H₆) have been measured. By changing the CS₂, the concentration, we found an asymmetric wavenumber shift phenomenon. With decreasing concentration of CS₂, the position of the ν₁ (655 cm⁻¹) band remains practically unchanged, and the 2ν₂ (796 cm⁻¹) band shifts toward higher wavenumbers. To interpret this asymmetric wavenumber shift phenomenon of the Fermi doublet ν₁ − 2ν₂ in the Raman spectra satisfactorily, we propose a modified Bertran model. The values of the Fermi resonance (FR) parameters of CS₂ at different concentrations were calculated using the Bertran equations. In addition, we found the fundamental ν₂, which should be independent of the FR interaction, shifted to higher wavenumbers as the concentration decreased. This shift was probably driven by the tuning of the FR. Copyright © 2009 John Wiley & Sons, Ltd.