Based on Onsager and Onsager-Fuoss-Chen equations of conductance,a new prediction equation is proposed for dilute electrolyte solution. It is used to predict and calculate the conductance of some single strong electro...Based on Onsager and Onsager-Fuoss-Chen equations of conductance,a new prediction equation is proposed for dilute electrolyte solution. It is used to predict and calculate the conductance of some single strong electrolyte solutions and their mixtures at 298.15 K. The results show good agreements with those data from literatureand they are better than those calculated with Onsager limiting equation and two-parameter Onsager-Fuoss-Chen equation. In addition,the new equation can also be used to determine the limiting molar conductivityof strong electrolyte by one-point experimental data of the molar conductivityat a certain concentration.The calculation deviation of the new equation shows a minimum value when the strength of ion in solution approaches 0.001 mol·dm^-3,hence,so long as the molar conductivity near this point is measured,the limitingmolar conductivity can be calculated conveniently and reliably by the new equation.展开更多
Phosphoric acid and its acidic sodium salts are unsymmetrical electrolytes. There exist dissociation and association equilibria among the species of these electrolytes in aqueous solutions. The molar conductivity of s...Phosphoric acid and its acidic sodium salts are unsymmetrical electrolytes. There exist dissociation and association equilibria among the species of these electrolytes in aqueous solutions. The molar conductivity of solution is equal to the sum of the ionic contributions. The molar conductivities of the solution and relevant ions were calculated respectively by using a new prediction equation of ionic conductivity proposed in a previous paper of the authors.The results calculated from the new equation were in good agreement with those from literature and the four-parameter Quint-Viallard’s conductance equation.展开更多
A stochastic model of conducting crack propagation is presented to provide a conceptual framework dedicated to the study of the formation of fractal structure of dielectric ageing patterns as a result of a competition...A stochastic model of conducting crack propagation is presented to provide a conceptual framework dedicated to the study of the formation of fractal structure of dielectric ageing patterns as a result of a competition between random fluctuation growth and applied electric strength enhanced deterministic growth. The necessary and sufficient conditions resulting in fractal behaviour in dielectric ageing are found.展开更多
The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples...The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples, and quartz-matrix samples with variable laminated shale, dispersed shale, and pyrite content and then perform petrophysics experiments to assess the effect of pyrite content on the conductivity of pyrite-bearing shaly sands. Second, based on the differences in conductivity and conduction pathways and geometries because of the variable composition of the pyrite-bearing laminated and dispersed shaly sands, we divide the shaly sands into their components, i.e., laminated shale, quartz grains, pyrite grains, hydrocarbon, dispersed shale, microscopic capillary water, and mobile water. A generalized resistivity model is proposed to describe the conductivity of pyrite- bearing laminated and dispersed shaly sands, based on the combined conductivity differential equation and generalized Archie equation. In the generalized resistivity model, the conductivity differential equation is used to describe the conductivity of dispersed inclusions in a host, whereas the generalized Archie equation is used to describe the conductivity of two conducting phases. Moreover, parallel conductance theory is used to describe the conductivity of dispersed shaly sands and laminated shale. Theoretical analysis suggests that the proposed model satisfies the physical constraints and the model and experimental results agree. The resistivity and resistivity index of shaly sands decrease with increasing conductivity and pyrite. Finally, the accuracy of the resistivity model is assessed based on experimental data from 46 synthetic core samples with different oil saturation. The model can describe the conductivity of clean pyrite-matrix samples, and quartz-matrix samples with different volumes of laminated shale, dispersed shale, and pyrite. An accurate saturation model of pyrite-bearing laminated and dispersed shaly sands is thus obtained and the log data interpretation in complex shaly sands can improve with the proposed model.展开更多
The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electri...The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electric conductivity during aging were established for Cu-Ni-Si alloys,on the basis of linear relationship between the electric conductivity and the volume fraction of precipitates,and the calculation results coincide well with the experiment ones.The transformation kinetics curves were established to characterize the aging process.The characteristics of precipitates in the supersaturated solid solution alloy aged at 723 K were established,and the results show that the precipitates areβ-Ni3Si andδ-Ni2Si phases.展开更多
Frequency and temperature dependent dielectric dispersion of 20PbF2？20TeO2？（60？x）B2O3？xEu2O3（x=0 to 2.5, mole fraction, %） glasses prepared by the melt？quenching technique were investigated in the frequency r...Frequency and temperature dependent dielectric dispersion of 20PbF2？20TeO2？（60？x）B2O3？xEu2O3（x=0 to 2.5, mole fraction, %） glasses prepared by the melt？quenching technique were investigated in the frequency range 1 Hz？10 MHz and temperature range 313？773 K. Dielectric relaxation dynamics was analyzed based on the electric modulus behavior. Dielectric losses （tanδ） are found to be negligibly small in the temperature range 313？523 K, proving good thermal stability of the glasses. The present Eu2O3-doped oxyfluroborate glasses showed low dielectric loss at higher frequency and lower temperature, proving their suitability for nonlinear optical materials.展开更多
In this paper, based on the Schrfdinger equation and the ψ mapping theory, the accurate expression for the gradient of resonating valence bond superconducting phase Θ^2s is found. The expression of Δ↓Θ^2s is just...In this paper, based on the Schrfdinger equation and the ψ mapping theory, the accurate expression for the gradient of resonating valence bond superconducting phase Θ^2s is found. The expression of Δ↓Θ^2s is just the velocity flow without considering the coefficient. The curl of Δ↓Θ^2s is where the vortex lies, and has important relation to δ2（ψ） and an important relation to the zero points of resonating valence bond superconducting order parameter ψ. The topological structure of the vortex is characterized by the ψ-mapping topological numbers Hopf-index and Brouwer degrees. The Ginzberg-Landau equation in resonating valence bond state also is discussed in this theory. The magnetic property is discussed also.展开更多
文摘Based on Onsager and Onsager-Fuoss-Chen equations of conductance,a new prediction equation is proposed for dilute electrolyte solution. It is used to predict and calculate the conductance of some single strong electrolyte solutions and their mixtures at 298.15 K. The results show good agreements with those data from literatureand they are better than those calculated with Onsager limiting equation and two-parameter Onsager-Fuoss-Chen equation. In addition,the new equation can also be used to determine the limiting molar conductivityof strong electrolyte by one-point experimental data of the molar conductivityat a certain concentration.The calculation deviation of the new equation shows a minimum value when the strength of ion in solution approaches 0.001 mol·dm^-3,hence,so long as the molar conductivity near this point is measured,the limitingmolar conductivity can be calculated conveniently and reliably by the new equation.
文摘Phosphoric acid and its acidic sodium salts are unsymmetrical electrolytes. There exist dissociation and association equilibria among the species of these electrolytes in aqueous solutions. The molar conductivity of solution is equal to the sum of the ionic contributions. The molar conductivities of the solution and relevant ions were calculated respectively by using a new prediction equation of ionic conductivity proposed in a previous paper of the authors.The results calculated from the new equation were in good agreement with those from literature and the four-parameter Quint-Viallard’s conductance equation.
文摘A stochastic model of conducting crack propagation is presented to provide a conceptual framework dedicated to the study of the formation of fractal structure of dielectric ageing patterns as a result of a competition between random fluctuation growth and applied electric strength enhanced deterministic growth. The necessary and sufficient conditions resulting in fractal behaviour in dielectric ageing are found.
基金This work was supported by the National Natural Science Foundation of China （No. 41274110）, and the Northeast Petroleum University Innovation Foundation for Postgraduate （No. YJSCX2016-003NEPU）.
文摘The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples, and quartz-matrix samples with variable laminated shale, dispersed shale, and pyrite content and then perform petrophysics experiments to assess the effect of pyrite content on the conductivity of pyrite-bearing shaly sands. Second, based on the differences in conductivity and conduction pathways and geometries because of the variable composition of the pyrite-bearing laminated and dispersed shaly sands, we divide the shaly sands into their components, i.e., laminated shale, quartz grains, pyrite grains, hydrocarbon, dispersed shale, microscopic capillary water, and mobile water. A generalized resistivity model is proposed to describe the conductivity of pyrite- bearing laminated and dispersed shaly sands, based on the combined conductivity differential equation and generalized Archie equation. In the generalized resistivity model, the conductivity differential equation is used to describe the conductivity of dispersed inclusions in a host, whereas the generalized Archie equation is used to describe the conductivity of two conducting phases. Moreover, parallel conductance theory is used to describe the conductivity of dispersed shaly sands and laminated shale. Theoretical analysis suggests that the proposed model satisfies the physical constraints and the model and experimental results agree. The resistivity and resistivity index of shaly sands decrease with increasing conductivity and pyrite. Finally, the accuracy of the resistivity model is assessed based on experimental data from 46 synthetic core samples with different oil saturation. The model can describe the conductivity of clean pyrite-matrix samples, and quartz-matrix samples with different volumes of laminated shale, dispersed shale, and pyrite. An accurate saturation model of pyrite-bearing laminated and dispersed shaly sands is thus obtained and the log data interpretation in complex shaly sands can improve with the proposed model.
基金Project(2006AA03Z517) supported by the National High-tech Research and Development Program of ChinaProject(08MX15) supported by the Mittal Programs of Central South University, China
文摘The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity.The Avrami-equation of phase transformation kinetics and the Avrami-equation of electric conductivity during aging were established for Cu-Ni-Si alloys,on the basis of linear relationship between the electric conductivity and the volume fraction of precipitates,and the calculation results coincide well with the experiment ones.The transformation kinetics curves were established to characterize the aging process.The characteristics of precipitates in the supersaturated solid solution alloy aged at 723 K were established,and the results show that the precipitates areβ-Ni3Si andδ-Ni2Si phases.
基金supported by a grant-in-aid for a scientific research from the Department of Atomic Energy(DAE)-Board of Research in Nuclear Science[S.No.2012/34/17/BRNS]of the Government of India
文摘Frequency and temperature dependent dielectric dispersion of 20PbF2？20TeO2？（60？x）B2O3？xEu2O3（x=0 to 2.5, mole fraction, %） glasses prepared by the melt？quenching technique were investigated in the frequency range 1 Hz？10 MHz and temperature range 313？773 K. Dielectric relaxation dynamics was analyzed based on the electric modulus behavior. Dielectric losses （tanδ） are found to be negligibly small in the temperature range 313？523 K, proving good thermal stability of the glasses. The present Eu2O3-doped oxyfluroborate glasses showed low dielectric loss at higher frequency and lower temperature, proving their suitability for nonlinear optical materials.
文摘In this paper, based on the Schrfdinger equation and the ψ mapping theory, the accurate expression for the gradient of resonating valence bond superconducting phase Θ^2s is found. The expression of Δ↓Θ^2s is just the velocity flow without considering the coefficient. The curl of Δ↓Θ^2s is where the vortex lies, and has important relation to δ2（ψ） and an important relation to the zero points of resonating valence bond superconducting order parameter ψ. The topological structure of the vortex is characterized by the ψ-mapping topological numbers Hopf-index and Brouwer degrees. The Ginzberg-Landau equation in resonating valence bond state also is discussed in this theory. The magnetic property is discussed also.
