The Newtonian heating effects in the stagnation point flow of a Burgers fluid are addressed in this paper. The boundary layer flow problems are stated in the spatial domain from zero to infinity. The solution expressi...The Newtonian heating effects in the stagnation point flow of a Burgers fluid are addressed in this paper. The boundary layer flow problems are stated in the spatial domain from zero to infinity. The solution expressions for the velocity and the temperature are obtained and examined for the influential variables. The tabulated values show comparison with the previous results. It is observed that the obtained results are in good agreement with the existing results in limiting sense.展开更多
A first-principles technique capable of describing the nearly excited states of semiconductors and insulators,namely the modified Becke–Johnson(mBJ)potential approximation,is used to investigate the electronic band s...A first-principles technique capable of describing the nearly excited states of semiconductors and insulators,namely the modified Becke–Johnson(mBJ)potential approximation,is used to investigate the electronic band structure and optical properties of spinel oxides:GeZn_(2)O_(4).The predicted band gaps using the mBJ approximation are significantly more accurate than the proposed previous theoretical work using the common LDA and GGA.Band gap dependent optical parameters,like the dielectric constant,index of refraction,reflectivity and optical conductivity are calculated and analyzed.The results from the dielectric constant shows that the numerical value of the static dielectric,after dropping constantly,becomes less than zero and the material exhibits metallic behavior.The refractive index also drops below unity for photons higher than 18 eV,which indicates that the velocities of incident photons are greater than the velocity of light.However,these phenomena can be explained by the fact that a signal must be transmitted as a wave packet rather than a monochromatic wave.This comprehensive theoretical study of the optoelectronic properties predicts that these materials can effectively be used in optical devices.展开更多
Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors...Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors have not been explored much.This liquid has shown the potentiality of sensitivity to low-mass dark matter.The previous calibration of this liquid was carried out with the poly-energetic neutrons.Purpose In the present work,to better characterize the detector with neutrons,it is irradiated with quasi-mono-energetic neutrons and the results are compared with neutrons from ^(241)Am-Be.To run the detector for the dark matter search,it is required to calibrate it with neutrons,preferably with mono-energetic neutrons.But mono-energetic neutron is not available at all establishments;hence,it was calibrated with quasi-mono-energetic neutrons.Method The response of superheated emulsion consisting of the droplets of C_(2)H_(2)F_(4)has been studied using the quasi-mono-energetic neutrons.The superheated droplets have been fabricated in a visco-elastic gel matrix.The shock waves generated by the passage of the energetic particles are detected by the acoustic sensors coupled to the emulsion.The measurement has also been carried out for the blank target and beam-off conditions.Results and conclusion It is observed that the(P_(var))response of the emulsion in the low-frequency range is sharper for the quasi-mono-energetic neutrons from ^(7)Li(p,n)reaction and wider for the poly-energetic neutrons from ^(241)Am-Be.The fundamental frequency associated with bubble nucleation(FF values)is similar for the neutrons from ^(7)Li-target and ^(241)Am-Be source.The precise characterization of such detector is required for the application in neutron measurement as well as for the dark matter search experiment apart from the basic understanding of the radiation-induced bubble nucleation.展开更多
文摘The Newtonian heating effects in the stagnation point flow of a Burgers fluid are addressed in this paper. The boundary layer flow problems are stated in the spatial domain from zero to infinity. The solution expressions for the velocity and the temperature are obtained and examined for the influential variables. The tabulated values show comparison with the previous results. It is observed that the obtained results are in good agreement with the existing results in limiting sense.
文摘A first-principles technique capable of describing the nearly excited states of semiconductors and insulators,namely the modified Becke–Johnson(mBJ)potential approximation,is used to investigate the electronic band structure and optical properties of spinel oxides:GeZn_(2)O_(4).The predicted band gaps using the mBJ approximation are significantly more accurate than the proposed previous theoretical work using the common LDA and GGA.Band gap dependent optical parameters,like the dielectric constant,index of refraction,reflectivity and optical conductivity are calculated and analyzed.The results from the dielectric constant shows that the numerical value of the static dielectric,after dropping constantly,becomes less than zero and the material exhibits metallic behavior.The refractive index also drops below unity for photons higher than 18 eV,which indicates that the velocities of incident photons are greater than the velocity of light.However,these phenomena can be explained by the fact that a signal must be transmitted as a wave packet rather than a monochromatic wave.This comprehensive theoretical study of the optoelectronic properties predicts that these materials can effectively be used in optical devices.
文摘Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors have not been explored much.This liquid has shown the potentiality of sensitivity to low-mass dark matter.The previous calibration of this liquid was carried out with the poly-energetic neutrons.Purpose In the present work,to better characterize the detector with neutrons,it is irradiated with quasi-mono-energetic neutrons and the results are compared with neutrons from ^(241)Am-Be.To run the detector for the dark matter search,it is required to calibrate it with neutrons,preferably with mono-energetic neutrons.But mono-energetic neutron is not available at all establishments;hence,it was calibrated with quasi-mono-energetic neutrons.Method The response of superheated emulsion consisting of the droplets of C_(2)H_(2)F_(4)has been studied using the quasi-mono-energetic neutrons.The superheated droplets have been fabricated in a visco-elastic gel matrix.The shock waves generated by the passage of the energetic particles are detected by the acoustic sensors coupled to the emulsion.The measurement has also been carried out for the blank target and beam-off conditions.Results and conclusion It is observed that the(P_(var))response of the emulsion in the low-frequency range is sharper for the quasi-mono-energetic neutrons from ^(7)Li(p,n)reaction and wider for the poly-energetic neutrons from ^(241)Am-Be.The fundamental frequency associated with bubble nucleation(FF values)is similar for the neutrons from ^(7)Li-target and ^(241)Am-Be source.The precise characterization of such detector is required for the application in neutron measurement as well as for the dark matter search experiment apart from the basic understanding of the radiation-induced bubble nucleation.
