Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sen...Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sensing component,the output current is adjusted to achieve a set temperature.However,the temperature of the heating film is nonuniformly distributed,and determining the correct output current is time-consuming.This study adopted finite element heat transfer analysis to determine a heating method(such as heat power and heat flux)for an ITO conductive heating film system.The results of the analysis may serve as a reference for temperature compensation in ITO conductive heating films.展开更多
Recovering the waste heat(WH)of a power plant can conserve energy and reduce emissions.Scholars have proposed utilizing the WH of power plants in a combined heat and water(CHW)system,which is considered an economical,...Recovering the waste heat(WH)of a power plant can conserve energy and reduce emissions.Scholars have proposed utilizing the WH of power plants in a combined heat and water(CHW)system,which is considered an economical,energy-saving,and environment-friendly way to integrate water and heat supply into long-distance transportation in urban areas of northern China.However,to date,a detailed design of the case on the heat source side of the CHW has not been developed.Therefore,in this study,the heat source side of a CHW system was divided into two cases:a single-generator set and a double-generator set,and both cases were optimized.The parameters of a multi-effect desalination(MED)process were examined;the optimal number of evaporation stages during the MED process was 12,and the optimal heat source temperature during the first stage was 700C.Then,by matching the extraction and exhaust steam flows,the WH of the exhaust steam in the heating season was finally utilized.Further,under each case optimal conditions,energy,exergy,and cost were analyzed.The results showed that the exergy efficiency in the heating season for each case was approximately 50%,whereas that in the non-heating season was approximately 3.5%.The economy and water quality of the single-generator case were better than those of the double-generator case.However,the absorption heat pump required in the single-generator case is difficult to realize because it operates under two working conditions.展开更多
We investigate the temperature dependence of the emission spectrum of a laser-induced semiconductor(Ge and Si) plasma. The change in spectral intensity with the sample temperature indicates the change of the laser a...We investigate the temperature dependence of the emission spectrum of a laser-induced semiconductor(Ge and Si) plasma. The change in spectral intensity with the sample temperature indicates the change of the laser ablation mass. The reflectivity of the target surface is reduced as the sample is heated, which leads to an increase in the laser energy coupled to the surface of the sample and eventually produces a higher spectral intensity.The spectral intensities are enhanced by a few times at high temperatures compared with the cases at low temperatures. The spectral intensity of Ge is enhanced by 1.5 times at 422.66 nm, and 3 times at589.33 nm when the sample temperature increases from 50°C to 300°C. We can obtain the same emission intensity by a more powerful laser or by less pulse energy with a higher sample temperature. Based on experimental observations we conclude that the preheated sample can improve the emission intensity of laser-induced semiconductor plasma spectroscopy.展开更多
文摘Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sensing component,the output current is adjusted to achieve a set temperature.However,the temperature of the heating film is nonuniformly distributed,and determining the correct output current is time-consuming.This study adopted finite element heat transfer analysis to determine a heating method(such as heat power and heat flux)for an ITO conductive heating film system.The results of the analysis may serve as a reference for temperature compensation in ITO conductive heating films.
基金This work was supported by the 13th Five-Year National Key Technology R&D Program of China(No.2019YFE0193200)the Natural Science Foundation of China(No.51521005).
文摘Recovering the waste heat(WH)of a power plant can conserve energy and reduce emissions.Scholars have proposed utilizing the WH of power plants in a combined heat and water(CHW)system,which is considered an economical,energy-saving,and environment-friendly way to integrate water and heat supply into long-distance transportation in urban areas of northern China.However,to date,a detailed design of the case on the heat source side of the CHW has not been developed.Therefore,in this study,the heat source side of a CHW system was divided into two cases:a single-generator set and a double-generator set,and both cases were optimized.The parameters of a multi-effect desalination(MED)process were examined;the optimal number of evaporation stages during the MED process was 12,and the optimal heat source temperature during the first stage was 700C.Then,by matching the extraction and exhaust steam flows,the WH of the exhaust steam in the heating season was finally utilized.Further,under each case optimal conditions,energy,exergy,and cost were analyzed.The results showed that the exergy efficiency in the heating season for each case was approximately 50%,whereas that in the non-heating season was approximately 3.5%.The economy and water quality of the single-generator case were better than those of the double-generator case.However,the absorption heat pump required in the single-generator case is difficult to realize because it operates under two working conditions.
基金supported by the National Natura Science Foundation of China(Nos.11674128,11474129and 11504129)the National 973 Program of China(No.2013CB922200)the China Postdoctoral Science Foundation(No.2014M551169)
文摘We investigate the temperature dependence of the emission spectrum of a laser-induced semiconductor(Ge and Si) plasma. The change in spectral intensity with the sample temperature indicates the change of the laser ablation mass. The reflectivity of the target surface is reduced as the sample is heated, which leads to an increase in the laser energy coupled to the surface of the sample and eventually produces a higher spectral intensity.The spectral intensities are enhanced by a few times at high temperatures compared with the cases at low temperatures. The spectral intensity of Ge is enhanced by 1.5 times at 422.66 nm, and 3 times at589.33 nm when the sample temperature increases from 50°C to 300°C. We can obtain the same emission intensity by a more powerful laser or by less pulse energy with a higher sample temperature. Based on experimental observations we conclude that the preheated sample can improve the emission intensity of laser-induced semiconductor plasma spectroscopy.