The nano particles have demonstrated great potential to improve the heat transfer characteristics of heat transfer fluids.Possible parameters responsible for this increase were studied. The heat transfer profile in th...The nano particles have demonstrated great potential to improve the heat transfer characteristics of heat transfer fluids.Possible parameters responsible for this increase were studied. The heat transfer profile in the nanolayer region was combined with other parameters such as volume fraction, particle radius thermal conductivity of the fluid, particle and nanolayer, to formulate a thermal conductivity model. Results predicting the thermal conductivity of nanofluids using the model were compared with experimental results as well as studies by other researchers. The comparison of the results obtained for the Cu O/water and Ti O2/water nanofluids studied shows that the correlation proposed is in closest proximity in predicting the experimental results for the thermal conductivity of a nanofluid. Also, a parametric study was performed to understand how a number of factors affect the thermal conductivity of nanofluids using the developed correlation.展开更多
Based on a new perspective of industry chain and selecting monthly data from February2006to December2015,this paper chooses eight Chinese industrial sectors to construct a SVAR model reflecting internal relationships ...Based on a new perspective of industry chain and selecting monthly data from February2006to December2015,this paper chooses eight Chinese industrial sectors to construct a SVAR model reflecting internal relationships among metal chains,analyzes the direct effects and indirect effects of international metal prices on output of various links in metal chains,then it investigates the main transmission path of international metal price shocks through decomposing the inflation pressure sources in metal chains.The results show that international metal price shocks not only affect industrial output in a direct way,but also indirectly affect the growth of output through the increased pressure on industrial inflation and then triggering a tightening of monetary policy implementation.Affected by factors such as the lack of market demand and the price transmission mechanism blocking,the direct effects of international metal price shocks mainly impact the upstream and midstream industry,while the downstream industry is mainly affected by indirect effects;in addition,the international metal price shocks have spillover effects on the industrial inflation,and transmit along the industry chain from upstream to downstream,and their strength weakens in sequence.展开更多
A combined conduction and radiation heat transfer model was used to simulate the heat transfer within wafer and investigate the effect of thermal transport properties on temperature non-uniformity within wafer surface...A combined conduction and radiation heat transfer model was used to simulate the heat transfer within wafer and investigate the effect of thermal transport properties on temperature non-uniformity within wafer surface. It is found that the increased conductivities in both doped and undoped regions help reduce the temperature difference across the wafer surface. However, the doped layer conductivity has little effect on the overall temperature distribution and difference. The temperature level and difference on the top surface drop suddenly when absorption coefficient changes from 104 to 103 m-1. When the absorption coefficient is less or equal to 103 m-1, the temperature level and difference do not change much. The emissivity has the dominant effect on the top surface temperature level and difference. Higher surface emissivity can easily increase the temperature level of the wafer surface. After using the improved property data, the overall temperature level reduces by about 200 K from the basis case. The results will help improve the current understanding of the energy transport in the rapid thermal processing and the wafer temperature monitor and control level.展开更多
A novel periodic mount was presented. A theoretical model was developed to describe the dynamics of wave propagation in the novel periodic mount. The model was derived using Hamilton's energy conservation principl...A novel periodic mount was presented. A theoretical model was developed to describe the dynamics of wave propagation in the novel periodic mount. The model was derived using Hamilton's energy conservation principle. The characteristics of wave propagation in unit cell were analyzed by transfer matrix formulation. Numerical examples were given to illustrate the effectiveness of the periodic mount. The experiments were carried out to identify the predications of the theoretical model. The obtained results show that the experimental results coincide with the prediction of theoretical model. No pass bands appear in the overall frequency range measured when waves propagate in the longitude direction of the periodic mount. These dramatic results demonstrate its potential as an excellent mount in attenuating and isolating vibration transmission.展开更多
文摘The nano particles have demonstrated great potential to improve the heat transfer characteristics of heat transfer fluids.Possible parameters responsible for this increase were studied. The heat transfer profile in the nanolayer region was combined with other parameters such as volume fraction, particle radius thermal conductivity of the fluid, particle and nanolayer, to formulate a thermal conductivity model. Results predicting the thermal conductivity of nanofluids using the model were compared with experimental results as well as studies by other researchers. The comparison of the results obtained for the Cu O/water and Ti O2/water nanofluids studied shows that the correlation proposed is in closest proximity in predicting the experimental results for the thermal conductivity of a nanofluid. Also, a parametric study was performed to understand how a number of factors affect the thermal conductivity of nanofluids using the developed correlation.
基金Projects(71633006,71573282)supported by the National Natural Science Foundation of China
文摘Based on a new perspective of industry chain and selecting monthly data from February2006to December2015,this paper chooses eight Chinese industrial sectors to construct a SVAR model reflecting internal relationships among metal chains,analyzes the direct effects and indirect effects of international metal prices on output of various links in metal chains,then it investigates the main transmission path of international metal price shocks through decomposing the inflation pressure sources in metal chains.The results show that international metal price shocks not only affect industrial output in a direct way,but also indirectly affect the growth of output through the increased pressure on industrial inflation and then triggering a tightening of monetary policy implementation.Affected by factors such as the lack of market demand and the price transmission mechanism blocking,the direct effects of international metal price shocks mainly impact the upstream and midstream industry,while the downstream industry is mainly affected by indirect effects;in addition,the international metal price shocks have spillover effects on the industrial inflation,and transmit along the industry chain from upstream to downstream,and their strength weakens in sequence.
基金Project(N110204015)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2012M510075)supported by the China Postdoctoral Science Foundation
文摘A combined conduction and radiation heat transfer model was used to simulate the heat transfer within wafer and investigate the effect of thermal transport properties on temperature non-uniformity within wafer surface. It is found that the increased conductivities in both doped and undoped regions help reduce the temperature difference across the wafer surface. However, the doped layer conductivity has little effect on the overall temperature distribution and difference. The temperature level and difference on the top surface drop suddenly when absorption coefficient changes from 104 to 103 m-1. When the absorption coefficient is less or equal to 103 m-1, the temperature level and difference do not change much. The emissivity has the dominant effect on the top surface temperature level and difference. Higher surface emissivity can easily increase the temperature level of the wafer surface. After using the improved property data, the overall temperature level reduces by about 200 K from the basis case. The results will help improve the current understanding of the energy transport in the rapid thermal processing and the wafer temperature monitor and control level.
基金Project(50775225) supported by the National Natural Science Foundation of China
文摘A novel periodic mount was presented. A theoretical model was developed to describe the dynamics of wave propagation in the novel periodic mount. The model was derived using Hamilton's energy conservation principle. The characteristics of wave propagation in unit cell were analyzed by transfer matrix formulation. Numerical examples were given to illustrate the effectiveness of the periodic mount. The experiments were carried out to identify the predications of the theoretical model. The obtained results show that the experimental results coincide with the prediction of theoretical model. No pass bands appear in the overall frequency range measured when waves propagate in the longitude direction of the periodic mount. These dramatic results demonstrate its potential as an excellent mount in attenuating and isolating vibration transmission.
