Application analysis of efficient heat dissipation of electronic equipment based on flexible nanocomposites

The efficient heat dissipation of electronic equipment is very important,its heat dissipation performance directly determines the life of the equipment itself.A hand-held electronic communications equipment,when used in surface temperature is exorbitant,need to heat dissipation equipment efficiently,to ensure that the use of comfort in the handheld.In accordance with this requirement,this article presents a flexible composite material based on nano-efficient cooling methods that can keep the layout,through the improvement of internal thermal path,it can achieve the effective heat dissipation.The network thermal resistance method is used to analyze the heat transfer in the equipment,and the thermal analysis of the local thermal resistance is carried out.At the same time,through the modeling of electronic equipment and the analysis of finite elements,the temperature drop of the equipment after improvement is accurately judged.Finally,the device experimental performance comparison before and after the optimization of the standby mode and working mode is verified.The results show that the optimized equipment heat source temperature can be reduced by up to 8.5℃,the surface temperature of the equipment can be reduced by about 5℃~7℃,and the final control equipment in the steady standby state of the temperature of about 39±0.5℃,to ensure the comfort of use,and also improved the service life of the equipment.The efficient thermal design of electronic equipment based on flexible nanocomposites can provide a convenient and reliable cooling solution for high-heat flow density devices.

Does Population Aging Hinder the Accumulation of Human Capital?Evidence from China

There is no consensus on the impact of population aging on education investment.To explore this question,we first build an overlapping generations(OLG)model to theoretically analyze the effect of population aging on human capital investment in China,and then test our theory by conducting an empirical study based on micro household data.We find the following.(1)Theoretically,the OLG model shows that population aging has a crowding-out effect on education investment.(2)Empirically,the results show that the share of education and training expenditures decreases by 5.27 percentage points as the ratio of old people in the household increases by 100 percentage points,which confirms the crowding-out effect of population aging on human capital investment.(3)The crowding-out effect is far more intense on urban households than on rural households since health care expenditures will be greater in urban areas as population aging increases.(4)A quantile regression indicates that the negative effect of population aging on the share of educational expenditure is concentrated in households with higher shares of education expenditures.We confirm the robustness of our results using regional fixed effect and instrumental variable(Ⅳ)regressions.