The safety problems encountered with lithium–sulfur batteries(LSBs)hinder their development for practical applications.Herein,a highly thermally conductive separator was constructed by cross‐weaving super‐aligned c...The safety problems encountered with lithium–sulfur batteries(LSBs)hinder their development for practical applications.Herein,a highly thermally conductive separator was constructed by cross‐weaving super‐aligned carbon nanotubes(SA‐C)on super‐aligned boron nitride@carbon nanotubes(SA‐BC)to create a composite film(SA‐BC/SA‐C).This separator was used to fabricate safe LSBs with improved electrochemical performance.The highly aligned separator structure created a uniform thermal field that could rapidly dissipate heat accumulated during continuous operation due to internal resistance,which prevented the development of extremely high temperatures.The array of boron nitride nanosheets endowed the composite separator with a large number of adsorption sites,while the highly graphitized carbon nanotube skeleton accelerated the catalytic conversion of high‐valence polysulfides into low‐valence polysulfides.The arrayed molecular brush design enabled the regulation of local current density and ion flux,and considerably alleviated the growth of lithium dendrites,thus promoting the smooth deposition of Li metal.Consequently,a battery constructed with the SA‐BC/SA‐C separator showed a good discharge capacity of 685.2 mAh g−1 over 300 cycles(a capacity decay of 0.026%per cycle)at 2 C and 60°C.This“three‐in‐one”multifunctional separator design strategy constitutes a new path forward for overcoming the safety problems of LSBs.展开更多
Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30...Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30% in a primary network when under a partial load. Through deducing and optimizing an exponential function flow regulation rule, the formulae of flow regulation and the supply and return water temperatures are obtained, and their relevant curves are plotted. After comparison, it is found that this control method has a huge energy conservation space, and it should therefore be generalized soon.展开更多
By means of low-field nuclear magnetic resonance(LF-NMR),the transverse relaxation time(T_(2))signals of physically bound water in cement paste were monitored to indicate water content change and characterize the earl...By means of low-field nuclear magnetic resonance(LF-NMR),the transverse relaxation time(T_(2))signals of physically bound water in cement paste were monitored to indicate water content change and characterize the early-age hydration process.With the curves of the T_(2)signals and hydration time obtained,the hydration process could be divided into four typical periods using the null points of the second derivative curve,and the influences of water-cement ratio(w/c)and hydration heat regulating materials(HHRM)on hydration process were analyzed.The experimental results showed that the hydration rate of pure cement paste in accelerated period presented a positive correlation with w/c.Compared to pure cement paste,the addition of HHRM extended all four periods,and led to a much faster hydration rate in initial period as well as a slower rate in accelerated period.Finally,according to the LFNMR test results,the early-age hydration model of cementitious materials was proposed considering w/c and HHRM content.展开更多
Targeted regulation of heat transfer in carbon/carbon composite structure is built for cooling electronic device.A three-dimensional data-driven design model coupling genetic algorithm(GA) with self-adaption deep lear...Targeted regulation of heat transfer in carbon/carbon composite structure is built for cooling electronic device.A three-dimensional data-driven design model coupling genetic algorithm(GA) with self-adaption deep learning for targeted regulation of heat transfer in built structure is proposed.The self-adaption deep learning model predicts the temperature of built structure closer to optimal value in GA model.The distributions of pore and carbon fiber bundles in built structure are optimized by the proposed model.The surface temperature of electronic device in the optimized structures is 19.1%-27.5% lower than that in the initial configurations when the porosity of built structure varies from 3% to 11%.The surface temperature of electronic device increases with an increase in porosity.The built structure with carbon fiber bundles near the surface of electronic device and pore distribution in the middle of structure has a higher heat dissipation capacity compared with that in the initial configuration.Besides,the computation time of the proposed model is less than one tenth compared with that of the traditional genetic algorithm.展开更多
A remote monitoring system for a secondary heating pipe network is designed on the basis of the KingSCADA software.Remote data communication is implemented through the IP mapping technology.Remote data are sorted thro...A remote monitoring system for a secondary heating pipe network is designed on the basis of the KingSCADA software.Remote data communication is implemented through the IP mapping technology.Remote data are sorted through IOServer,and the remote monitoring of the pipe network unit port return is implemented accordingly.Using data such as water temperature and pressure of the water supply and return pipes,valve opening can be remotely adjusted to optimize the performances of the network to meet user needs in real time.The research results show that this remote monitoring system displays a reasonable degree of stability and efficiency in remote communication.展开更多
The paper systematically summarizes the experience of Director Song Fuyin in treating Hashimoto's thyroiditis which is a typical emotional disease that causes obvious changes in organ morphology and endocrine and ...The paper systematically summarizes the experience of Director Song Fuyin in treating Hashimoto's thyroiditis which is a typical emotional disease that causes obvious changes in organ morphology and endocrine and body fluid metabolism.It belongs to the category of psychosomatic diseases,and is the embodiment of a series of pathogenesis processes of qi disease,blood disease,essence disease and deformation in TCM theory.The whole course of the disease is dominated by the dialectical relationship of mutual influence,mutual control,mutual root and mutual use among the deity disease,qi disease,blood disease,essence and spiritual disease.Therefore,the treatment emphasizes the dialectical relationship based on qi,blood,essence and spirit.At the beginning,the treatment focuses on regulating qi and clearing heat and eliminating phlegm;at the middle stage,the treatment focuses on replenishing essence and promoting yang and eliminating wind and calming the deity;at the late stage,the treatment focuses on replenishing qi and eliminating phlegm and promoting collages.Flexible use of calming the spirits,regulating qi,dispersing essence,eliminating phlegm,promoting blood and other methods of stage classification treatment,can be targeted,improve the cure rate of the disease.This article aims to clarify the experience of Director Song Fuyin in treating Hashimoto's thyroiditis based on syndrome differentiation of qi,blood essence and spirit.展开更多
This paper dealt with a series of numerical investigations on a new porous cooling channel applied to PV/T systems in order to improve the insufficient heat transfer in the conventional channel.The proposed porous coo...This paper dealt with a series of numerical investigations on a new porous cooling channel applied to PV/T systems in order to improve the insufficient heat transfer in the conventional channel.The proposed porous cooling channel based on field synergy theory had a higher overall heat transfer coefficient,which enhanced the total efficiency of the PV/T system.The numerical model was validated with experimental data.The results showed that holes distributed non-uniformly near the outlet of the cooling water led to a better cooling effect,and a hole diameter of 0.005 m led to an optimal performance.The total efficiency of the PV module with the new cooling channel was 4.17%higher than the conventional one at a solar irradiance of 1000 W/m^(2)and an inlet mass flow rate of 0.006 kg/s.In addition,as the solar irradiance increased from 300 to 1200 W/m^(2),the total efficiency of the new PV/T system dropped by 5.07%,which included reductions in both the electrical and thermal efficiency.The total efficiency was improved by 18.04%as the inlet mass flow rate of cooling water increased from 0.002 to 0.02 kg/s.展开更多
基金National Key R&D Program of China,Grant/Award Number:2022YFE0206500。
文摘The safety problems encountered with lithium–sulfur batteries(LSBs)hinder their development for practical applications.Herein,a highly thermally conductive separator was constructed by cross‐weaving super‐aligned carbon nanotubes(SA‐C)on super‐aligned boron nitride@carbon nanotubes(SA‐BC)to create a composite film(SA‐BC/SA‐C).This separator was used to fabricate safe LSBs with improved electrochemical performance.The highly aligned separator structure created a uniform thermal field that could rapidly dissipate heat accumulated during continuous operation due to internal resistance,which prevented the development of extremely high temperatures.The array of boron nitride nanosheets endowed the composite separator with a large number of adsorption sites,while the highly graphitized carbon nanotube skeleton accelerated the catalytic conversion of high‐valence polysulfides into low‐valence polysulfides.The arrayed molecular brush design enabled the regulation of local current density and ion flux,and considerably alleviated the growth of lithium dendrites,thus promoting the smooth deposition of Li metal.Consequently,a battery constructed with the SA‐BC/SA‐C separator showed a good discharge capacity of 685.2 mAh g−1 over 300 cycles(a capacity decay of 0.026%per cycle)at 2 C and 60°C.This“three‐in‐one”multifunctional separator design strategy constitutes a new path forward for overcoming the safety problems of LSBs.
文摘Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30% in a primary network when under a partial load. Through deducing and optimizing an exponential function flow regulation rule, the formulae of flow regulation and the supply and return water temperatures are obtained, and their relevant curves are plotted. After comparison, it is found that this control method has a huge energy conservation space, and it should therefore be generalized soon.
基金Funded by National Natural Science Foundation of China(Nos.U1965105,51878245)National Key R&D Program of China(No.2021YFF0500802)。
文摘By means of low-field nuclear magnetic resonance(LF-NMR),the transverse relaxation time(T_(2))signals of physically bound water in cement paste were monitored to indicate water content change and characterize the early-age hydration process.With the curves of the T_(2)signals and hydration time obtained,the hydration process could be divided into four typical periods using the null points of the second derivative curve,and the influences of water-cement ratio(w/c)and hydration heat regulating materials(HHRM)on hydration process were analyzed.The experimental results showed that the hydration rate of pure cement paste in accelerated period presented a positive correlation with w/c.Compared to pure cement paste,the addition of HHRM extended all four periods,and led to a much faster hydration rate in initial period as well as a slower rate in accelerated period.Finally,according to the LFNMR test results,the early-age hydration model of cementitious materials was proposed considering w/c and HHRM content.
基金supported by Guangdong Basic and Applied Basic Research Foundation (2023A1515012297)。
文摘Targeted regulation of heat transfer in carbon/carbon composite structure is built for cooling electronic device.A three-dimensional data-driven design model coupling genetic algorithm(GA) with self-adaption deep learning for targeted regulation of heat transfer in built structure is proposed.The self-adaption deep learning model predicts the temperature of built structure closer to optimal value in GA model.The distributions of pore and carbon fiber bundles in built structure are optimized by the proposed model.The surface temperature of electronic device in the optimized structures is 19.1%-27.5% lower than that in the initial configurations when the porosity of built structure varies from 3% to 11%.The surface temperature of electronic device increases with an increase in porosity.The built structure with carbon fiber bundles near the surface of electronic device and pore distribution in the middle of structure has a higher heat dissipation capacity compared with that in the initial configuration.Besides,the computation time of the proposed model is less than one tenth compared with that of the traditional genetic algorithm.
基金This work was supported by the Hebei Province Innovation Capability Enhancement Project(19244503D)the Hebei Province Key R&D Program Project(20374504D)the Hebei Province Higher Education Science and Technology Research and Development Project(ZD2020332).
文摘A remote monitoring system for a secondary heating pipe network is designed on the basis of the KingSCADA software.Remote data communication is implemented through the IP mapping technology.Remote data are sorted through IOServer,and the remote monitoring of the pipe network unit port return is implemented accordingly.Using data such as water temperature and pressure of the water supply and return pipes,valve opening can be remotely adjusted to optimize the performances of the network to meet user needs in real time.The research results show that this remote monitoring system displays a reasonable degree of stability and efficiency in remote communication.
文摘The paper systematically summarizes the experience of Director Song Fuyin in treating Hashimoto's thyroiditis which is a typical emotional disease that causes obvious changes in organ morphology and endocrine and body fluid metabolism.It belongs to the category of psychosomatic diseases,and is the embodiment of a series of pathogenesis processes of qi disease,blood disease,essence disease and deformation in TCM theory.The whole course of the disease is dominated by the dialectical relationship of mutual influence,mutual control,mutual root and mutual use among the deity disease,qi disease,blood disease,essence and spiritual disease.Therefore,the treatment emphasizes the dialectical relationship based on qi,blood,essence and spirit.At the beginning,the treatment focuses on regulating qi and clearing heat and eliminating phlegm;at the middle stage,the treatment focuses on replenishing essence and promoting yang and eliminating wind and calming the deity;at the late stage,the treatment focuses on replenishing qi and eliminating phlegm and promoting collages.Flexible use of calming the spirits,regulating qi,dispersing essence,eliminating phlegm,promoting blood and other methods of stage classification treatment,can be targeted,improve the cure rate of the disease.This article aims to clarify the experience of Director Song Fuyin in treating Hashimoto's thyroiditis based on syndrome differentiation of qi,blood essence and spirit.
基金The authors gratefully acknowledge the funding support from the Natural Science Foundation of Heilongjiang Province(Project#:YQ2020E019)。
文摘This paper dealt with a series of numerical investigations on a new porous cooling channel applied to PV/T systems in order to improve the insufficient heat transfer in the conventional channel.The proposed porous cooling channel based on field synergy theory had a higher overall heat transfer coefficient,which enhanced the total efficiency of the PV/T system.The numerical model was validated with experimental data.The results showed that holes distributed non-uniformly near the outlet of the cooling water led to a better cooling effect,and a hole diameter of 0.005 m led to an optimal performance.The total efficiency of the PV module with the new cooling channel was 4.17%higher than the conventional one at a solar irradiance of 1000 W/m^(2)and an inlet mass flow rate of 0.006 kg/s.In addition,as the solar irradiance increased from 300 to 1200 W/m^(2),the total efficiency of the new PV/T system dropped by 5.07%,which included reductions in both the electrical and thermal efficiency.The total efficiency was improved by 18.04%as the inlet mass flow rate of cooling water increased from 0.002 to 0.02 kg/s.
