Self-healing materials have been developed over the past decade with the recovery ability after damage.However,most researches focused on the self-healing process at three-dimension.Herein,we prepare monolayer self-he...Self-healing materials have been developed over the past decade with the recovery ability after damage.However,most researches focused on the self-healing process at three-dimension.Herein,we prepare monolayer self-healing hydrogen-bond-based supramolecular polymer film and explore the self-healing process at the two-dimensional limit.The healing process,which can be reversibly repeated for at least three times,is influenced by the temperature,the molecule-substrate interaction and the substrate roughness.In the application,the monolayer self-healing polymer film can be used to modify the SiO2 dielectric for copper phthalocyanine field effect transistor with improved mobility.This work will be valuable for developing two-dimensional functional self-healing materials in the future.展开更多
In order to maintain higher emergence rate with direct seeding in Shandong rocky mountain, effects of different covering ways on emergence rate of Sophora japonica L. direct seeding were studied. The results showed th...In order to maintain higher emergence rate with direct seeding in Shandong rocky mountain, effects of different covering ways on emergence rate of Sophora japonica L. direct seeding were studied. The results showed that both mulching film and grass cover could effectively increase the moisture content of the soil at the depth of 0-30 cm, contributing to soil moisture conservation and the inhibition of soil evaporation, which created favorable moisture environment for the growth of S. japonica seeds. Both the emergence rate and the seedling height under mulching film had greater improvement and partly enhanced by 26.65% and 6.85 cm respectively, and mulching film also helped S. japonica seeds emerge and ensured the seedling growth. The emergence rate and the seedling height under grass cover had been also raised in some degree, but they were much worse than those under mulching film. The emergence rate and the seedling height under block cover were not significantly increased. So when sowing S. japonica seeds in the spring, mulching film is the best covering way.展开更多
Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional path...Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic devices.Indeed,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of NFRHT.In this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling ratio.The results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is 0.5.Moreover,the spectral heat flux exhibits redshift with increase in the vacuum filling ratio.To be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon polaritons.The introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon polaritons.These findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.展开更多
基金supported by National Program for Thousand Young Talents of China,the National Natural Science Foundation of China(Nos.51773041,21544001,21603038)Shanghai Committee of Science and Technology in China(No.18ZR1404900)Fudan University
文摘Self-healing materials have been developed over the past decade with the recovery ability after damage.However,most researches focused on the self-healing process at three-dimension.Herein,we prepare monolayer self-healing hydrogen-bond-based supramolecular polymer film and explore the self-healing process at the two-dimensional limit.The healing process,which can be reversibly repeated for at least three times,is influenced by the temperature,the molecule-substrate interaction and the substrate roughness.In the application,the monolayer self-healing polymer film can be used to modify the SiO2 dielectric for copper phthalocyanine field effect transistor with improved mobility.This work will be valuable for developing two-dimensional functional self-healing materials in the future.
基金subsidized by the project of "Direct seeding afforestation technology and demonstration in barren hills suitable forafforestation" supported by Shandong Forestry Bureau
文摘In order to maintain higher emergence rate with direct seeding in Shandong rocky mountain, effects of different covering ways on emergence rate of Sophora japonica L. direct seeding were studied. The results showed that both mulching film and grass cover could effectively increase the moisture content of the soil at the depth of 0-30 cm, contributing to soil moisture conservation and the inhibition of soil evaporation, which created favorable moisture environment for the growth of S. japonica seeds. Both the emergence rate and the seedling height under mulching film had greater improvement and partly enhanced by 26.65% and 6.85 cm respectively, and mulching film also helped S. japonica seeds emerge and ensured the seedling growth. The emergence rate and the seedling height under grass cover had been also raised in some degree, but they were much worse than those under mulching film. The emergence rate and the seedling height under block cover were not significantly increased. So when sowing S. japonica seeds in the spring, mulching film is the best covering way.
基金Project supported by the National Natural Science Foundation of China (Grant No.52106099)the Natural Science Foundation of Shandong Province (Grant No.ZR2022YQ57)the Taishan Scholars Program。
文摘Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic devices.Indeed,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of NFRHT.In this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling ratio.The results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is 0.5.Moreover,the spectral heat flux exhibits redshift with increase in the vacuum filling ratio.To be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon polaritons.The introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon polaritons.These findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.
