To promote/inhibit ice formation in the natural environment and industrial systems,the growth and evolution process of ice single-crystal nuclei were simulated using the phase field-lattice Boltzmann method(PF-LBM),an...To promote/inhibit ice formation in the natural environment and industrial systems,the growth and evolution process of ice single-crystal nuclei were simulated using the phase field-lattice Boltzmann method(PF-LBM),and the influence of a background flow field on the growth of single-crystal nucleus dendrites was also analyzed.The results show that the flow field makes dendrite growth asymmetric.The growth of dendrites is more developed on the upstream side than on the downstream side.The dendrite tip growth rate and tip radius are greater on the upstream side than on the downstream side.The solid phase ratio is greater with a background flow field than without one.The higher the flow velocity is,the more developed the dendrites on the upstream side,the faster the dendrites grow,and the higher the dendrite tip growth rate.The dendrites on the backflow side have a lower flow rate and a lower degree of supercooling than those on the upstream side,which inhibits the solidification process,the growth rate is slow,and the dendrites are underdeveloped.展开更多
The highly sensitive and power efficient tactile sensors can provide grippers with vertical and shear forces from interactions with objects.In an ocean environment with low visual distance and high noise,sea otters ca...The highly sensitive and power efficient tactile sensors can provide grippers with vertical and shear forces from interactions with objects.In an ocean environment with low visual distance and high noise,sea otters can rely on their palms to accurately identify and grasp target objects without damage.Inspired by the structure of the sea otter’s palm,this paper proposes a distributed liquid metal-based three-dimensional biomimetic underwater triboelectric palm-like tactile sensor(UPTS)for feedback-controlled grippers.The device is mainly composed of a flexible shell,a flexible cover,a flexible support,a triboelectric sensing unit and a fixed shell.The force acting on the flexible cover causes the flexible cover and sensing unit to deform,so that the sensing unit undergoes a contact-separation process,thereby generating an electrical signal.UPTS has the capability to identify the magnitude and direction of force,with a direction recognition error angle within 5 degrees.Additionally,it can distinguish the hardness and shape of objects,achieving an accuracy rate of 100%and 99.75%respectively for the tested objects.The results indicate that UPTS can provide force feedback for underwater grippers,thereby assisting the grippers in better completing salvage task.展开更多
The charge interaction and corresponding doping effect between single-walled carbonnanotubes (SWNTs) and various fullerene derivatives, namely, C60, phenyl-C61-butyricacid methyl ester (PC61BM), methano-indenefulleren...The charge interaction and corresponding doping effect between single-walled carbonnanotubes (SWNTs) and various fullerene derivatives, namely, C60, phenyl-C61-butyricacid methyl ester (PC61BM), methano-indenefullerene (MIF), 10,100,40,400-tetrahydrodi[1,4]methanonaphthaleno[5,6]fullerene (ICBA), 1,4-bis(dimethylphenylsilylmethyl)[60]fullerene (SIMEF-1), and dimethyl(orthoanisyl) silylmethyl(dimethylphenylsilylmethyl)[60]fullerene (SIMEF-2), are investigated. A variety of analytical techniques,including field-effect transistors (FETs) made of horizontally aligned arrays ofSWNTs, is used as a means of investigation. Data from different measurements haveto be used to obtain a concrete evaluation for the fullerene-applied SWNTs. The datacollectively points toward the conclusion that fullerenes with high molecular orbitalenergy levels, namely, MIF, SIMEF-1, SIMEF-2, and PC61BM, induce p-type doping,while fullerenes with low molecular orbital energy levels, namely, ICBA and C60,induce n-type doping on the carbon nanotubes. Nevertheless, the SWNTs retained ptypecharacteristics because n-doping induced by the fullerenes are weak compared tothe p-doping of the water and oxygen on carbon nanotubes. This means that fullerenederivatives have the ability to fine-tune the energy levels of carbon nanotubes, whichcan play a crucial role in carbon nanotube-based electronics, such as solar cells, lightemittingdevices, and FETs.展开更多
基金The National Key Research and Development Program of China(No.2020YFB1506203)。
文摘To promote/inhibit ice formation in the natural environment and industrial systems,the growth and evolution process of ice single-crystal nuclei were simulated using the phase field-lattice Boltzmann method(PF-LBM),and the influence of a background flow field on the growth of single-crystal nucleus dendrites was also analyzed.The results show that the flow field makes dendrite growth asymmetric.The growth of dendrites is more developed on the upstream side than on the downstream side.The dendrite tip growth rate and tip radius are greater on the upstream side than on the downstream side.The solid phase ratio is greater with a background flow field than without one.The higher the flow velocity is,the more developed the dendrites on the upstream side,the faster the dendrites grow,and the higher the dendrite tip growth rate.The dendrites on the backflow side have a lower flow rate and a lower degree of supercooling than those on the upstream side,which inhibits the solidification process,the growth rate is slow,and the dendrites are underdeveloped.
基金supported by the Scientific Research Fund of the Educational Department of Liaoning Province(No.LJKZ0055)Dalian Outstanding Young Scientific and Technological Talents Project(No.2021RJ11)the Open Fund of National Center for International Research of Subsea Engineering Technology and Equipment(No.3132023354).
文摘The highly sensitive and power efficient tactile sensors can provide grippers with vertical and shear forces from interactions with objects.In an ocean environment with low visual distance and high noise,sea otters can rely on their palms to accurately identify and grasp target objects without damage.Inspired by the structure of the sea otter’s palm,this paper proposes a distributed liquid metal-based three-dimensional biomimetic underwater triboelectric palm-like tactile sensor(UPTS)for feedback-controlled grippers.The device is mainly composed of a flexible shell,a flexible cover,a flexible support,a triboelectric sensing unit and a fixed shell.The force acting on the flexible cover causes the flexible cover and sensing unit to deform,so that the sensing unit undergoes a contact-separation process,thereby generating an electrical signal.UPTS has the capability to identify the magnitude and direction of force,with a direction recognition error angle within 5 degrees.Additionally,it can distinguish the hardness and shape of objects,achieving an accuracy rate of 100%and 99.75%respectively for the tested objects.The results indicate that UPTS can provide force feedback for underwater grippers,thereby assisting the grippers in better completing salvage task.
基金Japan Science and Technology Agency,Grant/Award Number:CIAiSJapan Society for the Promotion of Science,Grant/Award Numbers:JP15H05760,JP16H02285,JP17K04970,JP 18H05329,JP19K15669Yashima Foundation。
文摘The charge interaction and corresponding doping effect between single-walled carbonnanotubes (SWNTs) and various fullerene derivatives, namely, C60, phenyl-C61-butyricacid methyl ester (PC61BM), methano-indenefullerene (MIF), 10,100,40,400-tetrahydrodi[1,4]methanonaphthaleno[5,6]fullerene (ICBA), 1,4-bis(dimethylphenylsilylmethyl)[60]fullerene (SIMEF-1), and dimethyl(orthoanisyl) silylmethyl(dimethylphenylsilylmethyl)[60]fullerene (SIMEF-2), are investigated. A variety of analytical techniques,including field-effect transistors (FETs) made of horizontally aligned arrays ofSWNTs, is used as a means of investigation. Data from different measurements haveto be used to obtain a concrete evaluation for the fullerene-applied SWNTs. The datacollectively points toward the conclusion that fullerenes with high molecular orbitalenergy levels, namely, MIF, SIMEF-1, SIMEF-2, and PC61BM, induce p-type doping,while fullerenes with low molecular orbital energy levels, namely, ICBA and C60,induce n-type doping on the carbon nanotubes. Nevertheless, the SWNTs retained ptypecharacteristics because n-doping induced by the fullerenes are weak compared tothe p-doping of the water and oxygen on carbon nanotubes. This means that fullerenederivatives have the ability to fine-tune the energy levels of carbon nanotubes, whichcan play a crucial role in carbon nanotube-based electronics, such as solar cells, lightemittingdevices, and FETs.
