One process based on phase inversion of fillers in microstructures for the fabrication of multi-level three-dimensional(3-D) microstructures is described using SU-8, a kind of epoxy photoresist, as the model construct...One process based on phase inversion of fillers in microstructures for the fabrication of multi-level three-dimensional(3-D) microstructures is described using SU-8, a kind of epoxy photoresist, as the model constructing materials. This process is depicted by use of the routine photolithography technique to construct the top layer of 3-D microstructures on the bottom layer of 3-D microstructures layer by layer. This process makes it possible to fabricate multi-level 3-D microstructures with connectors at desired locations, and to seal long span microstructures(e.g. very shallow channels with depth less than 50 μm and width more than 300 μm) without blockage. In addition, this process can provide a sealing layer by the solidification of a liquid polymer layer, which can be as strong as the bulk constructing materials for microstructures due to a complete contact and cross-linking between the sealing layer and the patterned layers. The hydrodynamic testing indicates that this kind of sealing and interconnection can endure a static pressure of more than 10 MPa overnight and a hydrodynamic pressure drop of about 5.3 MPa for more than 8 hours by pumping the tetrahydrofuran solution through a 60 μm wide micro-channels.展开更多
The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics community.It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of...The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics community.It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or higher.The STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard Model.The STCF project in China is under development with an extensive R&D program.This document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.展开更多
Additive manufacturing based on liquid resin curing is one of the most promising methods to construct delicate structures.However,precision and speed are limited by the vertical adhesion of in situ cured resin at the ...Additive manufacturing based on liquid resin curing is one of the most promising methods to construct delicate structures.However,precision and speed are limited by the vertical adhesion of in situ cured resin at the curing interface.To overcome the unavoidable adhesion and to develop a general curing interface,we propose a slippery surface taking inspiration of the peristome surface of the pitcher plant.Such surface shows ultra-low adhesive energy at the curing interface due to the inhibition of the direct contact between the cured resin and the solid surface,which also increases the reflling speed of liquid resin.Tis ultra-low adhesive energy interface is efective for continuous 3D printing and provides insights into the physical mechanisms in reducing vertical solid-solid interfacial adhesion.展开更多
基金financially supported by the National Science Foundation of China(No.50971010)New Teacher Foundation of Beihang University(211109)+1 种基金New Teacher Funds of Education Ministry of China(2008-00061025)SRF and SEM funds of Education Ministry of China
文摘One process based on phase inversion of fillers in microstructures for the fabrication of multi-level three-dimensional(3-D) microstructures is described using SU-8, a kind of epoxy photoresist, as the model constructing materials. This process is depicted by use of the routine photolithography technique to construct the top layer of 3-D microstructures on the bottom layer of 3-D microstructures layer by layer. This process makes it possible to fabricate multi-level 3-D microstructures with connectors at desired locations, and to seal long span microstructures(e.g. very shallow channels with depth less than 50 μm and width more than 300 μm) without blockage. In addition, this process can provide a sealing layer by the solidification of a liquid polymer layer, which can be as strong as the bulk constructing materials for microstructures due to a complete contact and cross-linking between the sealing layer and the patterned layers. The hydrodynamic testing indicates that this kind of sealing and interconnection can endure a static pressure of more than 10 MPa overnight and a hydrodynamic pressure drop of about 5.3 MPa for more than 8 hours by pumping the tetrahydrofuran solution through a 60 μm wide micro-channels.
基金supported by the National Key R&D Program of China under Contract No.2022YFA1602200the International Partnership Program of the Chineses Academy of Sciences under Grant No.211134KYSB20200057the STCF Key Technology Research and Development Project.
文摘The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics community.It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or higher.The STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard Model.The STCF project in China is under development with an extensive R&D program.This document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.
基金Te authors L.Wu,Z.Dong,C.Li,and Y.Song acknowledge the National Key R&D Program of China(Grant Nos.2018YFA0208501,2016YFB0401603,2016YFC1100502,and 2016YFB0401100)the NSFC(Grant Nos.51803219,51773206,51473172,51473173,and 21671193)+1 种基金and the“Strategic Priority Research Program”of the Chinese Academy of Sciences(Grant No.XDA09020000)N.X.Fang and H.Du are grateful for the seed provided by the MIT Energy Initiative.
文摘Additive manufacturing based on liquid resin curing is one of the most promising methods to construct delicate structures.However,precision and speed are limited by the vertical adhesion of in situ cured resin at the curing interface.To overcome the unavoidable adhesion and to develop a general curing interface,we propose a slippery surface taking inspiration of the peristome surface of the pitcher plant.Such surface shows ultra-low adhesive energy at the curing interface due to the inhibition of the direct contact between the cured resin and the solid surface,which also increases the reflling speed of liquid resin.Tis ultra-low adhesive energy interface is efective for continuous 3D printing and provides insights into the physical mechanisms in reducing vertical solid-solid interfacial adhesion.