In recent years, high-altitude aerostats have been increasingly developed in the direction of multi-functionality and large size. Due to the large size and the high flexibility, new challenges for large aerostats have...In recent years, high-altitude aerostats have been increasingly developed in the direction of multi-functionality and large size. Due to the large size and the high flexibility, new challenges for large aerostats have appeared in the configuration test and the deformation analysis. The methods of the configuration test and the deformation analysis for large airship have been researched and discussed. A tested method of the configuration,named internal scanning, is established to quickly obtain the spatial information of all surfaces for the large airship by the three-dimensional(3D) laser scanning technology. By using the surface wrap method, the configuration parameters of the large airship are calculated. According to the test data of the configuration, the structural dimensions such as the distances between the characteristic sections are measured. The method of the deformation analysis for the airship contains the algorithm of nonuniform rational B-splines(NURBS) and the finite element(FE)method. The algorithm of NURBS is used to obtain the reconfiguration model of the large airship. The seams are considered and the seam areas are divided. The FE model of the middle part of the large airship is established. The distributions of the stress and the strain for the large airship are obtained by the FE method. The position of the larger deformation for the airship is found.展开更多
As photocrosslinkable materials,methacryloyl-modified hydrogels are widely used as bioinks in tissue engineering.Existing printing methods to use these hydrogels,including changing the viscosity of the material or mix...As photocrosslinkable materials,methacryloyl-modified hydrogels are widely used as bioinks in tissue engineering.Existing printing methods to use these hydrogels,including changing the viscosity of the material or mixing them with other printing components,have been explored,but their application has been limited due to low printing quality or high cost.In addition,the complex operation of bulky equipment restricts the application of these existing printing methods.This study presents a lightweight stereolithography-based three-dimensional(3D)bioprinting system with a smart mechanical and structural design.The developed bioprinter dimensions were 300 mm×300 mm×200 mm and it can be placed on a benchtop.The equipment has a mini bioink chamber to store a small amount of bioink for each printing.We systematically investigated the point-by-point curing process in the 3D bioprinting method,which can print mixed cells accurately and have good biocompatibility.Here,we provide a compact,low-cost stereolithography bioprinting system with excellent biocompatibility for 3D bioprinting with methacryloyl-modified hydrogels.It can be potentially used for drug screening,studying pathological mechanisms,and constructing biological disease models.展开更多
Electrospinning is a popular and effective method of producing porous nanofibers with a large surface area,superior physical and chemical properties,and a controllable pore size.Owing to these properties,electrospun n...Electrospinning is a popular and effective method of producing porous nanofibers with a large surface area,superior physical and chemical properties,and a controllable pore size.Owing to these properties,electrospun nanofibers can mimic the extracellular matrix and some human tissue structures,based on the fiber configuration.Consequently,the application of electrospun nanofibers as biomaterials,varying from two-dimensional(2D)wound dressings to three-dimensional(3D)tissue engineering scaffolds,has increased rapidly in recent years.Nanofibers can either be uniform fiber strands or coaxial drug carriers,and their overall structure varies from random mesh-like mats to aligned or gradient scaffolds.In addition,the pore size of the fibers can be adjusted or the fibers can be loaded with disparate medicines to provide different functions.This review discusses the various structures and applications of 2D fiber mats and 3D nanofibrous scaffolds made up of different one-dimensional(1D)fibers in tissue engineering.In particular,we focus on the improvements made in recent years,especially in the fields of wound healing,angiogenesis,and tissue regeneration.展开更多
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (11421091)。
文摘In recent years, high-altitude aerostats have been increasingly developed in the direction of multi-functionality and large size. Due to the large size and the high flexibility, new challenges for large aerostats have appeared in the configuration test and the deformation analysis. The methods of the configuration test and the deformation analysis for large airship have been researched and discussed. A tested method of the configuration,named internal scanning, is established to quickly obtain the spatial information of all surfaces for the large airship by the three-dimensional(3D) laser scanning technology. By using the surface wrap method, the configuration parameters of the large airship are calculated. According to the test data of the configuration, the structural dimensions such as the distances between the characteristic sections are measured. The method of the deformation analysis for the airship contains the algorithm of nonuniform rational B-splines(NURBS) and the finite element(FE)method. The algorithm of NURBS is used to obtain the reconfiguration model of the large airship. The seams are considered and the seam areas are divided. The FE model of the middle part of the large airship is established. The distributions of the stress and the strain for the large airship are obtained by the FE method. The position of the larger deformation for the airship is found.
基金support of National 863 Program(SS2012AA101306)“the 12th Five-Year Plan”,Jiangxi Advantageous Science and Technology Innovation Team Construction Plan(20153BCB24002)+2 种基金Collaborative Innovation Center Project of Intelligent Management Technology and Equipment for Southern Mountain Orchards(G.J.G.Z.[2014]No.60)National Natural Science Foundation of China(2002017018,51805474)the China Postdoctoral Science Foundation(Grant No.2019T120509).
文摘As photocrosslinkable materials,methacryloyl-modified hydrogels are widely used as bioinks in tissue engineering.Existing printing methods to use these hydrogels,including changing the viscosity of the material or mixing them with other printing components,have been explored,but their application has been limited due to low printing quality or high cost.In addition,the complex operation of bulky equipment restricts the application of these existing printing methods.This study presents a lightweight stereolithography-based three-dimensional(3D)bioprinting system with a smart mechanical and structural design.The developed bioprinter dimensions were 300 mm×300 mm×200 mm and it can be placed on a benchtop.The equipment has a mini bioink chamber to store a small amount of bioink for each printing.We systematically investigated the point-by-point curing process in the 3D bioprinting method,which can print mixed cells accurately and have good biocompatibility.Here,we provide a compact,low-cost stereolithography bioprinting system with excellent biocompatibility for 3D bioprinting with methacryloyl-modified hydrogels.It can be potentially used for drug screening,studying pathological mechanisms,and constructing biological disease models.
基金the funding from Medical Scientific Research Foundation of Guangdong Province(No.A2021093)Science and Technology Planning Project of Shenzhen Municipality(No.YJ20180306174831458)+7 种基金Shenzhen Basic Research Project(No.JCYJ20190807155801657)National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2018ZX10301402)Key International(Regional)Joint Research Program of China(No.5181001045)Guangdong Innovative and Entrepreneurial Research Team Program(No.2016ZT06S029)the National Natural Science Foundation of China(No.51973243)China Postdoctoral Science Foundation(No.2019M663246)the Fundamental Research Funds for the Central Universities(Nos.191gzd35 and 20ykpyl5)Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110686).
文摘Electrospinning is a popular and effective method of producing porous nanofibers with a large surface area,superior physical and chemical properties,and a controllable pore size.Owing to these properties,electrospun nanofibers can mimic the extracellular matrix and some human tissue structures,based on the fiber configuration.Consequently,the application of electrospun nanofibers as biomaterials,varying from two-dimensional(2D)wound dressings to three-dimensional(3D)tissue engineering scaffolds,has increased rapidly in recent years.Nanofibers can either be uniform fiber strands or coaxial drug carriers,and their overall structure varies from random mesh-like mats to aligned or gradient scaffolds.In addition,the pore size of the fibers can be adjusted or the fibers can be loaded with disparate medicines to provide different functions.This review discusses the various structures and applications of 2D fiber mats and 3D nanofibrous scaffolds made up of different one-dimensional(1D)fibers in tissue engineering.In particular,we focus on the improvements made in recent years,especially in the fields of wound healing,angiogenesis,and tissue regeneration.
