Twenty-nine species of butterflies were collected for observation and determination of the wing surfaces using a Scanning Electron Microscope(SEM).Butterfly wing surface displays structural anisotropism in micro-,subm...Twenty-nine species of butterflies were collected for observation and determination of the wing surfaces using a Scanning Electron Microscope(SEM).Butterfly wing surface displays structural anisotropism in micro-,submicro- and nano-scales.The scales on butterfly wing surface arrange like overlapping roof tiles.There are submicrometric vertical gibbosities,horizontal links,and nano-protuberances on the scales.First-incline-then-drip method and first-drip-then-incline method were used to measure the Sliding Angle(SA)of droplet on butterfly wing surface by an optical Contact Angle(CA)measuring system. Relatively smaller sliding angles indicate that the butterfly wing surface has fine self-cleaning property.Significantly different SAs in various directions indicate the anisotropic self-cleaning property of butterfly wing surface.The SAs on the butterfly wing surface without scales are remarkably larger than those with scales,which proves the crucial role of scales in determining the self-cleaning property.Butterfly wing surface is a template for design and fabrication ofbiomimetic materials and self-cleaning substrates.This work may offer insights into how to design directional self-cleaning coatings and anisotropic wetting surface.展开更多
In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrol...In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrolytic Etching （EE）. MG-63 cells were cultured on disks for 2 h to 7 days. The osteoblast response to the hierarchical hybrid micro-/nano-structured titanium surface was evaluated through the osteoblast cell morphology, attachment and proliferation. For comparison, MG-63 cells were also cultured on Sandblasted and Acid-etched （SEA） as well as Machined （M） surfaces respectively. The results show signifi- cant differences in the adhesion rates and proliferation levels of MG-63 cells on EE, SLA, and M surfaces. Both adhesion rate and proliferation level on EE surface are higher than those on SLA and M surfaces. Therefore, we may expect that, comparing with SLA and M surfaces, bone growth on EE surface could be accelerated and bone formation could be promoted at an early stage, which could be applied in the clinical practices for immediate and early-stage loadings.展开更多
In this paper, the cement paste and the mortar were tested using the PF-QNM technique. It is shown that the PF-QNM technique is very powerful to characterize the mechanical properties of micro-and nanostructures in th...In this paper, the cement paste and the mortar were tested using the PF-QNM technique. It is shown that the PF-QNM technique is very powerful to characterize the mechanical properties of micro-and nanostructures in the cement-based materials. It does not have strict requirements for test environment and it does not damage the surface of the material. High-resolution images can be obtained very easily, and they can be analyzed statistically. The test results show that PF-QNM analysis can test not only the mechanical properties of the cement paste, but also investigate the interfacial regions in the cement-based material, including the variation in the mechanical properties of interface regions and the extension of the interfacial regions. During the test, care must be taken to choose the size of test area;indeed, a test area too small is not representative but too large leads to lack of stability. The recommended side is a square with a length of in the range 10-30 μm.展开更多
A multi-functional polymer film with high hydrophobicity and transparency was formed by simple casting of a polycarbonate solution onto a substrate having micro-scale roughness.The high hydrophobicity was heat-resista...A multi-functional polymer film with high hydrophobicity and transparency was formed by simple casting of a polycarbonate solution onto a substrate having micro-scale roughness.The high hydrophobicity was heat-resistant,which can be retained up to 390 ℃.The polymer film may have potentially wide-ranging applications in industry and high technology.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50635030)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20040183048)the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Twenty-nine species of butterflies were collected for observation and determination of the wing surfaces using a Scanning Electron Microscope(SEM).Butterfly wing surface displays structural anisotropism in micro-,submicro- and nano-scales.The scales on butterfly wing surface arrange like overlapping roof tiles.There are submicrometric vertical gibbosities,horizontal links,and nano-protuberances on the scales.First-incline-then-drip method and first-drip-then-incline method were used to measure the Sliding Angle(SA)of droplet on butterfly wing surface by an optical Contact Angle(CA)measuring system. Relatively smaller sliding angles indicate that the butterfly wing surface has fine self-cleaning property.Significantly different SAs in various directions indicate the anisotropic self-cleaning property of butterfly wing surface.The SAs on the butterfly wing surface without scales are remarkably larger than those with scales,which proves the crucial role of scales in determining the self-cleaning property.Butterfly wing surface is a template for design and fabrication ofbiomimetic materials and self-cleaning substrates.This work may offer insights into how to design directional self-cleaning coatings and anisotropic wetting surface.
文摘In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrolytic Etching （EE）. MG-63 cells were cultured on disks for 2 h to 7 days. The osteoblast response to the hierarchical hybrid micro-/nano-structured titanium surface was evaluated through the osteoblast cell morphology, attachment and proliferation. For comparison, MG-63 cells were also cultured on Sandblasted and Acid-etched （SEA） as well as Machined （M） surfaces respectively. The results show signifi- cant differences in the adhesion rates and proliferation levels of MG-63 cells on EE, SLA, and M surfaces. Both adhesion rate and proliferation level on EE surface are higher than those on SLA and M surfaces. Therefore, we may expect that, comparing with SLA and M surfaces, bone growth on EE surface could be accelerated and bone formation could be promoted at an early stage, which could be applied in the clinical practices for immediate and early-stage loadings.
基金Funded by the National Natural Science Foundation of China(51778582&51879235)the National Key R&D Plan(2017YFC0804809)
文摘In this paper, the cement paste and the mortar were tested using the PF-QNM technique. It is shown that the PF-QNM technique is very powerful to characterize the mechanical properties of micro-and nanostructures in the cement-based materials. It does not have strict requirements for test environment and it does not damage the surface of the material. High-resolution images can be obtained very easily, and they can be analyzed statistically. The test results show that PF-QNM analysis can test not only the mechanical properties of the cement paste, but also investigate the interfacial regions in the cement-based material, including the variation in the mechanical properties of interface regions and the extension of the interfacial regions. During the test, care must be taken to choose the size of test area;indeed, a test area too small is not representative but too large leads to lack of stability. The recommended side is a square with a length of in the range 10-30 μm.
基金the National Natural Science Foundation of China(grant no.21101010)the Innovation Foundation of BUAA for PhD Graduates(296181)for continuing financial support
文摘A multi-functional polymer film with high hydrophobicity and transparency was formed by simple casting of a polycarbonate solution onto a substrate having micro-scale roughness.The high hydrophobicity was heat-resistant,which can be retained up to 390 ℃.The polymer film may have potentially wide-ranging applications in industry and high technology.
