We put forward a protocolcombining laser treatment and acid etching to obtain multiscale micro/nano-texture surfaces of titanium alloy implant.Firstly,the operationalparameters of the laser were optimized to obtain an...We put forward a protocolcombining laser treatment and acid etching to obtain multiscale micro/nano-texture surfaces of titanium alloy implant.Firstly,the operationalparameters of the laser were optimized to obtain an optimum current.Secondly,the laser with the optimum operationalparameters was used to fabricate micro pits.Thirdly,multiple acid etching was used to clean the clinkers of micro pits and generate submicron and nanoscale structures.Finally,the bioactivity of the samples was measured in a simulated body fluid.The results showed that the micropits with a diameter of 150 μm and depth of 50 μm were built successfully with the optimized working current of 13 A.In addition,submicron and nanoscale structures,with 0.5-2 μm microgrooves and 10-20 nm nanopits,were superimposed on micro pits surface by multiple acid etching.There was thick and dense HA coating only observed on the multiscale micro/nano-textured surface compared with polished and micro-textured surface.This indicated that the multiscale micro/nano-texture surface showed better ability toward HA formation,which increased the bioactivity of implants.展开更多
A novel way of producing superhydrophobic surfaces by applying a self-assembled monolayer(SAM)to silicon micro/nano-textured surfaces is presented in this paper.The micro/nano-textured surfaces on silicon substrates w...A novel way of producing superhydrophobic surfaces by applying a self-assembled monolayer(SAM)to silicon micro/nano-textured surfaces is presented in this paper.The micro/nano-textured surfaces on silicon substrates were generated by the aluminum-induced crystallization(AIC)of amorphous silicon(a-Si)technique.Octadecyltrichlorosilane(OTS)SAMs were then applied to the textured surfaces by dip coating.The topography and wetting properties of the resulting surfaces were characterized using scanning electron microscopy(SEM)and a video-based contact angle measurement system.The results show that by introducing OTS SAMs on the silicon micro/nano-textured surfaces,superhydrophobic surfaces with water contact angles(WCAs)of 155°were obtained,as compared to the WCAs of OTS-modified smooth silicon surfaces of about 112°.Surface topography was found to directly influence the WCA as predicted by the Cassie-Baxter model.展开更多
By observing four samples obtained from Jiangxi Province, China, under the scanning electron mi-croscope (SEM), we discovered that nano-particle layers were commonly formed on sliding planes of the penetrative foliati...By observing four samples obtained from Jiangxi Province, China, under the scanning electron mi-croscope (SEM), we discovered that nano-particle layers were commonly formed on sliding planes of the penetrative foliation in metamorphic rocks. We also successfully reproduced this phenomenon with a tri-axial pressure experiment. Having gone through the granulitization-alienation-partition in the shear sliding process, the nano-particles (40-95 nm in diameter) display different individual shapes and dis-tinct layered textures. This nano-confinement layer is essentially a frictional-viscous stripe with vis-cous-elastic deformation. In the micro-domain stripe, activities in structural stress field-rheological physical field-geochemical field are very dynamic, corresponding to the three stages (i.e., shear sliding strengthening-weakening-exfoliating) of the foliation development in metamorphism rocks. As such, the viscous-elastic deformation behavior helps shed light on the understanding of the micro-dynamic mechanism of the structural shearing.展开更多
Three types of textured indium-tin-oxide (ITO) surface, including nano-texturing and hybrid micro/nano-texturing with micro-holes (concave-hybrid-pattem) or micro-pillars (convex-hybrid-pattern), were applied to...Three types of textured indium-tin-oxide (ITO) surface, including nano-texturing and hybrid micro/nano-texturing with micro-holes (concave-hybrid-pattem) or micro-pillars (convex-hybrid-pattern), were applied to GaN-based light-emitting diodes (LEDs). The nano-texturing was realized by maskless wet-etching, and the micro-texturing was achieved by standard photolithography and wet-etching. Compared to LED chips with flat ITO surface, those with nano-pattern, concave-hybrid-pattern, and convex-hybrid-pattern exhibit enhancement of 11.3%, 15.8%, and 17.9%, respectively, for the light-output powers at 20 mA. The electrical performance has no degradation. Moreover, the convex-hybrid-pattern show higher light-output efficiency under small injection current, while the concave-hybrid-pattern exhibit better light-output efficiency at large injection current. The light- extraction efficiency is simulated by use of two-dimensional finite difference time domain method, and the numer- ical results are consistent with the experiments.展开更多
The objective of this study was to investigate the effect of a new combined micro/nanoscale implant surface feature on osteoblasts' behaviors including cell morphology, adhesion, proliferation, differentiation, and m...The objective of this study was to investigate the effect of a new combined micro/nanoscale implant surface feature on osteoblasts' behaviors including cell morphology, adhesion, proliferation, differentiation, and mineralization in vitro. A new micro/nano-hybrid topography surface was fabricated on commercial pure titanium(Cp Ti) by a two-step sandblasted acid-etching and subsequent alkali-and heattreatment(SA-AH). The conventional sandblasted/acid-etching(SA) treatment and alkali and heat(AH) treatment were also carried out on the Cp Ti as controls. Surface microstructures of the Ti disc samples were assessed by scanning electron microscopy(SEM). The neonatal rat calvaria-derived osteoblasts were seeded on these discs and the initial cell morphology was evaluated by SEM and immunofluorescence. Initial adhesion of the cells was then assayed by DAPI staining at 1, 2, and 4 h after seeding. The Cell Counting Kit-8(CCact K8) assay, gene expression of osteoblastic markers(ALP, Col 1, OCN, BSP, OSX, Cbfα1) and Alizarin Red S staining assays were monitored respectively for cell proliferations, differentiation and mineralization. The results show significant differences in osteoblast's behaviors on the four kinds of Ti surfaces. Compared with Cp Ti surface, the SA and AH treatment can significantly promote cell adhesion, differentiation and mineralization of osteoblasts. In particular, the combined SA and AH treatments exhibit synergistic effects in comparison with the treatment of SA and AH individually, and are more favorable for stimulating a series of osteogenous responses from cell adhesion to mineralization of osteoblasts. In summary, this study provides some new evidence that the integrated micro/nanostructure on the Cp Ti surface may promote bone osseointegration between the Ti implantbone interfaces in vitro.展开更多
基金Funded by the National Natural Science Foundation of China(51175306 and 51575320)the Tai Shan Scholar Foundation(TS20130922)the Fundamental Research Funds for the Central Universities(2014JC020)
文摘We put forward a protocolcombining laser treatment and acid etching to obtain multiscale micro/nano-texture surfaces of titanium alloy implant.Firstly,the operationalparameters of the laser were optimized to obtain an optimum current.Secondly,the laser with the optimum operationalparameters was used to fabricate micro pits.Thirdly,multiple acid etching was used to clean the clinkers of micro pits and generate submicron and nanoscale structures.Finally,the bioactivity of the samples was measured in a simulated body fluid.The results showed that the micropits with a diameter of 150 μm and depth of 50 μm were built successfully with the optimized working current of 13 A.In addition,submicron and nanoscale structures,with 0.5-2 μm microgrooves and 10-20 nm nanopits,were superimposed on micro pits surface by multiple acid etching.There was thick and dense HA coating only observed on the multiscale micro/nano-textured surface compared with polished and micro-textured surface.This indicated that the multiscale micro/nano-texture surface showed better ability toward HA formation,which increased the bioactivity of implants.
基金This material is based on work supported by the US National Science Foundation under Grant Nos.CMMI-0600642 and CMMI-0645040.
文摘A novel way of producing superhydrophobic surfaces by applying a self-assembled monolayer(SAM)to silicon micro/nano-textured surfaces is presented in this paper.The micro/nano-textured surfaces on silicon substrates were generated by the aluminum-induced crystallization(AIC)of amorphous silicon(a-Si)technique.Octadecyltrichlorosilane(OTS)SAMs were then applied to the textured surfaces by dip coating.The topography and wetting properties of the resulting surfaces were characterized using scanning electron microscopy(SEM)and a video-based contact angle measurement system.The results show that by introducing OTS SAMs on the silicon micro/nano-textured surfaces,superhydrophobic surfaces with water contact angles(WCAs)of 155°were obtained,as compared to the WCAs of OTS-modified smooth silicon surfaces of about 112°.Surface topography was found to directly influence the WCA as predicted by the Cassie-Baxter model.
基金the National Natural Science Foundation of China (Grant Nos. 40634022, 40673041, 40572118, and 40372092)the State Key Laboratory of Geology and Exploitation of Petroleum Reservoir
文摘By observing four samples obtained from Jiangxi Province, China, under the scanning electron mi-croscope (SEM), we discovered that nano-particle layers were commonly formed on sliding planes of the penetrative foliation in metamorphic rocks. We also successfully reproduced this phenomenon with a tri-axial pressure experiment. Having gone through the granulitization-alienation-partition in the shear sliding process, the nano-particles (40-95 nm in diameter) display different individual shapes and dis-tinct layered textures. This nano-confinement layer is essentially a frictional-viscous stripe with vis-cous-elastic deformation. In the micro-domain stripe, activities in structural stress field-rheological physical field-geochemical field are very dynamic, corresponding to the three stages (i.e., shear sliding strengthening-weakening-exfoliating) of the foliation development in metamorphism rocks. As such, the viscous-elastic deformation behavior helps shed light on the understanding of the micro-dynamic mechanism of the structural shearing.
基金Project supported by the National High Technology Research and Development Program of China(No.2014AA032609)the Strategic Emerging Industry Special Funds of Guangdong Province(Nos.2010A081002009,2011A081301004,2012A080302003)the Fundamental Research Funds for the Central Universities(Nos.2013ZM093,2013ZP0017)
文摘Three types of textured indium-tin-oxide (ITO) surface, including nano-texturing and hybrid micro/nano-texturing with micro-holes (concave-hybrid-pattem) or micro-pillars (convex-hybrid-pattern), were applied to GaN-based light-emitting diodes (LEDs). The nano-texturing was realized by maskless wet-etching, and the micro-texturing was achieved by standard photolithography and wet-etching. Compared to LED chips with flat ITO surface, those with nano-pattern, concave-hybrid-pattern, and convex-hybrid-pattern exhibit enhancement of 11.3%, 15.8%, and 17.9%, respectively, for the light-output powers at 20 mA. The electrical performance has no degradation. Moreover, the convex-hybrid-pattern show higher light-output efficiency under small injection current, while the concave-hybrid-pattern exhibit better light-output efficiency at large injection current. The light- extraction efficiency is simulated by use of two-dimensional finite difference time domain method, and the numer- ical results are consistent with the experiments.
基金Funded by the Natural Science Fundation of Zhejiang Province(Nos.Y2080956 and Y4110169)the National Natural Science Foundation of China(Nos.51102211,and 20934003)the Science and Technique Plans of Wenzhou City(Nos.Y20070093 and H20100076)
文摘The objective of this study was to investigate the effect of a new combined micro/nanoscale implant surface feature on osteoblasts' behaviors including cell morphology, adhesion, proliferation, differentiation, and mineralization in vitro. A new micro/nano-hybrid topography surface was fabricated on commercial pure titanium(Cp Ti) by a two-step sandblasted acid-etching and subsequent alkali-and heattreatment(SA-AH). The conventional sandblasted/acid-etching(SA) treatment and alkali and heat(AH) treatment were also carried out on the Cp Ti as controls. Surface microstructures of the Ti disc samples were assessed by scanning electron microscopy(SEM). The neonatal rat calvaria-derived osteoblasts were seeded on these discs and the initial cell morphology was evaluated by SEM and immunofluorescence. Initial adhesion of the cells was then assayed by DAPI staining at 1, 2, and 4 h after seeding. The Cell Counting Kit-8(CCact K8) assay, gene expression of osteoblastic markers(ALP, Col 1, OCN, BSP, OSX, Cbfα1) and Alizarin Red S staining assays were monitored respectively for cell proliferations, differentiation and mineralization. The results show significant differences in osteoblast's behaviors on the four kinds of Ti surfaces. Compared with Cp Ti surface, the SA and AH treatment can significantly promote cell adhesion, differentiation and mineralization of osteoblasts. In particular, the combined SA and AH treatments exhibit synergistic effects in comparison with the treatment of SA and AH individually, and are more favorable for stimulating a series of osteogenous responses from cell adhesion to mineralization of osteoblasts. In summary, this study provides some new evidence that the integrated micro/nanostructure on the Cp Ti surface may promote bone osseointegration between the Ti implantbone interfaces in vitro.