Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposit...Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposited onto microcrystalline titanium substrate by plasma alloying. As a result, modified surface layer composed of Ti matrix and TiB borides was obtained. The type of the powder precursor influenced recasting process, possible occurrence of porosity and finally the obtained properties and microstructure of the surface layer. Different morphologies and sizes of TiB phase from micro, submicro to even nano increased the hardness and wear resistance of the obtained surface layers. Discussed results referred to a strong TiB precipitation dispersion provided by a fine elements homogenization during mechanical alloying process. Additionally, results of in vitro test with normal human osteoblast cells revealed proper cellular adhesion to modified surfaces. Scanning electron microscopy observation revealed the influence of gas pore size on culturing osteoblast colony. The proposed surface alloying was an effective method of producing TiB phase dispersed in α-Ti matrix with high hardness, good corrosion resistance and good cytocompatibility. Results confirmed that different types of the precursor powders influenced the properties of the surface layer. TiB phase dispersed in α-Ti matrix layer can offer new structural and biofunctional properties for innovative products in hard tissue applications.展开更多
A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, ...A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, hardness and corrosion resistance in Ringer solution of the Ag-doped Ti-45S5 glass were investigated. The Vickers hardness of the bulk Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag nanocomposites reached 480 HVo.3. Contact angles of water on the micro- crystalline Ti and nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag sample were determined and show visible decrease from 55.2° to 49.6°. In vitro tests culture of normal human osteoblast cells showed very good cells proliferation, colonization and multilayering. In vitro bacterial adhesion study indicated a significantly reduced number of bacteria （Staphylococcus aureus） on the bulk nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag plate surface in comparison with that on microcrystalline Ti plate surface. Development of porous Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag scaffolds aims in enhancing bone ingrowth and prosthesis fixation.展开更多
Joint experiments(JEs)on small tokamaks have been regularly performed between 2005 and 2015 under the framework of the International Atomic Energy Agency(IAEA)coordinated research projects(CRPs).This paper describes t...Joint experiments(JEs)on small tokamaks have been regularly performed between 2005 and 2015 under the framework of the International Atomic Energy Agency(IAEA)coordinated research projects(CRPs).This paper describes the background and the rationale for these experiments,how they were organized and executed,main areas of research covered during these experiments,main results,contributions to mainstream fusion research,and discusses lessons learned and outcomes from these activities.We underline several of the most important scientific outputs and also specific outputs in the education of young scientists and scientists from developing countries and their importance.展开更多
文摘Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposited onto microcrystalline titanium substrate by plasma alloying. As a result, modified surface layer composed of Ti matrix and TiB borides was obtained. The type of the powder precursor influenced recasting process, possible occurrence of porosity and finally the obtained properties and microstructure of the surface layer. Different morphologies and sizes of TiB phase from micro, submicro to even nano increased the hardness and wear resistance of the obtained surface layers. Discussed results referred to a strong TiB precipitation dispersion provided by a fine elements homogenization during mechanical alloying process. Additionally, results of in vitro test with normal human osteoblast cells revealed proper cellular adhesion to modified surfaces. Scanning electron microscopy observation revealed the influence of gas pore size on culturing osteoblast colony. The proposed surface alloying was an effective method of producing TiB phase dispersed in α-Ti matrix with high hardness, good corrosion resistance and good cytocompatibility. Results confirmed that different types of the precursor powders influenced the properties of the surface layer. TiB phase dispersed in α-Ti matrix layer can offer new structural and biofunctional properties for innovative products in hard tissue applications.
文摘A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, hardness and corrosion resistance in Ringer solution of the Ag-doped Ti-45S5 glass were investigated. The Vickers hardness of the bulk Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag nanocomposites reached 480 HVo.3. Contact angles of water on the micro- crystalline Ti and nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag sample were determined and show visible decrease from 55.2° to 49.6°. In vitro tests culture of normal human osteoblast cells showed very good cells proliferation, colonization and multilayering. In vitro bacterial adhesion study indicated a significantly reduced number of bacteria （Staphylococcus aureus） on the bulk nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag plate surface in comparison with that on microcrystalline Ti plate surface. Development of porous Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag scaffolds aims in enhancing bone ingrowth and prosthesis fixation.
基金supported by funding by the IAEA technical contracts within IAEA Coordinated Research Projects on‘Joint Research Using Small Tokamaks’and on‘Utilisation of a Network of Small Magnetic Confinement Fusion Devices for Mainstream Fusion Research’funded by Russian Science Foundation,Project 19-12-00312+3 种基金partly supported by the Competitiveness Program of NRNU MEPhIthe partial financial support from MEPhI and NRU MPEI in the framework of the Russian Academic Excellence Projectsupported by Tokamak Energy LtdOxford Instruments(UK)。
文摘Joint experiments(JEs)on small tokamaks have been regularly performed between 2005 and 2015 under the framework of the International Atomic Energy Agency(IAEA)coordinated research projects(CRPs).This paper describes the background and the rationale for these experiments,how they were organized and executed,main areas of research covered during these experiments,main results,contributions to mainstream fusion research,and discusses lessons learned and outcomes from these activities.We underline several of the most important scientific outputs and also specific outputs in the education of young scientists and scientists from developing countries and their importance.
