Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not...Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not been reported, however, to prepare La_2O_3 ultrafine particles with urea as the hydrolytic agent. This method is easy to operate, and the materials are cheap and easily available, besides, it is easy to obtain homogeneous spherical precursors of ultrafine particles. The present, paper describes the preparation of La_2O_3 ultrafine particles with urea as hydrolytic agent, and observes some of its characteristics.展开更多
A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during th...A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during the direct chilling casting process.The experimental results show that the new method can be used to prepare SiC particle-reinforced aluminum matrix composites;under the effects of the low frequency electromagnetic field,the microstructure of ingot is refined and the distribution of SiC particles is improved.展开更多
In conventional pulsed laser deposition （PLD） technique, plume deflection and composition distribution change with the laser incident direction and pulse energy, then causing uneven film thickness and composition di...In conventional pulsed laser deposition （PLD） technique, plume deflection and composition distribution change with the laser incident direction and pulse energy, then causing uneven film thickness and composition distribution for a multicomponent film and eventually leading to low device quality and low rate of final products. We present a novel method based on PLD for depositing large CIGS films with uni- form thickness and stoichiometry. By oscillating a mirror placed coaxially with the incident laser beam, the laser＇s focus is scanned across the rotating target surface. This arrangement maintains a constant re- flectance and optical distance, ensuring that a consistent energy density is delivered to the target surface by each laser pulse. Scanning the laser spot across the target suppresses the formation of micro-columns, and thus the plume deflection effect that reduces film uniformity in conventional PLD technique is eliminated. This coaxial scanning PLD method is used to deposit a CIGS film, 500 nm thick, with thickness uniformity exceeding ±3% within a 5 cm diameter, and exhibiting a highly homogeneous elemental distribution.展开更多
文摘Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not been reported, however, to prepare La_2O_3 ultrafine particles with urea as the hydrolytic agent. This method is easy to operate, and the materials are cheap and easily available, besides, it is easy to obtain homogeneous spherical precursors of ultrafine particles. The present, paper describes the preparation of La_2O_3 ultrafine particles with urea as hydrolytic agent, and observes some of its characteristics.
基金Funded by the National Natural Science Foundation of China(51574075)the National Basic Research Program of China(2012CB723307)+3 种基金the Hi-Tech Research and Development Program of China(2013AA032402)the Scientific Research Fund of Liaoning Provincial Education Department(L2013110)the Bureau of Shenyang city Science and Technology Project(F14-231-1-01)the Fundamental Research Funds for the Central Universities(120409005)
文摘A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during the direct chilling casting process.The experimental results show that the new method can be used to prepare SiC particle-reinforced aluminum matrix composites;under the effects of the low frequency electromagnetic field,the microstructure of ingot is refined and the distribution of SiC particles is improved.
基金supported by the Shenzhen Basic Research Project of Science and Technology under Grant No.JCYJ20120613112423982
文摘In conventional pulsed laser deposition （PLD） technique, plume deflection and composition distribution change with the laser incident direction and pulse energy, then causing uneven film thickness and composition distribution for a multicomponent film and eventually leading to low device quality and low rate of final products. We present a novel method based on PLD for depositing large CIGS films with uni- form thickness and stoichiometry. By oscillating a mirror placed coaxially with the incident laser beam, the laser＇s focus is scanned across the rotating target surface. This arrangement maintains a constant re- flectance and optical distance, ensuring that a consistent energy density is delivered to the target surface by each laser pulse. Scanning the laser spot across the target suppresses the formation of micro-columns, and thus the plume deflection effect that reduces film uniformity in conventional PLD technique is eliminated. This coaxial scanning PLD method is used to deposit a CIGS film, 500 nm thick, with thickness uniformity exceeding ±3% within a 5 cm diameter, and exhibiting a highly homogeneous elemental distribution.
