Bi0.5(Na0.85K0.15)0.5TiO3(BNKT15) thin films were synthesized by metal-organic decomposition(MOD) at annealing temperatures of 650,680,710 and 740℃,and the effects of annealing temperature on the microstructure,diele...Bi0.5(Na0.85K0.15)0.5TiO3(BNKT15) thin films were synthesized by metal-organic decomposition(MOD) at annealing temperatures of 650,680,710 and 740℃,and the effects of annealing temperature on the microstructure,dielectric properties,remnant polarization(2Pr) and leakage current density were studied with X-ray diffractometer,atomic force microscope,precision impedance analyzer,ferroelectric analysis station and semiconductor parameter tester.The results show that the thin film annealed at 710℃ exhibits a typical perovskite structure without predominant orientation and a smooth surface with evenly distributed grains.2Pr value(67.4 μC/cm2 under 830 kV/cm) and the leakage current density(1.6×10-6 A/cm2 at 170 kV/cm) for BNKT15 thin film annealed at 710℃ are better than those for thin films annealed at other temperatures.展开更多
Bi3.15Nd0.85Ti3O12(BNT) powder and thin film were prepared by metal organic decomposition(MOD) method.The heat flow curve of BNT powder was measured with a modulated temperature differential scanning calorimeter,and t...Bi3.15Nd0.85Ti3O12(BNT) powder and thin film were prepared by metal organic decomposition(MOD) method.The heat flow curve of BNT powder was measured with a modulated temperature differential scanning calorimeter,and thermal physical parameters such as thermal conductivity coefficient and thermal diffusion coefficient were obtained from the heat flow curve.The phase identification,ferroelectric,and piezoelectric properties of BNT thin film annealed at 700°C were investigated with X-ray diffractometer,ferroelectric analyzer,and scanning probe microscope.The results show that the thin films consisting of a single phase of bismuth-layered perovskite are polycrystalline,without a preferred orientation.Remnant polarization 2Pr is 63.2μC/cm 2 under 530 kV/cm applied field,and the effective piezoelectric coefficient d33 is 30 pm/V.展开更多
An expression vector pCBl suitable for rice transformation, harboring a synthesized cecropin B gene and a selectable marker gene (bar), was constructed. It was introduced into immature embryos of two japonica varietie...An expression vector pCBl suitable for rice transformation, harboring a synthesized cecropin B gene and a selectable marker gene (bar), was constructed. It was introduced into immature embryos of two japonica varieties by particle bombardment, and several transgenic plants were obtained. The results from Basta treatment, PCR analysis, dot and Southern blot analysis of cecropin B gene in transgenic plants indicated that both bar and cecropin B gene were integrated into the genome of transformed plants. Northern blot analysis of transgenic plants showed the expression of cecropin B gene at transcriptional level. Some of transgenic plants revealed improved resistances to two types of bacterial diseases, rice bacterial blight and rice bacterial streak to different extent.展开更多
基金Projects(10672139, 10825209, 50872117) supported by the National Natural Science Foundation of ChinaProject(207079) supported by the Key Program of Ministry of Education of China+3 种基金Project(07JJ5002) supported by the Natural Science Foundation of Hunan Province, ChinaProject(08C862) supported by Scientific Research Fund of Hunan Provincial Education Department, ChinaProject([2008]101) supported by Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education MinistryProject([2007]362) supported by Hunan Prestigious Furong Scholar Award, China
文摘Bi0.5(Na0.85K0.15)0.5TiO3(BNKT15) thin films were synthesized by metal-organic decomposition(MOD) at annealing temperatures of 650,680,710 and 740℃,and the effects of annealing temperature on the microstructure,dielectric properties,remnant polarization(2Pr) and leakage current density were studied with X-ray diffractometer,atomic force microscope,precision impedance analyzer,ferroelectric analysis station and semiconductor parameter tester.The results show that the thin film annealed at 710℃ exhibits a typical perovskite structure without predominant orientation and a smooth surface with evenly distributed grains.2Pr value(67.4 μC/cm2 under 830 kV/cm) and the leakage current density(1.6×10-6 A/cm2 at 170 kV/cm) for BNKT15 thin film annealed at 710℃ are better than those for thin films annealed at other temperatures.
基金Projects(10825209,50872117) supported by the National Natural Science Foundation of ChinaProject([2009]17) supported by Changjiang Scholar Incentive Program,China+2 种基金Project([2007]362) supported by Hunan’s Prestigious Furong Scholar Award,ChinaProject supported by Aid Program for Science and Technology Innovative Research Team in Higher Educational Instituions of Hunan Province,ChinaProject(09JJ7004) supported by the Natural Science Foundation of Hunan Province for Innovation Group,China
文摘Bi3.15Nd0.85Ti3O12(BNT) powder and thin film were prepared by metal organic decomposition(MOD) method.The heat flow curve of BNT powder was measured with a modulated temperature differential scanning calorimeter,and thermal physical parameters such as thermal conductivity coefficient and thermal diffusion coefficient were obtained from the heat flow curve.The phase identification,ferroelectric,and piezoelectric properties of BNT thin film annealed at 700°C were investigated with X-ray diffractometer,ferroelectric analyzer,and scanning probe microscope.The results show that the thin films consisting of a single phase of bismuth-layered perovskite are polycrystalline,without a preferred orientation.Remnant polarization 2Pr is 63.2μC/cm 2 under 530 kV/cm applied field,and the effective piezoelectric coefficient d33 is 30 pm/V.
基金Project supported by the Eighth Five-Year-Plan and the Rockefeller Foundation.
文摘An expression vector pCBl suitable for rice transformation, harboring a synthesized cecropin B gene and a selectable marker gene (bar), was constructed. It was introduced into immature embryos of two japonica varieties by particle bombardment, and several transgenic plants were obtained. The results from Basta treatment, PCR analysis, dot and Southern blot analysis of cecropin B gene in transgenic plants indicated that both bar and cecropin B gene were integrated into the genome of transformed plants. Northern blot analysis of transgenic plants showed the expression of cecropin B gene at transcriptional level. Some of transgenic plants revealed improved resistances to two types of bacterial diseases, rice bacterial blight and rice bacterial streak to different extent.
