Polycrystalline silicon （poly-Si） films were prepared by hot-wire chemical vapor deposition （HWCVD） at a low substrate temperature of 525 ℃. The influence of hydrogen on the epitaxial growth of ploy-Si films was ...Polycrystalline silicon （poly-Si） films were prepared by hot-wire chemical vapor deposition （HWCVD） at a low substrate temperature of 525 ℃. The influence of hydrogen on the epitaxial growth of ploy-Si films was investigated. Raman spectra show that the poly-Si films are fully crystallized at 525 ℃ with a different hydrogen dilution ratio （50%-91.7%）. X-ray diffraction, grazing incidence X-ray diffraction and SEM images show that the poly-Si thin films present （100） preferred orientation on （100） c-Si substrate in the high hydrogen dilution condition. The P-type poly-Si film prepared with a hydrogen dilution ratio of 91.7% shows a hall mobility of 8.78 cm2/（V-s） with a carrier concentration of 1.3 × 10^20 cm^-3, which indicates that the epitaxial poly-Si film prepared by HWCVD has the possibility to be used in photovoltaic and TFT devices.展开更多
Rice（Oryza sativa L.）, a tropical and subtropical crop, is susceptible to low temperature stress during seedling, booting, and flowering stages, which leads to lower grain quality levels and decreasing rice yields. ...Rice（Oryza sativa L.）, a tropical and subtropical crop, is susceptible to low temperature stress during seedling, booting, and flowering stages, which leads to lower grain quality levels and decreasing rice yields. Cold tolerance is affected by multiple genetic factors in rice, and the complex genetic mechanisms associated with chilling stress tolerance remain unclear. Here, we detected seven quantitative trait loci（QTLs） for cold tolerance at booting stage and identified one cold tolerant line, SIL157, in an introgression line population derived from a cross between the indica variety Guichao 2, as the recipient, and Dongxiang common wild rice, as the donor. When compared with Guichao 2, SIL157 showed a stronger cold tolerance during different growth stages. Through an integrated strategy that combined QTL-mapping with expression profile analysis, six candidate genes, which were up-regulated under chilling stress at the seedling and booting developmental stages, were studied. The results may help in understanding cold tolerance mechanisms and in using beneficial alleles from wild rice to improve the cold tolerance of rice cultivars through molecular marker-assisted selection.展开更多
基金Project supported by the Beijing City Science and Technology Project(No.D121100001812003)the National Basic Research Program of China(No.2011CBA00705)
文摘Polycrystalline silicon （poly-Si） films were prepared by hot-wire chemical vapor deposition （HWCVD） at a low substrate temperature of 525 ℃. The influence of hydrogen on the epitaxial growth of ploy-Si films was investigated. Raman spectra show that the poly-Si films are fully crystallized at 525 ℃ with a different hydrogen dilution ratio （50%-91.7%）. X-ray diffraction, grazing incidence X-ray diffraction and SEM images show that the poly-Si thin films present （100） preferred orientation on （100） c-Si substrate in the high hydrogen dilution condition. The P-type poly-Si film prepared with a hydrogen dilution ratio of 91.7% shows a hall mobility of 8.78 cm2/（V-s） with a carrier concentration of 1.3 × 10^20 cm^-3, which indicates that the epitaxial poly-Si film prepared by HWCVD has the possibility to be used in photovoltaic and TFT devices.
基金supported by the National Natural Science Foundation of China(31371585 and 30971755)the Beijing Youth Talent,China(31056102)
文摘Rice（Oryza sativa L.）, a tropical and subtropical crop, is susceptible to low temperature stress during seedling, booting, and flowering stages, which leads to lower grain quality levels and decreasing rice yields. Cold tolerance is affected by multiple genetic factors in rice, and the complex genetic mechanisms associated with chilling stress tolerance remain unclear. Here, we detected seven quantitative trait loci（QTLs） for cold tolerance at booting stage and identified one cold tolerant line, SIL157, in an introgression line population derived from a cross between the indica variety Guichao 2, as the recipient, and Dongxiang common wild rice, as the donor. When compared with Guichao 2, SIL157 showed a stronger cold tolerance during different growth stages. Through an integrated strategy that combined QTL-mapping with expression profile analysis, six candidate genes, which were up-regulated under chilling stress at the seedling and booting developmental stages, were studied. The results may help in understanding cold tolerance mechanisms and in using beneficial alleles from wild rice to improve the cold tolerance of rice cultivars through molecular marker-assisted selection.
