The rare earth pentaphosphates (LnP 5O 14 ) is a kind of functional crysta l with chemical stoichiometry.They have received considerable attention and th e i r crystal growth,structure,absorption and fluorescence spec...The rare earth pentaphosphates (LnP 5O 14 ) is a kind of functional crysta l with chemical stoichiometry.They have received considerable attention and th e i r crystal growth,structure,absorption and fluorescence spectra,infrared and Rama n spectra,ferroelectric and magnetic properties had been studied.TbP 5O 14 can emit strong green fluorescence.It might be a kind of new crystal luminescenc e material.In order to search for new luminescence material of plasma display pa nels (PDP),we have studied the VUV spectra of TbP 5O 14 . TbP 5O 14 crystals were made by evaporation solution method.The usual expe rimental condition is as follows:展开更多
We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the ob...We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the observations are 159 × 87 and 1.7K, respectively. The main results are: (1) the lunar brightness temperature averaged over the whole disk is about 233K while the average brightness temperature for the four quadrants are 228.1K (NE), 239.7K (NW), 233.9K (SW) and 228.8K (SE). The observations reveal large temperature and spatial variations on the Moon for the first time. The highest brightness temperature is about 257 K and it is located along the lunar equator, to the west. The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of po- larization is about 6%. Both polarization intensity and degree of polarization increase from the disk’s center to the limb, and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith, such as dielectric constant and thickness distribution. The results show that the lunar regolith’s thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.展开更多
近日，关于“国内交友网站UUMe成功获得美国两大顶级风险投资融资”的新闻引起了业界的强烈关注。尽管随着全球和国内第二轮互联网浪潮的袭来，一些颇具实力的网站获得外国风险投资的消息不时传出，可是作为世界五大风险投资公司之一、...近日，关于“国内交友网站UUMe成功获得美国两大顶级风险投资融资”的新闻引起了业界的强烈关注。尽管随着全球和国内第二轮互联网浪潮的袭来，一些颇具实力的网站获得外国风险投资的消息不时传出，可是作为世界五大风险投资公司之一、并且从未在中国进行过投资的Accel Partners，和顶级的资金管理公司DCM(Doll Capital Manaqement)。展开更多
文摘The rare earth pentaphosphates (LnP 5O 14 ) is a kind of functional crysta l with chemical stoichiometry.They have received considerable attention and th e i r crystal growth,structure,absorption and fluorescence spectra,infrared and Rama n spectra,ferroelectric and magnetic properties had been studied.TbP 5O 14 can emit strong green fluorescence.It might be a kind of new crystal luminescenc e material.In order to search for new luminescence material of plasma display pa nels (PDP),we have studied the VUV spectra of TbP 5O 14 . TbP 5O 14 crystals were made by evaporation solution method.The usual expe rimental condition is as follows:
基金the National High-tech R&D Program of China (863 Program, No. 2008AA12A212)
文摘We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the observations are 159 × 87 and 1.7K, respectively. The main results are: (1) the lunar brightness temperature averaged over the whole disk is about 233K while the average brightness temperature for the four quadrants are 228.1K (NE), 239.7K (NW), 233.9K (SW) and 228.8K (SE). The observations reveal large temperature and spatial variations on the Moon for the first time. The highest brightness temperature is about 257 K and it is located along the lunar equator, to the west. The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of po- larization is about 6%. Both polarization intensity and degree of polarization increase from the disk’s center to the limb, and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith, such as dielectric constant and thickness distribution. The results show that the lunar regolith’s thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.
文摘近日，关于“国内交友网站UUMe成功获得美国两大顶级风险投资融资”的新闻引起了业界的强烈关注。尽管随着全球和国内第二轮互联网浪潮的袭来，一些颇具实力的网站获得外国风险投资的消息不时传出，可是作为世界五大风险投资公司之一、并且从未在中国进行过投资的Accel Partners，和顶级的资金管理公司DCM(Doll Capital Manaqement)。
