In the present paper, the concentration effect of near-infrared quantum cutting of Tm3＋ ion in （Y1-xTmx）3Al5Ol2 powder phosphor is studied by means of experiments and calculations. In addition, the absorption spect...In the present paper, the concentration effect of near-infrared quantum cutting of Tm3＋ ion in （Y1-xTmx）3Al5Ol2 powder phosphor is studied by means of experiments and calculations. In addition, the absorption spectra, visible-to-near- infrared excitation and emission spectra, and fluorescence lifetimes are measured. It is found that （Y1-xTmx）3Al5O12 powder phosphor has a strong four-photon near-infrared quantum cutting luminescence of 1788.0-nm 3F4 →3H6 fluores- cence of Tm3＋ ion, when excited by 357.0-nm light. It is also found that the up-limit of the four-photon near-infrared quantum cutting luminescence efficiency of （Yo.700Tmo.300）3Al5 O12 powder phosphor is approximately 302.19%. To the knowledge of the authors, this is the first time that a near-infrared quantum cutting efficiency up-limit exceeding 300% has been reported. The results of this manuscript are valuable in aiding the probing of the new generation Ge solar cell.展开更多
Cavitation erosion behavior of as-welded Cu12Mn8Al3Fe2Ni alloy in 3.5% NaCl aqueous solution was studied bymagnetostrictive vibratory device for cavitation erosion. The results show that the cavitation erosion resista...Cavitation erosion behavior of as-welded Cu12Mn8Al3Fe2Ni alloy in 3.5% NaCl aqueous solution was studied bymagnetostrictive vibratory device for cavitation erosion. The results show that the cavitation erosion resistance ofthe as-welded Cu12Mn8Al3Fe2Ni alloy is much more superior to that of the as-cast one. The cumulative mass lossand the mass loss rate of the as-welded Cu12Mn8Al3Fe2Ni alloy are almost 1/4 that of the as-cast one. SEM analysisof eroded specimens reveals that the as-cast Cu12Mn8Al3Fe2Ni alloy is attacked more severely than the as-weldedone. Microcracks causing cavitation damage initiate at the phase boundaries.展开更多
New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbony...New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbonyl (Fe3(CO)12). These thin films, composed of sintered elemental Fe nanoparticles of 4.1 ± 0.7 nm diameter, are protected from air oxidation by a very thin carbon layer. The saturation magnetization of these thin Fe coatings was found to be close to that of bulk iron. The electrical resistivity behavior of the ferromagnetic thin films is similar to that of a semiconductor. In the present manuscript, these Fe thin coatings on Si wafers have been used as a catalyst for synthesizing crystalline carbon nanotubes (CNTs), by CVD using ethylene as a carbon precursor.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.10674019)the Significant Project of Fundamental Research Funds for the Central Universities of China(Grant No.212-105560GK)
文摘In the present paper, the concentration effect of near-infrared quantum cutting of Tm3＋ ion in （Y1-xTmx）3Al5Ol2 powder phosphor is studied by means of experiments and calculations. In addition, the absorption spectra, visible-to-near- infrared excitation and emission spectra, and fluorescence lifetimes are measured. It is found that （Y1-xTmx）3Al5O12 powder phosphor has a strong four-photon near-infrared quantum cutting luminescence of 1788.0-nm 3F4 →3H6 fluores- cence of Tm3＋ ion, when excited by 357.0-nm light. It is also found that the up-limit of the four-photon near-infrared quantum cutting luminescence efficiency of （Yo.700Tmo.300）3Al5 O12 powder phosphor is approximately 302.19%. To the knowledge of the authors, this is the first time that a near-infrared quantum cutting efficiency up-limit exceeding 300% has been reported. The results of this manuscript are valuable in aiding the probing of the new generation Ge solar cell.
文摘Cavitation erosion behavior of as-welded Cu12Mn8Al3Fe2Ni alloy in 3.5% NaCl aqueous solution was studied bymagnetostrictive vibratory device for cavitation erosion. The results show that the cavitation erosion resistance ofthe as-welded Cu12Mn8Al3Fe2Ni alloy is much more superior to that of the as-cast one. The cumulative mass lossand the mass loss rate of the as-welded Cu12Mn8Al3Fe2Ni alloy are almost 1/4 that of the as-cast one. SEM analysisof eroded specimens reveals that the as-cast Cu12Mn8Al3Fe2Ni alloy is attacked more severely than the as-weldedone. Microcracks causing cavitation damage initiate at the phase boundaries.
文摘New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbonyl (Fe3(CO)12). These thin films, composed of sintered elemental Fe nanoparticles of 4.1 ± 0.7 nm diameter, are protected from air oxidation by a very thin carbon layer. The saturation magnetization of these thin Fe coatings was found to be close to that of bulk iron. The electrical resistivity behavior of the ferromagnetic thin films is similar to that of a semiconductor. In the present manuscript, these Fe thin coatings on Si wafers have been used as a catalyst for synthesizing crystalline carbon nanotubes (CNTs), by CVD using ethylene as a carbon precursor.
