A single crystal of Li3Ba2Ho3(WO4)8 was obtained from a flux of Li2WO4 under an air atmosphere. The structure of the pure crystal was determined by single-crystal X-ray diffraction method. It crystallizes in the mon...A single crystal of Li3Ba2Ho3(WO4)8 was obtained from a flux of Li2WO4 under an air atmosphere. The structure of the pure crystal was determined by single-crystal X-ray diffraction method. It crystallizes in the monoclinic system, space group C2/c with a = 5.240(4), b = 12.790(10), c = 19.247(15), β = 91.921(15)°, V = 1289.1(18)3, Z = 2, Mr = 2773.09, Dc = 7.144 g/cm3, μ = 47.732 mm-1, Rint = 0.0693, F(000) = 2340, the final R = 0.0472 and wR = 0.1221 for 1535 observed reflections (I 2σ(I)). The Li3Ba2Ho3(WO4)8 has a high structure disorder with one 8f site shared by Li(1) and Ho ions with occupancy of 0.25 and 0.75, respectively. The fundamental structure is constituted by distorted square antiprisms Ho/Li(1)O8 with C1 symmetry, distorted Li(2)O6 octahedra and BaO10 polyhedra. The optical properties were investigated by IR and absorption spectroscopy, and the emission cross sections and gain cross sections of 5I7 → 5I8 of Ho3+ were calculated.展开更多
设计了一种具有辅助电加热和均流孔板的水/相变材料复合蓄热式水箱,该水箱以封装有复合八水氢氧化钡的相变蓄热球作为储热单元。理论分析了相变蓄热球应用于复合蓄热式水箱中的可行性,实验研究了水箱中有无相变蓄热球、恒定流量下的直...设计了一种具有辅助电加热和均流孔板的水/相变材料复合蓄热式水箱,该水箱以封装有复合八水氢氧化钡的相变蓄热球作为储热单元。理论分析了相变蓄热球应用于复合蓄热式水箱中的可行性,实验研究了水箱中有无相变蓄热球、恒定流量下的直接和恒温蓄放热特性,结果表明:均流孔板的应用,可使冷热水在水箱底部均匀混合,使高温热水出水量达到最大;在热水出水流量为3.3 L/min时,添加60个相变蓄热球的复合蓄热式水箱比纯水箱可多制得10 L 60℃以上的热水;在热水出水流量为1.6 L/min时,添加120个相变蓄热球的复合蓄热式水箱比纯水箱可多制得40 L 40℃的恒温热水。展开更多
基金supported by the National Natural Science Foundation of China(20971123,51002153,21007070,51102232,61106004 and 21103191)
文摘A single crystal of Li3Ba2Ho3(WO4)8 was obtained from a flux of Li2WO4 under an air atmosphere. The structure of the pure crystal was determined by single-crystal X-ray diffraction method. It crystallizes in the monoclinic system, space group C2/c with a = 5.240(4), b = 12.790(10), c = 19.247(15), β = 91.921(15)°, V = 1289.1(18)3, Z = 2, Mr = 2773.09, Dc = 7.144 g/cm3, μ = 47.732 mm-1, Rint = 0.0693, F(000) = 2340, the final R = 0.0472 and wR = 0.1221 for 1535 observed reflections (I 2σ(I)). The Li3Ba2Ho3(WO4)8 has a high structure disorder with one 8f site shared by Li(1) and Ho ions with occupancy of 0.25 and 0.75, respectively. The fundamental structure is constituted by distorted square antiprisms Ho/Li(1)O8 with C1 symmetry, distorted Li(2)O6 octahedra and BaO10 polyhedra. The optical properties were investigated by IR and absorption spectroscopy, and the emission cross sections and gain cross sections of 5I7 → 5I8 of Ho3+ were calculated.
文摘设计了一种具有辅助电加热和均流孔板的水/相变材料复合蓄热式水箱,该水箱以封装有复合八水氢氧化钡的相变蓄热球作为储热单元。理论分析了相变蓄热球应用于复合蓄热式水箱中的可行性,实验研究了水箱中有无相变蓄热球、恒定流量下的直接和恒温蓄放热特性,结果表明:均流孔板的应用,可使冷热水在水箱底部均匀混合,使高温热水出水量达到最大;在热水出水流量为3.3 L/min时,添加60个相变蓄热球的复合蓄热式水箱比纯水箱可多制得10 L 60℃以上的热水;在热水出水流量为1.6 L/min时,添加120个相变蓄热球的复合蓄热式水箱比纯水箱可多制得40 L 40℃的恒温热水。