Zeolite ZSM 5 membrane, whose permeance was up to 10 -6 mol/(m 2·s·Pa) and a magnitude higher than that of other groups, was prepared on α Al 2O 3 support by multi in situ hydrothermal treatments, using opt...Zeolite ZSM 5 membrane, whose permeance was up to 10 -6 mol/(m 2·s·Pa) and a magnitude higher than that of other groups, was prepared on α Al 2O 3 support by multi in situ hydrothermal treatments, using optimized sol prescription and cheap n butane as the structure directing agent. The membrane was characterized by means of XRD, SEM and single gas permeances measurements, which showed that it was dense and integral without large intercrystal pores and cracks. The permeance of H 2, N 2, C 3H 8 and n C 4H 10 was up to 2.35×10 -6 , 1.0×10 -6 , 1.13×10 -7 and 4.9×10 -8 mol/(m 2·s·Pa), respectively. Ideal selectivity of H 2/N 2, H 2/C 3H 8 and H 2/ n C 4H 10 was 2.45, 20.8 and 48, respectively. [WT5HZ]展开更多
A complex of lanthanides formulated as [La( p-OHC6H4CH2COO)3(phen)]2 was prepared from the water/ ethanol solution under normal temperturate with 8-hydroxyquinoline as the acidity conditionor,the complex was character...A complex of lanthanides formulated as [La( p-OHC6H4CH2COO)3(phen)]2 was prepared from the water/ ethanol solution under normal temperturate with 8-hydroxyquinoline as the acidity conditionor,the complex was characterized by elemental analysis,IR,1H NMR spectroscopy and X-ray crystal structure analysis. The crystal belongs to monoclinic crystal system,space group P21/n. The 1,10-phenanthroline and 4-hydroxyphenylacetic ligands coordinated to the center ion through O or N atoms. The structural feature of the complex were discussed.展开更多
将松弛时间较长的聚对苯二甲酸乙二醇酯(PET)动态挤出后淬火"冷冻"其熔体的分子链缠结状态,然后在差示扫描量热仪(DSC)上升温到玻璃化转变温度以上进行结晶。通过分析 PET 熔体的动态流变参数和结晶动力学过程的变化,间接证...将松弛时间较长的聚对苯二甲酸乙二醇酯(PET)动态挤出后淬火"冷冻"其熔体的分子链缠结状态,然后在差示扫描量热仪(DSC)上升温到玻璃化转变温度以上进行结晶。通过分析 PET 熔体的动态流变参数和结晶动力学过程的变化,间接证实动态挤出聚合物熔体分子的解缠结作用。结果发现,正弦脉动挤出流场对聚合物分子链造成的解缠结效果不仅可以降低聚合物熔体的加工黏度,还可以明显降低 PET 的结晶温度,结晶峰向低温移动且次峰强度明显增大,低温结晶峰含量随振幅和频率的增加而增大,在振幅为0.3 mm、频率为12 Hz 时达到60.7%,成为主结晶过程。展开更多
The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form...The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form monoclinic crystal with space group P 2 1/ c . The crystal data Dy: a =1 8564(3)[1 8857(2)] nm, b =0 9769(2) [0 9834(1)] nm, c =2 1863(6)[2 2008(7)] nm, β =96 08(2)[95 72(2)]°, V =3 942(1)[4 061(1)] nm 3, Z =4. Dy 3+ [La 3+ ] is coordinated through three carbonyls of the three organic ligands and the three nitrates are all bidentate. So each Dy 3+ [La 3+ ] is coordinated by nine oxygen atoms which form a distorted tricapped trigonal prism.展开更多
The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method....The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method.The results show that the irregular shapes of ice crystals and large population of small ice particles in cirrus are responsible forthe rare occurrence of halos.展开更多
文摘Zeolite ZSM 5 membrane, whose permeance was up to 10 -6 mol/(m 2·s·Pa) and a magnitude higher than that of other groups, was prepared on α Al 2O 3 support by multi in situ hydrothermal treatments, using optimized sol prescription and cheap n butane as the structure directing agent. The membrane was characterized by means of XRD, SEM and single gas permeances measurements, which showed that it was dense and integral without large intercrystal pores and cracks. The permeance of H 2, N 2, C 3H 8 and n C 4H 10 was up to 2.35×10 -6 , 1.0×10 -6 , 1.13×10 -7 and 4.9×10 -8 mol/(m 2·s·Pa), respectively. Ideal selectivity of H 2/N 2, H 2/C 3H 8 and H 2/ n C 4H 10 was 2.45, 20.8 and 48, respectively. [WT5HZ]
文摘A complex of lanthanides formulated as [La( p-OHC6H4CH2COO)3(phen)]2 was prepared from the water/ ethanol solution under normal temperturate with 8-hydroxyquinoline as the acidity conditionor,the complex was characterized by elemental analysis,IR,1H NMR spectroscopy and X-ray crystal structure analysis. The crystal belongs to monoclinic crystal system,space group P21/n. The 1,10-phenanthroline and 4-hydroxyphenylacetic ligands coordinated to the center ion through O or N atoms. The structural feature of the complex were discussed.
文摘将松弛时间较长的聚对苯二甲酸乙二醇酯(PET)动态挤出后淬火"冷冻"其熔体的分子链缠结状态,然后在差示扫描量热仪(DSC)上升温到玻璃化转变温度以上进行结晶。通过分析 PET 熔体的动态流变参数和结晶动力学过程的变化,间接证实动态挤出聚合物熔体分子的解缠结作用。结果发现,正弦脉动挤出流场对聚合物分子链造成的解缠结效果不仅可以降低聚合物熔体的加工黏度,还可以明显降低 PET 的结晶温度,结晶峰向低温移动且次峰强度明显增大,低温结晶峰含量随振幅和频率的增加而增大,在振幅为0.3 mm、频率为12 Hz 时达到60.7%,成为主结晶过程。
文摘The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form monoclinic crystal with space group P 2 1/ c . The crystal data Dy: a =1 8564(3)[1 8857(2)] nm, b =0 9769(2) [0 9834(1)] nm, c =2 1863(6)[2 2008(7)] nm, β =96 08(2)[95 72(2)]°, V =3 942(1)[4 061(1)] nm 3, Z =4. Dy 3+ [La 3+ ] is coordinated through three carbonyls of the three organic ligands and the three nitrates are all bidentate. So each Dy 3+ [La 3+ ] is coordinated by nine oxygen atoms which form a distorted tricapped trigonal prism.
文摘The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method.The results show that the irregular shapes of ice crystals and large population of small ice particles in cirrus are responsible forthe rare occurrence of halos.
