1 Introduction The Kangdian axis is an important polymetallic metallogenic belt in Southwest China,and it is also an area with a lot of hydrothermal uranium mineralization(Wang Hongjun,et al.,2009.The basic
Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise go...Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.展开更多
A new uranium(Ⅵ)-polycarboxylate framework with honeycomb(6,3) nets {[Zn(phen)_2(H_2O)_2][(UO_2)_2(BDC)_3]·2H_2O}n(1, BDC = benzene-1,4-dicarboxylate) was hydrotherrmally synthesized by the reactio...A new uranium(Ⅵ)-polycarboxylate framework with honeycomb(6,3) nets {[Zn(phen)_2(H_2O)_2][(UO_2)_2(BDC)_3]·2H_2O}n(1, BDC = benzene-1,4-dicarboxylate) was hydrotherrmally synthesized by the reactions of Zn(NO_3)_2·6H_2O with phenanthroine, UO_2(NO_3)_2·6H_2O and benzene-1,4-dicarboxylate. The complex was structurally characterized by FT-IR spectroscopy, powder XRD and X-ray single-crystal diffraction. Crystal data for 1: monoclinic, space group Cc with M_r = 1522.19, a = 14.9385(10), b = 20.4922(13), c = 15.9728(10) ?, β = 100.1240(10)°, V = 4813.5(5) ?~3, Z = 4, D_c = 2.100 g?cm^(–3), μ = 7.293 mm^(–1), F(000) = 2872, the final R = 0.0224 and w R= 0.0677 for 6522 observed reflections with I 〉 2σ(I). Hydrogen bonds and π-π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 3.57 e V indicates its broad gap semiconductor nature. UV-Vis spectra and solid-state luminescence were discussed in detail. The compound exhibits photocatalytic activities for the degradation of rhodamine B.展开更多
基金supported by the China Nuclear Industry Geological Bureau Foundation (No.201637 and 201638)
文摘1 Introduction The Kangdian axis is an important polymetallic metallogenic belt in Southwest China,and it is also an area with a lot of hydrothermal uranium mineralization(Wang Hongjun,et al.,2009.The basic
文摘Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.
基金Financial supports received from the scientific research foundation of Sanming University(No.B201406/Q)Education Scientific Research Project of Fujian Province(No.JA15480)
文摘A new uranium(Ⅵ)-polycarboxylate framework with honeycomb(6,3) nets {[Zn(phen)_2(H_2O)_2][(UO_2)_2(BDC)_3]·2H_2O}n(1, BDC = benzene-1,4-dicarboxylate) was hydrotherrmally synthesized by the reactions of Zn(NO_3)_2·6H_2O with phenanthroine, UO_2(NO_3)_2·6H_2O and benzene-1,4-dicarboxylate. The complex was structurally characterized by FT-IR spectroscopy, powder XRD and X-ray single-crystal diffraction. Crystal data for 1: monoclinic, space group Cc with M_r = 1522.19, a = 14.9385(10), b = 20.4922(13), c = 15.9728(10) ?, β = 100.1240(10)°, V = 4813.5(5) ?~3, Z = 4, D_c = 2.100 g?cm^(–3), μ = 7.293 mm^(–1), F(000) = 2872, the final R = 0.0224 and w R= 0.0677 for 6522 observed reflections with I 〉 2σ(I). Hydrogen bonds and π-π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 3.57 e V indicates its broad gap semiconductor nature. UV-Vis spectra and solid-state luminescence were discussed in detail. The compound exhibits photocatalytic activities for the degradation of rhodamine B.