The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These d...The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These deposits were formed as the result of late mobilization, transportation and concentfation of the previously enriched ore-forming mate- rials in several ore-bearing formations formed during the rift stage. So the metallogeny of these deposits in the rift shows both inheritance and new generation of the ore-forming materials. In future ore-searching practice, attentions should be paid on the studies of the ore-bearing formations in the rift, on the multiple stages of metallogeny and and on multiple derivations of the ore-forming materials.展开更多
利用室温下弛豫铁电单晶0.93Pb(Zn1/3Nb2/3)O3-0.07PbTiO3的材料参数,计算了[001]c极化PZN-7%PT晶体中的声表面波传播特性。结果表明,[001]c极化0.93Pb(Zn1/3Nb2/3)O3-0.07Pb TiO3单晶具有明显优于传统压电材料的声表面波特性。0.93Pb(Z...利用室温下弛豫铁电单晶0.93Pb(Zn1/3Nb2/3)O3-0.07PbTiO3的材料参数,计算了[001]c极化PZN-7%PT晶体中的声表面波传播特性。结果表明,[001]c极化0.93Pb(Zn1/3Nb2/3)O3-0.07Pb TiO3单晶具有明显优于传统压电材料的声表面波特性。0.93Pb(Zn1/3Nb2/3)O3-0.07Pb Ti O3单晶的声表面波特性随着传播方向发生明显的变化。综合考虑晶体的三种声表面波特性,发现Y切型晶体的综合声表面波性能最好,声表面波机电耦合系数k2值较大,能流角和声表面波自由表面相速度值较小,有望应用于下一代低频声表面波设备中。展开更多
Along with windblown dust, large quantities of pollutants are annually brought out of the continental by the westerlies in winter and spring; thereafter they are partly subjected to transport by northeastern monsoon w...Along with windblown dust, large quantities of pollutants are annually brought out of the continental by the westerlies in winter and spring; thereafter they are partly subjected to transport by northeastern monsoon winds to Taiwan. Both PM10 and PM2.5 aerosols collected from northern Taiwan from February 2002 to March 2003 were determined for three heavy metals, namely Pb, Cd and Zn, to characterize the heavy metal compositions between long-range transported and local aerosols and to evaluate their contributions of long-range transport during the northeastern monsoon season. Low Cd/Pb (0.017) and Zn/Pb (1.82) ratios were measured in aerosols during the Asian dust period, in which the sources of ambient aerosols are dominated by long-range transport. By contrast, high Cd/Pb(0.030) and Zn/Pb (3.44) ratios were measured during the summer monsoon season, in which local pollutant emissions dominate the sources of heavy metals. Such characteristic Cd/Pb and Zn/Pb ratios appear to be successfully applied to identify the pollutants originated from the long-range transport or local emissions.展开更多
The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-(Zn) deposits ...The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-(Zn) deposits around this intrusion. Those deposits are spatially associated with the Habo alkaline intrusion. (1) The δ^34S values of sulfides from Au deposits range from -1.91‰ to 2.69 ‰, which are similar to those of Pb-(Zn) deposits (-3.82 ‰ to -0.05 ‰) and both indicate a much greater contribution from magma. (2) The Habo alkaline intrusion has relatively homogeneous Pb isotopic compositions with ^206pb/^204pb ranging from 18.608 to 18.761, ^207pb/^204pb from 15.572 to 15.722 and ^20spb/^204pb from 38.599 to 39.110. These Pb isotope ratios are similar to those of Au deposits, whose ^206pb/^204pb range from 18.564 to 18.734, ^20Tpb/^20apb from 15.582 to 15.738 and ^208pb/^204pb from 38.592 to 39.319. Pb ratios in both the intrusion and Au deposits suggest that Pb mainly derived from the depth, probably represents a mixture of mantle and crust. Pb-(Zn) deposits, however, show a decentralized trait, and most of them are similar to that of the alkaline intrusion with ^206pb/^204pb ranging from 18.523 to 18.648, ^207pb/^204pb from 15.599 to 15.802, and ^20spb/^204pb from 38.659 to 39.206. (3) In the plumbotectonic diagram ^20Tpb/^204pb versus ^206pb/^204pb, almost all of Au and Pb-(Zn) deposits have the same projection area with the Habo alkaline intrusion, which indicates that those deposits almost share the same source with the alkaline intrusion. (4) Isotopic age of the Habo alkaline intrusion is 36-33 Ma, which is similar to that of Beiya, whose ore- related alkaline porphyries age is 38-31 Ma and molybdenite Re-Os age is 36.9 Ma. Therefore, along with S-Pb isotope traits, we suggest that the Habo Au and Pb-(Zn) deposits should be typically Ailaoshan-Red RiverCenozoicalkaline-related deposits and ore-forming ages of these deposits should be later than that of the Habo alkaline intrusion.展开更多
文摘The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These deposits were formed as the result of late mobilization, transportation and concentfation of the previously enriched ore-forming mate- rials in several ore-bearing formations formed during the rift stage. So the metallogeny of these deposits in the rift shows both inheritance and new generation of the ore-forming materials. In future ore-searching practice, attentions should be paid on the studies of the ore-bearing formations in the rift, on the multiple stages of metallogeny and and on multiple derivations of the ore-forming materials.
文摘利用室温下弛豫铁电单晶0.93Pb(Zn1/3Nb2/3)O3-0.07PbTiO3的材料参数,计算了[001]c极化PZN-7%PT晶体中的声表面波传播特性。结果表明,[001]c极化0.93Pb(Zn1/3Nb2/3)O3-0.07Pb TiO3单晶具有明显优于传统压电材料的声表面波特性。0.93Pb(Zn1/3Nb2/3)O3-0.07Pb Ti O3单晶的声表面波特性随着传播方向发生明显的变化。综合考虑晶体的三种声表面波特性,发现Y切型晶体的综合声表面波性能最好,声表面波机电耦合系数k2值较大,能流角和声表面波自由表面相速度值较小,有望应用于下一代低频声表面波设备中。
文摘Along with windblown dust, large quantities of pollutants are annually brought out of the continental by the westerlies in winter and spring; thereafter they are partly subjected to transport by northeastern monsoon winds to Taiwan. Both PM10 and PM2.5 aerosols collected from northern Taiwan from February 2002 to March 2003 were determined for three heavy metals, namely Pb, Cd and Zn, to characterize the heavy metal compositions between long-range transported and local aerosols and to evaluate their contributions of long-range transport during the northeastern monsoon season. Low Cd/Pb (0.017) and Zn/Pb (1.82) ratios were measured in aerosols during the Asian dust period, in which the sources of ambient aerosols are dominated by long-range transport. By contrast, high Cd/Pb(0.030) and Zn/Pb (3.44) ratios were measured during the summer monsoon season, in which local pollutant emissions dominate the sources of heavy metals. Such characteristic Cd/Pb and Zn/Pb ratios appear to be successfully applied to identify the pollutants originated from the long-range transport or local emissions.
文摘The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-(Zn) deposits around this intrusion. Those deposits are spatially associated with the Habo alkaline intrusion. (1) The δ^34S values of sulfides from Au deposits range from -1.91‰ to 2.69 ‰, which are similar to those of Pb-(Zn) deposits (-3.82 ‰ to -0.05 ‰) and both indicate a much greater contribution from magma. (2) The Habo alkaline intrusion has relatively homogeneous Pb isotopic compositions with ^206pb/^204pb ranging from 18.608 to 18.761, ^207pb/^204pb from 15.572 to 15.722 and ^20spb/^204pb from 38.599 to 39.110. These Pb isotope ratios are similar to those of Au deposits, whose ^206pb/^204pb range from 18.564 to 18.734, ^20Tpb/^20apb from 15.582 to 15.738 and ^208pb/^204pb from 38.592 to 39.319. Pb ratios in both the intrusion and Au deposits suggest that Pb mainly derived from the depth, probably represents a mixture of mantle and crust. Pb-(Zn) deposits, however, show a decentralized trait, and most of them are similar to that of the alkaline intrusion with ^206pb/^204pb ranging from 18.523 to 18.648, ^207pb/^204pb from 15.599 to 15.802, and ^20spb/^204pb from 38.659 to 39.206. (3) In the plumbotectonic diagram ^20Tpb/^204pb versus ^206pb/^204pb, almost all of Au and Pb-(Zn) deposits have the same projection area with the Habo alkaline intrusion, which indicates that those deposits almost share the same source with the alkaline intrusion. (4) Isotopic age of the Habo alkaline intrusion is 36-33 Ma, which is similar to that of Beiya, whose ore- related alkaline porphyries age is 38-31 Ma and molybdenite Re-Os age is 36.9 Ma. Therefore, along with S-Pb isotope traits, we suggest that the Habo Au and Pb-(Zn) deposits should be typically Ailaoshan-Red RiverCenozoicalkaline-related deposits and ore-forming ages of these deposits should be later than that of the Habo alkaline intrusion.