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151.
德州气候变化与建筑物防腐 总被引:2,自引:0,他引:2
利用德州11县市1951~2005年温度、降水资料,计算气候干燥度,1981~2005年与1951~1980年相比全市干燥度由1.45增大到1.64,已由原来的半湿润气候变化为半干旱气候。各县市降水量呈减少趋势,平均每10年减少19.64mm;气温呈上升趋势,平均每10年升高0.11℃,冬季升高0.30℃,冬季增温显著,北部县市已由原来的冰冻区变化为微冻区,全市均为微冻区。由于气候条件变化,相应场地环境类别与腐蚀介质指标的调整系数标准应作调整改变,场地环境类别由Ⅱ类转变为Ⅰ类,腐蚀介质指标的调整系数均取0.9。 相似文献
152.
153.
154.
In this work,we studied the variable stars in the open cluster NGC 1912 based on the photometric observations and Gaia DR2 data.More than 3600 CCD frames in B,V,R filters were reduced,and we obtained the light curves that span about 63 hours.By analyzing these light curves,we detected 24 variable stars,including 16 periodic variable stars,seven eclipsing binaries and one star whose type is unclear.Among these 24 variable stars,11 are newly discovered,which are classified as sixγDoradus stars,oneδScuti star,three detached binaries and one contact binary.We also confirmed 13 previously known variable stars.Based on cluster members identified by Cantat-Gaudin et al.(2018),we inferred cluster memberships for these detected variable stars.Using Gaia DR2 data,we plotted a new color-magnitude diagram for NGC1912,and showed the nature of variable cluster members in kinematical properties and heliocentric distance.Among the 24 variable stars,seven variables are probable cluster members,which show homogeneity in kinematic characters and space position with the established cluster members.Four of the seven variable cluster members are the previously discovered stars,consisting of twoγDor stars and twoδSct stars.The remaining three variable cluster members,which are allγDor stars,are firstly detected in this work.The main physical parameters of these variable cluster members estimated from the color-magnitude diagram are log(age/yr)=8.75,[Fe/H]=-0.1,m-M=10.03 mag,and E(B-V)=0.307. 相似文献
155.
156.
延边地区天宝山多金属矿田的流体特征与成矿模式 总被引:4,自引:0,他引:4
天宝山铅锌铜钼多金属矿田由新兴铅-锌矿床、东风铅-锌-铜-钼矿床和立山铜-铅-锌矿床组成,它们分别产在侏罗纪黑云母花岗闪长岩、闪长岩与古生代海相火山-沉积岩的接触带和岩体内部。矿床地质特征研究表明:新兴铅-锌矿床以石英硫化物充填胶结角砾岩筒矿体为特征,具有与中温岩浆热液矿床类似的蚀变特征;东风铅-锌-铜-钼矿床以发育浸染状硫化物、石英硫化物脉和辉钼矿石英脉为特征,具有接触交代热液矿床特征;立山铜-铅-锌矿床则以磁铁矿、方铅矿和闪锌矿等多金属硫化物矿化发育为特征,具有典型的接触交代矽卡岩型矿床特征。对主成矿阶段以及成矿晚阶段的脉石矿物石英流体包裹体研究揭示:新兴铅-锌矿床的石英-黄铁矿阶段、石英-闪锌矿-方铅矿-黄铜矿多金属硫化物阶段和石英-碳酸盐阶段对应的温度分别为270~340℃、190~260℃、130~160℃;盐度(w(NaCl))和密度分别为0.62%~9.86%和0.37~1.00g/cm3;压力为37.31~87.69MPa;激光拉曼光谱分析获得流体包裹体的成分主要为CO2、H2O,含有少量的CH4和N2。东风铅-锌-铜-钼矿床的石英-辉钼矿阶段、石英-闪锌矿-方铅矿-黄铜矿多金属硫化物阶段和石英-碳酸盐阶段对应的温度分别为280~337℃、200~260℃、101~190℃;盐度和密度分别为7.16%~23.95%和0.96~1.12g/cm3;压力为28.23~56.64MPa;激光拉曼光谱分析获得流体包裹体成分为H2O。立山铜-铅-锌矿床的磁铁矿-石英脉阶段、石英-方铅矿-闪锌矿-黄铜矿等多金属硫化物和石英-碳酸盐阶段对应的温度分别为210~240℃、170~200℃、126~160℃,盐度和密度分别为2.07%~9.47%和0.89~0.92g/cm3;压力为33.88~59.72 MPa;激光拉曼光谱分析获得流体包裹体成分为CO2和CH4。基于矿床地质特征、成矿流体性质和来源等方面的讨论,建立了天宝山多金属矿田的成矿模式。 相似文献
157.
Song Xuexin 《Mineralium Deposita》1984,19(2):95-104
The Fankou Pb-Zn deposit occurs in the Middle-Upper Devonian and Lower Carboniferous carbonate and argillaceous carbonate formations. In principle, the deposit can be classified as a carbonate-hosted strate-bound deposit. Representative sphalerite, galena, and pyrite separates from Fankou have been analysed. For the purpose of comparison a literature survey on minor elements of other districts have been carried out. The comparison of determined data with the quoted data shows that the Fankou sphalerites are rich in Ga, Ge and Ag, but poor in Se and Te; the Fankou galenas are rich in Ag, Hg, Sb and As, but poor in Se, Te, Tl and Bi; the Fankou pyrites are rich in As, Cd and In, but poor in Se, Te, Co and Ni. Zn/Cd and Se/S×10–4 ratios for sphalerites, Sb/Ag, Sb/Bi and Se/S×10–4 ratios for galenas and Co/Ni ratios for pyrites from Fankou and other districts have been calculated. Ga-Ge-Ag atomic ratios in sphalerites, Sb-Bi-Ag atomic ratios in galenas and Co-Ni relations in pyrites have been plotted. The average value (311) of Zn/Cd ratios for sphalerites from Fankou is similar to values of sphalerites from Gaobanhe, Heqing, Accesa and Broken Hill. The average Sb/Ag ratio (0.74) and the Sb-Bi-Ag atomic ratios in Fankou galenas are similar to those in the syngenetic galena from the British Island. The Ga-Ge-Ag atomic ratios for Fankou sphalerites are similar to those for the syngenetic sphalerites and Gorno sphalerites. The average Co/Ni ratio (1.1) for micro to fine-grained pyrites from Fankou laminated-bedded pyrite ore is similar to that (0.8) for the sedimentary pyrites from other districts. As to the fine to medium-grained pyrites from Fankou massive pyritic ores, their higher Co/Ni ratios (1.6–1.8) may relate to the fact that more Ni is lost than Co, during the reformation or recrystallization. Sphalerite, galena and pyrite from Fankou all are rather poor in Se and have very low values of Se/S×10–4, so they may bear no genetic relation to volcanism. To sum up, the following conclusions can be reached: (1) The Fankou deposit possesses some syngenetic features. (2) Evidently it differs from skarn type, hydrothermal type, and volcanogenic type deposits. (3) Surely it is a reformed sedimentary Pb-Zn deposit. 相似文献
158.
CH4 inclusions in orogenic harzburgite: Evidence for reduced slab fluids and implication for redox melting in mantle wedge 总被引:3,自引:0,他引:3
Fluids released from the subducting oceanic lithosphere are generally accepted to cause mantle wedge peridotite melting that produces arc magmas. These fluids have long been considered to be dominated by highly oxidized H2O and CO2 as inferred from erupted arc lavas. This inference is also consistent with the geochemistry of peridotite xenoliths in some arc basalts. However, the exact nature of these fluids in the mantle wedge melting region is unknown. Here, we report observations of abundant CH4 + C + H2 fluid inclusions in olivine of a fresh orogenic harzburgite in the Early Paleozoic Qilian suture zone in Northwest China. The petrotectonic association suggests that this harzburgite body represents a remnant of a Paleozoic mantle wedge exhumed subsequently in response to the tectonic collision. The mineralogy, mineral compositions and bulk-rock trace element systematics of the harzburgite corroborate further that the harzburgite represents a high-degree melting residue in a mantle wedge environment. Furthermore, existing and new C, He, Ne and Ar isotopes of these fluid inclusions are consistent with their being of shallow (i.e., crustal vs. deep mantle) origin, likely released from serpentinized peridotites and sediments of the subducting oceanic lithosphere. These observations, if common to subduction systems, provide additional perspectives on mantle wedge melting and subduction-zone magmatism. That is, mantle wedge melting may in some cases be triggered by redox reactions; the highly reduced (∼ΔFMQ-5, i.e., 5 log units below the fayalite-magnetite-quartz oxygen fugacity buffer) CH4-rich fluids released from the subducting slab interact with the relatively oxidized (∼ΔFMQ-1) mantle wedge peridotite, producing H2O and CO2 that then lowers the solidus and incites partial melting for arc magmatism. The significance of slab-component contribution to the geochemistry of arc magmatism would depend on elemental selection and solubility in highly reduced fluids, for which experimental data are needed. We do not advocate the above to be the primary mechanism of arc magmatism, but we do suggest that the observed highly reduced fluids are present in mantle wedge peridotites and their potential roles in arc magmatism need attention. 相似文献
159.
INTRODUCTION The properties of phosphor usedin a plasma dis-play panel (PDP) affect the performance of the PDP(Okazaki et al .,2000 ; Rao and Devine ,2000) . Theluminescent properties of the phosphor are decided bythe morphology ,particle size and size distribution ofthe powder ,sothe requirements for the powder mor-phology are high in a color PDP which belongs to ahigh resolution display apparatus (I m et al .,2005 ;Yang et al ., 2005) . Studies have shown that withsmall particle si… 相似文献
160.
TBP萃淋树脂微色谱柱分离富集钼的研究及应用 总被引:3,自引:0,他引:3
研究了TBP萃淋树脂微色谱柱分离富集微量钼的柱性能,确定了分离钼的最佳条件。在减压条件下,运用零空床体积洗脱技术,以3mol/LHCl为上柱介质,0.5mol/LHCl洗脱,可使钼(VI)与钨(Ⅵ)、铁(Ⅲ)、锡(Ⅳ)等干扰离子快速分离,采用邻氯苯基荧光酮胶束增溶光度法,测定矿石中微量钼,结果满意。 相似文献