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71.
后仙峪硼矿区地表大多为混合花岗岩覆盖。从前人们认为该岩石为岩浆岩,其下不可能存在硼矿床。通过近年对该岩石的研究分析,以及野外工作我门认为该岩石为正常地层,并经钻探验证在该岩层下发现了隐伏硼矿体。 相似文献
72.
Steel production is an energy- and water-intensive process: large quantities of water are used for cooling, process and environmental-technical
applications. In the mid-1990s, Arcelor Gent, a large integrated carbon steel producing company in Flanders (Belgium), started
a number of water-related projects: the existing water infrastructure was adapted: the water from the coke plant was biologically
treated; canal water was demineralised using reverse osmosis; waste water from the blast furnaces was neutralised with alkaline
water from the steel plant. As a result of these projects, the quantity of discharged waste water was reduced by a factor
of 2 (water recycling doubled from a factor of 10 to a factor of 20), and the discharge of pollutants decreased. Also resource
consumption decreased: lime used in the steel plant, could be recovered to precipitate Zn in the waste water of the blast
furnaces.
Arcelor Gent obtained for these projects several Environmental Awards. 相似文献
73.
提出了一个新的矩形非协调混合元格式,把它应用于Stokes问题的数值逼近,得到了最优的误差估计. 相似文献
74.
75.
76.
采用83×2dtex(120N/2)绢丝纱和417dtex(24N/1)亚麻纱交织,生产国际市场流行的服装面料,分析总结了这一新产品的生产工艺与条件。 相似文献
77.
Oils in Jinghu sag are abundant with high content of polar compounds and have a low ratio of saturate to aromatic hydrocarbons and a high ratio of resin to asphaltene. The gross composition of oils in the Jinghu sag suggests typical immature to low mature characteristics. Some compounds with low thermal stability were identified. Light hydrocarbons, a carbon preference index, an odd even index, n-alkane and hopane maturity parameters show mature features and little differences in the maturity level among oils. Sterane isomerization parameters indicate an immature to low mature status of oil. Transfer of the sedimentary center during sedimentation has led to different thermal histories among subsags and thus generated oils with different maturities. On the basis of source analyses, four migration and accumulation patterns with different maturity can be classified. Combined with available information on mergers of source, reservoir and long distance oil lateral migration, mixing conditions were present in the Jinghu sag. Experimental results indicate that maturity variations are caused by mixtures of hydrocarbons with different maturity. 相似文献
78.
Monomer recycling for vulcanized silicone rubbers in the form of cyclosiloxane monomers. Role of acid buffers 总被引:3,自引:0,他引:3
The KOH-catalyzed depolymerization of vulcanized silicone rubbers to reproduce cyclosiloxane monomers was studied. First, the depolymerization was carried out in toluene with varying amounts of KOH to find that the yield of monomers first increased and then decreased with the increment of KOH, the highest yield was 65% at the molar ratio KOH/(Si–O) UNITS=0.08. At the molar ratio 0.13 in the absence of solvent, the monomers yield was 46%. However, when an acid buffer such as KH2PO4 and KCOOC6H4COOH was added after the KOH-catalyzed depolymerization was over, the product yield was increased remarkably to more than 80%. 相似文献
79.
Vacuum deposited MoO3-V2O5 films of different molar concentrations have been used for DC electrical conductivity studies at different temperatures.
The optical absorption spectra of MoO3-V2O5 films of different molar concentrations have been measured. From these measurements it is found that optical band gap and
activation energy vary with molar concentration of MoO3-V2O5 films. 相似文献
80.
在室内试验的基础上,对轻质混合土密度、抗压强度、压缩变形特性等进行了分析,结果表明:EPS颗粒含量变化对降低轻质混合土的密度作用效果显著;EPS颗粒含量对混合土抗压强度的影响很小,抗压强度主要取决于水泥的含量;在压缩变形特性方面,荷载小于混合土压缩屈服应力时EPS颗粒含量对混合土的压缩变形量影响较小。由此认为EPS颗粒在降低混合土密度方面具有一定的优越性,但对混合土的抗压强度、压缩变形量影响不明显,所以将混有EPS颗粒的轻质混合土作为填土材料具有很好的应用前景。 相似文献