Sulfide assemblages in granulite xenoliths from Hannuoba Basalt, Hebei Province, China

Granulite xenoliths are important samples for understanding the forming and evolution of the crust. The granulite xenoliths enclosed in Cenozoic basalt of Hannuoba, Hebei Province, China, contain four types of sulfide assemblages: isolate rotundity enclosed sulfides, intergranular sulfides between minerals, secondary sulfide inclusions ranging in linear, and fissure-filling sulfides.Electron microprobe analysis shows that the components of sulfides are Ni-poor pyrrhotite with the molar ratios of (Ni Co Cu)/Fe less than 0.2. The molar ratios of (Fe Cu Co Ni)/S are less than 0.875 of normal pyrrhotite, and are less than those of mantle xenoliths, reflecting a sulfur-saturated environment. Pyrrhotite in various occurrences contains some Au and Ag, with the averages of 0.19wt%-0.22wt% Au and 0.01wt%-0.02wt% Ag, showing the gold mineralization related to the granulitization of low crust. Ni, Co and Cu have a normal correlation with S in pyrrhotite, indicating that heavy metal elements have a same source similar to sulfur because of the degasification of upper mantle.     

Synthesis of mesoporous carbon as electrode material for supercapacitor by modified template method

The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capacitance of the mesoporous carbons increase with the increase of mass ratio of silica sol to carbon source （glucose）. A modified template method, combining silica sol template method and ZnCl2 chemical activation method, was proposed to improve the mass specific capacitance of the mesoporous carbon with an improved BET surface area. The correlation of rate capability and pore structure was studied by constant current discharge and electrochemical impedance spectroscopy. A commercially available microporous carbon was used for comparison. The result shows that mesoporous carbon with a larger pore size displays a higher rate capability. Mesoporous carbon synthesized by modified template method has both high mass specific capacitance and good rate capability.     

Surface oxidation behavior of Mg-Y-Ce alloys at high temperature

After the Mg-Y-Ce magnesium alloy was exposed to air at a temperature up to 1173 K for 0.5 hours, the dense and compact oxide film formed on the surface. Accordingly, oxidation and ignition of magnesium alloys at elevated temperature was successfully retarded by the Y and Ce additions. Thermogravimetric measurements in air revealed that the oxidation dynamics curves measured at 673 and 773 K followed the parabolic-line law and the curve investigated at 873 K followed the complicate quartic law. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis indicated that the oxide film on the surface of Mg-Y-Ce alloys exhibited a duplex structure, which agreed with the results of thermodynamic analysis. The oxidation film included two layers: the outer layer was a multiple structure of Ce_0.202Y_0.798O_1.601 and Y₂O₃, and the inner layer mainly consisted of metal Mg and MgO.     

Characterization of (Y,Gd) BxV1-xO4-x:Eu Phosphor Prepared by Coprecipitation Reaction

White body-color (Y, Gd)BxV1- xO4-x :Eu3 phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd)BxV1- xO4-x :Eu3 phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu3 . But its relative emission intensity is only about 90% of the commercial phosphor.     

A new method for recovering valuable metals from low-grade nickeliferous oxide ores

A new method, the concentrated sulfuric acid acidolysis and water leaching (SAWL) of nickeliferous oxide ores, is proposed and the optimal conditions for recovery of nickel, cobalt and copper from a low-grade Chinese nickeliferous oxide ore are presented. A series of experiments were conducted which examined the effect of acid charge, acid curing temperature and acid curing time. Recoveries of up to 95%, 83% and 95% for Ni, Cu and Co, respectively were obtained with only the sulfuric acid at ambient temperature and atmospheric pressure. Comparing the percolation leaching with agitation leaching showed that percolation leaching was capable of extracting the valuable metals with water. The SAWL method was scaled to three-stages counter-current leaching tests using 1 kg of ore. The results indicate greater than 90% extraction for nickel and cobalt.     

La1-xCaxMnO3纳米单晶丝的制备及磁热效应研究

采用化学共沉淀法和热处理的方法制备了La1-xCaxMnO3(x=0.3,0.4,0.5)系钙钛矿型氧化物(LCMO),经XRD确定样品为钙钛矿型结构。TEM分析表明样品直径约为40nm的枝节状纳米丝,用△Tad-T测量仪测量了△Tad-T。与块状样品相比居里温度的波峰变宽,绝热磁温变降低。     

八钢电炉炼钢生产组织模式优化实践

八钢电炉炼钢厂在实际生产中长时间处于全废钢冶炼条件,由于电炉全废钢冶炼周期延长,导致精炼和连铸工序作业率严重不足,能耗增加,指标下降。针对以上问题对电炉的生产工序进行了优化,并最终实现了和生产现场的有机结合,对电炉在全废钢的工艺条件下组织生产具有积极有效的指导作用。     

安钢7^#380m^3高炉无料钟炉顶布料规律研究

无料钟炉顶是现代高炉的代表形式。针对安钢炼铁厂7#380m3 高炉布料系统开展研究工作,利用高炉布料理论完善布料工艺。通过研究高炉的布料规律,利用理论联系实际的方法,建立一套用于指导生产的相关布料方程,为实现高质量的布料提供理论依据。     

低温沉积陶瓷涂层技术的研究进展

对当前低温沉积陶瓷涂层的技术进行了综述,包括液相沉积法、溶胶-凝胶法等,并分析了各种低温沉积技术的优缺点,展望了低温沉积技术的发展前景.     

住宅小区智能化系统工程初探

文章对住宅小区智能化的概念和功能进行了详细介绍,重点阐述了计算机、通信与网络、自控、IC卡技术在以住宅小区为代表的数字化人居环境发展中的作用与意义,并针对建设与管理存在的问题提出了合理化建议。