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71.
应用电沉积技术制备了Fe-P合金电极材料。采用X射线衍射(XRD)和扫描电子显微镜(SEM)分析了该合金材料的相结构和表面形貌。XRD分析结果表明电沉积的Fe-P合金具有非晶态结构。电化学性能测试表明:平面结构的Fe-P合金电极首次放电(脱锂)容量达542 mAh·g-1,首次循环的库仑效率为60%;50周循环之后放电容量为366 mAh·g-1。用非原位的XRD和SEM对电极的充放电机理进行了初步研究,结果表明,首次充电(嵌锂)过程中形成Li3P相,电极表面生成纳米棒结构铁-磷合金,它能有效缓解锂嵌入/脱出时引起的合金结构变化,抑制合金材料的体积膨胀,从而提高该合金电极的充放电效率和循环性能。  相似文献   
72.
In this paper, we study the heat transfer in the fully developed flow of a viscoelastic fluid, a slag layer, down a vertical wall. A new constitutive relation for the stress tensor of this fluid is proposed, where the viscosity depends on the volume fraction, temperature, and shear rate. For the heat flux vector, we assume the Fourier's law of conduction with a constant thermal conductivity. The model is also capable of exhibiting normal stress effects. The governing equations are non‐dimensionalized and numerically solved to study the effects of various dimensionless parameters on the velocity, temperature, and volume fraction. The effect of the exponent in the Reynolds viscosity model is also discussed. The different cases of shear‐thinning and shear‐thickening, cooling and heating, are compared and discussed. The results indicate that the viscous dissipation and radiation (at the free surface) cause the temperature to be higher inside the flow domain. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
73.
介绍了主要炉渣成份对炉渣流动性能影响的实验研究,利用minitab分析了碱度、MgO以及Al_2O_3对炉渣熔化性温度、粘度与热稳定性的影响程度,并用方差分析找到了Al_O_3对炉渣流动性能影响的拐点,为高炉生产提供指导,并对今后大高炉的优化配矿提供技术支撑。  相似文献   
74.
The Vredefort Impact Structure in South Africa is the biggest and oldest remnant meteorite impact crater in the world where various ancient cultures thrived. In this paper some light will be shed on the Iron Age, iron smelting aspects of the people that inhabited the area and the results of a laboratory study of iron artefacts and a possible source of iron ore in the region is given. A sectional piece from a hoe manufactured in a small bloomery furnace was polished and etched and subsequently analyses with SEM and Mössbauer techniques were obtained. The hoe has a typical cast iron composition (2.9% C, 0.1% Mn, 0.4% Si, 0.4% P and 96.2% Fe, all wt.%) and contains many slag inclusions with wustite dendrites. The Mössbauer spectrum consisted of iron (86%), wustite (5%) and oxihydroxide (9%) and the thin (200 μm) corrosion layer consisted of hematite (55%) and oxihydroxides (45%). At a furnace site, various slag clumps (26.3% C, 24.8% SiO2, 11.3% Al2O3, 1.3% P2O5, 1.0% K2O, 0.4% CaO and 30.2 FeO, all wt.%, average of four samples) and iron nodules (7.6% C, 6.0% Mn, 4.3% Si, 1.4% Al, 80.7% Fe, all wt.%) were found. The Mössbauer spectrum of the slag consisted of iron (7%), magnetite (56%), fayalite (2%) and oxihydroxides (35%) and that of the iron nodules yielded iron (28%), wustite (12%), magnetite (20%) and oxihydroxides (40%). A possible ore source containing 84% FeO, 7% of Al2O3 and SiO2 (all in wt.%) and minor impurities is located a few kilometers from the furnace site, yielding a Mössbauer spectrum consisting of hematite (70%) and oxihydroxides (30%).  相似文献   
75.
Radiation shielding effects of ferrochromium slag loading hardened epoxy resin samples were investigated. Five different samples including different percentages of epoxy resin and ferrochromium slag were produced. X-ray, gamma ray, and neutron particle transmission experiments were performed for epoxy-ferrochromium slag composites. Also, FLUKA Monte Carlo simulations were made to obtain absorbed doses. As a result, radiation shielding performance increases with increasing ferrochromium slag additive in epoxy.  相似文献   
76.
77.
本文以工程实践,论述了电厂废料粉煤灰渣这种特殊类土的形成,物理力学特征,以及应用其修建我国最高的灰坝的经验。这个灰坝经过三年的安全贮灰运行验证,证明是成功的,创造了应用电厂粉煤灰渣修建国内最高灰坝,并安全贮灰的新纪录。  相似文献   
78.
建立了测定预熔型精炼渣中氧化镁的火焰原子吸收光谱法。样品采用氢氟酸–王水–高氯酸分解后,加入少量硫酸可使溶液底部的絮状不溶物溶解完全。在盐酸介质中,加入氯化锶消除干扰,利用空气–乙炔火焰以原子吸收光谱仪进行测定。测定结果的相对标准偏差为0.50%~1.08%(n=12),测定标准物质的相对误差为–0.92%,加标回收率为97.56%~102.14%。该法操作简便,分析速度快,适用于大批量样品分析。  相似文献   
79.
采用碳酸盐法测定钢渣中活性氧化镁含量。研究了碳酸盐法测定钢渣中活性氧化镁反应的可行性和测定的准确性。结果表明:二氧化碳在水中可以将氧化镁和氢氧化镁转化成可溶性镁离子,然后用EDTA标准溶液滴定其含量,氧化镁、氢氧化镁与二氧化碳的反应率均达到97%以上;二氧化碳与钢渣反应时间应大于105min,新余热焖钢渣中活性氧化镁质量分数为1.44%;压蒸后钢渣中氢氧化镁质量分数为1.86%,与原钢渣中活性氧化镁测定结果保持一致,相对误差小于1%。  相似文献   
80.
The influences of microwave heating on the phase transformation of titania slag were systematically investigated. The thermal stability, surface chemical functional groups and microstructure of the titania slag before and after microwave heating, at a temperature of 950?°C for 60 min, were also analyzed using thermogravimetry and differential thermal analysis (TG-DSC), Fourier transform infrared spectroscopy (FT-IR) spectrum and scanning electron microscope (SEM), respectively. The TG-DSC analysis revealed that the phase transformation of the titania slag from anatase TiO2 to rutile TiO2 occurred between 750 and 1000 °C. The FT-IR rustles demonstrate that the banding form of Ti4+, Ti3+ and Ti2+ ions and the methyl groups on the surface of the titania slag has changed and a new chemical bond Ti–OH was formed. The results of SEM showed that a large number of regulation rutile TiO2 crystals were found on the surface of the microwave-treated samples and the synthetic rutile has been synthesized successfully using microwave heating.  相似文献   
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