降低高炉燃料比的措施及效果

针对原料不稳定、高炉喷煤量低、热风炉风温低且不稳定现象,通过加强槽下筛分管理,恢复热风炉助燃空气和煤气的双预热,对炉前输煤管路、喷枪装置进行改造,采用焦丁混装技术等措施,安钢永通2号高炉燃料比由535 kg/t Fe降到了527 kg/t Fe,实现了高炉低成本运行。     

全钒氧化还原液流电池电解液的研究

研究在40℃温度下,添加剂对全钒氧化还原液流电池电解液稳定性的影响.通过采用硫酸亚铁铵溶液对钒电池电解液进行电位滴定,定量分析钒电池电解液中不同价态钒离子的浓度;利用循环伏安曲线扫描,分析添加剂的引入对电解液电化学性能的影响.结果表明:温度40℃时,添加剂对五价钒溶液稳定性的影响次序为:尿素>硫酸钾>CTAB>草酸铵>草酸钠;添加剂对钒溶液氧化活性的影响为:草酸钠>尿素>硫酸钾>CTAB>草酸铵;对还原活性的影响为:草酸铵>草酸钠>硫酸钾>CTAB>尿素;对氧化还原反应可逆性的影响为:尿素>草酸钠>硫酸钾>CTAB>草酸铵.     

CaCl2熔盐中自烧结电解制备粉体Cr3C2及其机制

以氧化铬和石墨粉为原料,采用聚乙烯醇粘接,压制成阴极片,以光谱石墨棒为阳极,在800℃氯化钙熔盐中,恒电压3.2V下,阴极片自烧结电解制备碳化铬.采用XRD、SEM和EDX对样品进行表征.结果表明:粘接的阴极片满足熔盐电解的强度要求,通过熔盐电解过程的自烧结阴极片有效地粘接在一起,并制备出具有良好烧结性能、组分单一的Cr3C2粉体.该法制备Cr3C2的电流效率不低于37.3％.采用恒电位电解法和循环伏安法对电解机制的研究表明,熔盐电解制备Cr3C2的反应机制为:Cr2O3+e→Cr+O2-,Cr+C→Cr3C2两步完成.     

浅析原子荧光法测定水中汞

介绍了用原子荧光光度计测定水中汞的方法。对检测结果进行分析,发现相较于双硫腙分光光度法和冷原子吸收法测定汞,荧光法有快速、简便、灵敏度高、干扰少、线性范围宽、检测限低等优点。     

Electromagnetic analysis of ITER diagnostic equatorial port plugs during plasma disruptions

ITER diagnostic port plugs perform many functions including structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to the plasma. The design of diagnostic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate responses of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the diagnostic first walls (DFWs), diagnostic shield modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed.     

液压支架矸石充填捣实机构的结构分析

矸石充填是当前煤矿生产中常用的一种充填方式,用于液压支架后部的矸石捣实机构是充填工作的关键设备。矸石捣实机构有单级捣实机构和双级捣实机构,其支撑方式有下部推拉及上部吊挂等多种形式。根据现场使用经验,对结构进行了分析,并对充填开采方法提出一点建议。     

Formation of TiC hexagonal platelets and their growth mechanism

A large amount of TiC hexagonal platelets has formed on the surface of the sample made of Ti/Si/TiC/Al_0.2 after sintering at above 1450 °C in an Ar atmosphere. The basal plane of TiC platelets is (111) facet confirmed by X-ray diffraction. Small amounts of Si and Al elements dissolved in the TiC crystal structure, influencing the structure of TiC. The detailed structure and growth mechanism of the TiC platelets have been observed and analyzed. A model has been proposed to understand the formation of TiC hexagonal platelets.     

Novel methods for synthesis of high‐impact polystyrene with bimodal distribution of rubber particle size

By using in situ prepolymerization and radiation curing, high‐impact polystyrene (HIPS) with a bimodal distribution of the size of the rubber particles (bimodal HIPS) was synthesized in the presence of ultrafine full‐vulcanized powdered styrene–butadiene rubber (UFPSBR) and polybutadiene rubber (BR). TEM photographs indicated that UFPSBR was dispersed uniformly as a single particle with a diameter of about 100 nm. On the other hand, bimodal HIPS with different rubber particle size distributions could also be obtained by blending HIPS and UFPSBR grafting styrene (UFPSBR‐g‐St) with different grafting yields. The bimodal HIPS with the smallest rubber particle size, at about 100 nm, could be prepared by blending the monomodal HIPS containing big rubber particles with polystyrene/UFPSBR. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Comparative study of three lignin fractions isolated from mild ball‐milled Tamarix austromogoliac and Caragana sepium

Six lignin fractions from mild ball‐milled Tamarix austromogoliac (TA) and Caragana sepium (CS) were sequentially isolated with 80% dioxane containing 0.05M HCl at 75°C for 4 h, 50% aqueous ethanol containing 1M triethylamine at 70°C for 4 h, and 8% aqueous NaOH at 45°C for 3 h. The results showed that the successive treatments made it possible to isolate lignin from wood with a high yield and purity, in which 89.4 and 90.6% of the original lignin from TA and CS were released, respectively. The lignin fractions isolated with the three‐step method were analyzed with Fourier transform infrared, ¹H‐ and ¹³C‐NMR, alkaline nitrobenzene oxidation, and gel permeation chromatography. It was found that the three lignin fractions isolated from TA were rich in syringyl units, and the molar ratio of the relatively total moles of vanillin, vanillic acid, and acetovanillin to the relatively total moles of syringaldehyde, syringic acid, and acetosyringone decreased from 1: 2.6 to 1 : 3.2 to 1: 3.6 in the lignin preparations, whereas this ratio in the corresponding lignin fractions isolated from CS was found to be 1.4 : 1, 1.1 : 1, and 1 : 1.4, respectively. More importantly, the results revealed that the sequential extractions of the mild ball‐milled TA and CS with 80% acidic dioxane, 50% alkaline ethanol, and 8% aqueous NaOH under the conditions used did not significantly cleave the β–O‐4 and α–O‐4 linkages in lignin macromolecules. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

彩涂卷钢涂层厚度对耐老化性能的影响

分析了目前国内外彩涂卷钢市场需求的现状,通过紫外人工加速老化试验,从涂层表面光泽保持率、色差以及表面粉化、开裂的角度,着重研究了彩板的不同面漆涂层厚度对彩板耐老化等相关性能的影响.用减薄涂层来降低彩板生产成本的方法,必然带来严重的质昔问题.