钢铁企业原材料采购决策探讨

2011年以后,钢铁的价格不断降低,使得钢铁行业不能够盈利或者盈利太低,当然这其中也有成本侵蚀和银行涨息的因素。随着信贷危机的不断发生,银行对于钢铁行业不再信任,甚至翻脸不认人,使得钢铁行业贷款的难度系数不断增加,所需要的成本也不断增加。所以钢铁行业要想继续赢得利润抵御风险、提高生存能力,运用科学合理的方法降低钢铁原材料的成本就显得尤为重要,这就必须对原材料的采购过程进行科学决策,以降低原材料成本,进而提高钢铁企业的盈利和生产能力。     

高分辨率铁尾矿遥感光谱特征分析与信息提取

遥感监测尾矿是矿山调查和监管的科学方法,也是地理国情监测的基础内容。研究了铁尾矿遥感影像解译标志和光谱特征,建立铁尾矿遥感信息的提取技术流程。利用尾矿光谱特征与纹理结构的特点,构建了铁尾矿遥感增强处理的RTI数学模型。并以唐山地区的铁尾矿及固体废弃物作为研究区,分析了模型的影响因子和有效性。为尾矿资源的自动监测和目标提取提供了新的处理手段。     

汉代辽东犁和其作亩法

本文通过考察东北农业的实体，分析了它的力量源泉。根据《齐民要术》中登场的“辽东犁”，研究古代中国东北地区的耕作方式和作亩法，来看末冷地带东北农业的本质。东北地区的农耕是在农业的原始基础上吸收了游牧民的畜牧技术和中原度韩半岛的农业文化。这种特征在耕作方式上可见一斑，即使用了辽东犁的作亩法。     

火力发电厂机组启动阶段铁含量测定方法改进的探讨

由于机组启动时候对给水、凝结水的含铁量要求较高,只有其合格才允许进行机组启动操作的下一步操作,而目前常用的测定铁含量的方法耗时较多,在机组启动过程中很难适应机组启动要求。通过大量实验,对目前国标规定的实验方法进行了一些改进,可以快速测定含铁量,误差完全可以满足机组启动需求。     

The perils of personal capital in antebellum America: John Spotswood Wellford and Virginia's Catharine Furnace

The Fredericksburg Iron and Steel Manufacturing Company's ironmaking facility, Catharine Furnace, had the look of a prime mover in antebellum Virginia's industrial sector when it opened in 1838. Its manager and principal owner, John Spotswood Wellford, successfully tapped into his social capital to secure military ordnance contracts, but in the process the firm became utterly dependent upon his ability to secure this work through personal connections. By failing to expand the market for its pig iron and castings in local, regional, and national markets, the firm relied upon these ordnance contracts for shot and shell for its existence. When Wellford died in 1846, the Fredericksburg Iron and Steel Manufacturing Company collapsed. A few years later, Catharine Furnace stood cold and abandoned – a severe reminder of the limited prospects of Virginia's industrial economy and the perils of relying on an individual entrepreneur's personal capital during a critical period of American industrialisation.     

从近代汉阳铁厂的改制看企业的生存机制

中国近代标志性企业——"汉阳铁厂"的兴衰有多方面原因。耗资巨大、影响巨大、浪费巨大,同时由于管理的无知、官僚习气、政府机会主义等构成的环境都影响了这一民族企业的发展,最终造成了该企业的不断改制。探究其更深层次的原因,是国家的政治体制根本不适应较为现代化企业的生存和发展,即作为政府应该为民族企业的发展提供公共服务,而不是与其进行竞争并限制其发展。     

Automatic control system for uniformly paving iron ore pellets

In iron and steelmaking industry, iron ore pellet qualities are crucial to end-product properties, manufacturing costs and waste emissions. Uniform pellet pavements on the grate machine are a fundamental prerequisite to ensure even heat-transfer and pellet induration successively influences performance of the following metallurgical processes. This article presents an automatic control system for uniformly paving green pellets on the grate, via a mechanism mainly constituted of a mechanical linkage, a swinging belt, a conveyance belt and a grate. Mechanism analysis illustrates that uniform pellet pavements demand the frontend of the swinging belt oscillate at a constant angular velocity. Subsequently, kinetic models are formulated to relate oscillatory movements of the swinging belt’s frontend to rotations of a crank link driven by a motor. On basis of kinetic analysis of the pellet feeding mechanism, a cubic B-spline model is built for numerically computing discrete frequencies to be modulated during a motor rotation. Subsequently, the pellet feeding control system is presented in terms of compositional hardware and software components, and their functional relationships. Finally, pellet feeding experiments are carried out to demonstrate that the control system is effective, reliable and superior to conventional methods.     

石墨形态和数量对奥-贝球铁性能的影响

对于要求抗拉强度≥1200MPa;断后伸长率≥1%;吸收能量(无缺口试样)≥35J的奥-贝球铁,如果其球化率差于3级,球墨粗于6级且每平方毫米球墨少于180个,等温处理后的力学性能不易达到规范要求。     

钢锭模失效分析

为找出钢锭模的使用寿命低,多数钢锭模应用不久便发生裂纹而报废原因,本文随机统计分析了钢锭模实效的形态,采用宏观及金相分析方法,对各种实效的原因和机理进行了探讨。认为,对各种形状的小型钢锭模,采用片状石墨较为粗大的灰口铸铁,是其使用寿命低的主要原因。因此小型钢锭模的材质应选择球墨铸铁,并做相应的物理检验。     

火焰、石墨炉原子吸收法测定自来水中微量铁

用火焰原子吸收法和石墨炉原子吸收法对自来水中微量铁进行了比较测定,结果表明,两种方法测定铁的各项指标均在质量控制要求范围内,且各有优点。火焰原子吸收法线性范围宽,干扰少,操作简便,测定速度快;石墨炉原子吸收法取样少,灵敏度高,检出限低。