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入世对专业图书馆影响的综合分析 总被引:2,自引:0,他引:2
加入WTO对专业图书馆的影响是多方面的、复杂的,这些影响包括思想观念、管理理念、上游市场环境、文献信息需求、行业优化等方面,具有冲击性、长期性、不均衡性等特点。面对这些影响和冲击,应从不同层次上采取相应的对策,宏观上完善立法、加大投入建立国家科技文献资源保障体系和推进改革;微观上专业图书馆要转变观念、改进管理、充分利用有限资源加强服务和拓展服务,或适时转向。 相似文献
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不考虑缓冲剂的加入,各种电解技术参数,例如Ni离子浓度、pH值和电解液温度的差异可以广泛地影响纯硫酸体系中电积镍的物理外观和电流效率。质量好的电积镍板应该平整、光滑和具有很好的延展性,质量差的板面多为爆皮、卷曲、多氢气孔和有脆性。以上这些都是由三个影响因素的选择所决定的。良好的物理外观质量和高电流效率取决于较高Ni浓度和合适的电解液温度,在较低的pH值的情况下,电积镍的物理外观质量得到改善,但同时会使电解沉积的电流效率降低。沉积的晶核位向已确定,但没有特殊的趋向性。循环伏安法显示出物理外观和这些影响因素有一定关系,但是电流效率和它们没有直接关系。 相似文献
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轴承部件处于机械设备的连接轴位置,故受到反复应力,因此在使用一定时间之后,可能产生疲劳裂纹。为了保证其与机械设备的使用寿命同步,必须提高轴承钢的质量。影响轴承钢寿命的因素是:非金属夹杂和偏析等。在这些因素中,已经用各种方法对非金属夹杂的影响进行了研究。根据这些研究可知, 相似文献
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研究了毛坯管密度、旋压温度、加工率和进给量等因素对无缝铱管旋压加工的影响。结果表明,合理控制这些因素是节约原材料,提高成品率的关键。 相似文献
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鉴于奥氏体-铁素体双相不锈钢所固有的抗应力腐蚀开裂能力,其应用环境常常具有强腐蚀性,这就有必要提高钢中的铬、钼含量。然而,合金含量的提高导致了在高温受热后对σ相和其他有害金属间相敏感性的增加。因为这些相可以显著降低耐蚀性、韧性、塑性和疲劳性能,所以发展了相应的敏感性检验和性能试验,用于鉴定这些相及其影响。 相似文献
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在钢中对氮的控制是很重要的,因为氮有很多害处,在某些场合氮对物理性能和表面质量具有有利之处。把Ti加入钢水中会对钢中的氮起稳定作用,这已是很普通的事。钛与氮、碳、氧反应形成氮化钛、碳化物、碳氮化合物和氧化物。这些夹杂物可能对韧性、延展性及焊接性能有影响,这些夹杂物可凝聚在一起引起表面质量问题。 相似文献
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磨矿过程对硫化矿矿浆电位的影响 总被引:4,自引:0,他引:4
本文以凡口铅锌矿矿石和赤马山铜矿矿石为对象,研究了磨矿过程对硫化矿矿浆电位的影响规律。在试验中进行了钢球磨与瓷球磨的磨矿对比,探讨了铁质的影响。并深入研究了磨矿细度、磨矿浓度和一些药剂对矿浆电位的影响规律。提出在选择粉碎方式、设备类型、介质品种时,应充分注意这些影响,才能保证获得最佳选矿指标。 相似文献
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成泉辉 《稀有金属与硬质合金》2004,32(3):49-52
分析了高氟铍矿中的氟在工业氧化铍冶炼中的行为和影响,提出了减少和消除这些不利影响的措施,以降低工业氧化铍冶炼成本,提高金属回收率.减少环境污染。 相似文献
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高扬学生的主体性培养具有主体精神的人才安贤林社会主义市场经济理论的提出,给教育带来了重大的影响。这种影响触及到了有关教育的性质、功能,教育的体制和运行机制,宏观和微观的教育改革等一系列带有根本性的问题。对这些问题进行深入的理论和实践研究,是当前理论工... 相似文献
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邯钢烧结原料结构的优化研究 总被引:1,自引:0,他引:1
通过对邯钢烧结用含铁原料的单烧值和冶金价值的计算。评价了各种含铁原料的经济价值。并以此对含铁原料进行筛选。达到了优化原料结构的目的。若进一步配合烧结配矿试验则可以找出不同条件下的最佳配比。 相似文献
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In accordance with the national energy strategy, the development of coal-fired power stations in Russia, especially in Siberia and the Far East, calls for utilization of their ash and slag wastes. The total quantity of ash and slag in Russian tailings exceeds 1.5 billion t. These wastes cover an area of more than 220 km2. The utilization of these wastes is no more than 10%. The most promising approaches are utilization of the wastes in construction materials or road building, or a hybrid approach in which valuable metals are extracted during the production of construction materials. Some fly ash can be used in agriculture. The physicochemical properties of ash and slag waste and correspondingly their applicability and the choice of technology will be determined by the mineral component of the coal and the methods by which the coal is burned. In order to use fly ash in construction, dry processing methods for ash and slag waste must be introduced. On the one hand, that involves greater capital expenditures on equipment and structures for storage, classification, crushing, and grinding of the ash and slag waste, as well as means of modifying their properties. On the other, increased transportation and organizational barriers must be expected. Examples of proposed processing technologies based on metal extraction and the production of construction materials are presented. To obtain iron-bearing concentrates, single-stage magnetic separation is mainly employed. However, the resulting quality of the concentrate is unsatisfactory. A better approach to the extraction of metals from ash and slag waste is flotation. At the same time, the available data indicate that the application of flotation may be limited by economic and organizational factors and associated environmental hazards. The conclusion is that the use of such technologies at thermal power stations that are already in operation is possible, with state support. 相似文献
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S. N. Kuznetsov E. V. Protopopov S. V. Feiler M. V. Temlyantsev 《Steel in Translation》2017,47(6):359-362
Steel-smelting slags form a large proportion of metallurgical wastes. They are generated at a rate of 150–200 kg/t of steel, on average. At current rates of steel production in Russia, the annual output of smelting slag is 9 million t, of which 8–11% consists of metallic iron and 15–40% of iron oxides. The total iron content in the slag is 20–30 wt %. Steel-smelting slag represents a valuable source of iron, which should be processed and returned to production. The slag-processing system at AO EVRAZ ZSMK permits stepwise removal of iron-bearing inclusions from the slag by magnetic separation. The iron-bearing concentrate obtained consists of three fractions: 0–10 mm (for use in sinter production); 10–80 mm (for blast-furnace use); and 80–250 mm (for use in steel smelting). The use of the 0–10 and 10–80 mm fractions in steel production in 160-t converters is considered in the present work. A mathematical model permits multivariant calculations to investigate the smelting dynamics and the distribution of added iron-bearing concentrates in the metallic melt, for different trajectories and dosing protocols. Analysis of the results yields new information regarding the hydrodynamic processes when iron-bearing concentrates from the slag-processing system at AO EVRAZ ZSMK are injected in the converter bath. 相似文献
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在阐述钢渣的分类、钢渣的性质、钢渣处理工艺的基础上,指出钢渣在厂内循环利用时可用做冶金原料、烧结熔剂、炼钢熔剂,并提出了实现钢渣利用的途径和钢渣返回利用应注意的问题。 相似文献
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The company Mittal Stil Temirtau has accumulated more than 13 million tons of steelmaking slag, and it annually adds another
600,000 tons of slag to this amount from ongoing production operations. Here, some of the iron from the production process
is lost in the form of metallic iron and oxides. The total amount of iron lost is estimated to be 15%. Studies have established
that discarded steelmaking slags contain up to 8% magnetic products. A slag-processing unit began operation at the dump in
2003 to recover scrap from the slag. The unit has a productivity of 120 tons of bank slag per hour and can process slag with
an initial coarseness of up to 700 mm. Extracting iron-bearing products from steelmaking slags and returning them to the production
cycle has reduced iron losses by 30% for the metallurgical conversion as a whole.
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Translated from Metallurg, No. 1, pp. 80–81, January, 2006. 相似文献
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工业废弃渣系指平炉钢渣,平炉沉渣及均热炉渣等,它们含有较高的金属铁和铁的氧化物,用于烧结生产后,可使其得到回收利用,通过烧结试验和生产实践,研究了工业废弃渣用于烧结生产的可行性和经济性。 相似文献
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