20号钢圆坯生产过程中水口侵蚀研究

针对20号钢圆坯生产过程中侵蚀水口严重,导致生产成本增加的问题,根据20号钢侵蚀水口的机理,研究了20号钢的脱氧强度对水口侵蚀程度的影响,以及保护渣性能对侵蚀水口的影响。通过调整钢水氧化性和保护渣关键性能,改善了20号钢圆坯生产过程中发生的侵蚀水口严重的问题,延长了连浇炉数,降低了生产成本。     

铸钢用滑动水口砖

滑动水口砖是近年来发展的新产品。用它代替塞棒铸钢是铸钢工艺的重大技术革新,不仅改善了铸钢工人的劳动条件,杜绝了断棒漏钢重大事故,而且提高了钢厂生产力,降低了耐火材料消耗,减少了钢中非金属夹杂,提高了钢的内在质量。鞍钢耐火厂从1972年开始研制滑动水口砖,1976年鉴定并投产了高铝质、镁铝质、铝铬质滑动水口砖,经鞍钢三大钢厂使用,效果良好。为适应不同冶炼方法、不同钢种、不同浇铸工艺的需要,1978年试制成功了不烧高铝石墨质、镁铝石墨质滑动水口砖,取代铝铬质、镁铝质滑动水口砖。在鞍钢两大钢厂100t 和     

延长钢包寿命降低耐火材料成本的措施

(1)水口砖的改善原设置400ｍｍ见方两种水口:一是吹气用多孔塞(即ＢＢ水口);二是浇钢水口(即ＳＮ水口)。改进措施:一是将方形砖改成圆形砖;二是将成砖工艺改为真空振动浇注成形;三是适当调整了耐火材料组分,即将原来的两种水口及不同材质调整为一种(铝镁质)材质,具体成分为91%Ａｌ2Ｏ3、0.5%ＳｉＯ2、8%ＭｇＯ,各种物性指标也相应改善。使用结果表明,改进后砖不易产生裂纹,且致密性能、耐氧气清洗性能优良。(2)钢包内衬结构的改善内衬渣线部比接触钢液部更易熔损,故选用了进口镁铬质砖砌筑渣线。进口砖的化学组成为69.7%ＭｇＯ、12.4%Ｃｒ2…     

提高钢包水口自动开浇率的研究

为了解决钢包水口自动开浇率低且影响连铸机连浇的问题,莱钢炼钢厂对引流砂进行了研究,改进了座砖与上水口。使用试验证明,钢包水口自动开浇率达到92%以上,综合包龄提高至95.9炉次,为实现无氧化浇注、开发洁净钢奠定了基础。     

连铸用的铝碳质和铝锆碳质长水口砖

连铸用的铝碳质和铝锆碳质长水口砖为实现连铸钢水罐和中间罐之间的钢水流股的密封浇铸，国外一些耐火材料生产厂家开发成功了连铸用的铝碳质和铝锆碳质的长水口砖．连铸中间罐用的长水口用高纯度原料制成并用等静压机成型．长水口砖经高温隧道窑烧成后，要在车床上加工到...     

从钙处理到凝固钢中夹杂物改性及析出热力学研究

钙处理是使钢中氧化物和硫化物夹杂转化成对钢的性能有利的无害夹杂很好的方法。通过钙使固体AlO2半状物转化成液体铝酸钙，从而避免铝脱氧钢连铸期间水口堵塞。钙处理也是改进钢的机械加工性的一种重要方法，增加硫含量可进一步改进机械加工性。然而，加硫钢由于缺乏氧化物的改性以及形成容易堵塞水口的固体硫化钙而出现学浇注问题。     

铝锆碳浸入式水口异常堵塞原因分析

对钢液微合金化钛处理后引起堵塞的铝锆碳质浸入式水口进行分析,结果表明:堵塞物质为铝酸钙和钙钛矿。铝酸钙有变质体中的析出相,也有水口内壁处的原位反应产物,还有钢液中内生夹杂物。中包渣渗有钛处理和铝处理后的残留物,改变了原有属性,导致水口边滞留,为新生高熔点物质铝酸钙提供了物质来源,新生和内生铝酸钙及钙钛矿共同引起水口结瘤导致堵塞。     

从钙处理到凝固钢中夹杂物改性及析出热力学研究

钙处理是使钢中氧化物和硫化物夹杂转化成对钢的性能有利的无害夹杂很好的方法。通过钙使固体Al2O3串状物转化成液体铝酸钙，从而避免铝脱氧钢连铸期间水口堵塞。钙处理也是改进钢的机械加工性的一种重要方法，增加硫含量可进一步改进机械加工性。然而，加硫钢由于缺乏氧化物的改性以及形成容易堵塞水口的固体硫化钙而出现浇注问题。[第一段]     

改善连铸水口用MgO-C材料耐熔损性

常用的Ａｌ２Ｏ３Ｃ（即ＡＧ）质水口在浇铸ＣａＳｉ处理钢时,因钢液中的ＣａＯ与水口材料中Ａｌ２Ｏ３生成低熔点产物而增大了水口的熔质。在接合部采用ＭｇＯＣ（即ＭＧ）质内插式水口的试验表明,当连铸ＣａＳｉ处理钢时,随着水口工作面石墨的氧化消失,伴有渣及钢液的浸润,连铸一般钢时,碳的氧化消失则导致水口材料耐蚀性下降。在多种相关试验研究基础上,向ＭＧ耐材中加入金属系防氧化剂并减少其含碳量,可提高耐氧化性和耐蚀性,但耐崩裂性变差。因此,应根据使用条件确保材料的耐熔损性及耐崩裂性间的平衡。改善连铸水口…     

钢包引流砂机械式投放技术的开发应用

针对莱芜钢铁集团有限公司银山型钢有限公司炼钢厂采用人工投放钢包引流砂,导致引流砂大量浪费,增加钢水夹杂,影响水口自开率,制约炼钢生产等问题,通过开发引流砂复合引流器投放工艺技术以及对钢包水口座砖内径进行调整优化等措施,实现了钢包引流砂机械式投放。使水口自开率由95.5%提高到99.2%,吨钢引流砂消耗降低了0.37 kg。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.