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1.
 炉渣离子与分子共存理论认为,CaO-SiO2-Al2O3-MgO-TiO2渣中结构单元或离子对的作用浓度能够像传统意义上的熔渣活度一样表征化学反应能力。通过建立1773K时高炉CaO-SiO2-Al2O3-MgO-TiO2渣中结构单元或离子对的作用浓度控制方程,运用Matlab进行求解,进而建立了该渣系计算渣铁间硫分配比的通用热力学模型。此外,该模型能够定量计算出CaO和MgO各自对渣铁间硫分配比的热力学贡献率。建立的模型的计算结果表明,当TiO2含量增加时渣铁间硫分配比及CaO的热力学贡献率逐渐降低,而MgO的贡献率逐渐上升。  相似文献   

2.
储莹  郭汉杰  全永志 《特殊钢》2014,35(6):20-23
基于离子与分子共存理论,通过计算钢包炉(LF)精炼渣结构单元的质量作用浓度,建立了一种计算57CaO-10SiO2-8MgO-25Al2O3四元渣系与钢液硫分配比的热力学模型,计算得出1630℃LF精炼结束时,该渣系的渣-钢间的硫分配比LS=1115。通过9炉210 t双孔底吹氩LF渣样检测结果表明,当减去因现场和渣系的氧势等条件限制,所存在的定值系统偏差,该模型可有效反映工业生产的LF精炼渣硫分配比。  相似文献   

3.
在富氧顶吹熔融还原冶炼高磷铁矿的工艺研究中,以共存理论为基础,结合全选主元松弛迭代法,利用VB 6.0计算了CaO-MgO-FeO-Al2O3-SiO2-P2O5渣系中结构单元或离子对的质量作用浓度,并建立了该渣系与碳饱和铁液间硫分配比的热力学模型,由该模型计算的硫分配比与工艺中实测的硫分配比吻合程度较好,说明利用共存理论所建立的脱硫模型能适用在熔融还原高效脱磷熔渣。  相似文献   

4.
选用文献报道的14个渣系铁氧化物活度aFetO作为基础实验数据,验证了基于炉渣离子-分子共存理论(IMCT)所定义的铁氧化物综合质量作用浓度NFetO表征炉渣氧化性的可能性和精度.为了得到14个渣系的NFetO,建立了CaO-SiO2-MgO-FeO-Fe2O3-MnO-Al2O3-P2O5渣系的IMCT-Ni模型,其他13个渣系NFetO可由该渣系的IMCT-Ni模型经简化得到.结果表明,铁氧化物综合质量作用浓度NFetO不仅可像活度aFetO一样表征炉渣氧化性,而且比实测aFetO精度更高.   相似文献   

5.
根据炉渣结构共存理论和相关相图,建立了MnO-FeO-SiO2-Al2O3渣系作用浓度的计算模型,考察了炉渣温度、FeO含量对锰在渣-钢间分配比(LMn)的影响.研究结果表明,模型计算的作用浓度值NMno、钢液中锰含量和LMn与文献中的实测值相吻合;LMn随着温度的升高而降低,随着渣系中FeO含量的增加而增加.因此,本...  相似文献   

6.
根据炉渣结构的共存理论,推导了CaO-Al_2O_3-SiO_2熔渣的作用浓度计算模型。模型计算得出的各组元的作用浓度值与文献报道的活度值非常一致。在此基础上,进一步采用回归分析法找出了CaO-Al_2O_3-SiO2渣系中溶解的氮含量以及与此渣系相平衡的钢中氮含量及氮的分配比随渣中各组元作用浓度之间变化的定量关系,理论计算结果与实验值非常符合。  相似文献   

7.
 为了精确表征含Na2O渣系的脱硫能力,改善脱硫效果,基于熔渣离子与分子共存理论(IMCT)建立了CaO-SiO2-MgO-Al2O3-Na2O渣系结构单元的作用浓度计算模型和1 753 K时该渣系的脱硫热力学模型。并对渣系的总硫分配比及各自硫分配比的影响因素进行了讨论分析。理论结果表明,除LS, MgS外,随着Al2O3质量分数的增加,该渣系的脱硫能力明显下降,而MgO和Na2O质量分数的增加,对提高渣系的脱硫能力具有明显的促进作用。此外,少量的Na2O即可表现出很强的脱硫效果,这为含有Na2O的冶金二次资源在铁水脱硫过程中的应用以及铁水脱硫渣系的优化提供了必要的理论依据。  相似文献   

8.
 为了研究Inconel718高温合金电渣重熔过程中渣系各组元对合金中易氧化元素铝、钛的影响,以五元渣系CaF2-CaO-Al2O3-MgO-TiO2为基,通过分子与离子共存理论,根据渣金界面中各组元的平衡反应和物质守恒,建立了Inconel718高温合金电渣重熔过程中渣金界面铝、钛元素氧化反应的热力学模型。通过分析该模型并对模型结果进行渣金平衡验证试验,验证了模型的有效性。研究结果表明,渣中CaF2、MgO质量分数的变化对合金中铝、钛元素的影响很小;渣中Al2O3有烧钛增铝的作用,TiO2有烧铝增钛的作用,CaO能够抑制铝元素的烧损;能够有效减少Inconel718高温合金电渣重熔过程中铝、钛元素烧损的渣系配比为CaO质量分数为20%~25%、TiO2质量分数为4%~6%、MgO质量分数为1%~4%、CaF2质量分数为50%~60%、Al2O3质量分数为15%~20%。  相似文献   

9.
建立了不锈钢渣的CaO-MgO-FeO-SiO2-Al2O3-Cr2O3六元渣系活度模型.基于共存理论的活度模型得出了渣系中主要组分及复合氧化物在不同条件下的活度.结果表明,原渣系中的Cr2O3主要形成了不稳定的CaCr2O4,在自然环境中可以被氧化为酸溶性的CaCrO4,从而释放出强毒性的Cr6+,因此不锈钢渣具有潜在毒性.温度、碱度以及渣中MgO、FeO都对Cr2O3进入尖晶石相中从而实现稳定解毒有影响.通过调节渣系成分和处理条件能够基本实现含铬废渣的无公害化.  相似文献   

10.
 针对高炉初渣、中间渣组分多变特别是FeO含量高等问题,系统研究了CaO-SiO2-Al2O3-FeO-MgO五元渣系的黏度及组分对黏度的影响规律,并建立了基于WEB的神经网络-遗传算法(ANN-GA)系统的高炉渣黏度预报模型。结果表明,该模型对高FeO渣系的黏度预报值与试验结果吻合较好,误差在20%以内。通过模型预报获得的各因素对渣黏度影响的规律与文献及试验结果一致。  相似文献   

11.
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)  相似文献   

12.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

13.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

14.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

15.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
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。  相似文献   

16.
17.
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.  相似文献   

18.
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。  相似文献   

19.
20.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

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