电磁悬浮浇铸法（LCP）

电磁悬浮浇铸法是通用电气公司最新开发的一种连铸技术。该法用一个电磁悬浮场代替结晶器支承和盛装柱状凝固金属。为了抵制金属柱的引力和静压,该法消除了凝固金属与浇铸容器冷却壁接触面的磨擦和吸附。悬浮浇铸法可将固有的高的浇铸速度和极好的尺寸控制巧妙地结合在一起,并可从浇铸器顶部连续排出凝固产品。其中最重要的是电磁场对凝固前和凝固期     

低成本无耐火材料悬浮熔炼工艺

美国Inductotherm公司与塔斯卡卢萨的亚拉巴马大学联合开发采用了一种新工艺—无耐火材料无容器的熔炼,该熔炼工艺称为磁悬浮熔炼。熔炼系统采用电感应技术,即在电磁场中熔化金属坯块并使熔融金属悬浮起来,电磁场产生搅拌作用并使之均匀熔炼,减小温度梯度和促进脱气。     

冶炼

改良的金属悬浮熔炼法采用高频电流(450千周)可以进行难熔金属无坩埚熔炼、混合和固化。研制者(佛罗里达大学),目前准备通过专利公开发表该工艺中至少两方面的成就。如所周知,目前铝生产使用电磁悬浮技术混合金属元素。但实践表明金属悬浮的不完全。科学院研究者的工艺可使金属完全悬浮。其结果表明金属     

稀土永磁悬浮阵列的电磁导向结构设计

永磁阵列悬浮结构(Magnetic Array Suspension,简称MAS)与管道物流系统相结合，为新型物流运输系统带来了新的机遇，但永磁悬浮结构在实现垂向零功率自稳定悬浮的同时，存在着横向侧偏力的挑战。本文以MAS悬浮结构为研究对象，探索一种能够实现横向可控的电磁阻尼系统结构。首先，在ANSYS有限元仿真环境下探究MAS悬浮机理，分析垂向悬浮力同悬浮间隙的变化关系，及横向侧偏力随横向间隙变化的规律；其次，针对悬浮结构特点，提出了斥力型和吸力型两种电磁导向方案，并研究分析了两种方案下磁场分布特点及磁密走势；最后，在三维模型的基础上，分析并总结了电磁激励、横向间隙与侧偏力的力学关系。仿真结果表明，斥力型方案下，导向力与横向间隙呈近似线性关系，但受MAS永磁体影响，需要初始电流用于抵消永磁吸力；吸力型方案中，导向力与横向间隙呈非线性关系且不受永磁体影响。综合而言，在相同条件下，吸力型方案更加可行，磁能利用率更高，为研究永磁悬浮系统的性能提升和工程应用提供了一种可行的结构设计方案。     

电渣冶金技术的最新发展趋势

简要回顾了电渣重熔工业生产50年的发展历史,重点对近年来电渣冶金新技术进行了介绍和评价,包括快速电渣重熔,双极串联电渣连铸技术,特厚板坯电渣重熔,大型电渣重熔钢锭凝固偏析控制,可控气氛电渣炉和电渣液态浇铸技术。在新的发展阶段,电渣冶金技术向高效、节能、环保和满足更高质量方向发展。     

使用CO2-Ar混合气体悬浮精炼不锈钢

 不锈钢生产成本的降低以及CO2在炼钢过程中的资源化利用是当前冶金工作者研究的热点之一。提出了一种利用电磁悬浮精炼不锈钢脱除其中碳、硫的方法;从动力学的角度分析了碳、硫等元素在悬浮精炼不锈钢熔体状态下脱除的原理。试验结果表明,CO2可以在电磁悬浮状态下代替O2对不锈钢进行精炼,此状态下不锈钢试样组分挥发少,[w(C)]可以脱除到0.04%;脱硫效果与试样中[w(C)]有关,[w(C)]越高,脱硫效果越好;改变气体流速和CO2分压等参数时,试样中的[w(Cr)]几乎保持一个常数,这说明使用CO2悬浮精炼不锈钢时不会伴随着重要元素铬的流失,保铬效果明显。     

电渣重熔高温合金凝固组织控制的研究进展

对近年来电渣重熔高温合金凝固组织控制的研究进展情况做了总结和归纳,包括重熔精炼过程、凝固过程、数值模拟研究的进展情况,以及近年来发展起来的控制熔池形状的新工艺新技术,如双电流回路电渣重熔技术、电渣重熔连续定向凝固技术等。     

高频感应悬浮熔融技术的应用

本文简要叙述了高频感应悬浮的基本原理与特点,同时对悬浮线圈的几何形状进行了研究,并成功的将悬浮熔融技术应用在金属中气体分析方面和炼铁、炼钢温度范围的物理化学研究方面。     

闪速炉富氧炼铜电收尘器生产实践

详细叙述了贵冶闪速炉富氧生产以来电收尘器所存在的问题、原因,以及该厂在消化引进技术的基础上,进行闪速炉电收尘技术攻关所取得的成绩。     

特种冶金新进展

对特种冶金，包括真空冶金（真空感应脱气浇注、冷坩埚感应悬浮熔炼、电子束连续熔炼），等离子冶金及电渣冶金（真空电渣重熔、高压电渣重熔、电渣快速重熔、电渣复合技术）的新进展进行分析，并对发展方向予以评述。     

Role of clozapine in the occurrence of chromosomal abnormalities in human bone-marrow cells in vivo and in cultured lymphocytes in vitro

Bone-marrow chromosomes were examined from 38 mentally and physically retarded and two psychiatric patients who were being treated with a variety of neuropharmacologic drugs. Twenty of these patients used clozapine (Leponex). The clastogenic effects of clozapine in vitro were studied in the lymphocyte cultures of three patients--one free of hematologic disease and two who 6 months earlier had had agranulocytosis attributed to the use of clozapine. The mean frequency of cytogenetic abnormalities in the bone-marrow cells of patients who used clozapine was significantly increased (P less than 0.05). The two patients who had had agranulocytosis had a greater frequency of cytogenetic abnormalities in their cultured lymphocytes in vivo and in vitro than the patient free of hematologic disease. A clone with a 13/14 chromosome translocation was detected in one of the patients. As all patients received a number of drugs during the in vivo and in vitro studies no definite conclusions could be drawn regarding the role played by clozapine in the occurrence of chromosomal abnormalities.     

Difference in changes of plasma volume in two types of Goldblatt hypertension in rabbits

High plasma renin concentration (PRC) and hematocrit (Ht) were observed in hypertensive rabbits with one renal artery clipped and an intact opposite kidney (Group A), while rather low PRC and Ht in hypertensive ones with one renal artery clipped and the opposite kidney removed (Group B). Plasma volume (PV), blood volume (BV), and packed cell volume (PCV) were estimated in these two types of hypertensive rabbits, and also in sham-operated rabbits (Group C). In Group A, 4 weeks after clipping of a renal artery, PV was decreased and significant inverse correlations were observed between PV and the elevation of blood pressure and between PV and PRC. A significant correlation between PRC and the elevation of blood pressure was also found 4 and 12 weeks after the clipping. PCV was increased until 12 weeks after clipping. In Group B, PV was increased 1 and 4 weeks after clipping, then returned to the initial level. Ht was decreased 1 and 12 weeks, and PCV was decreased 12 weeks after clipping. These results would indicate that a high Ht seen in Group A was partly due to the decreased PV and partly due to the increased PCV, while, in Group B, a low Ht in early stage might be mainly due to the increased PV, but in the late stage, a decreased PCV appeared to play a role to lower Ht. PRC seems to be affected differently by PV in these two types of hypertension.     

Inhibitory effect of suramin in rat models of angiogenesis in vitro and in vivo

The aim of the present study was to test the ability of the chemotherapeutic agent suramin to inhibit angiogenesis in experimental models in vitro and in vivo. In the culture of rat aortic rings on fibronectin, suramin dose-dependently inhibited vascular cell growth, achieving the maximal effect (mean - 88% versus controls, P < 0.05) at 400 microg/ml. Image analysis showed that suramin could inhibit microvessel sprouting in fibrin from rat aortic rings as evaluated by the ratio between the cellular area and the mean gray value of the sample (sprouting index); suramin at 50 microg/ml significantly reduced the sprouting index from the control value of 0.35+/-0.04 to 0.14+/-0.02 mm2/gray level (P < 0.05). Likewise, the area occupied by cells was 19.2+/-1.8 mm2 as compared with 41.8+/-4.2 mm2 in controls (P < 0.05). In the rat model of neovascularization induced in the cornea by chemical injury, suramin at 1.6 mg/eye per day reduced the length of blood vessels (0.7+/-0.1 mm as compared with 1.5+/-0.1 mm in controls, P < 0.05). In the same model the ratio between the area of blood vessels and the total area of the cornea (area fraction score) was decreased by suramin from 0.19+/-0.02 in controls to 0.03+/-0.003 (P < 0.05). Suramin given i.p. at 30 mg/ kg per day markedly inhibited the neovascularization induced in the rat mesentery by compound 48/80 or conditioned medium from cells secreting the angiogenic protein fibroblast growth factor-3 (FGF-3). The area fraction score in control rats treated with compound 48/80 was 0.31+/-0.03, and this was reduced to 0.07+/-0.01 by suramin (P < 0.05). After i.p. administration of FGF-3 the area fraction score was reduced by suramin from 0.29+/-0.03 to 0.05+/-0.01 (P < 0.05). These results provide evidence that suramin exerts inhibitory effects on angiogenesis in both in vitro and in vivo models.     

Regional differences in suicide in Hungary in the light of registered cases of depression

Author made a revision on the theory published by Rihmer and alii in the year 1989. According to this theory the marked regional differences of suicide in Hungary are caused by the different discovery of the "endogen depression" (rate of diagnosed depression). So the lower is the diagnosis of depression the higher is the suicide rate in a given territory. They have seen a negative correlation between the number of working physicians and the suicide rates. Author made a reexamination on a correct database between 1985-1994. He has also made a study using the DSM-III-R diagnostic criteria in four counties of Hungary. His results deny the theory above mentioned. The rank-correlation of the number of GP and the suicide rates in Hungary in years 1985-1994 did not show correlation. So the underdiagnosis of the depressive disorders and the different number of GP are not the cause of the regional differences of suicide in Hungary.     

“全三脱”工艺流程中脱碳渣返回脱磷转炉利用

 为了在“全三脱”工艺流程中实现炉渣的高效循环利用,将[w((P2O5))]较低的热态脱碳炉终渣通过渣罐兑入脱磷炉继续发挥脱磷作用。分析结果表明,提高返回渣量及脱磷渣磷分配比均可显著降低脱磷炉石灰消耗量,当渣钢磷分配比及返回渣量控制合适时,脱磷炉可不加入石灰而使半钢磷质量分数达到目标值。对脱碳炉渣在脱磷炉冶炼中的再熔化过程进行计算分析,随着铁水中硅元素的氧化,脱碳渣碱度降低而不断熔化,逐渐发挥脱磷作用。在“全三脱”工艺流程中成功开发了转炉渣热态循环利用工艺,脱磷率提高约6%,返回脱碳渣加入量约为67.13 kg/t,石灰、轻烧白云石和萤石分别节约9.37、1.15 和2.45 kg/t,半钢温度提高约7 ℃。     

Epidemiology of trichinellosis in lynx in Finland

To examine the possibility of cytokine gene therapy in relation to pancreatic cancer, we evaluated the antitumor effect of human pancreatic carcinoma cells (AsPC-1) which were retrovirally-transduced with several kinds of cytokine genes. These cells were inoculated into BALB/c nude mice and their tumor volumes were assessed. The in vitro growth rate of the transduced cells was not different from that of a parental cell line. Among the transduced cells, human interleukin (IL)-6-transduced AsPC-1 and mouse granulocyte macrophage colony-stimulating factor-transduced AsPC-1 cells showed a significant retardation of tumor growth compared with a parental cell line. In the cases of AsPC-1 cells transduced with the human IL-2 or mouse IL-4 gene, small tumors were generated but thereafter they regressed completely. Histological examinations showed monocytic cell infiltration around the tumors of IL-2- or IL-4-producing cells. These data suggest that secretion of IL-2 or IL-4 from tumor cells can induce an antitumor effect even in the defective condition of mature T cells.     

Efficacy of lomefloxacin in treatment of nonspecific inflammatory diseases and in prophylaxis of postoperative complications in urology

Clinical and bacteriological efficacies of lomefloxacin and ofloxacin were comparatively estimated in the treatment of 104 urologic patients with nonspecific inflammatory diseases and in 36 urologic patients for prophylaxis of inflammatory complications after surgical interventions. The majority of the urinary tract pathogens i.e. Enterobacteriaceae spp. and gramnegative nonfermenting bacteria were highly susceptible to both the fluoroquinolones. The clinical and bacteriological efficacies of lomefloxacin amounted to 94.4 and 80.7 per cent and those of ofloxacin to 92 and 79.2 per cent respectively. The prophylactic use of lomefloxacin and ofloxacin was efficient in 94.7 and 94.1 per cent of the cases respectively. The antibacterial prophylaxis in urologic patients should be applied not only at the period of surgical interventions but also during the early postoperative period.     

PLC在高炉汽动式鼓风机监控系统的应用

鞍钢高炉15号鼓风机是VASi-9018型轴流式汽轮压缩机，通过技术改造，采用先进的电子控制技术，建成了全新的具有现代化水平的汽轮压缩机控制系统。