Ca、Mn对镁合金凝固组织的影响

通过对镁合金铸锭后显微组织的观察,结合SEM能谱分析,研究了Ca、Mn元素对镁合金组织的影响.通过研究,发现Mg-2.0Mn的显微组织是由基体组织(α-Mg)和点状析出的组织(α-Mn)组成;Mg-0.5Ca的显微组织是由(α-Mg)基体组织和非平衡结晶形成的Mg2Ca相组成.Ca、Mn对镁合金的组织均有细化作用,当同时加入Ca、Mn合金元素时,镁合金的显微组织会更加细小,晶粒趋于均匀圆整,同时第二相颗粒减少.其原因是:Ca提高了Mn与镁合金的润湿性,提高了Mn的溶解与扩散能力,温度降低Mn原子从合金中析出,为合金凝固提供了大量的晶核.     

Ca对AE41合金的显微组织和力学性能的影响

研究了Ca的低合金化对稀土镁合金AE41显微组织和力学性能的影响。研究结果表明，Ca能显著地细化合金的铸态组织，并在合金的显微组织形成热稳定性很高、分布均匀的弥散强化相颗粒Mg2Ca。少量的Ca加入AE41能有效地改善合金的力学性能，尤其是提高在150℃－225℃温度范围内的强度和蠕变抗力。在175℃，70MPa条件下，加入了0．1％Ca后，合金的蠕变速率比基体合金降低了一个数量级。从综合性能的角度考虑，在AE41中Ca的加入量以0．1％为宜。     

Ca含量对Mg-8Sn合金组织与力学性能的影响

利用金相显微镜(OM)、X射线衍射分析(XRD)、扫描电子显微镜(SEM)等手段观察分析了铸态Mg-8Sn-xCa合金组织,并且通过显微硬度及压缩强度等性能,研究Ca含量对Mg-8Sn合金力学性能的影响。研究发现,Ca的添加使得Mg-8Sn合金组织中形成明显的棒状及针状CaMgSn相,随着Ca含量的增加,CaMgSn相尺寸明显变大,并且其有效细化了基体的晶粒尺寸。Ca含量的添加使得合金强度明显提高,但使合金塑性降低;Mg-8Sn-1Ca合金在强度明显提高的同时,保持了较好的塑性;当Ca含量大于1%时,合金强化效果减弱,材料塑性下降明显。     

超音速气雾化高硅铝合金粉末高温加热组织及性能演变

本文利用超音速气体雾化法制备快速凝固高硅铝合金粉末，对合金粉末在不同温度加热处理后合金相组合，显微组织及显微硬度的变化特征进行系统研究。结果表明合金粉末在加热过程中，随着加热温度的升高，其组织中非平衡相逐渐转变为平衡相，同时有新的第二相沉淀析出，合金组织第二相在高温加热过程中有粗化趋势，合金显微硬度在低温加热时有下降趋势,随后升高温度不再下降，而是维持在相对稳定的水平。     

热处理对Co-Ni-Al合金显微组织和力学性能的影响

制备不同成分的Co-Ni-Al合金,研究热处理对Co-Ni-Al系磁控形状记忆合金显微组织和力学性能的影响。采用光学显微镜、X射线衍射仪及显微硬度计等研究热处理工艺对Co-Ni-Al合金显微组织、相结构及力学性能的影响。研究结果表明:热处理使合金晶粒长大,使合金晶粒中出现簇状新相,γ相显著长大且含量明显变多。随着热处理温度的提高,合金β相、γ相、簇状相长大且γ相含量变多,合金抗压强度提高。     

2197铝锂合金的组织和性能

通过力学性能测试和显微组织观察研究了2197合金组织和性能之间的关系。结果表明,2197合金具有中等强度,小的各向异性,强的热稳定性。该合金在T8状态下能获得最佳的强度和塑性配合,在T6峰时效状态以析出少量δ′相、θ′相和T_1相联合强化为主。在2197合金的相组成中,T_1相析出数量不占主导地位,Al_6Mn弥散质点的析出有利于减小各向异性。2197合金中Li含量较低,使其呈现较强的热稳定性。     

C47A铝锂合金组织和性能的研究

通过力学性能测试和显微组织观察研究了C47A合金组织和性能之间的关系. 结果表明: C47A 合金具有强度高、各向异性小、热稳定性好等特点;该合金在T6状态下, 主要的析出强化相是δ′相、θ″相以及少量的T1相. 而在T8状态下, 其主要强化相是δ′相和T1相, 预变形促进了T1相的析出, 提高了合金的时效强化效果. C47A合金在107, 150 ℃热暴露表现出良好的热稳定性;但在200 ℃热暴露时, 由于T1相显著粗化和δ′相的熔解, 热稳定性降低.     

Ca的不同加入量对AZ63镁合金组织性能的影响

选用AZ63镁合金为基体材料,通过合金化制备、光学金相显微分析(OM)等测试分析方法,研究了不同含量的合金元素Ca(1.0%、1.5%、2.0%和2.5%)对AZ63镁合金微观组织的影响。研究结果表明:在AZ63镁合金中添加适量钙进行合金化可以细化其铸态组织,提高硬度,此外,适量的合金元素Ca能够改善镁合金的冶金质量;Ca元素含量为2.0%时,合金具有较好的显微组织和综合性能。     

预变形对含钪Al-Cu-Li合金组织与性能的影响

采用显微组织观察和室温拉伸试验等手段，研究了形变时效中预变形对含钪Al-3.5Cu-1.5Li-0.12Zr合金微观组织与拉伸性能的影响。结果表明：时效前的预变形能促进T1（Al2CuLi）相弥散细小析出，显著提高合金强度，使时效峰值提前。合金强度随预变形量和时效时间增加而增加，到峰值后，随预变形量增加和时效时间的延长，T1相长大粗化，合金强度和塑性降低。在本试验条件下该合金合宜的预变形量为3．5％～5．6％。     

Ti-6.5Al-2.5Sn-4Zr-0.7Mo-1Nb-0.2Si合金的性能与显微组织

在实验室条件下，研究了Ｔｉ６．５Ａｌ２．５Ｓｎ４Ｚｒ０．７Ｍｏ１Ｎｂ０．２Ｓｉ合金的热处理、常温机械性能和显微组织。结果表明，合金的机械性能优异，达到了俄罗斯同等产品水平；合金显微组织是大量α相＋少量转变β相的两相组织，并阐述了机械性能和显微组织随热处理变化的规律。     

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.