微量合金元素Zr对Mo合金性能和显微组织的影响

采用粉末冶金方法制备Mo-Zr合金,研究了Zr的添加方式及添加量对Mo的拉伸性能和显微组织的影响.结果表明,添加合金元素Zr大大提高了Mo的力学性能.合金元素Zr以纯Zr形式加入较以ZrH2形式为佳,其添加量在0.1%时,合金性能最高.元素Zr少部分固溶到Mo基体中,大部分与合金中少量氧结合以ZrO2粒子相存在.     

Mo对TiC/316L不锈钢复合材料组织和性能的影响

为了提高TiC/316L不锈钢复合材料的力学性能,在TiC/316L复合粉末中添加不同质量分数的Mo元素,采用粉末冶金法制备TiC/316L不锈钢复合材料.通过对复合材料的显微组织分析,拉伸、摩擦磨损等力学性能的测试,研究Mo含量对复合材料的组织和性能的影响.结果表明,Mo的添加有利于复合材料的组织均匀化,从而提高复合...     

含Cu超耐腐蚀钢筋Cr9Mo1的实验研究

本文通过添加Cu元素和热轧工艺,制备了含有0.2%(质量分数)Cu元素的两组不同含C量的Cr9Mo1钢。利用拉伸试验机、光学显微镜(OM)及盐雾试验箱等,对比研究了添加Cu元素前后,Cr9Mo1钢力学性能、组织形貌及耐盐雾腐蚀性能的变化。结果表明,添加Cu元素均可显著提高Cr9Mo1钢的耐腐蚀性,但对力学性能及组织形貌无显著影响。低C钢组添加Cu元素后耐腐蚀性显著提高,强度和延伸率仅略有提高;高C钢组添加Cu元素后耐腐蚀性显著提高,强度略有提高,延伸率有所降低。热轧后的低C钢组的基体组织为混晶铁素体,高C钢组的基体为马氏体组织和少量δ铁素体。C含量的多少主要影响钢的力学性能,对耐腐蚀性的影响无显著差异。相较于含C量低的Cr9Mo1钢,含C量高的Cr9Mo1钢强度较高、塑性较差,但耐腐蚀性基本相同。     

WC-TiC-Ni硬质合金的制备与性能

以WC、(W,Ti)C和Ni粉末为主要原料,采用冷压-真空烧结法,制备WC-TiC-Ni硬质合金,研究Mo、Co等合金化元素的添加对合金显微组织力学性能的影响.采用扫描电子显微镜、三点抗弯曲、洛氏硬度等测试手段对烧结坯体致密化过程、显微组织演变及材料力学性能等进行表征.结果表明,通过技术控制,可制备出高致密度、良好力学...     

合金元素对2Cr13马氏体不锈钢组织及性能的影响

Ni,Mo,V均是影响13Cr型马氏体不锈钢性能的主要元素.研究了在普通2Cr13基础上添加不同含量的Ni,Mo以及微量V对其力学性能、耐腐蚀性能的影响.研究表明:单独添加Ni或Mo元素均未能明显改善2Cr13型马氏体不锈钢的综合力学性能,但同时添加适量的Ni,Mo等合金元素能明显提高材料的力学及耐CO2腐蚀性能.     

Mo添加剂对(Ti,V,Mo)C基金属陶瓷组织与性能的影响

结合BSE显微组织观察和EDS能谱分析、IPP统计分析、XRD物相检测和密度、硬度、抗弯强度测试,研究了不同烧结温度和Mo添加量对(Ti,V,Mo)C基金属陶瓷显微组织和力学性能的影响。研究表明:(Ti,V,Mo)C基金属陶瓷的显微组织中黑色芯相和灰色相共同构成硬质相,Mo添加剂主要作用于硬质相形成碳化物固溶体。随着烧结温度的升高,黑色芯相比例降低,灰色相区粗化明显,抗弯强度下降。当烧结温度为1 400℃,Mo添加量为6%时,(Ti,V,Mo)C基金属陶瓷的综合性能较佳。     

热处理对林产品干燥设备用金属材料组织及性能的影响研究

通过改善不锈钢的合金元素及热处理方式,为林产品干燥选材提供依据。以06Cr17Ni12Mo2不锈钢为基础,分别在其中添加微量Cu元素和Sn元素得到两种新的材料,对这三种材料进行不同退火温度下的热处理,分别对其组织、力学性能及耐蚀性进行分析研究。在微观组织方面,退火温度的升高会带来晶粒的长大,添加微量Cu元素也会使晶粒变大但添加微量Sn元素会使晶粒变小。在力学性能方面,添加铜元素对强度较小影响,但提高了延伸率,添加锡元素强度有所上升而延伸率变化不大。在耐蚀性方面,添加铜元素提高了耐蚀性,而添加锡元素同样也提高了耐蚀性但效果没有铜元素好。在06Cr17Ni12Mo2钢上添加Sn元素更符合林产品干燥设备用材的使用。     

TiC基对称成分功能梯度材料残余热应力分析

采用有限元方法对TiC基对称成分功能梯度材料 (SCFGM)中的残余热应力进行了理论计算。在此基础上 ,采用热压烧结工艺制备了表面无宏观缺陷的TiC(Mo ,Ni) x/TiC(Mo ,Ni) y/TiC(Mo ,Ni) x对称成分功能梯度材料。力学性能测试表明 ,对称成分功能梯度材料较之相应单一组分材料而言 ,在抗弯强度、断裂韧性等力学性能方面有较大程度的提高。这也表明 ,通过材料设计的手段可以改善材料的某些力学性能     

抗高温氧化Mo（Si,Al）_2粉末材料的自蔓延燃烧合成

本文主要研究Al添加量对Mo（Si,Al）2材料自蔓延燃烧合成过程以及物相转变的影响,以确立Al的最佳添加量,并分析自蔓延燃烧合成Mo（Si,Al）2材料的主要影响因素。研究结果表明,采用自蔓延燃烧合成法能够在室温环境下合成Mo（Si,Al）2,且反应物原料的粒径较小时,有利于Mo（Si,Al）2自蔓延燃烧合成的进行;当Al添加量x=0.3时,产物可完全转化为C40相;当Al添加量x=0.4时最合适,其产物为Mo（Si0.6,Al0.4）2。     

添加VC的TiB2基硬质材料研究

对添加VC的TiB2基硬质材料进行了研究。通过实验测定了硬度、横向断裂强度、高温强度以及耐磨性等性能，通过观察SEM照片研究了VC对TiB2基硬质材料组织结构的影响。综合各种指标，我们确定在TiB2-Fe—Mo硬质材料中VC的最佳添加量为0．5％。     

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)     

Comparison of rates of infection of two methods of emergency ventricular drainage

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.     

浅析《野草》的版画特征

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".     

四辊破碎机车刀架的改造

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。     

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.     

Comparison of the results of surgical and conservative treatment of fractures of the diaphysis of the tibia

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.