天然气应用于可控气氛制备对炉内碳势的影响

针对可控气氛发生炉炉气成分对热处理炉内碳势的影响,对吸热式可控气氛发生炉不同的原料气进行分析比较.研究表明:分别以丙烷气和天然气为原料气制备吸热式可控气氛时,天然气要优于丙烷气.     

吸热式可控气氛发生炉的最优工作温度的研究

研究表明:以丙烷气为原料气制备吸热式可控气氛时,吸热式可控气氛发生炉工作温度应选择在1 000～1 050℃之间;以天然气为原料气制备吸热式可控气氛时,吸热式可控气氛发生炉工作温度应控制在1 050～1 100℃之间.     

滴注式气氛密封箱式多用炉及其机组的技术发展

回顾了可控气氛的发展趋势,介绍了滴注式气氛密封箱式多用炉及其机组的技术特性,同时对多用炉的密封性、气氛的均匀性以及气氛的碳势控制等问题作了技术思考.指出在滴注式气氛密封箱式多用炉中能够进行渗碳、碳氮共渗、光亮淬火、球化退火以及复碳等多种热处理,该多用炉及其机组是一种自动化程度高、生产柔性大、适用性强的多用炉生产线,它为我国广大中小型热处理企业的工艺装备提供了比较适用的炉型和品种,发展前途十分广阔.     

新型推链式可控气氛钎焊炉的研制

新型推链式可控气氛钎焊炉,在国内首次采用了在氮基气氛保护下,应用液氮自动喷淋冷却,一次性完成工件钎焊、光亮淬火的新工艺。本文重点介绍了该炉温度控制系统、碳势控制系统及冷却系统     

9310钢热处理工艺研究

本文采用可控气氛炉对9310钢新材料的热处理工艺参数进行了试验,分析了力学性能试样的重复性及炉内碳势对剥层试样浓度和HRC60处深度的影响。结果表明,9310钢淬火后力学性能可以达到要求并且重复性很好;在相同的试验条件下,9310钢可以满足技术条件要求;炉内碳势越高,剥层试样碳浓度越高;炉内碳势控制在w(C)0.98%左右时,可同时保证表面碳浓度梯度和HRC60深度两个技术指标。     

连续退火机组碳套辊结瘤原因分析及查找方法

对碳套辊结瘤原因进行了原因分析,分析结果表明:碳套辊表面凹坑为结瘤提供了附着位置;粉尘、残油残铁、氧化铁皮等为碳套辊结瘤的主要原料;通过调整炉内气氛、监控清洗段电导率、刷辊电流等措施有效降低了碳套辊结瘤发生,通过差速法可快速锁定结瘤范围.     

烧结钢烧结过程中的气氛控制及其对性能的影响(1)

烧结气氛的正确选择及其控制对烧结后部件的性能至关重要。这里所谓的控制主要是指对气氛中氧及碳浓度（含量的）控制，因为两者均对烧结的质量及其后部件的力学性能，烧结表面质量等具有决定性的作用。本文综述了PM钢烧结过程中所用的不同的烧结气氛，阐述了不同气氛的作用及其影响，着重分析了不同气氛中碳势及氧浓度的控制，并举例说明。     

烧结钢烧结过程中的气氛控制及其对性能的影响(2)

烧结气氛的正确选择及其控制对烧结后部件的性能至关重要。这里所谓的控制主要是指对气氛中氧及碳浓度（含量）的控制，因为两者均对烧结的质量及其后部件的力学性能、烧结表面质量等具有决定性的作用。本文综述了PM钢烧结过程中所用的不同的烧结气氛，阐述不同气氛的作用及其影响，着重分析不同气氛中碳势及氧浓度的控制，并举例说明。     

基于炉气分析熔池碳含量的在线测量

采用飞行质谱技术构造的炉气分析系统,依据质量平衡原理,结合炉气流量计测得的炉气流量,计算出了熔池的瞬时脱碳速度,采用碳积分模型或者碳曲线拟合模型预测计算熔池中的碳含量,为解决熔池碳含量在线测量分析技术的难题提供参考.     

氮基可控气氛连续纤焊炉成套设备的研制

研制的氮基可控气氛连续钎焊炉,成功地解决了钢质零件的铜钎焊问题。是具有发展前途的新型钎焊设备。     

论从实践理解世界的物质性和自然世界的先在性

马克思主义唯物论是一种物本主义形态的唯物论,还是一种超越物本主义形态、从实践理解世界的本质相关问题的实践的唯物主义的唯物论?这是一个我们必须搞清楚的有关马克思主义唯物论的本质规定性和精神实质的重大问题.在考察物本主义的唯物论及其思维方式的局限性的基础上,揭示了马克思主义唯物论是现代的、实践的唯物主义,并重点研讨了马克思主义唯物论关于从实践理解世界的物质性和自然世界的先在性的原理,以期为马克思主义唯物论进一步阐明人类世界的实践性原理奠定基础.     

Effect of cyproheptadine on the ultrastructure of the neurons of the arcuate nucleus in the hypothalamus of the rat

The data are presented on changes in the rat arcuate nuclear neuron ultrastructure after using cyproheptadine (peritol, Egyt Pharmaceutical Works, Hungary) in a water suspension at a dose of 20 mg/kg once daily during 7 successive days and twice a day within 10 days. It was shown that cyproheptadine decreases the functional activity of the arcuate nuclear neurons, depending on the total amount of the drug used. Cyproheptadine-induced inhibition of the forming neurohormone release from neurons is likely to be one of the mechanisms of its therapeutic effect in Itsenko-Cushing's disease.     

Characteristics of the sympathetic innervation of the nictitating membrane and of the vasculature of the nose and tongue of the cat

Vasomotor responses from the nasal mucosa and tongue, and contractions of the nictitating membrane, were recorded on stimulation of the cervical sympathetic or internal carotid nerves. Preganglionic sympathetic nerve fibres which elicited a membrane response possessed a lower threshold than those which evoked nasal vasoconstriction, while the latter displayed a lower threshold than fibres which evoked tongue vasoconstriction. The sympathetic vasodilator fibres to the tongue whose activity was revealed after alpha-receptor blockade, had a similar threshold to the vasoconstrictor fibres. Membrane contraction, nasal vasoconstriction and occasionally tongue vasoconstriction could be evoked by stimulating the internal carotid nerve. The postganglionic fibres innervating the nasal mucosa had a similar threshold to those of the nictitating membrane, which may indicate that there are small myelinated fibres innervating the mucosa. The preganglionic compound nerve action potential had four major components, S1-S4. S1, S2 and usually S3 fibres were associated with membrane contraction; S2, S3 and sometimes S1 fibres were associated with nasal vasoconstriction; and S3, usually S2 and occasionally S1 fibres were associated with vasoconstriction in the tongue. It is concluded that each of these three groups of nerve fibres, but not S4 fibres, may include fibres associated functionally with the three effectors. There was a considerable difference between the relative amplitude of the responses of the three effectors elicited by stimulation of the cervical sympathetic nerve at frequencies between 0.2 and 2 Hz. Vasoconstrictor responses were relatively larger than membrane contractions suggesting differences in the mechanisms of neurotransmission at the neuroeffector junctions.     

Structure of the attachment of the vocal ligament to the perichondrium of the thyroid cartilage

The ventral attachement of the ligamentum vocale of eleven larynges (new-born and adults has been studied in sagittal, frontal and horizontal sections. 1. Supplementary to the known structure of the ventral attachement of the ligamentum vocale we have noticed collagen fibers which ascend in the inner angle of the thyroid cartilage and which partly cross to the other side. Sometimes a few fibers which are running downward have been observed. This structure of the attachement must be more firm than the known structure. 2. Moreover it has been observed that a lot of the angles of the crossing collagen fibers in the cartilage of the lamina mediana (near the attachement of the ligamentum vocale) are right-angled, whereas the angles of the fibers which lie in the laminae laterales in their majority are acute-angled. This phenomenon also is interpreted as a structure which makes the lamina mediana firmer. The fact, that this structure is not so evident in the specimens of the new-born as in those of the adults indicates that there are postnatal changes in the structure of the lamina mediana.