道次间冷却工艺对厚板芯部变形及组织的影响

利用道次间冷却技术对特厚钢板轧制开展道次间冷却工艺试验,研究轧制过程中的冷却参数对钢板变形渗透性和晶粒细化的影响规律。研究结果表明:道次间冷却工艺能够促进轧制变形向特厚钢板芯部渗透,在一定程度上消除了芯部带状组织;采用再结晶低温区连续轧制并在轧制道次间进行大强度冷却工艺,特厚钢板芯部组织晶粒明显细化,晶粒尺寸可达10~15μm;粗轧道次间的冷却工艺对轧制变形渗透的提高效果优于中间坯冷却工艺,并且道次间冷却强度的增大有助于进一步提高变形渗透性。     

坑透高精度CT层析成像测量方法试验研究

随着开采深度的增加,井田内地质构造条件越来越复杂,在综采工作面内必须采取适当的物探手段进行探测,而无线电磁波坑透技术在探测地质构造方面有较为成熟的技术手段和准确度。该文通过对比三种不同数据采集方法,利用自行研制的软件进行处理,分析CT层析成像图与实际揭露断层的对应情况。结果表明,当发射角覆盖范围越大,接收数据为21个时完成的探测效果较好。     

新型氧分离材料YBaCo4O7的氧行为与应用

YBaCo4O7是一种具有奇特氧吸附行为的材料,它在300℃左右的较低温度时就可以吸附其自身质量3%的氧,并且所吸附的氧在400℃可以快速脱附,同时具有稳定的循环特性,是一种非常有潜力的氧分离材料。介绍了YBaCo4O7的晶体结构及在外界温度变化时所产生的独特氧吸附/脱附特性;综述了晶格中不同位置的元素掺杂替代对其氧特性的影响;并对此类材料在透氧膜、脱氧纯化剂等方面的潜在应用进行了初步探索,最后总结了当前存在的一些问题并展望了可能的解决途径。     

Experiments on the study of effect of microparticles anomalistic penetration into solid bodies

At certain conditions interaction between high velocity (up to 3 km/s) flows of microparticles with dimensions 20–70 μm and solid bodies could result in their super deep penetration (SDP) into those bodies. For SDP-effect to be studied a number of experiments were carried out. The X-ray analysis of microparticles acceleration has shown the advantage of acceleration of microparticles in mixture with the extender (porofor) because it makes it possible to regulate the flow density, its velocity and impact duration by means of the extender concentration variation. Experiments have been performed on the impact of microparticle flows with velocities in the range 1–2.6 km/s on copper and iron substrates. Results of metallographic investigations of cross-sectional and lengthwise grinds of substrates indicate that some tungsten particles penetrate into a target. The diameter of channels in the substrate material, which are formed due to particles penetration, is in the range 2–15 μm.     

建筑力学教学反思

指出建筑力学是工程造价专业一门重要的专业基础课,理论性、系统性较强,包括理论力学、材料力学、结构力学三方面的内容,从情感教育、实践教育、教学评价、实例贯穿、教学手段等几方面阐述了自己对教学的一些反思,以达到指导实践的目的。     

Degradation mechanisms in shaped charge jet penetration

The mechanisms governing the penetration of shaped charge jets over the full range of stand-offs remain only partially understood. This paper explores various potential degradation mechanisms with the aim of identifying those that are most significant to the penetration process. The mechanisms addressed are: particle shape effects, particle separation, the extent of necking, the deposition of jet material and the effects of collisions of the particles with the crater wall. The study consists primarily of hydrocode simulations using the DERA Eulerian code cAst-Euler. In each case the effects of one or more copper particles impacting upon a semi-infinite Rolled Homogeneous Armour target are modelled. It is concluded from the study that particle shape and impact speed can be significant factors contributing to penetration degradation. Collisions at the side of the crater and tumbling of the particles are also likely to be adverse factors.     

回填土强夯地基检测实例分析

对某人工回填土强夯地基的静载荷试验及动力触探结果进行了分析,分析的结果表明对于人工回填土场地强夯质量的评价不能仅仅依靠平板静载荷试验,只有采用静载荷试验与动力触探相结合的方法才能更加准确地评价回填土体的承载力特性,发现有可能存在的加固深度不足等问题。     

煤粉防粘砂机理及煤粉代用品的发展

叙述了煤粉在型砂中的作用及煤粉的防粘砂机理，即气膜理论、焦碳膜理论、氢气还原理 论和光亮碳理论，介绍了煤粉对于型砂和环境的危害，以及煤粉代用材料在国内外的发展．     

静探和标贯在开封地区岩土勘察中的应用

本文作者根据多年来的工作经验，总结了一些常用的静探和标贯与土的状态及物理力学性质的关系，提出了具体的结论和意见，供同行们参考。