预应力钢筋混凝土安全壳侵彻数值模拟分析

应用显式动力有限元程序，对核反应堆预应力钢筋混凝土安全壳进行了卵形头弹体侵彻数值模拟分析。采用HJC混凝土累积损伤材料模型，采用分离式三维有限元计算模型，分析了预应力钢束及预应力对弹体侵彻过程的影响。     

两点应变测量法和岩石力--凿深特性的实验研究

岩石的力—凿深特性是冲击钻进波动力学研究的一个重要边界条件和基本参量,利用两点测量法对岩石的动态凿入特性进行实验研究,并考虑了钻头端部变截面和凿入速度对力—凿深特性的影响,运用最小二乘法的曲面拟合,得出了更为精确的凿入系数和粘度系数值,并在实验的基础上综合得到粘弹性类型岩石,即泰山花岗岩力 凿深特性的一般模式.     

两点应变测量法和岩石力—凿深特性的实验研究

岩石的力—凿深特性是冲击钻进波动力学研究的一个重要边界条件和基本参量,利用两点测量法对岩石的动态凿入特性进行实验研究,并考虑了钻头端部变截面和凿入速度对力—凿深特性的影响,运用最小二乘法的曲面拟合,得出了更为精确的凿入系数和粘度系数值,并在实验的基础上综合得到粘弹性类型岩石,即泰山花岗岩力 凿深特性的一般模式.     

活性炭共吸附现象对有机蒸气穿透容量的影响

在空气避有机蒸气的气相色谱分析方法研究中，为获得可靠的采样效果，探讨了活性炭对共存有机蒸气的共吸附与穿透容量的关系，试验了四种有机蒸气共存时和组分的有采样效率。结果表明，共吸附使所有共存有机蒸气的穿透容量下降，共吸附物质愈多，穿透窝量下降愈严重。对二种和四种有机蒸气的共吸附，使丙酮的穿透容量下降２１．９％和４１．７％，四组分共存时，丙酮，丁酮，环已酮、甲苯的穿透窝量分别为５．６、５．０、９．７、１     

关于砂土液化判别方法的探讨

本文通过静力触探锥尖阻力与标准贯入击数的回归关系，提出了以《建筑抗震设计规范》（GBJ11－89）为基础的饱和砂土液化静力触探判别方法及液化指数的计算方法。     

粉末冶金材料激光深熔焊接光致等离子体行为及控制

采用LSM2 4 0型全自动CO2 激光焊接机焊接粉末材料 ,研究不同粉末材料产生等离子体所需的临界激光功率。粉末配方为 :Fe粉 +15 %羟基Fe粉 ,Co粉 ,Ni粉 +15 %羟基Ni粉三种试样。研究结果表明 ,Fe ,Co ,Ni三种试样在CO2 激光作用下产生金属蒸气时的临界激光功率密度IC 为ICFe >ICCo >ICNi;等离子体得以有效控制的下限临界气流量QS 为QFeS 相似文献   

Heat penetration characteristics and shelf‐life studies of mushrooms in brine processed in retort pouches

White button mushrooms were washed, blanched and cut longitudinally into two halves. 100 g mushroom halves was placed into each retort pouch and 90 ml hot brine (2% salt, 0.1% citric acid) was added. Retort pouches (105 µm thick) had an outer polyester layer (12.5 µm), a middle aluminium layer (12.5 µm) and an inner cast polypropylene layer (80 µm); pouch size was 20 × 16 cm, seal size 10 mm and lip size 4 mm. Pouches were fixed with thermocouples for recording the core temperature of the mushroom pieces, using a data recorder and a computer. After sealing and over‐pressure retorting at F₀ = 9.6, the pouches were stored at the ambient conditions. The heat penetration parameters were calculated. The heating curve obtained was logarithmic in nature. Sensory evaluation of mushroom curry prepared from the stored mushrooms showed that the product had high acceptability (7.9 on a scale of 10) which reduced very slightly (to 7.5) during storage for 12 months. No deformity, leakage or spoilage was noticed and the product remained sterile and acceptable even after 12 months of storage at the ambient conditions (20–30°C). Copyright © 2004 John Wiley & Sons, Ltd.     

Numerical Simulation of Rigid Projectile''''s Normally Penetrating into Granite Targets

The process of penetrating into granite was simulated by using program LS-DYNA3D. The granite was represented by the isotropic elastic-plastic model with failure criterion and the projectile was modeled by rigid model. The depth of penetration from simulations is identical with experiments. Penetration deceleration vs striking velocity was acquired at the same time, which can assist in the design of penetration weapons with payload and fuse. Through numerical simulation, that material model is considered with straightforward physical meaning, a few parameters which can be determined easily are more practical for engineering calculation along with experiments.     

Microstructures and Properties of SiC／Al2O3 ／Al- Si Composites Prepared by Reactive Penetration

The composition, microstructures and properties of SiC/Al2O3/Al-Si composites formed by reactive penetration of the molten aluminum into the preforms of SiO2 and SiC were investigated. The composition of the composites was measured by X-ray diffraction ( XRD ). The microstructures of the composites were also measured by scanning electron microscopy (SEM) and optical microscopy. In addition, the factors affecting the properties of the composites were discussed. The experiments show that the mechanical properties of the composites depend on their relative densities and the sizes of the fillers“ SiC gains“. The denser the SiC/Al2O3/Al-Si composites, the higher their bending strength. As the filler “SiC gains“ become fine, the bending strength of the composites increases.     

矿物功能材料对混凝土氯离子渗透性的影响

在单因素影响方案的基础上 ,研究了多种磨细工业废渣及天然矿物材料的不同组合与叠加对混凝土氯离子渗透性的影响。通过试验研究和理论分析证实了硅灰与偏高岭土、粉煤灰、矿渣之间存在着“超复合叠加效应”,为合理选择矿物功能材料的种类及掺配方式 ,特别是偏高岭土的合理应用提供了技术思路 ,实现了矿物功能材料在提高混凝土抗氯离子渗透性方面的性能优化与降低成本的双重效用