基于ADAMS对柔性太阳能帆板的振动分析

通过建立的卫星模型,利用Adams/vibration模块对卫星柔性的太阳能帆板展开后进行振动分析,得出太阳能帆板的振动模态和特征值,以及频率响应曲线,通过分析得出系统的最大振型,为以后卫星结构和参数进行优化设计提供了依据。     

SB保温墙板连接件的试验研究

对外墙钢丝网架聚苯乙烯保温墙体的连接件进行了研究.主要研究了连接件与保温墙板之间的抗剪和抗拉性能,得 到了连接件的抗拉和抗剪承载力及破坏机理,为保温墙板的连接件设置提供了依据.     

Experimental and numerical analysis of air and radiant cooling systems in offices

This paper analyses office cooling systems based on all air mixing ventilation systems alone or coupled with radiant ceiling panels. This last solution may be effectively applied to retrofit all air systems that are no longer able to maintain a suitable thermal comfort in the indoor environment, for example in offices with high thermal loads.     

Bridging a Culture: The Design of Museo Soumaya

Fernando Romero and Armando Ramos of Fernando Romero EnterprisE (FREE) describe how the firm's design for an iconic museum in Mexico City, which adopted complex computational techniques, required them to develop an integrated and highly collaborative approach to design; with a central digital 3-D model being applied throughout the construction phase.     

An investigation of ballistic response of reinforced and sandwich concrete panels using computational techniques

Structural performance of nuclear containment structures and power plant facilities is of critical importance for public safety. The performance of concrete in a high-speed hard projectile impact is a complex problem due to a combination of multiple failure modes including brittle tensile fracture, crushing, and spalling. In this study, reinforced concrete (RC) and steel-concrete-steel sandwich (SCSS) panels are investigated under high-speed hard projectile impact. Two modeling techniques, smoothed particle hydrodynamics (SPH) and conventional finite element (FE) analysis with element erosion are used. Penetration depth and global deformation are compared between doubly RC and SCSS panels in order to identify the advantages of the presence of steel plates over the reinforcement layers. A parametric analysis of the front and rear plate thicknesses of the SCSS configuration showed that the SCSS panel with a thick front plate has the best performance in controlling the hard projectile. While a thick rear plate is effective in the case of a large and soft projectile as the plate reduces the rear deformation. The effects of the impact angle and impact velocity are also considered. It was observed that the impact angle for the flat nose missile is critical and the front steel plate is effective in minimizing penetration depth.     

Foamability and viscosity behavior of extrusion foamed PLA–pulp fiber biocomposites

This study addresses the effect of fiber reinforcement, chain extension, and physical foaming agent type on foam morphology and viscosity behavior of pulp fiber reinforced poly(lactic acid) (PLA) biocomposites. PLA reinforced with 0, 10, and 20 wt % of bleached kraft pulp fibers with and without chain extender were foamed using two different physical foaming agents (carbon dioxide and isobutane) by extrusion foaming. Densities, foam morphologies, and viscosities were systematically analyzed and compared from the produced foams. As a conclusion, low-density foams are produced with both foaming agents and fiber levels, fiber addition limiting cell growth. Isobutane provides better dimensional stability with narrower cell size distribution, whereas carbon dioxide enables lower foaming temperature. Chain extension is essential to achieve foam with low density and good cell structure. Contrary to nonchain extended PLA, addition of fibers reduced the viscosity of chain extended PLA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48202.     

河北省人造板20年回顾及发展展望

回顾总结河北省人造板20年发展经验和问题,以建设人造板强省为目标,切实转变发展方式,强化市场开拓,优化资源配置,调整企业结构,实施人才强企战略。     

木材加工与人造板行业信息平台的研发与建设

简要介绍了木材加工与人造板行业信息平台的研发与建设,介绍了网站建设运用的技术、网站定位、建设构架与内容。并简述了更好地研发,更好地分析、更好的工具的办站理念。     

切削参数对人造板切削力影响的研究

通过对中密度纤维板和刨花板的闭式切削实验,研究了不同锯齿前角、切削厚度、切削速度等参数对切削力的影响规律。结果表明:主切削力和法向力皆随前角的增大而呈减小趋势;通常情况下,相同锯齿前角切削时,刨花板的主切削力和法向力皆比中纤板大。切削厚度对切削力的影响显著,主切削力和法向力均随切削厚度增加而增加。切削速度对切削力的影响相对较小,随着切削速度的增加,主切削力和法向力均略有减小。     

实验检测人造板甲醛释放量的几点建议

人造板甲醛释放量是人造板检测的重要指标之一,也是人造板市场和国家监管的主要指标。本文就人造板检测中穿孔萃取法检测甲醛释放量的细节性事项提出一些建议。