内置横向插板加强型管节点静力强度研究

主管内设置横向插板是改善焊接圆钢管结构承载能力的一种方法。为了研究横向内置插板对节点静力强度的影响，采用有限元方法，对62个加强与未加强的T形节点模型进行了有限元模拟和分析。调查了节点区域和内置横向插板在静力加载过程中的变形过程。通过对模型参数的研究发现：内置横向插板能够提高T形节点的静力强度，但当T形节点承受轴向压力作用时，静力强度的提高对插板长度和厚度的变化不敏感。插板的厚度可按照构造措施选取，长度不能小于支管的直径。     

现浇单向板肋梁楼盖结构实荷试验

通过某工程实例，介绍了用水加载的方式对某框架结构现浇单向板肋梁楼盖进行结构实荷试验的全过程．     

Development of in vitro models to demonstrate the ability of PecSys®, an in situ nasal gelling technology,to reduce nasal run-off and drip

Many of the increasing number of intranasal products available for either local or systemic action can be considered sub-optimal, most notably where nasal drip or run-off give rise to discomfort/tolerability issues or reduced/variable efficacy. PecSys, an in situ gelling technology, contains low methoxy (LM) pectin which gels due to interaction with calcium ions present in nasal fluid. PecSys is designed to spray readily, only forming a gel on contact with the mucosal surface. The present study employed two in vitro models to confirm that gelling translates into a reduced potential for drip/run-off: (i) Using an inclined TLC plate treated with a simulated nasal electrolyte solution (SNES), mean drip length [±SD, n = 10] was consistently much shorter for PecSys (1.5?±?0.4?cm) than non-gelling control (5.8?±?1.6?cm); (ii) When PecSys was sprayed into a human nasal cavity cast model coated with a substrate containing a physiologically relevant concentration of calcium, PecSys solution was retained at the site of initial deposition with minimal redistribution, and no evidence of run-off/drip anteriorly or down the throat. In contrast, non-gelling control was significantly more mobile and consistently redistributed with run-off towards the throat. Conclusion: In both models PecSys significantly reduced the potential for run-off/drip ensuring that more solution remained at the deposition site. In vivo, this enhancement of retention will provide optimum patient acceptability, modulate drug absorption and maximize the ability of drugs to be absorbed across the nasal mucosa and thus reduce variability in drug delivery.     

Determination of material properties of orthotropic plates with general boundary conditions using Inverse method and Fourier series

Determination of material properties of orthotropic plates with general elastic boundary supports using the Inverse method is presented in this paper. The material properties were identified through updating four parameters in the governing equation of a symmetrically laminated thin plate. The sum of the squared difference of the natural frequencies obtained from modal testing was minimized using the Forward method. The displacement function was expressed as a 2-D Fourier cosine series supplemented with several terms in the form of 1-D series. A classical solution was derived by letting the series exactly satisfy the governing differential equation and all the boundary conditions at every field and boundary point. In the Inverse method, the series expansions for all the relevant derivatives of the eigen frequencies were obtained through term-by-term differentiations of the displacements. Many simulations were done but one numerical example is presented to demonstrate the accuracy and convergence of the solutions.     

Inertia force effects in the non-Newtonian couple stress squeeze film between a sphere and a flat plate

On the basis of the Stokes micro-continuum theory together with the method of mean averaged inertia, the influences of fluid inertia forces on the non-Newtonian squeeze film characteristics between a sphere and a flat plate have been presented. Comparing with the case of a non-inertia non-Newtonian lubricant, the consideration of fluid inertia forces provides a longer squeeze film time especially for the squeeze film operating with a lower film height, and a larger non-Newtonian parameter and density parameter. It prolongs the life of squeeze films.     

令纸包装机的优化设计

随着劳动力成本的日益提高，手工包装机逐渐被自动令纸包装机替代。自动令纸包装机虽替代了一部分手工劳动，     

高速铁路无碴轨道板封边方案的技术经济比选

结合京沪高速铁路无碴轨道轨道板实际情况,探讨了轨道板和底板之间的缝隙边缘密封方案,通过对封边采用的角钢方案和砂浆方案从技术经济角度进行了对比分析,最终选定角钢封边方案,为今后高速铁路无碴轨道施工提供了一定指导。     

基于Pro/Mechanica的扶梯梳齿支撑板的强度设计

在自动扶梯中,梳齿支撑板作为在每个出入口安装梳齿板的平台,其作用主要是保证梳齿板能正常啮合,并且在梳齿板发生意外的情况下,触动安全开关,使整台扶梯停止;在传统设计中,对于形状较复杂的梳齿支撑板,难以得到较精确的变形,但采用Pro/Mechanica能够快速的进行有限元分析,得到比较精确的结果。     

高铬铸铁工作辊在中厚板轧机上的应用

简要介绍中厚板轧机工作辊应具有的基本条件,详细阐述了髙铬铸铁工作辊的特点及酒钢中板使用髙铬铸铁工作辊的效果,对国内其它中厚板轧机工作辊材质的选用有借鉴作用。     

Numerical simulation of full penetration laser welding of thick steel plate with high power high brightness laser

Full penetration laser welding was carried out on a 10 mm steel plate using a 16 kW maximum power continuous wave thin disk laser. Upper surface and lower surface of molten pool were observed synchronously with two high speed CCD cameras during the welding process. The lower surface was much longer and more unstable than the upper one. A three dimensional laser deep penetration welding model in which volume of fluid (VOF) method was combined with a ray-tracing algorithm was used to simulate the dynamic coupling between keyhole and molten pool in laser full penetration welding. The calculated weld cross-section morphology and molten pool length on both upper side and lower side agree well with experimental results. Evolution of molten pool in lower side during full penetration laser welding was analyzed, periodical features of energy coupling, molten pool behavior and keyhole dynamics in laser full penetration welding were identified and discussed.