基于ADAMS的5-P4R并联机器人运动学分析及仿真

对一种改进后的三自由度5-P4R并联打磨机器人进行运动学分析,并采用CAE软件ADAMS进行运动学仿真。运用螺旋理论分析并联机器人的自由度,通过D-H法建立机构运动学方程并求取运动学逆解,运用CAD软件Solidworks建立并联机器人虚拟样机后导入CAE软件ADAMS环境中,对虚拟样机添加约束条件和驱动函数进行正向和逆向运动学仿真,验证了改进结构的可行性和稳定性。     

薄带连铸低碳钢中低熔点夹杂物控制研究

介绍了利用非水溶液电解法提取薄带连铸低碳钢中氧化物夹杂的方法,采用带有EDS系统的扫描电镜(SEM)研究了氧化物夹杂的三维形貌和化学成分,并通过热力学计算获得控制低熔点夹杂物生成所需成分范围。结果表明:低熔点Al2O3-Si O2-Mn O类夹杂物三维形貌为球形;随着钢液中酸溶铝含量的增加,夹杂物中Al2O3含量相应地增加,当钢液中[%C]=0.10、[%Si]=0.35、[%Mn]=0.90、夹杂物的熔点控制在1 200℃范围时,要求钢液中的酸溶铝含量很低,需控制在(1~5)×10-6。     

基于锥形电极的三维型腔精确加工方法研究

提出并分析了在利用圆锥形电极定长补偿方法分层加工三维型腔实验时,其第一层第二道加工切除残余突起后形成的实际加工深度与理论分层厚度的差异,该差异存在于加工时采用的关键加工参数补偿长度的误差。进而探究并提出了精确计算第二道加工时补偿长度的方法,并通过实验验证了该补偿长度的准确性,从而使第一层两道加工后形成的加工深度达到理论值。最后,利用该方法进行两层的三维型腔加工实验,由此证明型腔加工效果良好,满足型腔尺寸及形状精度的要求。     

Treatment of Liquefiable Ground by Resonant Compaction Using a Crisscross-Shaped Probe. Case Study at the Huaiyan Highway Site

Soil Mechanics and Foundation Engineering - The resonant compaction method using a crisscross-shaped probe was implemented in highway engineering projects for eliminating liquefaction in the east...     

并联管路气液两相流量均布特性数值模拟研究

为了确保大型液化天然气(LNG)板翅式换热器冷箱并联管路流量均布性,基于计算流体力学(CFD)方法,根据实际板翅式换热器冷箱并联管路的形式,简化并建立了并联管路物理模型,模拟研究了气液两相流的流量均布特性。研究结果表明:当气液两相流速固定时,增加两相的体积含气率会先降低后提高流量分配的均匀性;当两相的体积含气率固定时,流量分配均匀性随流速的增加而变好。不同管路布置方式对并联管路流量分配影响不同。为提高并联管路流量的均布性,当管道水平布置时,优先考虑水平上进下出式;当管道垂直布置时,优先考虑垂直向下流入式。上述研究成果将为大型LNG板翅式换热器冷箱并联管路运行参数和布置方法的设计提供重要的理论依据。     

基于Aspen Plus的氯乙烯精馏过程模拟及优化

采用Aspen Plus软件对氯乙烯精馏过程中的低、高沸塔进行了模拟,讨论了馏出比、进料板位置和回流比等参数对精馏过程的影响,得到了适宜的操作条件。     

"凤凰于飞"婚礼主题展厅空间设计浅析

中式风格展示空间设计并不是简单的元素符号堆积,而是通过提取和完善传统中式元素的文化本质,结合现代设计趋势,去创造富有传统艺术魅力的现代展示空间.项目以中式婚礼的历史文化为基础,以中式婚礼的礼仪为纽带,结合中式婚礼文化设计符号,运用主题展厅内部空间,融合主题视觉元素,让观众观展游览的同时犹如进入一场完整的中式婚礼,以此阐释婚礼文化别样的韵味.     

Effect of Temperature on Oxidation Behavior of 3‐Dimensional C/SiC Composites Coated by Different Structural SiC and a‐BCx Coatings in Static Wet Oxygen Atmosphere

The effect of temperature on oxidation behavior of 3‐dimensional C/SiC composites coated with SiC and a‐BC_x coatings was investigated. Below 1000°C, C/SiC composites with SiC coating (sample SSS) showed low residual strength, while the composites with a‐BC_x coating (sample BBB) and the composites with a‐BC_x/a‐BC_x/SiC coatings (sample BBS) showed high residual strength. Above 1000°C, samples SSS and BBS showed high residual strength, while sample BBB showed the opposite results. Sample BBS presented better oxidation resistance during 700–1200°C. The oxidation temperature made an effect on self‐sealing mode of sample BBS.     

Metal‐Free Autoxidative Nitrooxylation of Alkenyl Oximes with Molecular Oxygen

A metal‐free aerobic autoxidative nitrooxylation of alkenyl oximes mediated by tert‐butyl nitrite is described. Molecular oxygen is used as the oxidizing reagent, avoiding use of organic trapping reagents such as 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO). The desired products were obtained in generally high yields.

     

Development and analysis of a novel collagen composite encapsulating a natural pharmic amino acid,dencichine

In this work, we have conducted a blend of type I collagen and dencichine under acid conditions, followed by investigating the intermolecular interactions between the two components. Fourier transform infrared spectroscopy (FTIR), molecular modeling methods, the circular dichrorism (CD) measurement, and X‐ray photoelectron spectroscopy (XPS) studies inducate that the structure integrity of collagen is still maintained obviously after introducing dencichine. Furthermore, we also analyze the mechanism of the combination, which is just more than hydrogen bonding. Moreover, differential scanning calorimetry (DSC) reveals that compared to pure collagen, dencichine could promote the thermalstability of collagen‐dencichine composite sponge (CDCS) with the increasing content of dencichine. Atomic force microscopy (AFM) is utilized to determine the morphology changes of collagen by inducing dencichine. The fibril aggregation occurs due to the crosslinking with dencichine and the fibrous structure of collagen after inducing dencichine still remains compact and clear, which is the foundation of its biological activity. The present study, reveals that intermolecular interactions exist in the CDCS indeed, which is benefit for the development of new biological material and fabrication of novel functionalized hemostatic biomaterials. POLYM. COMPOS., 37:2027–2036, 2016. © 2015 Society of Plastics Engineers