夹套管封板角焊缝裂纹原因分析及对策

本文针对夹套管封板角焊缝裂纹原因产生机理进行了分析,通过应力计算,指出因结构不合理是造成裂纹产生的根本原因,同时提出了解决问题的办法.     

卫生陶瓷机器人施釉厚度沉积率模型拟合软件模块的开发

釉料厚度沉积率模型是机器人自动施釉的重要依据.为了对卫生陶瓷产品的施釉机器人离线编程作业轨迹自动规划,实现施釉过程中卫生陶瓷产品釉料厚度的精确性和均匀性.采用MFC开发了釉料厚度沉积率模型功能模块.提出基于遗传算法拟合沉积模型方案,利用COM形式的VC与MATALB的混合编程实现模型拟合、模型分析功能,设计动态链接库,...     

有铅与无毒金红粉彩颜料性能之比较

采用SEM、EDS及色度、光泽度测定等分析方法对有铅和无毒金红粉彩颜料的性能进行了比较。结果表明:无毒金红颜料彩烤后与釉层结合良好不开裂,光泽度与外观呈色基本能达到含铅金红粉彩颜料的效果,可以应用于实际生产。     

High thermal conductivity of polyethylene nanowire arrays fabricated by an improved nanoporous template wetting technique

Generally polymer bulk structures and nanostructures are thermally insulative. In this study, we show that an improved nanoporous template wetting technique can prepare thermally conductive polymer nanowire arrays. The thermal conductivities of the fabricated high-density polyethylene (HDPE) nanowire arrays with diameters of 100 nm and 200 nm, measured by a laser flash method, are about 2 orders of magnitude higher than their bulk counterparts. The estimated thermal conductivity of a single HDPE nanowire is as high as 26.5 W/mK at room temperature. The high orientation of chains of the HDPE nanowires may arise from the integrative effects of shear rate, vibrational perturbation, translocation, nanoconfinement and crystallization. Findings in this study provide useful strategies on enhancing the intrinsic thermal properties of polymer nanostructures.     

HSQC (heteronuclear single quantum coherence) C-H correlation spectra of whole biomass in perdeuterated pyridinium chloride-DMSO system: An effective tool for evaluating pretreatment

Perdeuterated pyridinium chloride-DMSO-d₆ is an effective solvent system for whole cell biomass dissolution and NMR characterization. Employing this solvent system, semi-quantitative ¹³C-¹H heteronuclear single quantum correlation (HSQC) spectroscopy of untreated, steam, dilute acid and lime pretreated poplar biomass samples was readily accomplished. In an effort to demonstrate the efficacy and usefulness of this fairly new characterization technique, relative spectral intensities of the untreated and pretreated biomass samples were evaluated and compared. From the relative signal intensities of hemicelluloses in each system it was observed that hemicelluloses are being removed in various pretreatment conditions, but complete dissolution of hemicellulose was observed only with acid pretreatment. The relative changes in lignin subunits after pretreatment were estimated from the volume integration of resolved cross peaks of various lignin subunits. The degradation of lignin was observed in all pretreatments, though more significant changes were noticed after dilute acid and lime pretreatment. HSQC analysis results were in agreement with the composition analysis of pretreated biomass samples. Thus, this methodology broadens the application of whole cell NMR analysis in biofuel research.     

基于无线HART的智能仪表在线监控系统

为了充分利用传统HART仪表,提高控制系统的可靠性,减少现场仪表的维护量并降低维护费用,提出了一种基于无线HART协议的智能仪表在线监控系统,给出了系统的软、硬件设计思想和实现方法.     

四官能度过氧化物引发苯乙烯本体聚合动力学

用四官能度过氧化物引发剂聚醚聚过氧化碳酸叔丁酯(JWEB50)引发苯乙烯(St)本体聚合,采用膨胀计测微观动力学法,研究了聚合温度、过氧键浓度对JWEB50引发St本体聚合速率的影响.结果表明,温度升高10℃,聚合速率增大到原米的2～2 5倍;聚合速率与过氧键浓度的1/2次方成正比,为偶合终止.与单官能度引发剂过氧化2...     

采用Grubbs催化剂的双环戊二烯开环移位聚合速率调控

以双环戊二烯的反应注塑成型工艺为目的,研究了采用Grubbs催化剂的双环戊二烯开环移位聚合速率调控手段,详细考察了反应气氛、聚合温度、催化剂浓度及调聚剂三苯基膦含量对聚合过程的影响.结果表明,该体系可在少量氧存在的条件下聚合.即使反应温度较低( 35℃),凝胶时间仍可小于10min,且单体转化率接近100％.催化剂浓度...     

聚丁二酸丁二醇酯和聚间(对)苯二甲酰己二胺反应共混物的结晶行为

将聚丁二酸二醇酯(PBS)和无定形尼龙聚间(对)苯二甲酰已二胺(PA6IcoT)加入卧式反应釜中于260℃下进行熔融反应共混,利用超导核磁共振波谱仪((13)C-NMR)对产物进行结构表征,并采用差示扫描量热法分析其结品行为.结果表明:PBS和PA6IcoT物理共混时,PA6IcoT会阻碍PBS结晶,导致结晶活化能上升...     

粉煤灰微波合成沸石在水处理中的应用

以粉煤灰为原料采用微波水热合成法制备沸石,将其用于废水处理中,考察了粉煤灰合成沸石对氨氮、磷、Fe2+、Mn2+、Cu2+的去除效果.实验结果表明,与粉煤灰相比,粉煤灰合成沸石具有更高的氨氮、磷去除率;在吸附去除废水中的Fe2+、Mn2+、Cu2+时,合成沸石比天然沸石更有效.