Carbon nanotube–polyaniline composites

The last decade has seen a growing interest in hybrid electrically conducting nanocomposites. This article aims to provide a detailed overview of the present status of research in carbon nanotube–polyaniline (CNT/PANI) composites, from processing to structural and property evaluations. CNT/PANI are synthesized by electrochemical and chemical processing. When chemical methods are used, the main challenge is to obtain processable CNT/PANI in the emeraldine salt (ES) form composites. Stable dispersions of ES–CNT in organic media are prepared using the post doping method, inverse emulsion polymerization, or ex situ polymerizations. On the contrary, stable water dispersions of CNT/ES are prepared using hydrophilization of a preformed CNT/ES composite, direct synthesis of micelle–CNT hybrid templates, interfacial polymerization, covalent functionalization of CNT with a water soluble polymer, or using electrostatic interactions between two oppositely charged ES and CNT aqueous colloids. Moreover, the strategies for the synthesis of ternary CNT/PANI composites incorporating noble metal nanoparticles, metal oxide, or graphene sheets are also presented and analyzed in depth. Finally, we give a review of potential applications, including chemical sensors, capacitors, fuel cells and electronic devices.     

Fe/Bi0.5Sb1.5Te3热电元件高温稳定性研究

热电元件的界面高温稳定性是决定热电器件服役性能和应用前景的重要因素,而阻挡层和热电材料之间的界面扩散和界面电阻则是评价热电元件高温稳定性的主要标准.为了进一步提升P型碲化铋热电器件的界面稳定性,本研究采用高通量筛选的方法选定适用于P型碲化铋的Fe阻挡层材料.通过一步烧结的方法制备了Fe/P-BT的热电元件,并系统研究了...     

聚苯硫醚/聚砜反应性共混物的增韧机理研究

以环氧树脂(EP)为界面反应剂,通过熔融共混制备了聚苯硫醚(PPS)/聚砜(PSU)/EP共混合金,考察了合金的流变行为、力学性能、相形态及增韧机理。结果表明,在PPS/PSU中加入EP后,基体间的相容性得到提高;当EP含量为5%时,力学性能最优;该共混合金的增韧机理为分散相引发银纹机理。     

NBR-PF-TDI-ATH的表面性质及其与PVC的界面特性

采用表面原位化学组合改性的方法,在Al(OH)3(ATH)表面顺序经原位化学反应结合上甲苯二异氰酸酯(TDI)、烷基酚醛树脂(PF)、丁腈橡胶(NBR)等界面改性剂。通过接触角测量、表面张力及其与PVC界面张力的计算结果表明,TDI、PF、NBR依次在ATH表面成功地形成了极性由大到小、逐步过渡的多层改性层,ATH表面极性随着改性层数的增加而逐步减小。与未改性的ATH相比,改性ATH的表面极性减小,其表面张力及其与PVC的界面张力均明显下降,填充PVC复合材料的力学性能提高。界面特征的理论计算表明,其脆韧转变符合逾渗模型。本方法对ATH的处理效果胜过偶联剂。     

波纹辊和平辊轧制Ti/Cu/Ti层压复合材料的显微组织与力学性能（英文）

采用波纹辊和平辊轧制方法制备钛/铜/钛(Ti/Cu/Ti)层压复合板材料。通过扫描电镜、数值模拟、剥离和拉伸实验等方法研究层压复合板的显微组织和力学性能,对比分析波纹辊和平辊轧制效果。结果表明：波纹辊和平辊轧制的层压复合板在Ti层和Cu层界面处表现出不同的有效塑性应变分布。波纹辊轧制的层压复合板中,Ti层具有再结晶织构、棱柱面织构和棱锥面织构,Cu层形成高斯织构和剪切织构;而平辊轧制的层压复合板中,Ti层和Cu层均具有典型的变形织构。波纹辊轧制的层压复合板材料具有较高的结合强度、抗拉强度和延展性。     

纤维布混杂形式对混凝土界面力学性能的影响

针对CFS-GFS混杂加固钢筋混凝土梁的一种新型加固方法,通过建立不同材料本构方程,对8种不同加固模型做了非线性界面有限元数值计算.分析了不同加固形式下界面端部剪应力与正应力的分布规律,结果表明界面剪应力与正应力极大值均出现在加固界面端部,且在较短的距离内迅速减小.CFS-GFS混杂加固可以有效降低界面剥离应力,通过控制GFS在加固中所占比例,能够在保证承载力足够的情况下,改善加固界面力学性能,避免端部处发生界面或保护层剥离破坏现象.     

硬脂酸修饰Lipolase脂肪酶的性能

采用N-羟基琥珀酰亚胺活化法用硬脂酸对Lipolase脂肪酶进行了化学修饰。研究了Lipolase脂肪酶的水解活力和酯化活力,重点研究了界面催化活性和表/界面张力。实验结果表明:与未修饰酶相比,修饰Lipolase的水解活力略有下降,但正己烷中的酯化活力和界面水解活力均明显提高;修饰Lipolase降低表面张力与界面张力的能力提高。用LB技术制备Lipolase的单分子层膜,发现修饰Lipolase的∏-A曲线上移,表明修饰Lipolase更易在表面形成单分子层膜。可见Lipolase脂肪酶经硬脂酸修饰后界面活性提高、有利于在有机相或两相界面催化化学反应。     

液相烧结钨合金快冷增韧的俄歇分析

用扫描俄歇探针 ( SAM)结合工艺试验研究了烧结态和经真空热处理的 95W-Ni-Fe合金冷却速度对其性能的影响。结果表明 ,磷是引起该合金界面脆化的重要因素 ;快冷可以明显抑制磷的界面偏聚 ,有效提高该合金的延性和韧性。     

Code performance with improved two-group interfacial area concentration correlation for one-dimensional forced convective two-phase flow simulation

In gas–liquid two-phase flow simulation for reactor safety analysis, interfacial momentum transfer in two-fluid model plays an important role in predicting void fraction. Depending on flow conditions, a shape of the two-phase interface complicatedly evolves. One of the proposed approaches is to quantify the gas–liquid interface information using interfacial area transport equation. On the other hand, a more simplified and robust approach is to classify bubbles into two-groups based on their transport characteristics and utilize constitutive equations for interfacial area concentration for each group. In this paper, interfacial drag model based on the two-group interfacial area concentration correlations is implemented into system analysis code, and void fractions were calculated for the evaluation of numerical behaviors. The present analysis includes (1) comparison of one-group and two-group relative velocity models, (2) comparison with separate effect test database, (3) uncertainty evaluation of drag coefficient, (4) numerical stability assessment in flow regime transition, and (5) transient analysis for simulating the prototypic condition. Results showed that utilization of interfacial drag force term using constitutive equations of two-group interfacial area concentration yields satisfactory void fraction calculation results. The proposed solution technique is practical and advantageous in view of reducing the computational cost and simplifying the solution scheme.