Microwave absorbing properties of polyaniline/montmorillonite doped with dodecylbenzensulfonic acid nanocomposite

In this paper, we reported a new type of high performance microwave-absorbing material, polyaniline/montmorillonite doped with dodecylbenzensulfonic acid (PAni-DBSA/MMT) nanocomposite. The microwave-absorbing properties of this nanocomposite were investigated for the frist time. The nanocomposites were synthesized from emulsion polymerization using dodecylbenzensulfonic acid (DBSA) as dopant and emulsifier. The structure of the nanocomposite was analyzed by X-ray diffraction(XRD) and FT-IR, and its results denoted that PAni-DBSA/MMT is a typical intercalative polymer/layered silicate(PLS) nanocomposite, and the interaction between MMT layers and PAni chains enhances the delocalization of free electrons in PAni chains. The complex permittivity, permeability and reflection loss (R.L.) of microwave of a 2.00 mm thick samples containing 50% by weight of PAni-DBSA/MMT nanocomposite and PANI?DBSA were measured, respectively, in 2?18 GHz range. The results showed that the PANI-DBSA/MMT nanocomposite is capable of absorbing 2.0?18 GHz microwaves, and the reflection loss was less than -10 dB in the frequency range of 9.1?12.5 GHz, while the minimum reflection loss was -15.8 dB at 11 GHz. The microwave absorbing mechanism of nanocomposite is disscused.     

功率梯度热障涂层热震裂纹的形成的扩展

探索热弹涂层在热震中裂纹的形成规律，揭示涂层热震危险截面位置，采用在铝基体上以等离子喷涂法制备Al/Ni-ZrO2功能梯度涂层，在所研制的热性能测试仪上，用单面加热急冷法，观察不同热循环次数下的裂纹形成情况，结果是热震15次时首先在纯ZrO2与ZrO2与Al/Ni质量比为8：2的界面上方产生水平裂纹，50次时出现龟裂纹，热震裂纹出现的最危险截面在上述界面上方大约80μm处，此处热应力最大。     

剪切场下聚丙烯柱晶的形成与机理研究回顾

分析、对比、讨论了聚丙烯及其弹性体共混体系和纳米粘土复合材料体系在剪切场中的柱晶形成形貌和机理.对近期所作的剪切诱导结晶工作进行了回顾与总结.剪切场下缠结的高分子链被拉伸并形成柱晶的晶核是剪切诱导结晶的首要条件,柱晶的形貌受材料体系、相分离过程、纳米填料的介观网络结构形成与分散状况及剪切条件的影响.     

介孔结构Na4W10O32/TiO2复合光催化剂的制备及其可见光光催化性能的研究

用溶胶-凝胶和程序升温水热法制备了介孔结构的Na4W10O32/TiO2多酸纳米晶复合光催化剂.用ICP-AES、XRD、拉曼散射光谱、TEM和N2吸附测定等技术对其组成和结构进行了表征.考察了催化剂的可见光光催化性能.结果表明:Na4W10O32均匀地分散在TiO2网络内部,而且其基本骨架结构未发生改变;该催化剂比锐钛矿TiO2,H6P2W18O62/TiO2和H4SiW12O40/TiO2具有更高的可见光光催化活性.     

辐射水凝胶法制备金属—聚合物纳米复合材料

利用水凝胶的高吸水性和内部交联网络提供的纳米空间,并利用γ－射线产生的还原性粒子（H.和e^-aq)来还原被吸进P（AA／DMMC）水凝胶中的银离子以及PAM水凝胶中的银离子和二价铜离子,制得Ag-P(AA/DMMC),Ag-PAM和Cu2O-PAM纳米复合材料,TEM分析表明,银原子在P（AA／DMMC）和在PAM凝胶网络内都聚集成纳米粒子,且粒径分布很窄,银粒子在凝胶中分布均匀,XRD分析表明,纳米银在非离子在离子型水凝胶聚（AA／DMMC）中,银粒子的晶型受络合剂的影响,不加为非晶,反之为立方晶型,XRD和TEM分析也表明：复合在PAM中的Cu2O粒子为纳米晶体。     

Preparation and Structure of Poly （ethylene- co-vinylacetate）/Montmorillonite Nanocomposites

Poly(ethylene-co-vinylacetate)/sodium montmorillonite (EVA/MMT) and Poly (ethylene-co-vinylacetate)/arganophilic montmorillonite (EVA/o-MMT) nanocomposite were prepared by solid-state mixing. The morphology and structure of the composites were explored by scanning electron microscopy (SEM),wide-angle X-ray diffraction (WAXD ), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA).The results showed that the intercalated nanocomposite was successfully synthesized for EVA/o-MMT system, while in the EVA/MMT nanocomposite, MMT were poorly dispersed in the order of urn. An unexpected rubbery plateau modulus of EVA/o-MMT nanocomposite above melting point of EVA was explored by DMA. The possible origins of this high-temperature modulus were analyzed.     

Ti或TiN的添加对MoS2基复合薄膜耐磨性能的影响

为改进纯MoS2薄膜在大气环境下极易氧化失效且耐磨损性能较差的缺点,采用非平衡纳米复合等离子体镀膜技术合成了MoS2基薄膜, 该薄膜由Ti或TiN与MoS2共沉积而成.采用扫描电子显微镜、干钻削和车削实验确定薄膜的结构、成份和机械性能.结果显示, 在潮湿和超低温环境下,薄膜具有优异的耐磨寿命和抗氧化性.实验表明, 改进后的MoS2基复合薄膜在机加和成型等领域中具有广泛的应用前景.     

聚苯胺纳米复合材料用于癌症诊疗的研究进展

共轭聚合物以其独特的结构和性能得到了广泛的关注.聚苯胺（PANI）纳米复合材料制备工艺简单、成本低廉、毒性低、易于功能化,从而在癌症治疗方面取得了巨大的进展.通过不同功能的化合物修饰制备的PANI纳米复合材料极大地拓宽了癌症治疗领域.基于PANI纳米复合材料,文章总结了其在癌症诊疗领域的光热治疗、协同治疗、多模态成像引导治疗和智能响应治疗的研究进展,并分析了其发展趋势.     

表层沉积物和生物膜对双酚A的非线性吸附

以松花江表层沉积物和生物膜为例, 建立液相色谱法 快速检测水中双酚A（BPA), 并研究了BPA在表层沉积物(SSs)和生物膜(NSCSs)上的吸附规律. 结果表明, 采用液相色谱法, 配以紫外检测器, 对BPA的检测限（MDLs）为10 μg/L, 相对标准偏差（RSD）为2.6%~5.7%, 加标回收率为99.4%~117.8%（n=5）. 吸附实验结果表明, BPA在松花江表层沉积物和生物膜上的吸附过程主要为非线性吸附, Freundlich和Langmuir等温线均可描述BPA在表层沉积物和生物膜样品上的热力学吸附过程（p=0.001,n=8）. 与表层沉积物相比, 生物膜有机质含量较高, 具有较强的吸附能力.