Conductive polyaniline–polythiophene/poly(ethylene terephthalate) composite fiber: Effects of pH and washing processes on surface resistivity

A conductive polyaniline (PAn)–polythiophene (PTh)/poly(ethylene terephthalate) (PET) composite fiber was prepared by polymerization of aniline and thiophene in the presence of PET fibers in an organic medium with FeCl₃. The effects of polymerization conditions, such as polymerization medium, mol ratios of aniline/thiophene and FeCl₃/aniline‐thiophene as well as polymerization temperature and time, were investigated on PAn–PTh content (%) and surface resistivity of the composite. The composite with the lowest surface resistivity (1.30 MΩ/cm²) was obtained by polymerization of aniline and thiophene (1/3 mol ratio) in acetonitrile/chloroform (1/5 volume ratio) at 20°C. The surface resistivity of the PAn–PTh/PET composite containing 4.8% PAn–PTh was increased from 1.9 MΩ/cm² to 270 MΩ/cm² at pH 11. The washing durability of the composites was determined with domestic and commercial laundering processes by monitoring the surface resistivity and morphology. The composite was also characterized with FTIR, TGA, elemental analysis, optic microscope and SEM techniques. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41979.     

钢管混凝土X形交叉柱轴压性能研究

为研究圆形和长圆形截面钢管混凝土柱交叉相贯形成的变截面不规则钢管混凝土组合柱,即钢管混凝土X形柱的轴压性能,采用有限元软件ABAQUS建立上述两种截面钢管混凝土X形柱的轴压模型,并通过与试验结果对比验证有限元模型的合理性,在此基础上,对圆形和长圆形截面钢管混凝土X形柱的受力全过程进行分析,并对钢管混凝土X形柱进行参数分析。研究表明,钢管混凝土X形柱在节点交叉区域钢管对混凝土产生不均匀的约束作用,混凝土中心区域受到的约束作用最大,其次是左右区域,钢管相交部位的混凝土受到约束最小,部分截面甚至在混凝土与钢管之间发生脱离。随着混凝土强度提高、钢材强度提高、钢管壁厚增加以及交叉角度加大,钢管混凝土X形柱的轴压承载力相应提高。     

合成气压缩机浮环密封油压力降低的原因及其处理

合成气压缩机参考气管线进油,运行中油气压差持续降低,一直降到油气压差平衡,压差表显示为零,严重影响正常生产。针对此问题进行原因分析,提出处理措施。     

气相色谱-质谱法检测喷胶中卤代烃及烷烃含量

以正十一烷为内标物,采用气相色谱-质谱(GC-MS)法建立了喷胶中卤代烃及烷烃含量的检测方法。研究结果表明:各目标化合物的校正曲线在浓度为5~400μg/mL范围内呈良好的线性关系,其线性相关系数均超过0.999 0,平均回收率为89.06%~103.36%,相对标准偏差(RSD)为0.97%~4.13%;该方法具有良好的重现性和较高的灵敏度,在部分市售喷胶中进行验证时,所得结果令人满意。     

Identification of Novel CERT Ligands as Potential Ceramide Trafficking Inhibitors

A highly compartmentalized enzymatic network regulates the pro‐apoptotic and proliferative effects of sphingolipids. Over‐conversion of ceramide (Cer) correlates with insensitivity to apoptosis signaling (in response to chemotherapy) and to drug resistance of cancer cells. De novo sphingomyelin biosynthesis relies on non‐vesicular ceramide trafficking by the CERT (CERamide Transfer) protein. Therefore, blocking CERT transfer, thus leading to increased intracellular ceramide availability, represents a potential anticancer strategy. Our study is based on the implementation of an in vitro binding assay, supported by in silico molecular docking. It constitutes the first attempt to explore at the molecular level for the identification of novel CERT ligands. This approach is the first step toward in silico design and optimization of CERT inhibitor candidates, potentially relevant as innovative ceramide‐transfer‐targeting therapeutic agents.     

NaOH改性MnO2/γ-Al2O3催化尿素醇解合成碳酸丙烯酯

采用超声浸渍法制备了MnO₂/γ-Al₂O₃催化剂,并用碱和盐对其进行了改性.采用X射线衍射仪(XRD)、CO₂-TPD对改性后的MnO₂/γ-Al₂O₃催化剂进行了表征,研究了改性后催化剂在尿素醇解合成碳酸丙烯酯(PC)反应中的催化性能.研究结果表明,NaOH改性MnO₂/γ-Al₂O₃催化剂具有最好的催化性能;同时催化剂的焙烧时间、焙烧温度以及NaOH改性量影响催化剂表面碱性活性中心的数量和强度,其中中强碱的增加是改性后催化剂活性提高的主要原因.在NaOH用量为MnO₂质量的10%,400℃焙烧2h后,改性MnO₂/γ-Al₂O₃催化剂表面的中强碱量最大,催化活性最高,PC收率与选择性分别达86.9%、91.8%.     

烧结工序流分析及评价

在钢铁形势日趋严峻的当下,节能减排是烧结厂得以生存的必由之路。基于物料平衡和热平衡原理建立的烧结工序流评价模型,可以从宏观和微观两方面反映出烧结工序的流走向,从而挖掘其节能潜力所在。对某一典型烧结厂的流分析研究结果表明,该烧结过程固体燃料和混合料的分别占收入的73.59%和17.28%,热烧结矿的物理、烧结机损和烟气的热量分别占支出的47.42%、30.34%和21.63%,该烧结工艺的普遍效率和目的效率分别为69.66%和48.02%,具有较大的节能潜力。可以采用优化配矿、厚料层烧结、烟气循环烧结、余热发电等技术措施来提高效率,最终实现烧结工序节能减排的目的。     

‘Green’ synthesis and optical properties of silver–chitosan complexes and nanocomposites

Silver nanoparticles were synthesized in a chitosan biopolymer by an in situ ‘green’ chemical procedure, using d-glucose as the reducing agent. The reaction intermediates (silver–chitosan complexes) as well as the obtained nanocomposites were investigated using transmission electron microscopy, UV–vis, FTIR and photoluminescence spectroscopy. The theoretical analysis of the UV–vis absorption of the Ag–chitosan complexes suggested that the significant contribution to the complex spectrum arises from clusters of silver containing 4–9 atoms. The absorption spectrum of the nanocomposite exhibited a strong surface plasmon resonance band at 406 nm. The photoluminescence behavior of the pure chitosan, the silver–chitosan complexes and the nanocomposites were discussed in terms of morphology and silver weight content.     

一种微型万向平台的姿态控制

针对一种微型万向平台,介绍了其构成情况、工作原理及典型应用。通过建立的几何模型,分析了其姿态控制方法。阐述并分析了Preisach迟滞模型并进行了数字仿真。结果表明采用Preisach模型的迟滞补偿方法对该微型万向平台的SMA进行驱动时,可有效提高控制响应;该方法可较容易地预测经过任意序列输入参数以后的输出情况。