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71.
超疏水多孔阵列碳纳米管薄膜 总被引:10,自引:1,他引:10
碳纳米管由于具有特异的力学[1] 、光学[2 ] 、电学[3,4 ] 和磁学性质[5] ,使其在锂离子电池[6 ] 和平板展示器[7] 等方面呈现出广泛的应用前景 .Ebbesen等[8] 对无序碳纳米管材料的浸润性进行了详细研究 ,发现其很容易被水润湿 .然而 ,阵列碳纳米管膜的浸润性研究尚未见报道 .固体表面的浸润性主要由表面化学组分和几何结构两方面控制 .通常 ,加大表面粗糙度可以增强其浸润性 [9~ 16 ] .近来 ,超疏水表面 (即与水的接触角大于 1 5 0°的表面 )的研究显示了广泛的应用背景[13~ 16 ] .这种表面通常可由增加表面粗糙度和降低表面能来制备[1… 相似文献
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稀土有机螯合物发光研究进展 总被引:16,自引:5,他引:16
总结了稀土有机螯合物结构与发光性能的关系:配体最低三重态能级与稀土离子激发态能级的匹配是中心稀土离子能否发光的主要因素;螯合物结构的平面性和刚性是中心离子发光效率高低的重要因素;适宜的第二配体的加入一般导致螯合物分子刚性和稳定性增高,因而有利于能量的传递,致使中心离子发光效率增高,但也不能忽视第二配体加入所引起光能的吸收和能量传递过程的竞争;配体的耐热,耐辐射性是配合物能否作为材料的必要因素,自行设计,合成了5类25种新的有机配体及其相应的二元,三元稀土螯合物,研究了这些螯合物的配位性质,发光性能,发光与结构关系及发光机制。提出并发展了稀土离子发光和电子振动光谱作为配合物和生物分子结构探针的两种新的方法。将稀土-β-二酮的发光螯合物与树脂制成荧光塑料;利用铕和铽螯合物的发光和免疫反应,检测了体液中生物活性物质的含量,证实以稀土离子替代放射性同位素作为标记物,有希望替代放射免疫分析方法,成为常规的临床检验方法,利用Tb^3 荧光检测了植物中生长激素的含量。 相似文献
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Recently, the studies on the interaction of DNA with small molecules have been attracting much interest1-6. These researches not only gave the important information about thermodynamics and kinetics, but also can prompt the combination between the electrode substances and biomacromolecule with super catalysis and sensor character. It is of great significance in understanding energy conversion and metabolism in live body, biomolecular structure, various physical and chemical characters for e… 相似文献
77.
Bao Chun LIU Mei Zhen QU* Zuo Long YU Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu Nanjing University of Chemical Technology Nanjing 《中国化学快报》2001,(12)
Since the discovery in 19911, carbon nanotubes have been the subject of intensive research due to their extraordinary mechanical and electronic properties2-7. However, lack of sufficient amount of materials limited the study of the fundamental properties and development of more practical applications. It is highly desirable to have large quantities of pure nanotubes. To date, few methods have been developed for the production of high-quality tubes which can adapted to industrial production … 相似文献
78.
Hierarchical MoS2@TiO2 Heterojunctions for Enhanced Photocatalytic Performance and Electrocatalytic Hydrogen Evolution 下载免费PDF全文
Yu Dong Sheng‐You Chen Yi Lu Yu‐Xuan Xiao Jie Hu Si‐Ming Wu Dr. Zhao Deng Prof. Ge Tian Prof. Gang‐Gang Chang Prof. Jing Li Prof. Silvia Lenaerts Prof. Christoph Janiak Prof. Xiao‐Yu Yang Prof. Bao‐Lian Su 《化学:亚洲杂志》2018,13(12):1609-1615
Hierarchical MoS2@TiO2 heterojunctions were synthesized through a one‐step hydrothermal method by using protonic titanate nanosheets as the precursor. The TiO2 nanosheets prevent the aggregation of MoS2 and promote the carrier transfer efficiency, and thus enhance the photocatalytic and electrocatalytic activity of the nanostructured MoS2. The obtained MoS2@TiO2 has significantly enhanced photocatalytic activity in the degradation of rhodamine B (over 5.2 times compared with pure MoS2) and acetone (over 2.8 times compared with pure MoS2). MoS2@TiO2 is also beneficial for electrocatalytic hydrogen evolution (26 times compared with pure MoS2, based on the cathodic current density). This work offers a promising way to prevent the self‐aggregation of MoS2 and provides a new insight for the design of heterojunctions for materials with lattice mismatches. 相似文献
79.
Reversible SC‐SC Transformation involving [4+4] Cycloaddition of Anthracene: A Single‐Ion to Single‐Molecule Magnet and Yellow‐Green to Blue‐White Emission 下载免费PDF全文
Xin‐Da Huang Yan Xu Kun Fan Prof. Dr. Song‐Song Bao Prof. Dr. Mohamedally Kurmoo Prof. Dr. Li‐Min Zheng 《Angewandte Chemie (International ed. in English)》2018,57(28):8577-8581
In search of magneto‐optic materials, the mononuclear compounds LnIII(depma)(NO3)3(hmpa)2 (Ln=Dy, Gd) were synthesized. The anthracene moieties undergo [4+4] dimerization when irradiated at 365 nm without loss of crystallinity. The Dy compound switches from a single‐ion to a single‐molecule magnet with doubling of the spin reversal barrier energy and from yellow‐green to blue‐white emission. The dimerization is reversed by heating at 100 °C or partially on light irradiating at 254 nm. The results suggest that lanthanide phosphonates with anthracene are promising smart materials displaying synergistic magneto‐optic property. 相似文献
80.
Guibin Yao Yuwei Fang Enyi Chi Jinbiao Bao Li Zhang Yiguo Li Jianqiang Zhang Zongbao Wang 《Polymer Science Series A》2018,60(5):663-670
Isotactic polypropylene (iPP)/reduced graphene oxide (RGO) nanocomposite bars were prepared by injection molding and the effects of RGO on the iPP matrix were investigated via differential scanning calorimetry, two dimensional wide angle X-ray diffraction (2D WAXD) and small angle X-ray scattering (2D SAXS) techniques. It is demonstrated that RGO is an effective nucleation agent for iPP and the incorporation of RGO can enhance the degree of orientation of iPP crystals at flow direction. Furthermore, the orientation of iPP chains at flow direction intensifies with the increase of RGO contents, which can be attributed to that RGO obstructed the motion of orientated polymer chains. Although the enhancement effect is weaker than that of High density polyethylene (HDPE)/RGO nanocomposites with epitaxial crystallization, the mechanical properties of iPP/RGO nanocomposites can also be improved apparently. 相似文献