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991.
Hisanori Shinohar 《中国颗粒学报》2004,(5)
Introduction C80 and C80-based endohedral metallofullerenes (named as Mn@C80 hereafter) have attracted extensive attention due to their special properties. C80 has an extremely low abundance in soot produced by arc discharge and it is only until recently that two isomers of C80(D2) were isolated by Kappes (Hennrich et al., 1996) and us (Wang et al., 2000). In contrast, some Mn@C80 have a relatively high abun-dance and so far the isolation of Mn@C80 has been achieved for both dimetallofull… 相似文献
992.
Preparation of porous α-Fe2O3-supported Pt and its sensing performance to volatile organic compounds
Yuhong Cheng Yanfei Kang Liwei Wang Yao Wang Shurong Wang Yujin Li Wei Zhong Liangqun Peng . TKL of Metal- Molecule-Based Material Chemistry and 《天然气化学杂志》2012,(1):11-16
Porous α-Fe2O3 was synthesized by a simple hydrothermal treatment of FeCl3 aqueous solution followed by a calcination process. In the synthesis of porous α-Fe2O3, no templates or pore-directing agents were used. The as-prepared porous α-Fe2O3 was further employed as a support for loading Pt nanoparticles. The gas sensing performance of the obtained porous α-Fe2O3-supported Pt to VOCs was investigated. The sensor presented a high response and fast response-recovery characteristic to several VOCs including acetone, ether, methanol, ethanol, butanol and hexanol. Meanwhile, it exhibited a much higher response than the pure α-Fe2O3 at the operating temperature of 260°C. The enhanced sensing properties may be related to the unique porous structure of the α-Fe2O3 support and the promoting effect of active Pt nanoparticles for the sensing reactions. 相似文献
993.
微波辅助溶剂提取法对土壤中残留苯并咪唑类农药的测定 总被引:11,自引:0,他引:11
报道了微波辅助溶剂提取、液 液分配净化、反相液相色谱 荧光法测定土壤中苯并咪唑类农药多菌灵、噻菌灵残留量的方法。对微波辅助溶剂提取的功率、时间、提取溶剂等操作条件进行了研究。以2mol LNH4Cl溶液、乙醇为提取液,在240W微波功率,提取时间1min的优化操作条件下,方法的回收率为89%~99%,相对标准偏差为3%~10%,方法的最低检出质量浓度多菌灵为3 63×10-4mg L,噻菌灵为5.20×10-5mg L,最小检出量多菌灵为1.21×10-11g,噻菌灵为1.74×10-12g。 相似文献
994.
CdS nanowires-nitrogen doped graphene(CdS NWs-NGR) nanocomposites have been fabricated by an electrostatic self-assembly strategy followed by a hydrothermal reduction. The CdS NWs-NGR exhibits higher photoactivity for selective reduction of aromatic nitro organics in water under visible light irradiation than blank CdS nanowires(CdS NWs) and CdS nanowires-reduced graphene oxide(CdS NWs-RGO)nanocomposites. The enhanced photoactivity of CdS NWs-NGR can be attributed to the improved electronic conductivity due to the introduction of nitrogen atoms, which thus enhances the separation and transfer of charge carriers photogenerated from CdS NWs.Our work could provide a facile method to synthesize NGR based one-dimensional(1D) semiconductor composites for selective organic transformations, and broaden the potential applications for NGR as a cocatalyst. 相似文献
995.
蔡子葵 《应用数学与计算数学学报》2004,18(1):63-66
本文运用数理统计原理建立版本相近性数学表达式,为揭示李商隐诗集版本的文字差异程度与亲疏关系,开创了一种定量分析方法。 相似文献
996.
JianQiangLIU QiZhenZHANG JingZhiZHANG 《中国化学快报》2004,15(12):1423-1426
The synthesis and characterization of two new star-like liquid crystals are reported. They are made of a silicon core and four alkoxyazobenzene monomers in the periphery. Theirp hase behaviors and the structures are determined by infrared absorption spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), elemental analysis (EA), polarizing optical microscope (POM) and differential scanning calorimetry (DSC). 相似文献
997.
ZeJiangZHANG XiuJuanMEI LiangRongFEN ShaoJieLU FaLiQIU 《中国化学快报》2004,15(7):867-870
Using nanocrystalline [Mg-Al-CO3] and [Zn-Al-CO3] as precursors, [Mg-Al-PO4],[Zn-Al-PO4], [Mg-Al-P2O7] and [Zn-Al-P2O7] have been successfully synthesized by a direct reaction with the free PO4^3- or P2O7^4- using the microwave techniques and the anion-exchange method. And the samples thus obtained were characterized by TEM, FT-IR and XRD. The results show that the initial interlayer carbonate ions can be completely replaced by the free PO4^3- or P2O7^4- under controlled microwave conditions employed for a short time. 相似文献
998.
正交型光热偏转光谱法及其差分构型研究 总被引:1,自引:1,他引:0
本工作设计了一种新的差分式光热偏转光路构型,光路的优点是只使用单一的位置传感器,可随意调节样品池和参考池的距离,电学补偿和差分光路装置简单,容易调整,可以有效地消除溶剂空白吸收的影响和泵浦激光功率起伏的影响。文章还讨论了该差分构型的原理,差分响应公式和基本实验参数。获得的结晶紫和钴的检测下限分别为8.0×10^-10mol/L和60mg/ml,对应的最小吸光度分别为1.2×10^-8和5.4×10 相似文献
999.
利用红外二向色性研究了聚脲氨酯中软、硬段及界面层的取向行为。证明了软、硬段处于完全不同的结构形态中。在较低拉伸水平时,硬段主要垂直于拉伸方向取向;在较高拉伸水平时,则转到沿拉伸方向取向。软段和界面则始终沿拉伸方向取向。 相似文献
1000.
2-Amino-2-chromenes are class of heterocycles that posses considerable interest as pigments,cosmetics,potential agrochemicals and being the main constituents of many natural products.Although,they are generally prepared either under conventional heating,benign reagents or very recently,a three component condensation in poly-ethylene glycol-water in the presence of nanosized magnesium oxide,most of these methods require prolonged reaction time,reagents in stoichiometric amounts and generate moderate yield... 相似文献