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181.
有机-无机纳米复合材料的研究在当前纳米科学技术的发展中占有重要地位,开创了材料与催化科学研究的新纪元。自从10年前首次合成纳米孔无机材料MCM-41至今,该领域研究不断深入,已展现出广阔的应用前景。当客体有机分子分散于纳米孔道内部时,其分子性质将产生明显变化。本文结合作者近期研究成果,力图从实验与理论两方面阐明在纳米复合体系中客体分子性质变化的原因。 相似文献
182.
本文报道由H2PDC合成的新型维层状无机-有机骨架晶体Ni(PDC)(H2O)2(H2PDC=吡啶-2,5-二羧酸), 该化合物的一层是由右手螺旋Ni—O—C链与左手螺旋Ni-pdc链组成, 而邻近的一层则是由左手螺旋Ni—O—C链与右手螺旋Ni-pdc链组成, 层与层之间通过氢键作用形成了三维超分子结构. 用ICP、TG、IR和X射线单晶衍射分析等手段对其结构进行表征. 相似文献
183.
The composite material of polyaniline/NiO/sodium dodecylbenzenesulfonate (SDBS) is synthesized in SDBS micelles. The composite material has satisfactory conductivity and thermostability, and the particle length, width, and thickness are about 200–500 m, 3–5 m, and 40–96 nm, respectively. 相似文献
184.
Peter Schramel 《Mikrochimica acta》1989,99(3-6):355-364
The most sensitive emission lines for the elements B, Be, Co and Mo are strongly influenced by disturbing emission lines of Fe using normal optical resolution. The advantages of high resolution, applying the new ICP-spectrometer JY 38 Plus (Jobin-Yvon, France) with the 2400 lines/mm grating measuring in the 1st and 2nd order will be discussed. Beside the concentrations in soils, sediments and sludges, applying aqua regia and HF decomposition methods, the detection limits in these matrices will be given. The possibilities of ICP-spectrometry for the determination of the above-mentioned elements are shown at the examples of SRMs (standard reference materials). The materials used here were three soils and three sludges from the BCR (Community Bureau of Reference, European Communities) and one sediment from NBS (National Bureau of Standards, USA). For example, the most sensitive and normally used line for the determination of boron at 249.7733 nm cannot be used in case of this type of matrix due to normally high Fe-concentrations and due to a strong Fe-interference. Therefore, it is necessary to use the line at 249.6778 nm, where an interference-free measurement can be achieved in case of high optical resolution. The measured B-contents in these samples are in the range of 20 to 60 g/g, for Co in the 10 g/g region, for Be well below 1 g/g, for Sn between 3 and 400 g/g. Mo was only detectable in the sludge samples (limit of determination 0.5 g/g).Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria 相似文献
185.
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186.
一种新型吡嗪铱(Ⅲ)配合物的合成及其磷光性质 总被引:2,自引:0,他引:2
利用5-甲基-2,3-二苯基吡嗪(MDPP)和水合三氯化铱(IrCl3•H2O),合成了一种新型吡嗪铱配合物Ir (MDPP)2 (acac).通过1H NMR、元素分析和质谱方法对配合物结构进行了表征,并研究了配合物的吸收光谱和光致发光光谱.结果表明,配合物Ir (MDPP)2(acac)在393和528 nm处存在单重态1MLCT(金属到配体的电荷跃迁)和三重态3MLCT的吸收;在588 nm 处有较强的金属配合物三重态的磷光发射,是一种绿色磷光材料. 相似文献
187.
Shingo KomatsuYouichi Sakamoto Toshiyasu Suzuki Shizuo Tokito 《Journal of solid state chemistry》2002,168(2):470-473
Perfluoro-1,3,5-tris(p-quaterphenyl)benzene (PF-13Y) and perfluoro-1,3,5-tris(p-quinquephenyl)benzene (PF-16Y) have been synthesized and characterized. They showed higher glass transition temperatures compared with perfluoro-1,3,5-tris(p-terphenyl)benzene (PF-10Y). Organic light-emitting diodes were fabricated using these materials as the electron-transport layers. PF-13Y and -16Y are better electron transporters than PF-10Y. The electron mobilities of PF-10Y and Alq3 were measured by the time-of-flight technique. PF-10Y showed higher electron mobilities (10−4 cm2/V s) and weaker electric field dependence compared with Alq3. 相似文献
188.
A method is described for the simultaneous quantitative determination of monoamines and related compounds from urine and brain tissue samples in the pg-range, using a GC/MF instrument LKB-2091 provided with a multiple ion detection (MID) system and capillary columns. The simultaneous detection of “fingerprints” with fourteen and more compounds during one single GC run was achieved after the intoduction of “time gates” for the detection of the different characteristic masses. Several modifications to the LKB equipment permitted exact reproducibility of retention times, which is essential for the use of “time gates”. The detection of “fingerprints” with these acidic, basic and alcoholic substances was achieved by the extraction of the dried biological samples with silylating agents. 相似文献
189.
CrystalStructureof[Cd(pom)_2Cl_2]WuWen-Shi(DepartmentofChemistry,Hua-qiaoUniversity,Fujian,China,362011)DongMei-Bin;LiSong-Xia... 相似文献
190.
Pil Kim Younghun Kim Taewook Kang In Kyu Song Jongheop Yi 《Catalysis Surveys from Asia》2007,11(1-2):49-58
Mesoporous materials have attracted considerable attention for use as a catalyst or a catalyst support due to their remarkable
textural properties such as high surface area and large pore volume with a narrow pore size distribution. Many efforts have
been made to design mesoporous materials for use in heterogeneous catalyst systems. Recent progress and results regarding
the preparation of nickel-mesoporous materials and their application to the hydrodechlorination of chlorinated organic compounds
were discussed in this review. Mesoporous materials were used as a support for nickel catalyst or a nickel-incorporated mesoporous
catalytic material in this work. Two research areas were described and discussed in this review. One is the preparation of
mesoporous alumina-supported nickel catalysts and their application to the hydrodechlorination of 1,2-dichloropropane and
o-dichlorobenzene. The other is the preparation of mesoporous silica-supported nickel catalysts and their application to the
hydrodechlorination of 1,1,2-trichloroethane and chlorobenzene. 相似文献