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41.
Platinum nanoclusters were deposited along the supercoiled DNA strands after incubation of cis-(trans-1R,2R-diaminocyclohexane)(dl-camphorato)platinum(Ⅱ) (Cdp), an analogue of the anti-tumor drug-carboplatin, with DNA and K2PtCl4 for 600 min and then through reduction of dimethylaminoborane (DMAB). The decrease of absorption of DNA at 260 nm indicates the coordination of Cdp and DNA. TEM and AFM were employed to characterize the morphologies and structures of platinum nanoclusters. 相似文献
42.
43.
Ilaria Fratoddi Maurizio Delfini Michael B. Hursthouse Maria V. Russo 《Journal of organometallic chemistry》2006,691(26):5920-5926
The synthesis and characterization of a tetranuclear Pt complex, cis-trans-cis-trans tetra[μ-2,6-diethynyl-4-nitroaniline-bis(tri(p-tolyl)phosphine) platinum(II)], namely [L2Pt-DENA]4 with L = tri-p-tolylphosphine, is reported. The complex was obtained by the dehydrohalogenative condensation of 2,6-diethynyl-4-nitroaniline (DENA) with cis-[dichlorobis(tri(p-tolyl)phosphine)platinum(II)]. The single crystal structure determination of [L2Pt-DENA]4 indicated the formation of a neutral molecular cycle with four alternating platinum units in cis and trans configurations, all bridged with DENA spacers with the presence of solvent (toluene) crystallization molecules. A twisted tetranuclear cyclic feature was identified. The formation of intermolecular stacks of the tetranuclear complex in solution was assessed by means of nuclear Overhauser enhancement spectroscopy (NOESY) and rotating frame Overhauser effect spectroscopy (ROESY) characterizations. 相似文献
44.
贵金属对钴基催化剂上肉桂醛选择加氢反应的影响 总被引:5,自引:0,他引:5
研究了贵金属改性的Co/γ-Al2O3催化剂上的肉桂醛选择加氢反应.结果表明,通过Pt,Pd和Ru贵金属改性,提高了催化剂的活性,但只有Pt改性的催化剂具有较高的选择性.w(Pt)<0.5%时,催化剂的活性随着Pt含量的增加呈直线升高,当w(Pt)=0.5%时,催化剂活性可提高近5倍,但催化剂的选择性变化很小.XRD结果表明,催化剂经还原后,γ-Al2O3上的钴主要为α-Co0.TPR结果表明,Pt的加入提高了Co3O4的还原性能,且Pt含量越高,Co3O4的还原温度越低.XPS结果表明,Pt改性的催化剂样品,其Co3O4大部分被还原为Co0.由于Pt与Co具有协同效应,故Pt改性的Co/γ-Al2O3催化剂既具有较高的活性,又具有很高的选择性. 相似文献
45.
A Contribution on Ba3Pt4HgO11: The First Alkaline-Earth Oxoplatinate(II,V)/Oxomercurate Single crystals of Ba3Pt4HgO11 were prepared by oxygen high pressure technique (4 200–3 600 bar) and investigated by X-ray methods. It crystallizes with hexagonal symmetry, space group D? P6 2c, a = 6.021, c = 17.374 Å, Z = 2. Ba3Pt4HgO11 represents a new structure type, showing structural relationships to Ba2Hg3Pd7O14 and to the precious metal 6L-perovskites. The Hg2+ ions show dumb-bell like coordination, Pt2+ a square-planar surrounding and Pt5+ face shared double octahedra. 相似文献
46.
Molecular switches that are controllable, reversible and readable at molecular level are an essential compo-nent of molecular electronics1 and chemical sensors.2-6 Of particular interest are the molecules which show dramatic and reversible changes in color and/or lumi-nescence in visible spectral region upon exposure to specific substrates. A number of chromophore- spacer-receptor systems that can selectively recognize specific guest molecules at their receptor site and pro-duce measurable col… 相似文献
47.
48.
Ruo Zhong WANG Lang Tao XIAO Ming Hui YANG Jun Hui DING Feng Li QU Guo Li-SHEN 《中国化学快报》2006,17(12):1585-1588
Platinum nanowire (PtNW) can be grown by electrodeposition in polycarbonate membrane, with the average diameter of the nanowires about 250 nm. The PtNW and multiwalled carbon nanotubes (CNT) are then dispersed into chitosan (CHIT) solution. The resulting PtNW-CNT-CHIT material brings new capabilities for electrochemical devices by using the synergistic action of the electrocatalytic activity of PtNW and CNT. By dropping the PtNW-CNT-CHIT film onto the glassy carbon (GO) electrode surface, and after evaporation an amperometric sensor for the determination of indole-3-acetic acid (IAA) was developed. The oxidation current of IAA increased significantly at the PtNW-CNT-CHIT film coated GC electrode, in contrast to that at the CNT-CHIT modified GC. The linear response of the sensor is from 50 ng/ml to 50 μg/ml with a detection limit of 25 ng/mL. 相似文献
49.
Introduction Luminescent coordinatively unsaturated platinum(II) complexes are appealing from photochemical and pho-tophysical perspective.1,2 In particular, platinum(II) ter-pyridyl complexes have attracted considerable attention due to their rich spectroscopic2a-d and biological proper-ties.2a,e-g However, the development of the photochem-istry of these complexes is limited by their short-lived MLCT excited state in solution at room temperature. The lack of emission originates from low-l… 相似文献
50.
Summary In the present study the effects of addition of iron on the catalytic activity and Si tolerability of Pt/g-Al2O3in the total oxidation of volatile organic compounds were investigated. Preliminary results showed that there is a noticeable
improvement effect on Si-tolerance of catalyst, particularly for short term poison exposure. Bulk analysis of deposited silicon
on the catalyst surface indicated that both Pt/g-Al2O3and iron-doped pellets had roughly the same silicone uptakes. Deactivation of catalyst was reversible and much faster for
iron doped sample. The promoting effects of iron were related to its electronegativity and, to blocking of fewer Pt sites
when iron is present at the surface of the catalyst. 相似文献