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1.
Ulf Pindur Ludwig Pfeuffer Manfred Eitel Martina Rogge Manfred Haber 《Monatshefte für Chemie / Chemical Monthly》1991,122(4):291-298
Summary Diels-Alder reactions of 2- and 3-vinylindoles with aryne, 1,4-benzo- and 1,4-naphtho-quinone lead to new six-ring annellated carbazoles. Molecular modeling studies predict that the compounds with coplanar framework are able to intercalate with the B-DNA. 相似文献
2.
Polymorphic transformations of CoMoO4 were studied by means of high temperature X-ray measurements within the temperature range 25–1200°C. On heating phase a obtained from low temperature modification b a new modification a′ was discovered. Phase a obtained by thermal decomposition of solvated α-CoMoO4 shows different behaviour. At 700–930°C depending on the conditions of preparation it transforms irreversibly into still another modification a″. On cooling, a mixture of phases a + a″ is obtained, the presence of a″ being responsible for the explosionwise transition into b, observed around the room temperature. 相似文献
3.
IR spectra of propylene and acrolein adsorbed at different temperatures on CoMoO4 supported on MgO were recorded. Four different surface species were found: a -complex, an oxygen bonded carbonyl complex, acrylic acid and a carboxylate type complex. The mechanism of their transoformation is discussed.
- CoMoO4 MgO. , 4 : -, , , . .相似文献
4.
Isaac Zigelboim Daniel Offen Eldad Melamed Hana Panet Moshe Rehavi Yoram Cohen 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(3-4):323-329
Although magnetic resonance imaging (MRI) is one of the most important imaging modalities of the central nervous system (CNS),
one of the main drawbacks of MRI is its limited specificity. This can potentially be partially alleviated by target-specific
contrast agents. In the present paper we describe a simple high yield synthesis of two such gadolinium-based spiperone targeted
MRI contrast agents, 1a and 1b. The R1 relaxivities of 1a and 1b were evaluated and found to be 5.94 and 8.31 mM−1 s−1, respectively at 9.4T, while their R2 relaxivities at the same magnetic field were found to be 18.05 and 22.60 mM−1 s−1, respectively. In addition and very importantly compound 1a, which is a gadolinium-based, spiperone-targeted MRI contrast agent, was found to preserve some of the spiperone affinity
toward the dopamine D2 receptor. Compounds 1a and 1b thus represent potential agents for in vitro dopamine receptor imaging using MRI in experimental models.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
Five different doublets corresponding to W 4f electrons were observed in the course of reduction of WO3. On contact of WO3 with hydrogen, W5+ ions are formed. Reduction results at first in formation of isolated W4+ ions. Clusters of edge-sharing octahedra on shear planes are then formed, in which pairing of W4+ ions occurs due to metal-metal bonding, corresponding to an apparent 2+ oxidation state. 相似文献
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We show that the semiclassical dynamics of an electronic droplet, confined in a plane in a quantizing inhomogeneous magnetic field in the regime where the electrostatic interaction is negligible, is similar to viscous (Saffman-Taylor) fingering on the interface between two fluids with different viscosities confined in a Hele-Shaw cell. Both phenomena are described by the same equations with scales differing by a factor of up to 10(-9). We also report the quasiclassical wave function of the droplet in an inhomogeneous magnetic field. 相似文献
10.
Oxidation of naphthalene on Co–Mo–O, NiMoO4 and Mg–Mo–O catalysts gives phthalic anhydride, its maximal yield being about 40% on nickel molybdate. On bismuth molybdates and the Sn–Sb–O system, naphthalene is mainly oxidized to carbon oxides.
Co–Mo–O, NiMoO4 Mg–Mo–O , ( 40%) . Sn–Sb–O .相似文献