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81.
Mark S. Wrighton 《Journal of organometallic chemistry》1976,120(3):C58-C62
Photolysis of 1,2-divinyl- and 1-phenyl-2-vinyltetramethyldisilane and 1-phenylethenylpentamethyldisilane has been investigated. All three compounds afforded a new type of silicon—carbon double-bonded intermediate via photorearrangement of a silyl group to the terminal carbon of a vinyl group. 相似文献
82.
83.
Adel Attia Markéta Zukalová Jiří Rathouský Arnošt Zukal Ladislav Kavan 《Journal of Solid State Electrochemistry》2005,9(3):138-145
A mesoporous electrode material whose structure is composed of anatase nanocrystals stabilized by alumina is reported. Powder X-ray diffraction shows the anatase phase only, but micro-Raman spectroscopy shows that the materials have a core-shell morphology with grains of bulk anatase covered by a thin rutile layer on the surface. This structure is unique when compared to analogous materials stabilized by zirconia (PNNL-1). Nitrogen adsorption isotherms demonstrate a monotonous increase in surface area and mesopore volume with increasing Al content. Thin film electrodes from these materials were characterized by lithium insertion electrochemistry. Cyclic voltammograms exhibit significant differences in Li accommodation in Al-free and Al-stabilized materials. 相似文献
84.
Jeffrey T. Culp Franz Frye Mark W. Meisel Daniel R. Talham 《Coordination chemistry reviews》2005,249(23):2642-2648
Studies of metal cyanide thin films prepared directly at interfaces are reviewed. The systems range from monolayers, single-layer analogs of Prussian blue-like networks, to bulk powders prepared as thin films. Monolayer networks are prepared at the air/water interface and transferred to solid supports using Langmuir-Blodgett film methods. Films of bulk materials are prepared directly on solid surfaces using a templated sequential deposition procedure. The magnetic properties of the films have been explored, and in some cases, these monolayers and surface films give rise to new behavior that is only possible because of the fabrication method or thin film architecture. The methods of synthesis can generate oriented samples, even when the materials are poorly crystalline. Furthermore, the interface-assembled networks are inherently anisotropic, leading to phenomena not present in the solid-state analogs, such as anisotropic photomagnetism in a thin film of RbjCok[Fe(CN)6]l·nH2O. 相似文献
85.
Solubility behaviors of binary mixtures of CFCl3 (R-11), CFCl2-CF2Cl (R-113), CHCl3 (R-20), CDCl3 (R-20-d), CHCl2–CF3 (R-123) with room-temperature ionic liquid [bmim][PF6] (1-butyl-3-methylimidazolium hexafluorophosphate) have been investigated using the volumetric and cloud-point methods, since all the systems show liquid–liquid equilibria (LLE). Large immiscibility (LLE) gaps of the perhalogenated compounds (R-11 and R-113) in the ionic liquid have been drastically reduced by the addition of only one hydrogen (or deuterium) in these compounds. The R-123 + [bmim][PF6] binary system belongs to the Type-V fluid behavior. Noticeably large negative values (−2 to −8 cm3 mol−1) of the excess molar volume in the ionic liquid-rich side solution have been observed for all the present systems. Experimental LLE data have been well correlated by the use of the NRTL (non-random two liquid) activity coefficient model. 相似文献
86.
Kar S Chanda N Mobin SM Urbanos FA Niemeyer M Puranik VG Jimenez-Aparicio R Lahiri GK 《Inorganic chemistry》2005,44(5):1571-1579
The reaction of cis-Ru(acac)2(CH3CN)2 (acac = acetylacetonate) with 2,2'-dipyridylamine (L) in ethanolic medium resulted in facile one-pot synthesis of stable [(acac)2RuIII(L)]ClO4 ([1]ClO4), trans-[(acac)2RuII(L)2] (2), trans-[(acac)2RuIII)L)2]ClO4 ([2]ClO4), and cis-[(acac)2RuII(L)2] (3). The bivalent congener 1 was generated via electrochemical reduction of [1]ClO4. Although in [1]+ the dipyridylamine ligand (L) is bonded to the metal ion in usual bidentate fashion, in 2/[2]+ and 3, the unusual monodentate binding mode of L has been preferentially stabilized. Moreover, in 2/[2]+ and 3, two such monodentate L's have been oriented in the trans- and cis-configurations, respectively. The binding mode of L and the isomeric geometries of the complexes were established by their single-crystal X-ray structures. The redox stability of the Ru(II) state follows the order 1 < 2 < 3. In contrast to the magnetic moment obtained for [1]ClO4, mu = 1.84 muB at 298 K, typical for low-spin Ru(III) species, the compound [2]ClO4 exhibited an anomalous magnetic moment of 2.71 muB at 300 K in the solid state. The variable-temperature magnetic measurements showed a pronounced decrease of the magnetic moment with the temperature, and that dropped to 1.59 muB at 3 K. The experimental data can be fitted satisfactorily using eq 2 that considered nonquenched spin-orbit coupling and Weiss constant in addition to the temperature-independent paramagnetism. [1]ClO4 and [2]ClO4 displayed rhombic and axial EPR spectra, respectively, in both the solid and the solution states at 77 K. 相似文献
87.
Stols Lucy Kulkarni Gopal Harris Ben G. Donnelly Mark I. 《Applied biochemistry and biotechnology》1997,63(1):153-158
Applied Biochemistry and Biotechnology - The malic enzyme gene ofAscaris suum was cloned into the vector pTRC99a in two forms encoding alternative arnino-termini. The resulting plasmids, pMEAl and... 相似文献
88.
89.
Mark Pollicott 《Communications in Mathematical Physics》1987,113(1):137-154
For the strong unstable foliation (or horocycle foliation) of an Anosov flow there exists a unique transverse measure called the Margulis measure. In this paper we extend Margulis' results to more general transverse distributions for the foliation. As an application we derive our main result: The non-zero analytic extension to a strip of the Selberg zeta function for compact surfaces of constant negative curvature persists under small perturbations in the metric. There is an equivalent formulation in terms of the Fourier transform of the correlation function. 相似文献
90.
R. R. Mendel Kimball A. Milton James H. Reid Mark A. Samuel 《Zeitschrift fur Physik C Particles and Fields》1986,32(4):517-520
Several methods to determine (or set an upper bound on) the mass of the tau neutrino are described. The decay spectrum of \(\tau \to e\bar \nu _e \nu _\tau \) near the high center-of-mass electron-energy end is particularly sensitive to the tau-neutrino mass. It is shown that an upper bound of 20 MeV or lower may be feasible. In addition, improved limits on the mass and mixing angle of a heavy component of the tau-neutrino may be readily obtained. We also discuss the purely leptonic decays of theD andF mesons, and show how measurements of the ratiosB(D→τντ/B(D→μνμ,B(F→τντ/B(D→μνμ can be sensitive to tau-neutrino masses of 30 MeV or greater. 相似文献