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101.
Prof. Dr. Robin B. Bedford John G. Bowen Russell B. Davidson Dr. Mairi F. Haddow Annabelle E. Seymour‐Julen Dr. Hazel A. Sparkes Dr. Ruth L. Webster 《Angewandte Chemie (International ed. in English)》2015,54(22):6591-6594
Palladium(II) acetate is readily converted into [Pd3(μ2‐OH)(OAc)5] ( 1 ) in the presence of water in a range of organic solvents and is also slowly converted in the solid state. Complex 1 can also be formed in nominally anhydrous solvents. Similarly, the analogous alkoxide complexes [Pd3(μ2‐OR)(OAc)5] ( 3 ) are easily formed in solutions of palladium(II) acetate containing a range of alcohols. An examination of a representative Wacker‐type oxidation shows that the Pd‐OH complex 1 and a related Pd‐oxo complex 4 can be excluded as potential catalytic intermediates in the absence of exogenous water. 相似文献
102.
Vasu SS Huynh LK Davidson DF Hanson RK Golden DM 《The journal of physical chemistry. A》2011,115(12):2549-2556
Reactions of hydroxyl (OH) radicals with 1-butene (k(1)), trans-2-butene (k(2)), and cis-2-butene (k(3)) were studied behind reflected shock waves over the temperature range 880-1341 K and at pressures near 2.2 atm. OH radicals were produced by shock-heating tert-butyl hydroperoxide, (CH(3))(3)-CO-OH, and monitored by narrow-line width ring dye laser absorption of the well-characterized R(1)(5) line of the OH A-X (0, 0) band near 306.7 nm. OH time histories were modeled using a comprehensive C(5) oxidation mechanism, and rate constants for the reaction of OH with butene isomers were extracted by matching modeled and measured OH concentration time histories. We present the first high-temperature measurement of OH + cis-2-butene and extend the temperature range of the only previous high-temperature study for both 1-butene and trans-2-butene. With the potential energy surface calculated using CCSD(T)/6-311++G(d,p)//QCISD/6-31G(d), the rate constants and branching fractions for the H-abstraction channels of the reaction of OH with 1-butene were calculated in the temperature range 300-1500 K. Corrections for variational and tunneling effects as well as hindered-rotation treatments were included. The calculations are in good agreement with current and previous experimental data and with a recent theoretical study. 相似文献
103.
Jeffery BJ Whitelaw EL Garcia-Vivo D Stewart JA Mahon MF Davidson MG Jones MD 《Chemical communications (Cambridge, England)》2011,47(45):12328-12330
In this paper we demonstrate the utility of Group 4 metals for the well-controlled and stereoselective (syndiotactic) ring opening polymerization (ROP) of rac-β-butyrolactone (BBL) and their ability to form copolymers. 相似文献
104.
This paper addresses the isomorphism problem for the universal (non-self-adjoint) operator algebras generated by a row contraction subject to homogeneous polynomial relations. We find that two such algebras are isometrically isomorphic if and only if the defining polynomial relations are the same up to a unitary change of variables, and that this happens if and only if the associated subproduct systems are isomorphic. The proof makes use of the complex analytic structure of the character space, together with some recent results on subproduct systems. Restricting attention to commutative operator algebras defined by a radical ideal of relations yields strong resemblances with classical algebraic geometry. These commutative operator algebras turn out to be algebras of analytic functions on algebraic varieties. We prove a projective Nullstellensatz connecting closed ideals and their zero sets. Under some technical assumptions, we find that two such algebras are isomorphic as algebras if and only if they are similar, and we obtain a clear geometrical picture of when this happens. This result is obtained with tools from algebraic geometry, reproducing kernel Hilbert spaces, and some new complex-geometric rigidity results of independent interest. The C?-envelopes of these algebras are also determined. The Banach-algebraic and the algebraic classification results are shown to hold for the wot-closures of these algebras as well. 相似文献
105.
106.
Kelly A. Davidson 《Journal of organometallic chemistry》2007,692(10):1871-1874
PhGeCl3 reacts with Na{[OP(OEt)2]3CoCp} to give the six-coordinate complex PhCl2Ge{[OP(OEt)2]3CoCp}, characterised spectroscopically and by an X-ray crystal structure determination which showed a firmly-attached tridentate ligand [Ge-O 1.973(2) Å]. 相似文献
107.
108.
109.
This paper deals with robustness of adaptive control of continuoussystems subject to known output delay, input saturation, unmodelledlinear dynamics, and bounded disturbances. A simple gradient-typealgorithm with a relative deadzone is used. The relative deadzoneis built with an estimated contribution of the unmodelled dynamicsto the system output. The basic tool used for stability androbustness analysis is Gronwall's lemma. 相似文献
110.
F. Krauss E. H. Riesenfeld F. Feld J. Kendall A. W. Davidson und W. Böttger 《Fresenius' Journal of Analytical Chemistry》1926,69(4):178-179
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