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61.
Jochen Lutz The Vinh Ho Richard H. Fish Andreas Schmid 《Journal of organometallic chemistry》2004,689(25):4783-4790
The biocatalytic, regioselective hydroxylation of 2-hydroxybiphenyl to the corresponding catechol was accomplished utilizing the monooxygenase 2-hydroxybiphenyl 3-monooxygenase (HbpA). The necessary natural 1,4-dihydronicotinamde adenine dinucleotide (NADH) co-factor for this biocatalytic process was replaced by a biomimetic co-factor, N-benzyl-1,4-dihydronicotinamide, 1b. The interaction between the flavin (FAD) containing HbpA enzyme and the corresponding biomimetic NADH compound, N-benzyl-1,4-dihdronicotinamide, 1b, for hydride transfer, was shown to readily occur. The in situ recycling of the reduced NADH biomimic 1b from 1a was accomplished with [Cp*Rh(bpy)H](Cl); however, productive coupling of this regeneration reaction to the enzymatic hydroxylation reaction was not totally successful, due to a deactivation process concerning the HbpA enzyme peripheral groups; i.e., -SH or -NH2 possibly reacting with the precatalyst, [Cp*Rh(bpy)(H2O)](Cl)2, and thus inhibiting the co-factor regeneration process. The deactivation mechanism was studied, and a promising strategy of derivatizing these peripheral -SH or -NH2 groups with a polymer containing epoxide was successful in circumventing the undesired interaction between HbpA and the precatalyst. This latter strategy allowed tandem co-factor regeneration using 1a or 2a, [Cp*Rh(bpy)(H2O)](Cl)2, and formate ion, in conjunction with the polymer bound, FAD containing HbpA enzyme to provide the catechol product. 相似文献
62.
A. S. Mellit V. I. Rabanovich Yu. S. Samoilenko 《Functional Analysis and Its Applications》2004,38(2):157-160
We describe the set
of values of the parameter for which there exists a Hilbert space H and n partial reflections A
1,...,A
n
(self-adjoint operators such that A
k
3
=Ak or, which is the same, self-adjoint operators whose spectra belong to the set {-1,0,1}) whose sum is equal to the scalar operator I
H
. 相似文献
63.
For a dense G-set of parameters, the irrational rotation algebrais shown to contain infinitely many C*-subalgebras satisfyingthe following properties. Each subalgebra is isomorphic to adirect sum of two matrix algebras of the same (perfect square)dimension; the Fourier transform maps each summand onto theother; the corresponding unit projection is approximately central;the compressions of the canonical generators of the irrationalrotation algebra are approximately contained in the subalgebra.2000 Mathematics Subject Classification 46L80, 46L40, 46L35. 相似文献
64.
We analyze the decomposition rank (a notion of covering dimensionfor nuclear C*-algebras introduced by E. Kirchberg and the author)of subhomogeneous C*-algebras. In particular, we show that asubhomogeneous C*-algebra has decomposition rank n if and onlyif it is recursive subhomogeneous of topological dimension n,and that n is determined by the primitive ideal space. As an application, we use recent results of Q. Lin and N. C.Phillips to show the following. Let A be the crossed productC*-algebra coming from a compact smooth manifold and a minimaldiffeomorphism. Then the decomposition rank of A is dominatedby the covering dimension of the underlying manifold. 2000 MathematicsSubject Classification 46L85, 46L35. 相似文献
65.
The aim of this note is to give a short proof that 2-local derivations on , the matrix algebra over the complex numbers are derivations and to give a shorter proof that 2-local *-automorphisms on are *-automorphisms.
66.
E. V. Troitsky 《Proceedings of the American Mathematical Society》2003,131(11):3411-3422
We address the problem of interrelations between the properties of an action of a discrete group on a compact Hausdorff space and the algebraic and analytical properties of the module of all continuous functions over the algebra of invariant continuous functions . The present paper is a continuation of our joint paper with M. Frank and V. Manuilov. Here we prove some statements inverse to the ones obtained in that paper: we deduce properties of actions from properties of modules. In particular, it is proved that if for a uniformly continuous action the module is finitely generated projective over , then the cardinality of orbits of the action is finite and fixed. Sufficient conditions for existence of natural conditional expectations are obtained.
67.
Kazunori Kodaka Hiroyuki Osaka 《Proceedings of the American Mathematical Society》2001,129(4):999-1003
A -algebra is said to have the FS-property if the set of all self-adjoint elements in has a dense subset of elements with finite spectrum. We shall show that this property is not stable under taking the minimal -tensor products even in case of separable nuclear -algebras.
68.
The Tracial Topological Rank of C*-Algebras 总被引:11,自引:0,他引:11
We introduce the notion of tracial topological rank for C*-algebras.In the commutative case, this notion coincides with the coveringdimension. Inductive limits of C*-algebrasof the form PMn(C(X))P,where X is a compact metric space with dim X k, and P is aprojection in Mn(C(X)), have tracial topological rank no morethan k. Non-nuclear C*-algebras can have small tracial topologicalrank. It is shown that if A is a simple unital C*-algebra withtracial topological rank k (< ), then
- (i) A is quasidiagonal,
- (ii) A has stable rank 1,
- (iii) A has weakly unperforatedK0(A),
- (iv) A has the following Fundamental Comparabilityof Blackadar:if p, q A are two projections with (p) < (q)for all tracialstates on A, then p q
- (ii) A has stable rank 1,
69.
70.
Indium-tin oxide (ITO) films deposited on heated and non-heated glass substrates by a pulsed Nd:YAG laser at 355 nm and ∼2.5 J/cm2 were used in the fabrication of simple organic light-emitting diodes (OLEDs), ITO/(PVK + Alq3 + TPD)/Al. The ITO was deposited on heated glass substrates which possessed resistivity as low as ∼3 × 10−4 Ω cm, optical transmission as high as ∼92% and carrier concentration of about ∼5 × 1020 cm−3, were comparable to the commercial ITO. Substrate heating transformed the ITO microstructure from amorphous to polycrystalline, as revealed by the XRD spectrum. While the polycrystalline ITO produced higher OLED brightness, it was still lower than that on the commercial ITO due to surface roughness. A DLC layer of ∼1.5 nm deposited on this ITO at laser fluence of >12.5 J/cm2 improved its device brightness by suppressing the surface roughness effect. 相似文献