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31.
Stereocontrolled synthesis of (S)-Fmoc-β-nitroalanine (20) was accomplished from (R)-Fmoc-Ser(tBu)-OH (14) in a total of six steps via an oxime. The oxime (17) was obtained from (R)-Fmoc-Ser(tBu)-H (16), which in turn was obtained by reduction of Weinreb amide (15). Oxidation of oxime was realized with peroxytrifluoroacetic acid at a neutral pH at 0 °C. After removal of the tBu protecting group with 90% TFA/H2O, the hydroxyl group was oxidized with Jones reagent to afford (S)-Fmoc-β-nitroalanine (20) in overall good yield. 相似文献
32.
The jump of the Milnor number of an isolated singularity f 0 is the minimal non-zero difference between the Milnor numbers of f 0 and one of its deformations (f s ). We prove that for the singularities in the X 9 singularity class their jumps are equal to 2. 相似文献
33.
We prove that for each universal algebra ${(A, \mathcal{A})}$ of cardinality ${|A| \geq 2}$ and infinite set X of cardinality ${|X| \geq | \mathcal{A}|}$ , the X-th power ${(A^{X}, \mathcal{A}^{X})}$ of the algebra ${(A, \mathcal{A})}$ contains a free subset ${\mathcal{F} \subset A^{X}}$ of cardinality ${|\mathcal{F}| = 2^{|X|}}$ . This generalizes the classical Fichtenholtz–Kantorovitch–Hausdorff result on the existence of an independent family ${\mathcal{I} \subset \mathcal{P}(X)}$ of cardinality ${|\mathcal{I}| = |\mathcal{P}(X)|}$ in the Boolean algebra ${\mathcal{P}(X)}$ of subsets of an infinite set X. 相似文献
34.
Karol?Ko?odziej Szymon?Szczypiński 《The European Physical Journal C - Particles and Fields》2009,64(4):645-651
We present results for the lowest order cross sections, calculated with the complete set of standard model Feynman diagrams,
of all possible detection channels of the associated production of the top quark pair and the light Higgs boson, which may
be used for determination of the top–Higgs Yukawa coupling at the future e
+
e
− linear collider. We show that, for typical particle identification cuts, the background contributions are large. In particular,
the QCD background contributions are much bigger than could be expected when taking into account a possibly low virtuality
of exchanged gluons. Moreover, we include the initial state radiation effects and discuss the dependence of the cross sections
on the Higgs boson and top quark masses. 相似文献
35.
Szymon G?a?b 《Topology and its Applications》2011,158(1):93-100
An ideal J of subsets of a Polish space X has (LK) property whenever for every sequence (An) of analytic sets in X, if lim supn∈HAn∉J for each infinite H then ?n∈G∉J for some infinite G. In this note we present a new class of σ-ideals with (LK) property. 相似文献
36.
Support-type properties of generalized convex functions 总被引:1,自引:0,他引:1
Szymon W?sowicz 《Journal of Mathematical Analysis and Applications》2010,365(1):415-747
Chebyshev systems induce in a natural way a concept of convexity. The functions convex in this sense behave in many aspects similarly to ordinary convex functions. In this paper support-type properties are investigated. Using osculatory interpolation, the existence of support-like functions is established for functions convex with respect to Chebyshev systems. Unique supports are determined. A characterization of the generalized convexity via support properties is presented. 相似文献
37.
Szymon Peszat 《Probability Theory and Related Fields》1994,98(1):113-136
Summary The large deviation principle obtained by Freidlin and Wentzell for measures associated with finite-dimensional diffusions is extended to measures given by stochastic evolution equations with non-additive random perturbations. The proof of the main result is adopted from the Priouret paper concerning finite-dimensional diffusions. Exponential tail estimates for infinite-dimensional stochastic convolutions are used as main tools. 相似文献
38.
Szymon Żeberski 《Mathematical Logic Quarterly》2007,53(1):38-42
Assume that there is no quasi-measurable cardinal not greater than 2ω . We show that for a c. c. c. σ -ideal 𝕀 with a Borel base of subsets of an uncountable Polish space, if 𝒜 is a point-finite family of subsets from 𝕀, then there is a subfamily of 𝒜 whose union is completely nonmeasurable, i.e. its intersection with every non-small Borel set does not belong to the σ -field generated by Borel sets and the ideal 𝕀. This result is a generalization of the Four Poles Theorem (see [1]) and a result from [3]. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
39.
40.
The Isbell, compact-open and point-open topologies on the set C(X,R) of continuous real-valued maps can be represented as the dual topologies with respect to some collections α(X) of compact families of open subsets of a topological space X. Those α(X) for which addition is jointly continuous at the zero function in Cα(X,R) are characterized, and sufficient conditions for translations to be continuous are found. As a result, collections α(X) for which Cα(X,R) is a topological vector space are defined canonically. The Isbell topology coincides with this vector space topology if and only if X is infraconsonant. Examples based on measure theoretic methods, that Cα(X,R) can be strictly finer than the compact-open topology, are given. To our knowledge, this is the first example of a splitting group topology strictly finer than the compact-open topology. 相似文献