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431.
Jurij Svete Andrej Preeren Branko Stanovnik Ljubo Goli
Simona Goli
-Grdadolnik 《Journal of heterocyclic chemistry》1997,34(4):1323-1328
Reaction of rel-(4R,5R)-4-benzoylamino-5-phenyl-3-pyrazolidinone (4) with aromatic aldehydes 5a-f gave the corresponding (1Z)-rel-(4R,5R)-1-arylmethylene-4-benzoylamino-5-phenyl-3-pyrazolidinon-1-azomethinimines 6a-f . 1,3-Dipolar cycloadditions of azomethinimines 6a-f to various dipolarophiles, which were found to proceed regio- and stereo-selectively, afforded the corresponding pyrazolo[1,2-a]-pyrazoles 8a-f, 10 , and 13–16 . Reaction of azomethinimine 6a with hydrogen cyanide gave rel-(5R,6R)-6-benzoylamino-5,6-dihydro-3,5-diphenyl-1-oxo-1H,7H-pyrazolo[1,2-a][1,2,3]triazole (18) as a representative of a new ring system. 相似文献
432.
4-(Hydroxymethyl)piperidine was selectively protected with tetrahydropyranyl group in several steps to give the title compound. Use of 1H and 19F nmr spectra in structure determination is discussed. 相似文献
433.
434.
435.
436.
Andrej Bauer Karin Cvetko-Vah Mai Gehrke Samuel J. van Gool Ganna Kudryavtseva 《Topology and its Applications》2013
We prove that the category of left-handed strongly distributive skew lattices with zero and proper homomorphisms is dually equivalent to a category of sheaves over local Priestley spaces. Our result thus provides a non-commutative version of classical Priestley duality for distributive lattices and generalizes the recent development of Stone duality for skew Boolean algebras. 相似文献
437.
Alon, Angel, Benjamini and Lubetzky [1] recently studied an old problem of Euler on sumsets for which all elements of A+B are integer squares. Improving their result we prove: 1. There exists a set A of 3 positive integers and a corresponding set B?[0,N] with |B|?(logN)15/17, such that all elements of A+B are perfect squares. 2. There exists a set A of 3 integers and a corresponding set B?[0,N] with |B|?(logN)9/11, such that all elements of the sets A, B and A+B are perfect squares. The proofs make use of suitably constructed elliptic curves of high rank. 相似文献
438.
Ulrike Grossner Jens S. Christensen Bengt G. Svensson Andrej Yu. Kuznetsov 《Superlattices and Microstructures》2007,42(1-6):294
In order to obtain p-type ZnO, the incorporation of group-V elements on oxygen sites has received lots of attention. Recently, the implantation of Sb+ ions into ZnO has been shown to lead to reduced n-type conduction. However, a compensating effect due to implantation damage could not be ruled out. Therefore, single-crystal ZnO has been hydrothermally grown with additional Sb2O3, Sb2O5, and K(SbO)C4H4O6 in the solution. Schottky barrier contacts have been deposited onto the () face. Capacitance–voltage measurements and thermal admittance spectroscopy have been used for electrical characterization, and secondary ion mass spectrometry was used to measure the Sb content in the samples. Clearly, all samples exhibited n-type conduction. A competition between the incorporation of oxygen and antimony is suggested. 相似文献
439.
Fidanchevski Emilija Angjusheva Biljana Jovanov Vojo Murtanovski Pece Vladiceska Ljubica Aluloska Nikolina Stamatovska Nikolic Jelena Krneta Ipavec Andrej Šter Katarina Mrak Maruša Dolenec Sabina 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):685-694
Journal of Radioanalytical and Nuclear Chemistry - Huge quantities of fly ash and bottom ash are generated from thermal power plants and it presents great concern for country, mainly due... 相似文献
440.
Let
be a nontrivial probability measure on the unit circle
the density of its absolutely continuous part,
its Verblunsky coefficients, and
its monic orthogonal polynomials. In this paper we compute the coefficients of
in terms of the
. If the function
is in
, we do the same for its Fourier coefficients. As an application we prove that if
and if
is a polynomial, then with
and S the left-shift operator on sequences we have
We also study relative ratio asymptotics of the reversed polynomials
and provide a necessary and sufficient condition in terms of the Verblunsky coefficients of the measures
and
for this difference to converge to zero uniformly on compact subsets of
. 相似文献