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81.
82.
Xuan Thinh Duong Irina Holmes Ji Li Brett D. Wick Dongyong Yang 《Journal of Functional Analysis》2019,276(4):1007-1060
In this paper we establish the characterization of the weighted BMO via two weight commutators in the settings of the Neumann Laplacian on the upper half space and the reflection Neumann Laplacian on with respect to the weights associated to and respectively. This in turn yields a weak factorization for the corresponding weighted Hardy spaces, where in particular, the weighted class associated to is strictly larger than the Muckenhoupt weighted class and contains non-doubling weights. In our study, we also make contributions to the classical Muckenhoupt–Wheeden weighted Hardy space (BMO space respectively) by showing that it can be characterized via the area function (Carleson measure respectively) involving the semigroup generated by the Laplacian on and that the duality of these weighted Hardy and BMO spaces holds for Muckenhoupt weights with while the previously known related results cover only . We also point out that this two weight commutator theorem might not be true in the setting of general operators L, and in particular we show that it is not true when L is the Dirichlet Laplacian on . 相似文献
83.
Kirill V. Zaitsev Yulia A. Piskun Yuri F. Oprunenko Sergey S. Karlov Galina S. Zaitseva Irina V. Vasilenko Andrei V. Churakov Sergei V. Kostjuk 《Journal of polymer science. Part A, Polymer chemistry》2014,52(9):1237-1250
The aluminum complexes containing two iminophenolate ligands of the type (p‐XC6H4NCHC6H4O‐o)2AlR' (R′=Me ( 3, 4 ) or R′=O(CH2)4OCH=CH2 ( 5, 6 ), X=H ( 3, 5 ), F( 4, 6 )) were synthesized and characterized by 1H, 13C NMR spectroscopy, and X‐ray crystallography. The reaction of AlMe3 with two equivalents of substituted iminophenols gave five‐coordinated {ONR}2AlMe ( 3, 4 ) complexes. Subsequent reaction of these methyl complexes with unsaturated alcohol, HO(CH2)4OCH=CH2, resulted in target compounds 5 and 6 in a good yield. It was shown that the complexes ( 3 ‐ 6 ) are monomeric in solution (NMR) and in solid state (X‐ray analysis). The catalytic activity of the complexes 5 and 6 towards ring‐opening polymerization (ROP) of ?‐caprolactone and d,l ‐lactide was assessed. Complex 5 showed higher activity as compared with 6 , while both of these catalysts induced controlled homo‐ and copolymerization to afford the macromonomers with high content of vinyl ether end groups (Fn > 80%) in a broad range of molecular weights (Mn = 4000–30,000 g mol?1) with relatively narrow MWD (Mw/Mn = 1.1–1.5). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1237–1250 相似文献
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86.
Nikolai V. Lukashev Alexei D. Averin Protais Muhayimana Marina A. Kazankova Irina P. Beletskaya 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Addition of P-halogenophosphaalkenes to I-alkoxyalkynes provides either 2-phosphabutadienes 2 or P(II1)-substituted allenes 3. The reaction o f P-halogenophosphaalkenes I with I-aminoalkynes leads to the phosphetines 4 wa 5 - the product of 1,2-addition reaction. 相似文献
87.
Mikhael Pudovik Wolf Habicher Irina Nikolaeva Alexander Burilov Vladimir Reznik Alexander Konovalov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Reactions of calix[4]resorcinarenes, bearing aliphatic radicals of different length, with P(III)-halides results in the formation of cyclic chlorophosphites and chlorophosphates. 相似文献
88.
Oleg G. Sinyashin Irina P. Romanova Gulshat G. Yusupova Valery I. Kovalenko Yuri Y. Efremov Irina I. Vandyukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Data on the structure of cycloadducts of organophosphorus dipolar reagents and fullerenes arc absent, to our knowledge. We died the reactions and the shucturc of cycloadducts of phosphorylated azidcs and nitrile oxide with [60]fullcrcnc. The cycloaddition of diphcnylphosphinic llzide to fullcrme has bcm determined to lead to the 1 -[(N-diphenylphosphoryl)amino]-2-hydroxy[6O]hllcrme (l), the mixhuc of phosphorylated aziridinofullcrcne (2) and derivative of fullerne (3) with one aziridine fragment and one aminohydmxy-fragment, or to product (4), depending on the conditions of don . 相似文献
89.
Pavel Arsenyan Irina Shestakova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2427-2430
The cytotoxic activity of a series of methylammonium tellurates on human fibrosarcoma HT-1080, mouse hepatoma MG-22A, and mouse fibroblasts 3T3 cell lines is described. The role of tellurates as free radical regulators is discussed. 相似文献
90.
Vladimir I. Galkin Gulchira M. Saakyan Irina V. Galkina Rafael A. Cherkasov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Elaboration of effective methods of selective phosphorylation of α,β-unsaturated carbonyl compounds containing simultaneously C[dbnd]C and C[dbnd]O bonds, which may compete with each other or react consistently one after another, is one of the most complex problems in the modern organophosphorus synthesis. On the basis of our previous systematic investigations of kinetics and mechanism of the Pudovik and Abramov reactions in the series of α,β-unsaturated carbonyl compounds we have suggested three possible ways to solve this problem: a) soft reaction conditions, regulated by solvent, catalyst and temperature; b) interface catalysis; c) metallocomlex catalysis (reaction in the coordination sphere of transition metal). 相似文献