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71.
The reflexivity and transitivity of subspaces of Toeplitz operators on the Hardy space on the upper half-plane are investigated. The dichotomic behavior (transitive or reflexive) of these subspaces is shown. It refers to the similar dichotomic behavior for subspaces of Toeplitz operators on the Hardy space on the unit disc. The isomorphism between the Hardy spaces on the unit disc and the upper half-plane is used. To keep weak* homeomorphism between L ∞ spaces on the unit circle and the real line we redefine the classical isomorphism between L 1 spaces. 相似文献
72.
We start by introducing a Čech homology with compact supports which we then use in order to construct an infinite-dimensional
homology theory. Next we show that under appropriate conditions on the nonlinearity there exists a ground state solution for
a semilinear Schr?dinger equation with strongly indefinite linear part. To this solution there corresponds a nontrivial critical
group, defined in terms of the infinite-dimensional homology mentioned above. Finally, we employ this fact in order to construct
solutions of multibump type. Although our main purpose is to survey certain homological methods in critical point theory,
we also include some new results.
Dedicated to Felix Browder on the occasion of his 80th birthday 相似文献
73.
Marlena Pięta Jacek Kędzia Dorota Kowalczyk Jakub Wojciechowski Wojciech M. Wolf Tomasz Janecki 《Tetrahedron》2019,75(17):2495-2505
An efficient, versatile, enantioselective synthesis of 1,3-disubstituted and 1,3,6-trisubstituted 5-methylidenedihydrouracils applying Horner-Wadsworth Emmons methodology was developed. Starting 1,3-disubstituted 5-diethoxyphosphoryluracils were subjected to reduction of the double bond or addition of various Grignard reagents and obtained Horner-Wadsworth Emmons reagents were used for the olefination of formaldehyde. Enantioselective synthesis of 1,3,6-trisubstituted 5-methylidenedihydrouracils was accomplished by introducing (R,R)- or (S,S)-di(1-phenylethylamino)phosphoryl groups as chiral auxiliary. Additions of Grignard reagents in the presence of these groups were highly and complimentary diastereoselective (de?~?80%). Further separation of the diastereomeric mixtures by column chromatography enabled synthesis of (R)- and (S)-1,3,6-trisubstituted-5-methylidenedihydrouracils with ee?≥?98%. Furthermore, absolute configuration of the adducts and final products was established using single crystal X-ray analysis. Stereochemical course of the addition reactions is also discussed. 相似文献
74.
Gorzkiewicz Krzysztof Mietelski Jerzy Wojciech Kierepko Renata Brudecki Kamil 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1311-1321
Journal of Radioanalytical and Nuclear Chemistry - This paper presents results of the development process of low-background, digital gamma-rays spectrometer equipped with Broad Energy Germanium... 相似文献
75.
Antimicrobial properties of biosynthesized silver nanoparticles studied by flow cytometry and related techniques 下载免费PDF全文
Viorica Railean‐Plugaru Pawel Pomastowski Katarzyna Rafinska Magdalena Wypij Wojciech Kupczyk Hanna Dahm Marek Jackowski Boguslaw Buszewski 《Electrophoresis》2016,37(5-6):752-761
This work reports the effect of silver bionanoparticles (Bio(AgNPs) synthesized by Actinobacteria CGG 11n on selected Gram (+) and Gram (–) bacteria. Flow cytometry, classical antibiogram method and fluorescent microscopy approach was used for evaluation of antimicrobial activity of Bio(AgNPs) and their combination with antibiotics. Furthermore, the performed research specified the capacity of flow cytometry method as an alternative to the standard ones and as a complementary method to electromigration techniques. The study showed antibacterial activity of both BioAgNPs and the combination of antibiotics/BioAgNPs against all the tested bacteria strains in comparison with a diffusion, dilution and bioautographic methods. The synergistic effect of antibiotics/BioAgNPs combination (e.g. kanamycin, ampicillin, neomycin and streptomycin) was found to be more notable against Pseudomonas aeruginosa representing a prototype of multi‐drug resistant “superbugs” for which effective therapeutic options are very limited. 相似文献
76.
Irena Gancarz Marek Bryjak Joanna Wolska Anna Siekierka Wojciech Kujawski 《Chemical Papers》2016,70(3):350-355
Porous polypropylene membranes were coated with plasma polymerized titanium isopropoxide in a 75 kHz plasma reactor. It was noted that the presence of air in the plasma chamber increased the amount of deposited polymer. Selection of the process parameters enabled obtaining membranes with up to 300 εg cm?2 of polymerized titanium isopropoxide. Deposition of the titanium oxide layer resulted in the reduction of permeate flux but it significantly improved the membrane photocleaning ability. The recovery index reached the level of 95 % for membranes with the highest amount of the titanium oxide deposit. 相似文献
77.
Explicitly correlated Gaussian (ECG) functions with carefully optimized non-linear parameters are used to calculate the electronic energies of He2+ and LiH at their equilibrium internuclear distances. The obtained variational upper bounds (−4.99464392 and −8.070538 hartree, respectively) are the lowest reported to date. By extrapolating results obtained with various expansion lengths, the estimations of the Born–Oppenheimer limits are made. 相似文献
78.
This work presents the application of a new construction of an electronic tongue for the classification of milk originating from various producers. Integrated array of microelectrodes was fabricated from epoxy-glass laminate. PVC membranes with various additives were used as chemosensitive layers. The developed device is capable of recognition of milk samples with high correctness. Moreover, the application of miniaturized reference electrode, integrated on the same substrate, also provided satisfactory results, which can be helpful in future constructions of hand-held electronic tongue systems. 相似文献
79.
Adduct formations of rhodium(II) tetraacetate and tetratrifluoroacetate with some 1H-imidazoles, oxazoles, thiazoles, 1H-pyrazoles and isoxazole have been investigated by the use of 1H, 13C, 15N NMR and electronic absorption spectroscopy (VIS) in the visible range. Azoles tend to form axial adducts containing rhodium(II) tetraacylates bonded via nitrogen atom. Bulky substituents close to the nitrogen atom prevent the Rh--N bond formation, and in several cases switch over the binding site to the oxygen or sulphur atoms. The (15)N adduct formation shift Deltadelta(15N) (Deltadelta = delta(adduct) - delta(ligand)) varied from ca - 40 to - 70 ppm for the nitrogen atom involved in complexation, and of a few parts per million only, from ca - 6 to 3 ppm, for the non-bonded nitrogen atom within the same molecule. The Deltadelta(1H) values do not exceed one ppm; Deltadelta(13C) ranges from - 1 to 6 ppm. Various complexation modes have been proved by electronic absorption spectroscopy in the visible region (VIS). For comparison purposes, some adducts of pyridine, thiophene and furan derivatives have been measured as well. The experimental findings were compared with calculated chemical shifts, obtained by means of DFT B3LYP method, using 6-311 + G(2d,p), 6-31(d)/LanL2DZ and 6-311G(d,p) basis set. 相似文献
80.
Benfatto M Della Longa S Hatada K Hayakawa K Gawelda W Bressler C Chergui M 《The journal of physical chemistry. B》2006,110(29):14035-14039
A full multiple theoretical model (MXAN) is applied to fit picosecond difference X-ray absorption spectra at the ruthenium L(3) edge upon photoexcitation of aqueous [RuII(bpy)3]2+. We show that fitting difference spectra allows an increase in sensitivity, such that slight structural changes can be retrieved, which are not detected in fitting full spectra. The Ru-N bond distances of the excited complex in the (3)MLCT state are in good agreement with recently published values. The implementation of the present approach to L-edge spectra and its high sensitivity opens opportunities for its extension to a large class of experiments where difference X-ray absorption spectra are recorded. 相似文献