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941.
Artur Nicolau 《Journal d'Analyse Mathématique》1994,62(1):199-224
We study when a Pick-Nevanlinna problem with more than one solution can be solved by an interpolating Blaschke product.
Supported in part by the grant PB85-0374 of the CYCIT, Ministerio de Educación y Ciencia, Spain. 相似文献
942.
LetH
∞ be the algebra of bounded analytic functions in the unit diskD. LetI=I(f
1,...,f
N) be the ideal generated byf
1,...,f
N∈H
∞ andJ=J(f
1,...,f
N) the ideal of the functionsf∈H
∞ for which there exists a constantC=C(f) such that |f(z)|≤C(|f
1
(z)|+...;+|f
N
(z)|),z∈D. It is clear that
, but an example due to J. Bourgain shows thatJ is not, in general, in the norm closure ofI. Our first result asserts thatJ is included in the norm closure ofI ifI contains a Carleson-Newman Blaschke product, or equivalently, if there existss>0 such that
Our second result says that there is no analogue of Bourgain's example in any Hardy spaceH
p, 1≤p<∞. More concretely, ifg∈H
p and the nontangential maximal function of
belongs toL
p (T), theng is in theH
p-closure of the idealI.
Both authors are supported in part by DGICYT grant PB98-0872 and CIRIT grant 1998SRG00052. 相似文献
943.
Artur P. Terzyk Magdalena S. ?wiertnia Marek Wi?niewski Piotr A. Gauden Gerhard Rychlicki Grzegorz S. Szymański 《Applied Surface Science》2007,253(8):4006-4009
We present the results of benzene adsorption at the acidic pH level determined on the series of chemically modified activated carbons and at three temperatures. The influence of carbon surface chemical composition on benzene adsorption is discussed. It is shown that the decrease in the pH level from 7 up to 1.5 increases benzene adsorption and the only exception is carbon modified with gaseous ammonia. Basing on the results of current work and those published previously (for phenol, paracetamol, acetanilide and aniline) and using the results of quantum chemistry calculations (DFT, Gaussian 98) we show, that the value of the energy of interaction with unit positive charge is crucial during the analysis of the influence of pH level on adsorption. Obtained results allow to predict the changes in adsorption of aromatics on carbons with the decrease in the pH level. 相似文献
944.
Artur Guchowski Ewa Czarniecka-Skubina Jarosawa Rutkowska 《Molecules (Basel, Switzerland)》2020,25(23)
This study was performed in order to assess technological characteristics, proximate composition, fatty acids profile, and microbiological safety of sous-vide processed salmon in comparison with steaming and roasting. The cooking loss was lower in the sous-vide method (6.3–9.1%) than in conventional methods (11.6–16.2%). The preparation of salmon using sous-vide was more time- and energy-consuming than steaming. The dry matter content of the salmon fillets was higher in conventionally processed samples than sous-vide due to the evaporation of water, and it was connected with total protein (r = 0.85) and lipid content (r = 0.73). Analysis of the fatty acids profile only revealed significant differences in six fatty acids. All of the heat treatment methods ensured microbiological safety with regard to coagulase-positive Staphylococcus, E. coli, Listeria monocytogenes, and Salmonella spp. However, in sous-vide (57 °C, 20 min) and steamed samples after storage Enterobacteriaceae bacteria (<104) was detected. Summing up, high parameters of sous-vide salmon cooking, when considering both technological parameters, nutritional value, and microbiological status should be recommended. 相似文献
945.
ukasz opusiewicz Emilia Drozowska Paulina Trocer Pawe Kwiatkowski Artur Bartkowiak Annett Gefrom Monika Sienkiewicz 《Molecules (Basel, Switzerland)》2020,25(24)
Plant derived fermented beverages have recently gained consumers’ interest, particularly due to their intrinsic functional properties and presence of beneficial microorganisms. Three variants containing 5%, 10%, and 15% (w/w) of sweet blue lupin (Lupinus angustifolius L. cv. “Boregine”) seeds were inoculated with kefir grains and incubated at 25 °C for 24 h. After processing, beverages were stored in refrigerated conditions (6 °C) for 21 days. Changes in microbial population, pH, bioactive compounds (polyphenolics, flavonoids, ascorbic acid), reducing sugars, and free amino acids were estimated. Additionally, viscosity, firmness, color, and free radicals scavenging properties were determined. Results showed that lactic acid bacteria as well as yeast were capable of growing well in the lupin matrix without any supplementation. During the process of refrigeration, the viability of the microorganisms was over the recommended minimum level for kefir products. Hydrolysis of polysaccharides as well as increase of free amino acids was observed. As a result of fermentation, the beverages showed excellent DPPH, ABTS+·, ·OH, and O2− radicals scavenging activities with a potential when considering diseases associated with oxidative stress. This beverages could be used as a new, non-dairy vehicle for beneficial microflora consumption, especially by vegans and lactose-intolerant consumers. 相似文献
946.
Jacob J. Lacharity Artur K. Mailyan Karen Y. Chen Armen Zakarian 《Angewandte Chemie (International ed. in English)》2020,59(28):11364-11368
An asymmetric total synthesis of [13C4]‐anatoxin‐a ([13C4]‐ 1 ) has been developed from commercially available ethyl [13C4]‐acetoacetate ([13C4]‐ 15 ). The unique requirements associated with isotope incorporation inspired a new, robust, and highly scalable route, providing access to 0.110 g of this internal standard for use in the detection and precise quantification of anatoxin‐a in freshwater. A highlight of the synthesis is a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an enantioselective Morita–Baylis–Hillman (MBH) cyclization. 相似文献
947.
Ricardo M. Campos Alexandre C. P. M. Alves Marco A. L. Lima Artur F. M. Farinha João P. S. Cardoso Prof. Adélio Mendes Dr. José C. S. Costa Prof. Luís M. N. B. F. Santos 《Chemphyschem》2020,21(16):1814-1825
In this study, a homogeneous thin film growth of pentacene onto indium tin oxide (ITO) coated glass surfaces is explored using a high-resolution and reproducible vapor deposition methodology. Moreover, vacuum thermal evaporation of ionic liquids (ILs) ([C2C1im][NTf2] and [C2C1im][OTF]) onto ITO, gold/palladium (AuPd) and pentacene surfaces were performed. A greater wettability behavior of ILs is observed for surfaces containing AuPd. Sequential and simultaneous depositions of ILs and pentacene were explored. Simultaneous depositions lead to the formation of nanocomposites films, consisting of IL micro- and nanodroplets covered by pentacene layers. Plasma surface treatment was used to induce the ILs droplets coalescence and explore the dynamics and phase separation of the nanocomposites. The [C2C1im][OTF] droplets were found to be completely covered with pentacene, which suggests a great affinity between cation-anion pairs and the aromatic moiety. Pentacene films and their nanocomposites with ILs exhibit a typical optical band gap of Egap=1.77 eV, indicating that the nanocomposite phase domains are large enough to behavior as the bulk. 相似文献
948.
Abdigali A. Bakibaev Artur Uhov Victor S. Malkov Svetlana Yu. Panshina 《Journal of heterocyclic chemistry》2020,57(12):4262-4270
Most of the known methods for the synthesis of heterocyclic compounds have disadvantages, such as a long reaction time and aggressive conditions. We have developed a new, rather simple and efficient method for the synthesis of a number of glycoluryls and hydantoins in water using a etidronic acid (HEDP) as “Green catalyst.” So, for the first time, the condensation reaction of ureas with 1, 2-dicarbonyl compounds was carried out in the presence of HEDP. Also based on NMR studies, a chemism of these reactions, which is stepwise, is proposed. It has been established that the optimal conditions for the synthesis of glycoluryls and hydantoins using HEDP are: temperature 80°C-90°C, 40-20 minutes, and the ratio of urea and HEDP is 1:1. In all cases, the remaining aqueous filtrate containing HEDP after the reaction can be reused for other cycles synthesis of glycoluril and other compounds, because HEDP is not converted during the reaction. 相似文献
949.
950.
Izmaylov AF Staroverov VN Scuseria GE Davidson ER Stoltz G Cancès E 《The Journal of chemical physics》2007,126(8):084107
We have recently formulated a new approach, named the effective local potential (ELP) method, for calculating local exchange-correlation potentials for orbital-dependent functionals based on minimizing the variance of the difference between a given nonlocal potential and its desired local counterpart [V. N. Staroverov et al., J. Chem. Phys. 125, 081104 (2006)]. Here we show that under a mildly simplifying assumption of frozen molecular orbitals, the equation defining the ELP has a unique analytic solution which is identical with the expression arising in the localized Hartree-Fock (LHF) and common energy denominator approximations (CEDA) to the optimized effective potential. The ELP procedure differs from the CEDA and LHF in that it yields the target potential as an expansion in auxiliary basis functions. We report extensive calculations of atomic and molecular properties using the frozen-orbital ELP method and its iterative generalization to prove that ELP results agree with the corresponding LHF and CEDA values, as they should. Finally, we make the case for extending the iterative frozen-orbital ELP method to full orbital relaxation. 相似文献