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81.
Iterative operations on microdroplets and continuous monitoring of processes within them; determination of solubility diagrams of proteins 总被引:1,自引:0,他引:1
ME Dolega S Jakiela M Razew A Rakszewska O Cybulski P Garstecki 《Lab on a chip》2012,12(20):4022-4025
We demonstrate a technique for controlling the content of multiple microdroplets in time. We use this system to rapidly and quantiatively determine the solubility diagrams of two model proteins (lysozyme and ribonuclease A). 相似文献
82.
Andrzej Kudelski Marcin Pisarek Agata Roguska Marcin Hodyski Maria Janik‐Czachor 《Journal of Raman spectroscopy : JRS》2012,43(10):1360-1366
Silver nanoparticles deposited on various ‘inert’ porous materials (mainly Al2O3 and TiO2) are often used as substrates for surface‐enhanced Raman scattering (SERS) measurements. In this study, we used the sputter deposition technique to cover tubular arrays of Al2O3 and TiO2 with Ag nanoparticles. Raman spectra of pyridine (as a probe molecule) and of two selected dyes (5‐(4‐dimethylaminobenzylidene)rhodanine and 5‐(4‐(dimethylamino)benzylidene)‐3‐(3‐methoxypropyl)rhodanine) adsorbed on fabricated Ag/TiO2‐n/Ti and Ag/Al2O3‐n/Al substrates were measured. We found that the SERS spectra of pyridine adsorbed on Ag nanoparticles deposited on an Al2O3‐n/Al substrate are distinctly different from those measured for an Ag/TiO2‐n/Ti composite. Similar effects were observed for dyes adsorbed on the surface of both composites. The spectral differences between two kinds of composites (Ag/TiO2‐n/Ti and Ag/Al2O3‐n/Al) are discussed in terms of (1) the modified electronic structure of the Ag nanoparticles due to their interaction with different substrate materials and (2) the different atomic topology of the metal particles thus deposited on the surfaces of the substrates. Composite samples were also studied with the aid of scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) to reveal their characteristic morphological and chemical features. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
83.
Monika Skwira Agata Jakóbik-Kolon Jerzy Ciba 《Central European Journal of Chemistry》2012,10(2):300-304
A soil incubation and shot-term plant growth experiment was conducted to study the effect of ferruginous mineral application
on exchangeable Al immobilization. The mineral containing mainly siderite was mixed at various rates with A-horizon soil and
incubated at 80% humidity for 45 days. Following the incubation, a short-term plant growth test was carried out using mung beans. The ferruginous mineral application into tested soil resulted in a reduction of the exchangeable aluminum concentration
and soil acidity. An increase in root growth and stalk length, as well as a general improvement of plant condition was observed
in the case of ferruginous mineral application. This observation was confirmed by chemical analysis of roots and stalks. The
greatest amount of essential elements: calcium and magnesium and the lowest amount of aluminum were determined in green part
of mung beans sown in the soil with addition of 2% ferruginous mineral.
相似文献
84.
85.
Ivana Bochicchio Ettore Laserra Agata Longobardi Enrico Mazziotti 《Ricerche di matematica》2012,61(2):219-230
This work is focused on the geometrical and physical characteristics of the class of reference frames associated to harmonic coordinates. Precisely, we express in relative form the harmonicity conditions and consider the so called ??spatially harmonicity?? of a reference frame in spherical symmetry. The initial data problem is then analyzed in polar coordinates and the obtained results are applied to special cases of exact solutions. 相似文献
86.
Nazar Trotsko Jakub Krl Agata Siwek Monika Wujec Urszula Kosikowska Anna Malm 《Heteroatom Chemistry》2012,23(1):117-121
By the reaction of hydrazides of 4‐(4‐halogenophenyl)‐4H‐1,2,4‐triazol‐3‐yl‐sulfanyl acetic acid with isothiocyanate, 1‐acyl‐4‐substituted thiosemicarbazide derivatives ( 7–19 ) were obtained. The cyclization of compounds ( 7–19 ) in the presence of 2% NaOH led to the formation of compounds ( 20–26 ) containing two 1,2,4‐triazole rings connected by a methylenesulfanyl group. The new compounds were tested for their in vitro antimicrobial activity. Some of the tested compounds ( 9, 12, 18, 21, 22 ) showed activity against the reference strains of Gram‐positive bacteria with the MIC (minimal inhibitory concentration) = 125 to >1000 μg/mL. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:117–121, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20758 相似文献
87.
In a natural way we can “lift” any operation defined on a set A to an operation on the set of all non-empty subsets of A and obtain from any algebra (A, Ω) its power algebra of subsets. In this paper we investigate extended power algebras (power algebras of non-empty subsets with one additional
semilattice operation) of modes (entropic and idempotent algebras). We describe some congruence relations on these algebras
such that their quotients are idempotent. Such congruences determine some class of non-trivial subvarieties of the variety
of all semilattice ordered modes (modals). 相似文献
88.
Wojciech Kicinski Jakub P.Sek Agata Kowalczyk Sylwia Turczyniak-Surdacka Anna M.Nowicka Slawomir Dyjak Boguslaw Budner Mikolaj Donten 《Journal of Energy Chemistry》2022,(1):296-308
An extensive analysis of iron-nitrogen-carbon(Fe-N-C)electrocatalysts synthesis and activity is presented concerning synthesis conditions such as initial Fe content,pyrolysis temperature and atmosphere(inert N2,reducing NH3,oxidizing Cl2 and their sequential combinations)and the influence of an external magnetic field on their performance in oxygen reduction reaction(ORR).Thermosetting porous polymers doped with FeCl3 were utilized as the Fe-N-C catalysts precursors.The pyrolysis temperature was varied within a 700-900℃range.The temperature and atmosphere of pyrolysis strongly affect the porosity and compositi on of the resultant Fe-N-C catalysts,while the in itial amount of Fe precursor shows much weaker impact.Pyrolysis under NH3 yields materials similar to those pyrolyzed under an inert atmosphere(N2).In contrast,pyrolysis under Cl2 yields carbon of peculiar character with highly disordered structure and extensive microporosity.The application of a static external magnetic field strongly enhances the ORR process(herein studied in an alkaline environment)and the enhancement correlates with the Fe content in the Fe-N-C catalysts.The Fe-N-C materials containing ferromagnetic iron phase embedded in N-doped microporous carbon constitute attractive catalysts for magnetic field-aided anion exchange membrane fuel cell technology. 相似文献
89.
Michal Nowak Wieslaw Tryniszewski Agata Sarniak Anna Wlodarczyk Piotr J. Nowak Dariusz Nowak 《Molecules (Basel, Switzerland)》2022,27(11)
Hydroxyl radical (•OH) scavenging and the regeneration of Fe2+ may inhibit or enhance peroxidative damage induced by a Fenton system, respectively. Plant polyphenols reveal the afore-mentioned activities, and their cumulative net effect may determine anti- or pro-oxidant actions. We investigated the influence of 17 phenolics on ultra-weak photon emission (UPE) from a modified Fenton system (92.6 µmol/L Fe2+, 185.2 µmol/L EGTA (ethylene glycol-bis(β-aminoethyl-ether)-N,N,N′,N,-tetraacetic acid) and 2.6 mmol/L H2O2 pH = 7.4). A total of 8 compounds inhibited (antioxidant effect), and 5 enhanced (pro-oxidant effect) UPE at all studied concentrations (5 to 50 µmol/L). A total of 4 compounds altered their activity from pro- to antioxidant (or vice versa) along with increasing concentrations. A total of 3 the most active of those (ferulic acid, chlorogenic acid and cyanidin 3-O-glucoside; mean UPE enhancement by 63%, 5% and 445% at 5 µmol/L; mean UPE inhibition by 28%, 94% and 24% at 50 µmol/L, respectively) contained catechol or methoxyphenol structures that are associated with effective •OH scavenging and Fe2+ regeneration. Most likely, these structures can determine the bidirectional, concentration-dependent activity of some phenolics under stable in vitro conditions. This is because the concentrations of the studied compounds are close to those occurring in human fluids, and this phenomenon should be considered in the case of dietary supplementation with isolated phenolics. 相似文献
90.
Agata Zaremba Katarzyna Waszkowiak Dominik Kmiecik Anna Jdrusek-Goliska Maciej Jarzbski Krystyna Szymandera-Buszka 《Molecules (Basel, Switzerland)》2022,27(10)
This study aimed to determine the use of selected vegetables (pumpkin, cauliflower, broccoli, carrot) as carriers of potassium iodide (KI) and potassium iodate (KIO3) by determining changes in iodine content under various conditions of impregnation as the degree of hydration, impregnated sample temperature, and impregnation time. The influence of these conditions on iodine contents in vegetables after their fortification and storage (21 °C/230 days) was analyzed. The results showed that all selected vegetables could be efficient iodine carriers. However, the conditions of the impregnation process are crucial for fortification efficiency, particularly the degree of hydration and the temperature of the impregnated samples before drying. The results showed that the lowest iodine content was in samples fortified at 4 °C and 1:4 hydration. On the other hand, the highest reproducibility of iodine was for the following fortification conditions: temperature of −76 °C and hydration of 1:1. The studies confirmed the higher stability of iodine in KIO3 form compared to KI. To increase recovery of the introduced iodine in the product after drying, using the conditioning step at 4 °C is not recommended. We recommend freezing vegetables immediately after the impregnation process 相似文献