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排序方式: 共有439条查询结果,搜索用时 15 毫秒
101.
Zlata Kelar Tu
ekov Luk Vacek Richard Krumpolec Jakub Kelar Miroslav Zemnek Mirko ernk Filip Ri
ka 《Molecules (Basel, Switzerland)》2021,26(4)
The plasma-activated gas is capable of decontaminating surfaces of different materials in remote distances. The effect of plasma-activated water vapor on Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli biofilm contamination was investigated on the polypropylene nonwoven textile surface. The robust and technically simple multi-hollow surface dielectric barrier discharge was used as a low-temperature atmospheric plasma source to activate the water-based medium. The germicidal efficiency of short and long-time exposure to plasma-activated water vapor was evaluated by standard microbiological cultivation and fluorescence analysis using a fluorescence multiwell plate reader. The test was repeated in different distances of the contaminated polypropylene nonwoven sample from the surface of the plasma source. The detection of reactive species in plasma-activated gas flow and condensed activated vapor, and thermal and electrical properties of the used plasma source, were measured. The bacterial biofilm decontamination efficiency increased with the exposure time and the plasma source power input. The log reduction of viable biofilm units decreased with the increasing distance from the dielectric surface. 相似文献
102.
Coordination of a pyridine-pyrazole-based PNN(H) ligand to RhI produces a family of neutral ( 1 ) and cationic ( 2Cl ) RhI complexes. Deprotonation of the parent Rh chloride complex with LiNiPr2 results in formation of a dinuclear LiCl bridged species 3 bearing a pyrazolate fragment. Complexes 1 , 2Cl and 3 were tested as precatalyst for the dehydrocoupling of amine boranes. All complexes studied show activity for the formation of cyclic oligomers with N-methylcyclotriborazane as the main product. Base activation of the neutral Rh chloride complex 1 produces catalyst systems that are significantly more active than the parent system, suggesting that dehydrohalogenation of the Rh chloride precatalyst 1 is one of the key steps for catalyst formation. 相似文献
103.
Helmut Piazena Jamlec de la Vega Marin Kerstin Gommel Amelie Lupp Cora Roehlecke Mirko Mehner Richard H. W. Funk 《Photochemistry and photobiology》2016,92(3):475-487
Exposures of the skin with electromagnetic radiation of wavelengths between 670 nm and 1400 nm are often used as a general treatment to improve wound healing and reduce pain, for example, in chronic diabetic skin lesions. We investigated the effects of water‐filtered infrared A (wIRA) and of narrow‐band IR‐A provided by a light‐emitting diode LED (LED‐IR‐A) irradiation in vitro on 3T3 fibroblast cultures under defined conditions with and without glyoxal administration. Glyoxal triggers the formation of advanced glycation end products, thereby mimicking a diabetic metabolic state. Cell viability and apoptotic changes were determined by flow cytometry after vital staining with Annexin V, YO‐PRO‐1 and propidium iodide (PI), and by SubG1 assay. Mitochondrial function and oxidative stress were examined by vital staining for radical production, mitochondrial membrane potential (MMP) and the ratio of reduced‐to‐oxidized glutathione (GSH/GSSG). The metabolic state was monitored by a resazurin conversion assay. The numbers of apoptotic cells were reduced in cultures irradiated with wIRA or LED‐IR‐A. More mitochondria showed a well‐polarized MMP after wIRA irradiation in glyoxal damaged cells. LED‐IR‐A treatment specifically restored the GSH/GSSG ratio. The immediate positive effects of wIRA and LED‐IR‐A observed in living cells, particularly on mitochondria, reflect the therapeutic benefits of wIRA and LED‐IR‐A. 相似文献
104.
Morganti A Becagli S Castellano E Severi M Traversi R Udisti R 《Analytica chimica acta》2007,603(2):190-198
A method was developed for the quantitative determination of cations and anions in Antarctic ice cores at μg L−1 and sub-μg L−1 levels by ion chromatography (IC), after ultra-clean decontamination procedures. Strict manipulation and decontamination procedures were used in sub-sampling, in order to minimise sample contamination. Na+, NH4+, K+, Mg2+ and Ca2+ were determined by 12-min isocratic elution (H2SO4 eluent). Contemporaneously, in a parallel device, F−, MSA (methanesulfonic acid), Cl−, NO3− and SO42− were analysed in a single 12-min run with multiple-step elution using Na2CO3/NaHCO3 as eluent. Melted ice samples were pumped from their still-closed containers (polystyrene accuvettes with polyethylene caps), shared between the two ion chromatographic systems, online filtered (0.45 μm Teflon membrane) and pre-concentrated (anions and cations pre-concentration columns) using a flow analysis system, thus avoiding uptake of contaminants from the laboratory atmosphere. Sensitivity, linear range, reproducibility and detection limit were evaluated for each chemical species. Anion or cation detection limits ranged from 0.01 to 0.15 μg L−1 by using a relatively small sample volume (1.5 mL). Such values are significantly lower than those reported in literature for almost all the components. These methods were successfully applied to the analysis of cations and anions at trace levels in the Dome C ice core. The composition of the atmospheric aerosol for the last 850 kyr was reconstructed by high-resolution continuous chemical stratigraphies. Concentration trends in the last nine glacial-interglacial climatic cycles were shown and briefly discussed. 相似文献
105.
106.
107.
Azra ulovi Marijana Popovi Franko Bur
ul Vedrana ike uli Sandra Marijan Mirko Ru
i Nikolina Anelkovi Ivica Blaevi 《Molecules (Basel, Switzerland)》2022,27(23)
Glucosinolates (GSLs) from Sysimbrium officinale and S. orientale were analyzed qualitatively and quantitatively by their desulfo-counterparts using UHPLC-DAD-MS/MS. Eight GSLs were identified in S. officinale, including Val-derived (glucoputranjivin) and Trp-derived (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin) as the major ones followed by Leu-derived (Isobutyl GSL), Ile-derived (glucocochlearin) and Phe/Tyr-derived (glucosinalbin). Different S. orientale plant parts contained six GSLs, with Met-derived (progoitrin, epiprogoitrin, and gluconapin) and homoPhe-derived (gluconasturtiin) as the major ones, followed by glucosinalbin and neoglucobrassicin. GSL breakdown products obtained by hydrodistillation (HD) and microwave-assisted distillation from S. officinale, as well as isopropyl isothiocyanate, as the major volatile in both isolates, were tested for their cytotoxic activity using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Generally, all volatile isolates showed similar activity toward the three cancer cell lines. The best activity was shown by isopropyl isothiocyanate at a concentration of 100 µg/mL after 72 h of incubation, with 53.18% for MDA-MB-231, 56.61% for A549, and 60.02% for the T24 cell line. 相似文献
108.
M. Chem. Caterina Brandmayr Dipl.‐Chem. Mirko Wagner Dr. Tobias Brückl Dr. Daniel Globisch Dr. David Pearson M. Sc. Andrea Christa Kneuttinger Dipl.‐Chem. Veronika Reiter Dr. Antje Hienzsch Dipl.‐Biol. Susanne Koch M. Sc. Ines Thoma Dipl.‐Chem. Peter Thumbs Dr. Stylianos Michalakis Dr. Markus Müller Prof. Dr. Martin Biel Prof. Dr. Thomas Carell 《Angewandte Chemie (International ed. in English)》2012,51(44):11162-11165
109.
Caterina Brandmayr Mirko Wagner Tobias Brückl Daniel Globisch David Pearson Andrea Christa Kneuttinger Veronika Reiter Antje Hienzsch Susanne Koch Ines Thoma Peter Thumbs Stylianos Michalakis Markus Müller Martin Biel Thomas Carell 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(44):11324-11328
110.
Mirko Primc 《Central European Journal of Mathematics》2013,11(2):197-225
We construct bases of standard (i.e. integrable highest weight) modules L(Λ) for affine Lie algebra of type B 2 (1) consisting of semi-infinite monomials. The main technical ingredient is a construction of monomial bases for Feigin-Stoyanovsky type subspaces W(Λ) of L(Λ) by using simple currents and intertwining operators in vertex operator algebra theory. By coincidence W(kΛ0) for B 2 (1) and the integrable highest weight module L(kΛ0) for A 1 (1) have the same parametrization of combinatorial bases and the same presentation P/I. 相似文献