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951.
Bioelectricity Production from Soil Using Microbial Fuel Cells 总被引:2,自引:0,他引:2
Agnieszka Wolińska Zofia Stępniewska Arletta Bielecka Jakub Ciepielski 《Applied biochemistry and biotechnology》2014,173(8):2287-2296
Microbial fuel cells (MFCs) are a device using microorganisms as biocatalysts for transforming chemical energy into bioelectricity. As soil is an environment with the highest number of microorganisms and diversity, we hypothesized that it should have the potential for energy generation. The soil used for the study was Mollic Gleysol collected from the surface layer (0–20 cm). Four combinations of soil MFC differing from each other in humidity (full water holding capacity [WHC] and flooding) and the carbon source (glucose and straw) were constructed. Voltage (mV) and current intensity (μA) produced by the MFCs were recorded every day or at 2-day intervals. The fastest and the most effective MFCs in voltage generation (372.2?±?5 mV) were those constructed on the basis of glucose (MFC-G). The efficiency of straw MFCs (MFC-S) was noticeable after 2 weeks (319.3?±?4 mV). Maximal power density (P max?=?32 mW m?2) was achieved by the MFC-G at current density (CD) of 100 mA m?2. Much lower values of P max (10.6–10.8 mW m?2) were noted in the MFC-S at CD of ca. 60–80 mA m?2. Consequently, soil has potential for production of renewable energy. 相似文献
952.
Agnieszka Bogdanowicz Henryk Foks Katarzyna Gobis Anna Kędzia Ewa Kwapisz Andrzej Olczak Marek L. Główka 《Journal of heterocyclic chemistry》2013,50(3):544-550
2‐Bromo‐4‐(pyrrolidin‐1‐yl)pyridine‐3‐carbonitrile obtained from 2‐(1,3‐bis(pyrrolidin‐1‐yl)allylidene)malononitrile has been used as a substrate for the synthesis of new cyanopyridine derivatives: 2‐methoxy, 2‐phenoxy, 2‐aminoethylthio, and 2‐thioxo. 4‐(Pyrrolidin‐1‐yl)‐2‐thioxo‐1,2‐dihydropyridine‐3‐carbonitrile 7 in reaction with suitable alkyl and aminoalkyl halides gave respective sulfides. All synthesized compounds were evaluated for their antimicrobial activity against 26 aerobic and anaerobic bacteria. Determined minimal inhibitory concentration values ranged from 6.2 to 100 µg/mL. Derivatives 1 , 3 , 4 , 6 , and 12 were the most active compounds. 相似文献
953.
954.
Lucie Smoláková árka Botková Libor apek Peter Priecel Agnieszka Soltysek Martin Kout Lenka Matějová 《催化学报》2013,34(10):1905-1913
Ni/Al2O3 catalysts for oxidative dehydrogenation(ODH) of ethane were prepared by impregnation of Al2O3 with nickel acetate or nickel nitrate,and by mechanical mixing of NiO and Al2O3.The Ni-based catalysts were characterized by N2 adsorption-desorption,X-ray diffraction,diffuse reflectance UV-visible diffuse reflectance spectroscopy,and temperature-programmed reduction of hydrogen.The results showed that formation of crystalline NiO particles with a size of < 8 nm and/or non-stoichiometric NiO species in the Ni/Al2O3 catalysts led to more active species in ODH of ethane under the investigated reaction conditions.In contrast,tetrahedral Ni species present in the catalysts led to higher selectivity for ethene.Formation of large crystalline NiO particles(22-32 nm) over Ni/Al2O3 catalysts decreased the selectivity for ethene. 相似文献
955.
Dr. Jacek Ściebura Dr. Agnieszka Janiak Agata Stasiowska Dr. Jakub Grajewski Dr. Krystyna Gawrońska Prof. Dr. Urszula Rychlewska Prof. Dr. Jacek Gawroński 《Chemphyschem》2014,15(8):1653-1659
Trityl group, Tr, is a molecular dynamic rotor of which the conformation and helicity depend on other groups in the close vicinity. Interactions with another covalently linked Tr group and with other substituents are analyzed in terms of transfer of chirality to the trityl group. Two trityl groups in a molecule can mutually interact at a distance of two, three, or five bonds. Despite its size, a Tr group attached to a cyclohexane or cyclopentane ring through an oxygen or nitrogen atom adopts either an axial or equatorial position, depending on additional stabilizing interactions, such as hydrogen bonding. 相似文献
956.
Małgorzata Lisowska-Kuźmicz Małgorzata Kantor-Boruta Anna Jończyk Małgorzata Jarończyk Agnieszka Ocios-Bębenek Aleksander P. Mazurek Zdzisław Chilmonczyk Maciej Jarosz 《Analytical and bioanalytical chemistry》2014,406(15):3697-3702
A new chromatographic method for the enantioseparation and the determination of (?)-trans-paroxetine and (+)-trans-paroxetine has been developed with the aid of amylose ovomucoid-based chiral stationary phase. The method is faster and five times more sensitive than procedures recommended previously: limit of detection and limit of quantification are 5 and 16 ng/mL, respectively [modified (Ferretti et al. in J Chromatogr B 710:157–164, 1998): 20 and 60 ng/mL]. It was carefully validated and applied for the determination of (?)-trans-paroxetine and (+)-trans-paroxetine in Parogen (Mc Dermott Laboratories Ltd.) and Xetanor (Actavis) coated tablets. Figure
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957.
Bismuth Film Electrodes for Adsorptive Stripping Voltammetric Determination of Sunset Yellow FCF in Soft Drinks
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Agnieszka Królicka Andrzej Bobrowski Jerzy Zarębski Iwona Tesarowicz 《Electroanalysis》2014,26(4):756-765
The bismuth film electrode was used to record well‐developed voltammograms of azo food coloring Sunset Yellow FCF (SY). The employed Bi(III)/HClO4 plating solutions produced very adhesive and mechanically stable films that were applied in both stationary and flow conditions. The influence of the dimensions of the glassy carbon support, plating solution concentration and potential was discussed. The sensitivity of SWV was sufficient to obtain a linear calibration curve for low concentration levels of SY (below 0.1 mg/L; LOD=1 µg/L, linear range 4.4–87 µg/L). The measurements in a flow system were considered as a tool for the determination of relatively high concentrations (>1 mg/L; LOD=300 µg/L, linear range 300–8800 µg/L) of SY. 相似文献
958.
Intermolecular Interactions in Systems Containing Bi(III) – ClO−4 – H2O – Selected Amino Acids in the Aspect of Catalysis of Bi(III) Electroreduction
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Agnieszka Nosal‐Wiercińska 《Electroanalysis》2014,26(5):1013-1023
The paper describes recent results of studies on the accelerating effect of sulfur‐containing protein amino acids and water activity on multistep Bi(III) ion electroreduction at mercury electrode. The catalytic effect of methionine (Mt), cystine (CY) and cysteine (CE) was analyzed based on kinetic and thermodynamic parameters, which correlated with water activity. Investigations of adsorption of those amino acids at the electrode/solution interface provided information for the analysis of the electrical double layer and its influence on the kinetics of the electrode process. The multistep Bi(III) electroreduction process is controlled by the kinetics of active complexes formation, which precedes transfer of consecutive electrons. 相似文献
959.
Maria Lalia-Kantouri Kostantinos Parinos Maria Gdaniec Konstantinos Chrissafis Wieslawa Ferenc Christos D. Papadopoulos Agnieszka Czapik Jan Sarzynski 《Journal of Thermal Analysis and Calorimetry》2014,116(1):249-258
The simultaneous TG/DTG–DTA technique was used for three new cobalt(II) complexes with dipyridylamine (dpamH) and the anion of a 2-hydroxyphenone ligand (phenone), with the general formula [Co(dpamH)2(phenone)]Br, in order to determine their thermal degradation in static air and dynamic nitrogen atmospheres, which was found to be a multi-step decomposition related to the release of the ligand molecules. The complexes were characterized by elemental analyses, FT-IR and UV–Vis spectroscopy, magnetic and conductivity measurements. All structures were determined by X-ray crystallography revealing octahedral coordination of cobalt(II) and monomeric nature of the compounds, [Co(dpamH)2(2-OH-acetophenone)]Br (1), [Co(dpamH)2(2-OH-propiophenone)]Br (2) and [Co(dpamH)2(2-OH, 5-CH3-acetophenone)]Br·EtOH (3). The variable temperature (76–303 K) magnetic susceptibility measurements showed a paramagnetic nature of the complexes, in accordance with their molecular structure. 相似文献
960.
Maciej Sowa Alicja Kazek-Kęsik Agnieszka Krząkała Robert P. Socha Grzegorz Dercz Joanna Michalska Wojciech Simka 《Journal of Solid State Electrochemistry》2014,18(11):3129-3142
Herein, a study of the plasma electrolytic oxidation (PEO) of niobium in an anodising bath composed of potassium silicate (K2SiO3) and potassium hydroxide (KOH) is reported. The effects of the K2SiO3 concentration in the bath and the process voltage on the characteristics of the obtained oxide layers were assessed. Compact, barrier-type oxide layers were obtained when the process voltage did not exceed the breakdown potential of the oxide layer. When this threshold was breached, the morphology of the oxide layer changed markedly, which is typical of PEO. A significant amount of silicon, in the form of amorphous silica, was incorporated into the oxide coatings under these conditions compared with the amount obtained with conventional anodising. This surface modification technique led to an improvement in the corrosion resistance of niobium in Ringer’s solution, regardless of the imposed process conditions. 相似文献