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排序方式: 共有338条查询结果,搜索用时 296 毫秒
91.
Elena Binkauskiene Albinas Lugauskas Malle Krunks Ilona Oja Acik Vitalija Jasulaitiene Gintautas Saduikis 《Synthetic Metals》2010,160(9-10):906-910
The growth of Chrysosporium merdarium on TiO2 (rutile, anatase) and its possibility to deteriorate the surface were investigated. Treated with fungi and untreated samples of deteriorated TiO2 surfaces were studied by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Microbial deterioration of TiO2 is also discussed. The attachment to the TiO2 surface via metabolic products resulted in the formation of cryptand [2,2,2] complex with Ca2+ ions. According to water contact angle (CA) measurements microbial growth increases the wettability of TiO2 film surfaces. A much more intensive fungal action during microbial treatment on rutile in comparison with that of anatase was observed. A chemical deterioration product, the volatile trimethyl borate, on rutile in exudation of C. merdarium was detected by gas chromatographic–mass spectrometric analysis. 相似文献
92.
93.
Izabela Marcińska Ilona Czyczy?o-Mysza Edyta Skrzypek Maciej T. Grzesiak Franciszek Janowiak Maria Filek Micha? Dziurka Kinga Dziurka Piotr Waligórski Katarzyna Juzoń Katarzyna Cyganek Stanis?aw Grzesiak 《International journal of molecular sciences》2013,14(7):13171-13193
The aim of the study was to assess the role of salicylic acid (SA) and abscisic acid (ABA) in osmotic stress tolerance of wheat seedlings. This was accomplished by determining the impact of the acids applied exogenously on seedlings grown under osmotic stress in hydroponics. The investigation was unique in its comprehensiveness, examining changes under osmotic stress and other conditions, and testing a number of parameters simultaneously. In both drought susceptible (SQ1) and drought resistant (CS) wheat cultivars, significant physiological and biochemical changes were observed upon the addition of SA (0.05 mM) or ABA (0.1 μM) to solutions containing half-strength Hoagland medium and PEG 6000 (−0.75 MPa). The most noticeable result of supplementing SA or ABA to the medium (PEG + SA and PEG + ABA) was a decrease in the length of leaves and roots in both cultivars. While PEG treatment reduced gas exchange parameters, chlorophyll content in CS, and osmotic potential, and conversely, increased lipid peroxidation, soluble carbohydrates in SQ1, proline content in both cultivars and total antioxidants activity in SQ1, PEG + SA or PEG + ABA did not change the values of these parameters. Furthermore, PEG caused a two-fold increase of endogenous ABA content in SQ1 and a four-fold increase in CS. PEG + ABA increased endogenous ABA only in SQ1, whereas PEG + SA caused a greater increase of ABA content in both cultivars compared to PEG. In PEG-treated plants growing until the harvest, a greater decrease of yield components was observed in SQ1 than in CS. PEG + SA, and particularly PEG + ABA, caused a greater increase of these yield parameters in CS compared to SQ1. In conclusion, SA and ABA ameliorate, particularly in the tolerant wheat cultivar, the harmful effects and after effects of osmotic stress induced by PEG in hydroponics through better osmotic adjustment achieved by an increase in proline and carbohydrate content as well as by an increase in antioxidant activity. 相似文献
94.
Estimated human health risks from exposure to recreational waters impacted by human and non-human sources of faecal contamination 总被引:3,自引:0,他引:3
This work was conducted to determine whether estimated risks following exposure to recreational waters impacted by gull, chicken, pig, or cattle faecal contamination are substantially different than those associated with waters impacted by human sources such as treated wastewater. Previously published Quantitative Microbial Risk Assessment (QMRA) methods were employed and extended to meet these objectives. Health outcomes used in the analyses were infection from reference waterborne pathogens via ingestion during recreation and subsequent gastrointestinal (GI) illness. Illness risks from these pathogens were calculated for exposure to faecally contaminated recreational water at the U.S. regulatory limits of 35 cfu 100 mL−1 enterococci and 126 cfu 100 mL−1Escherichia coli. The probabilities of GI illness were calculated using pathogen dose-response relationships from the literature and Monte Carlo simulations. Three scenarios were simulated, representing a range of feasible interpretations of the available data. The primary findings are that: 1) GI illness risks associated with exposure to recreational waters impacted by fresh cattle faeces may not be substantially different from waters impacted by human sources; and 2) the risks associated with exposure to recreational waters impacted by fresh gull, chicken, or pig faeces appear substantially lower than waters impacted by human sources. These results suggest that careful consideration may be needed in the future for the management of recreational waters not impacted by human sources. 相似文献
95.
Only 7 of the sample with 20 video recorders passed the impulse test without any failure. Almost all failures observed were located in the primary part of the power supply. Typically the radio interference suppression capacitors failed and/or internal fuses were blowing. Although the damage is rather small and limited to a few components, a rather expensive repair is required in any case. Since the radio interference suppression capacitors are the weakest point in the insulation system, either their quality has to be improved or some series impedance has to be used for suppression of the transients 相似文献
96.
Susanna M. Früh Philipp R. Spycher Dr. Maria Mitsi Melanie A. Burkhardt Prof. Dr. Viola Vogel Dr. Ingmar Schoen 《Chembiochem : a European journal of chemical biology》2014,15(10):1481-1486
A straightforward strategy is presented for the site‐specific incorporation of fluorophores or reactive probes into the extracellular matrix (ECM) protein fibronectin (Fn) by using the enzyme‐catalyzed transamidation by activated factor XIII. Characterization by SDS‐PAGE, western blotting, absorption measurements, mass spectrometry, and stepwise photobleaching for labeling quantification at the single‐molecule level showed that the labeling was efficient and restricted to the N‐terminal tails. The introduction of labels did not interfere with Fn fibrillogenesis, as verified by the incorporation of fluorescently labeled Fn into ECM and manually pulled Fn fibers. Site‐specific incorporation of an azide was used to create a template for bioorthogonal click chemistry reactions in a second bioconjugation step, thus offering versatile modification and application possibilities in the context of matrix biology and tissue engineering. 相似文献
97.
Andrzej Lewandowski Agnieszka ?widerska-Mocek Ilona Acznik 《Electrochimica acta》2010,55(6):1990-10350
LiMn2O4 was examined as a cathode material for lithium-ion batteries, working together with a room temperature ionic liquid electrolyte, obtained by dissolution of solid lithium bis(trifluoromethanesulfonyl)imide (LiNTf2) in liquid N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (MePrPipNTf2), with the formation of a liquid LiNTf2-MePrPipNTf2 system. The Li/LiMn2O4 cell was tested by galvanostatic charging/discharging and by impedance spectroscopy. The LiMn2O4 cathode showed good cyclability and Coulombic efficiency in the presence of 10 wt.% of vinylene carbonate (VC) as an additive to the ionic liquid. The flash point of the LiNTf2-MePrPipNTf2-VC(10%) electrolyte was estimated to be above 300 °C. 相似文献
98.
The standard activity-based anorexia procedure provides rats with access to a running wheel while restricting their access to dry food. This can produce reduced food intake and progressive weight loss. Using this procedure, in the present study (Experiment 1) the authors found changes in drinking patterns both in the period of high activity preceding food access and during the feeding period. Varying the procedure by providing wet mash (Experiment 2) or by prior adaptation to a drinking schedule (Experiment 3) prevented the self-starvation effect. These results indicate the importance of drinking when analyzing the effect of recent activity on food intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
100.
Gergely Forgács Mohammad Pourbafrani Claes Niklasson Mohammad J. Taherzadeh Ilona Sárvári Hováth 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(2):250-255
BACKGROUND: Because of its extreme toxicity for microorganisms, the limonene content of citrus wastes (CWs) has been a major obstacle to the conversion of CWs to biofuels. The main objective of this study was to develop a new process for the utilization of CWs that can be economically feasible when the supply of CW is low. RESULTS: Steam explosion pre‐treatment was applied to improve the anaerobic digestibility of CWs, resulting in a decrease of initial limonene concentration by 94.3%. A methane potential of 0.537 ± 0.001 m3 kg?1 VS (volatile solids) was obtained during the following batch digestion of treated CWs, corresponding to an increase of 426% compared with that of the untreated samples. Long‐term effects of the treatment were further investigated by a semi‐continuous co‐digestion process. A methane production of 0.555 ± 0.0159 m3 CH4 kg?1 VS day?1 was achieved when treated CWs (corresponding to 30% of the VS load) were co‐digested with municipal solid waste. CONCLUSION: The process developed can easily be applied to an existing biogas plant. The equipment cost for this process is estimated to be one million USD when utilizing 10 000 tons CWs year?1. 8.4 L limonene and 107.4 m3 methane can be produced per ton of fresh citrus wastes in this manner. Copyright © 2011 Society of Chemical Industry 相似文献