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This study was undertaken in order to determine the effects of the constant magnetic field (CMF) on the effectiveness of dairy wastewater treatment under anaerobic conditions. It demonstrated that increasing the value of the magnetic flux in the analyzed range resulted in an increasing effectiveness of the fermentation process. Magnets with induction of 0.38 [T] elicited significant changes in the analyzed parameters of methane fermentation. The magnetic field (MF) was observed to positively affect the sedimentation process of anaerobic sludge, reduced COD concentration in the effluent, and biogas production rate. In the most effective variant, the content of suspended matter in the treated wastewaters was reduced by 26.1% and the effectiveness of COD removal increased by 14.0%, compared to the variant without the application of the physical factor. Magnetic induction of 0.431 caused significant changes in the analyzed parameters of the methane fermentation process.
The aim of the study was to determine the expression of mannose-sensitive and mannose-resis- tant adhesins by agglutination of cattle, sheep, goat, rabbit, horse, and chicken red blood cell assay, and curli fimbriae by Congo red binding assay among 341 E. coli strains isolated from 51 milk samples of clinically recognized bovine mastitis. Curli fimbriae expression within biofilms created on an inert surface was also investigated. To determine whether curli fimbriae are expressed both in conditions optimal for their production and in conditions resembling the host organism, the study was conducted in anaerobic atmosphere at 37CC, and at room temperature in aerobic atmosphere. The results demonstrated that although the E. coli isolates examined were deprived of mannose-sensitive and mannose-resistant adhesins they were able to produce curli fimbriae in both aerobic and anaerobic conditions at room and higher temperature, indicating that these adhesins may be involved in the pathogenesis of bovine mastitis.
The objective of this study was to evaluate and compare the biodegradability and biodegradation rates of ‘single-use' plastic bags available on the market and labeled as degradable/biodegradable. The test was carried out under both aerobic and anaerobic conditions. The project length was 20 months. The biodegradation results in the laboratory conditions demonstrate that none of the degradable/ biodegradable bags showed visual changes and/or were broken into pieces and none of them experienced any disintegration or degradation. The cellulose filter paper (CFP) completely degraded after 10 days in the aerobic conditions and after 5 month in the anaerobic conditions, implying that the conditions required for biodegradation to occur in a sampling environment were present.
By this study, thirty rice varieties were evaluated for anaerobic flooding tolerance using the direct sowing method. Phenolic profiles of strong and weak tolerant varieties were identified and compared based on HPLC chromatograms. The germination rates and shoot heights of rice were recorded for calculating the seedling vigor, which indicate the tolerant ability of rice in flooding condition. The results revealed a high variation of germination rate (10.01 to 100%), shoot height (0.35 to 78.17 mm) and seedling vigor (0.05 to 72.83). There was a high correlation between (r = 0.71) germination rate in 5 cm and 10 cm flood. Phenolic and flavonoid contents of the strong tolerant cultivar significantly and proportionally increased in the flooding levels (5 cm and 10 cm). There was a total difference in terms of number of phenolic acids found in the strong and weak tolerant varieties. In particular, six phenolic acids (gallic acid, catechol, caffeic acid, syringic acid, vanillin, and ellagic acid) were only identified with high concentration in the strong tolerant cultivar. The findings suggest that the phenolics presented in the strong tolerant varieties probably have a certain function in response and adaptation to anaerobic flooding condition. Further researches on exogenous application of these phenolic acids to increase the flooding tolerant level of rice should be continued at both green house and field treatments.
The effects on human erythrocytes of water-derived radicals generated by X-rays were studied under anaerobic conditions and in the presence of oxygen. Erythrocyte damage was estimated on the basis of the reduced GSH and MetHb content in the erythrocytes, the -SH group content in the membrane proteins and the amount of K+ released from the erythrocytes. The results obtained show that the level of reduced GSH was the most sensitive indicator of erythrocyte damage by X-rays followed by the efflux of K+. The processes of GSH oxidation took place most rapidly under air. At a dose of 100 Gy, the level of GSH fell to about 50%, whereas under argon and N2O to about 75% and 65%, respectively. A slight increase in the efflux of K+ was observed in preparations irradiated under air. However, when erythrocytes were irradiated under argon and N2O, the loss of K+ occurred at a dose 8-times higher. Changes in the remaining parameters occurred at considerably higher doses. On the basis of the results obtained one can say that oxygen is a factor increasing the toxicity of OH radicals towards erythrocytes; however, e-aq present in the system can cause a decrease in damage to certain cellular components.
This article focuses on the diatom assemblages and geochemical composition of sediment cores retrieved from the Pomeranian Bay. We also discuss similarities and differences in the diatom assemblages and the palaeogeographic development of nearby regions. Our main objective was to determine the characteristics and rate of the Littorina transgression in the Pomeranian Bay area. Sediments were divided into units based on differences in the distribution of diatom ecological groups and in geochemical ratios, such as Mg/Ca, Na/K and Fe/Mn. This study identified lacustrine sediments deposited during the time of the Ancylus Lake. This lacustrine-period sedimentation took place in a shallow lake under aerobic conditions. The record of the onset of marine environment dates to 8900–8300 cal BP and corresponds to the Littorina transgression. After about 8300 cal BP, sedimentation took place in a deeper marine environment with higher biogenic production and anaerobic conditions. The abrupt appearance of marine diatom species and increased geochemical salinity indicators reflect the large impact of the Littorina transgression on the Pomeranian Bay environment.
Większość znanych populacji mikroorganizmów wykształciła uzdolnienia adhezyjne prowadzące do wytwarzania biofilmu, będącego swoiście niepowtarzalnym mikroekosystemem. Badania koncentrowały się na dynamice adhezji i tworzeniu biofilmu w warunkach beztlenowych przez złoże metanogenne. Opracowano metodę umożliwiającą szacowanie liczby metanogennych archebakterii na podstawie technik mikroskopowych. Identyfikację metanogenów oparto na autofluorescencji koenzymów F420 i F430. W przeprowadzonych eksperymentach powstawanie biofilmu badano na płytkach polistyrenowych, zanurzonych w beztlenowym reaktorze wypełnionym złożem fluidalnym. Badana płytka była częściowo zanurzona w złożu granulowanym, a częściowo w supernatancie nad złożem. Początkowo liczba komórek metanogennego biofilmu wynosiła 4,4 x 104 cm-2 po 6 godz. kolonizacji, a następnie wzrosła do 1 x 107 cm-2 w 27 dobie kolonizacji. Biofilm zawierający więcej bakterii metanogennych szybciej powstawał w części płytki zanurzonej w supernatancie niż w tej części, która była zanurzona w złożu granulowanym. Przełomowym momentem w tworzeniu biofilmu była 21. doba, po której agregaty (mikrokolonie) znacznie się powiększały oraz zaczynała rosnąć ilość archebakterii metanogennych.
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