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Poszukując alternatywy dla toksycznych środków ochrony roślin, podjęto badania mające na celu ocenę przydatności nanocząstek srebra syntetyzowanych na drodze redukcji chemicznej do zwalczania grzybów z gatunku Fusarium culmorum. Do badań prowadzonych na terenie województwa małopolskiego pobrano 218 kłosów pszenicy ozimej z objawami fuzariozy. Kłosy po odkażeniu wykładano na podłoże PDA (agar glukozowo-ziemniaczany) i inkubowano w 24oC przez 7 dni. Fragmenty wyrośniętej grzybni przeszczepiano na kolejne szalki Petriego z podłożem PDA w celu izolacji czystych szczepów. Zgromadzono 79 szczepów należących do gatunku Fusarium culmorum. Synteza nanocząstek srebra (Agnano ) przebiegała na drodze redukcji chemicznej z zastosowaniem wybranego stabilizatora. Przeprowadzono badania spektroskopowe w zakresie UV-Vis oraz oceniono morfologię nanocząstek przy użyciu skaningowego mikroskopu elektronowego. Wpływ nanocząstek srebra na wzrost szczepów Fusarium culmorum badano dodając w odpowiednich proporcjach Agnano do pożywki, a następnie zaszczepiając na niej 5 mm fragmenty grzybni, kontrolę stanowiło podłoże bez dodatku nanostruktur. Na podstawie przeprowadzonych analiz stwierdzono grzybobójcze działanie testowanych nanocząstek srebra. Za minimalne stężenie hamujące wzrost szczepów Fusarium culmorum uznano 60 ppm.
The quality of five commercial monocalcium phosphates (MCP) and dicalcium phosphates with natural admixtures of hydrated and dehydrated forms was assessed on the basis of their crystalline phases determined by roentgenographic irradiation, Ca and P contents, and solubility in water, 2% citric acid, 0.4% HCl, and ammonium citrate solutions. The phosphates were used in diets fed between days 1 and 35 of life to 300 Hubbard Flex male broilers, 6 replications (cages) of 10 chickens per treatment. Performance indices, Ca, P and Mg retention, and the concentration of these elements in blood and bone ash, as well as the physical parameters of femur and tibia bones were measured. The content of P in phosphates varied between 17.7% and 23%, their solubility in citric acid and HCl solutions ranged between 89–99%. The roentgenograms indicated that phosphate No. 1 contained pure MCP; No. 2, MCP with admixture of anhydrous dicalcium phosphate (DCP); No. 3, DCP with an admixture of MCP; No. 4, dicalcium phosphate dehydrate (DDCP); No. 5, DDCP with an admixture of DCP. The type of phosphate used in chicken diets did not influence body weight or feed intake. Phosphorous retention, Ca and P in serum, and some bone parameters were better in chickens fed the diet containing pure MCP (P<0.01). Lower concentrations of Ca and P in bones and worse parameters of bone elasticity were found in chickens fed diets containing DDCP with DCP. In the biological experiment, the overall best results were obtained in chickens fed diets containing pure hydrated monocalcium phosphate
Bioleaching and biogenesis are the main outputs from a large group of environmental processes participating in the natural material cycle, used in raw materials processing. Bio-oxidation reactions are the main basis for bioleaching procedures, often participating in parallel leaching processes. During the leaching processes of polycomponent sulphide substrates, the factor of process selection also plays an important role, being in direct relation to the electric properties and galvanic effect occurring between the individual components of the leaching substrate. This work gives a summary of the results of a research focused on the possibilities of using biotechnological procedures for treatment of Slovak sulphide ores. The object of the research is extraction of valuable metals, undesirable admixtures and degradation of crystal lattice of sulphides for subsequent chemical leaching processing of precious metals. The results of experiments on the existence of biogenic processes in situ on waste dumps from exploitation containing residual sulphides are also presented. The processes result in acid mine drainage water generation. These waters are strongly mineralised (over 48 g/L) and of low pH; that is why they are very caustic. The arsenic content (2.558 mg/L) in outflowing waters from old mines is high and over the limits set by the law.
 The rebuilding of the phosphorus cycle can be performed with the use of both biotechnology and chemical technology. This paper presents a review of the phosphorus cycle and the different approaches that can be taken to the recovery of phosphorus from phosphate-rich waste. Critical issues in the phosphorus cycle are also discussed. Methods for the recovery of phosphorus form sewage sludge ash are widely explored and divided into two groups: wet extraction methods and thermochemical methods. Laboratory-scale methods are described, as well as proposed industrial technologies, with particular regard to the possibilities for their implementation in Poland. Phosphorus recovery methods from SSA (sewage sludge ash) in our country seems to be promising due to the increasing number of sewage sludge incineration plants, which could easily supply ash to future recovery installations. For the effective recovery of P from sewage sludge ash, it is essential to make the right choice in determining the appropriate method to use with respect to the particular properties of the ash composition; available. A patented method of phosphorus recovery by acid extraction methods, developed by Cracow University of Technology, results in an efficiency of 80-96% for phosphorus recovery. 3000 to 4000 tons of phosphorus per year can be recycled and introduced back into the environment, that covers around 7% of the total amount of phosphorus ore imported into Poland between 2008 and 2009.
This paper presents a comprehensive and systematic approach to sewage sludge management in both Polish and European Union (EU) legislative systems. It starts with risk, which can be caused by sewage sludge mismanagement. Also, technical aspects and boundaries of utilization and recycling routes are presented. A comparison of national and EU legislation is also presented. The next part is devoted to sewage sludge production, distribution and utilization in Poland. Finally, the influence of sewage sludge treatment and utilization on health and environmental risk in Poland are presented.
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