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Recently, increased interest in the application of various biosorbents in metal ions removal has been observed. The paper presents a systematic characterization of new and commonly abundant low-cost bio- sorbents: above-ground plant parts of wheat straw and grass. Cr(III) was chosen as a model sorbate. The effect of the most significant process parameters (temperature, pH, initial concentration of Cr(III) ions on kinetics, as well as temperature and pH) on biosorption equilibrium was studied. Biosorption was found to be a quick process. The equilibrium was reached within 10-20 minutes. Biosorption capacity of the studied sorbents was intermediate when compared with other sorbents of plant origin ca. 20 mg/g, but since these materials are commonly abundant and of minimal cost, it is possible to improve wastewater treatment ef­ficiency by increasing the concentration of the sorbent. The kinetics of the process in the case of both biomaterials was described with pseudo-second order equation and the equilibrium of biosorption by wheat straw was described with the Freundlich equation and by grass with the Langmuir model. The above equations were chosen to achieve the best consistency of experimental data with the model results. Also, the mechanism of biosorption was investigated, and was determined to be physical adsorption. The paper also discusses the possible methods of utilization of metal-laden biomass, including non-de­structive elution with the regeneration of the biosorbent and ashing as the method of destruction and further concentration of metal.
The article discusses the possibility of the use of algal products, obtained by different methods – extraction (traditional solvent extraction, supercritical fluid extraction, extraction assisted by microwave) and homogenization, in the cultivation of plants. Algal extracts were discussed for their use as potential plant growth biostimulants and the homogenates as formulations for seed treatment. The work is focused on the possibility of using primarily macroalgae from the Baltic Sea basin (in many seaside resorts constitute a waste due to eutrophication) as raw material for the extraction/homogenization. Examples of the research (laboratory – germination tests and field trials) on the impact of algal preparations on the plant growth were presented. Literature data indicate that the algae based products increase the content of micro-, macroelements, chlorophyll in the cultivated plants, as well as their length and weight. Therefore, in the future, they may complement the range of products available on the market.
W pracy przedstawiono procesy biosorpcji i bioakumulacji jako metody wiązania składników mineralnych o znaczeniu paszowym do biomasy organizmów żywych. Jako materiał biologiczny wiążący pierwiastki wybrano algi. Określono ich skład mikroelementowy. Podkreślono ich korzystną charakterystykę paszową, niskie koszty produkcji oraz zdolność wiązania kationów i anionów.
In the present work hair mineral analysis of 110 individuals was carried out to determine environmental exposure based on the distance from a subject’s residence to a pollutant source. The subjects were asked to fill in a questionnaire concerning their place of living in the city of Wrocław (lower Silesia, Poland), which was divided in 12 sectors. The content of minerals in hair was determined by ICP-OES and ICP-MS technique in a laboratory certified by the Polish Centre for Accreditation and ILAC-MRA (No. AB 696). The results were elaborated statistically. Each person served as the experimental unit. Post-hoc comparisons were made by Tukey's test and the Spjotvoll/Stolin test. Results were considered significantly different when p<0.1. The differences in the content of As were statistically significant between IV-V regions (p=0.0182), IV-VII (p=0.0720), and IV-XII (p=0.0586). In the case of Cd, statistically significant differences were found between II and XII region (p=0.0377). Hair has been found to be a valuable indicator of environmental pollution in Wrocław. The highest content of Al was found in sector VII, As – IV, Cd – II, Hg – VIII, Ni – V, and Pb – IX. The explanation could be the vicinity to a heat and power generating plant and a non-ferrous metals plant or other industrial units, as well as interactions between elements in a human organism. Additionally, statistically significant differences between Ni content (p=0.0591) in hair of males and females were found. These results showed that hair mineral content reflected exposure to elements from the environment.
In the present work, the effects of hair type (weak/strong, greasy/normal/dry, presence of dandruff) and cosmetic treatments (using hair dryer, anti-dandruff shampoos) on hair mineral composition was discussed. The application of hair mineral analysis was exemplified by identification of exposure to elements from deodorants. Hair was sampled from 155 individuals who were asked to fill out a questionnaire. The elemental composition of hair was determined by ICP-OES (macroelements and major microelements) and ICP-MS (minor microelements, toxic elements, and other trace elements). Mercury was analyzed by AAS Mercury Analyzer. The results were elaborated statistically by Statistica 8.0. Statistical significance of differences was detennined by U Mann-Whitney test (p<0.05, p<0.1). For elements, the content of which differed between the groups, the reference ranges were elaborated, as were values within the 10th and 90th percentiles. Healthy and strong hair not dried with a dryer contained statistically significantly more K and La and less Co and Ca than destroyed, weak, dried hair and hair with dandruff. In hair with dandruff, statistically higher levels of Hg were found. The results of hair mineral analysis showed that Zn and Se were deposited on hair cuticle exogenously from medicated anti-dandruff shampoo from active ingredients. This technique was used to assess dermal exposure from deodorants. Individuals who used stiff, which contains the compound Zr as antiperspirant, contained 3 to 5 times higher levels of this element than those who used deo roll-on or spray, respectively.
The aim of the present work was to evaluate the mercury content in hair of inhabitants of Wrocław, in southwestern Poland. On the basis of a questionnaire and analysis of hair by atomic absorption spectroscopy, it was possible to indicate the sources of mercury exposure. The mean mercury level in hair of the whole population (n=321) was 0.203±0.181 mg·kg⁻¹. The content of mercury in hair of subjects who consumed fish exceeded the upper limit of reference value, which was 0.397 mg·kg⁻¹. Subjects who declared consumption of fish, honey, and mouldy cheese, contained statistically more mercury: 60.5%, 35.4%, and 37.8%, respectively, than those who did not eat these types of food. It was noticed that there was no effect from the place of residence, the presence of pollution emitters, gender, age, weight, height, presence of amalgam fillings, hair dyeing, and smoking cigarettes on mercury content in hair.
In order to obtain a value-added product from the removal and processing of waste algal biomass, it is essential to elaborate on cost-effective methods of their utilization. Composting appears to be one of the methods of obtaining a natural fertilizer. This paper demonstrates the results of a study where the biomass of seaweed (Fucus sp.) has been co-composted with ecological hay, grass, sawdust, and spent mushroom substrate for three months. The utilitarian properties of the new natural products (compost and compost extract) were examined in germination tests on Lepidium sativum. Three groups were compared: the control group treated with distilled water, and two experimental groups: one treated with seaweed extract and the other fertilized with algal compost. Results showed that the addition of compost and compost extract contributed to the increase in plant length and mass. Moreover, the biomass fertilized with new products was rich in micro- and macroelements (in particular B, Fe, Cu, Zn, Ca, K, S). Utilization of algal biomass for agricultural and horticultural purposes could be benefi cial for environmental protection in that it might help remove waste biomass from coastal areas and from the point of view of the economy by resulting in the production of value-added natural fertilizers and biostimulants (extracts). The latter could help reduce the use of chemical fertilizers and could help to improve physicochemical properties of the soil, thus producing an enhanced seed yield.
Oceniono zawartość rtęci i selenu w mleku surowym pochodzącym od krów z rejonów uprzemysłowionych (LGOM i GOP) oraz ekologicznie czystych (Kotlina Kamiennogórska). Średnie zawartości Hg byty niskie i nie różniły się statystycznie istotnie między poszczególnymi rejonami. Najwyższą koncentrację Se stwierdzono w rejonie Kotliny Kamiennogórskiej, a najniższą w rejonie GOP. Różnice między rejonami były statystycznie istotne (p< 0,05). Współczynnik korelacji między stężeniem Se i Hg wyniósł r = 0,207 i był statystycznie nieistotny.
We assessed the effectiveness use of the new NKSMg fertilizer on the germination of rapeseed (Brassica napus L. var. napus). The fertilizer was produced on the basis of protein hydrolysate from processing of poultry feathers. The whole process is based on the digestion of feather waste by acidic hydrolysis, adjusting pH of the reaction medium, and then enriched in select nutrients. The method allows the production of liquid fertilizers that can be used in soil and foliar applications. Pot experiments have shown that the use of NKSMg fertilizer based on protein hydrolysate of keratin had a significant effect on the increase of plant biomass. The contents of nitrogen, phosphorus, potassium, and magnesium in plants increased by 76.2, 5.20, 37.3, and 29.6%, respectively, compared to unfertilized plants. The use of fertilizer also significantly modified the contents of manganese and zinc in tested plants. Technology of production of fertilizers based on protein hydrolysate is currently implemented by Intermag Co., Polish leader in the manufacture of fertilizers, growth stimulators, and other preparations designed for professional agriculture and horticulture.
The metodology of a determination of some biometals content, i.e. chromium, cobalt, manganese, nickel and iron in Saccharomyces cerevisiae yeasts using UV-VIS spectrophotometer was worked out. An accuracy and precision of chosen analytical meth­ods was determined. The comparison of results obtained with spectrometric ICP-AES method was conducted. Differences of mean values of results between those methods for analysed elements were +10.52, +8.11, -15.79, +1.33, +13.89, and +7.48 %, respectively. It was demonstrated that the UV-VIS spectrophotometric method may be successfully ap­plied in analytical studies concerning a determination of microelements content in en­riched yeasts biomass.
The paper presents results of research concerning an assessment of bioaccumulation of copper, manganese and zinc in Lohmann Brown layer hens (5 groups of 12 hens in each). Using ICP-MS method the concentration of these elements was determined in the content and shell of eggs, whole blood and in feathers of hens. Feeding was based on all-mash feed mixture J-297 type with a content of Cu – 21.8, Fe – 200.8, Mn 140.5 mg⋅kg-1, but in particular groups the contribution of organic and inorganic forms of these 3 microelements was different. Content of Zn in the mixture was 86 mg⋅kg-1 (zinc oxide). Microelements in the amounts of: Cu – 10, Fe – 40 and Mn – 80 mg⋅kg-1 were separately introduced to the control and to the test mixtures by using special premixes. In the control version, inorganic forms of these elements were used in a premix (copper sulfate, iron sulfate and manganese oxide), while in the experimental version they appeared in the organic form, i.e. Saccharomyces cerevisiae yeasts enriched with the three elements. In the experimental mixtures the contribution of organic forms of microelements was for Cu – 47, Fe – 20 and Mn – 58%. Content of the premix in a mixture was 0.5%. Yeasts contained: Fe – 33.9, Mn – 35.4, and Cu – 22.7 mg⋅kg-1 d.m. Content of yeasts in the mixtures did not exceed 0.4%. Application of organic forms of copper caused a significant increase in copper concentration in the egg content and shell, in blood and in feathers in the group receiving organic- Cu, which proves better availability of copper from organic forms compared to copper sulfate. Introduction of organic forms of iron and manganese to feed did not cause any significant changes in the content of these metals in eggs, blood and feathers of hens, except the organic-Mn group (the level of Mn in feathers was significantly higher in feathers compared to the control group). Organic forms of copper, manganese and iron did not result in any interactions with respect to Zn although an antagonistic influence of Cu (organic- Cu group) and synergistic of Mn (organic-Mn group) in the egg content was observed.
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