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EN
The article takes into consideration technological and ecological aspects of IV generation moulding sands. Investigations concerning an application of biopolymer materials as binders for moulding sands are presented in the paper. These investigations are the continuation of examinations related to applications of various biopolymers as binding agents and to the properties of the moulding sands with biopolymer binders. In the paper there are the researches concerning analyzing gases emitted from moulding sands during heating.
PL
Uniepalniacze są to substancje opóźniające zapłon. Na podstawie piśmiennictwa przedstawiono zagrożenia dla człowieka wynikające z zastosowania tych środków w różnych gałęziach przemysłu.
EN
Flame retardants (FRs) are chemicals which added to materials during or after manufacture, inhibit or even suppress the combustion process due to their thermal stability. Large quantities of FRs are added to the plastic material (resins) in variety of electrical and electronic appliances including television and computer casing. The other uses of these compounds include production of building materials, upholstered furniture, textiles, wall covering, carpets, hydraulic fluids as well as vehicles and aircraft. Taking into account the chemical structure, there are five main groups of FRs: brominated, chlorinated, phosphorous-containing, nitrogen-containing (i.e. melamines) and inorganic compounds. Halogenated compounds, especially polybrominated diphenyl ethers (PBDEs), a class of brominated flame retardants, due to their lipophilic characteristics and persistence have become ubiquitous environmental contaminants. There are indications that PBDEs may affect hormone function acting as endocrine disruption and may be toxic for developing brain. These compounds have been associated with non-Hodgkin's lymphoma in humans, a variety of cancers in rodents and disruption of thyroid hormones balance. Similarly to other persistent halogenated compounds they are also able to affect the xenobiotic metabolizing enzymes activity. PBDEs are now found as residues in sediments, wildlife and human (milk, serum adipose tissue) samples. The predominant congeners in environmental samples, including human specimens are two congeners: 47 and 99. Currently, the estimated daily intake of PBDEs by adult humans is equal 51 ng x day-1 while by breast-fed infants equals 110 ng x day-1.
PL
Zbadano właściwości fizykochemiczne wybranych polichlorowanych pochodnych dibenzodioksyny – PCDD; dibezofuranu – PCDF oraz bifenylu – PCB. Na bazie uzyskanych danych przeprowadzono analize˛ SAR w zakresie toksyczności badanych związków. Dane fizykochemiczne obliczono metodąpółempiryczną, na podstawie struktur pochodnych po ich optymalizacji geometrycznej, za pomoca˛ programu HyperChem. Zgromadzone dane porównywano z miarą toksyczności (TEF) związków. Na podstawie uzyskanych wyników stwierdzono, że analiza SAR na bazie właściwości fizykochemicznych może być prowadzona tylko w grupach związków o podobnej budowie.
EN
A structure-activity relationship (SAR) analysis of toxicity was carried out and physicochemical data of selected polychlorinated derivatives of: dibenzodioxine PCDD; dibenzofurane PCDF; and biphenyl PCB were obtained. The physical and chemical parameters of the examined compounds were calculated by semi-empirical methods from their structures after geometry optimisation by the HyperChem software. The collected data were compared to TEF of the examined compounds. The results show that the physicochemical data can be used in SAR analysis of the groups of similar compounds only. The toxicity of dioxins is weak when log P > 5. The relationships between important hydrophobic parameters (logP, logM, RM and α) and TEF are inversely proportional in each group of compounds. The values of important electrostatic parameters (εHOMO and εLUMO) are directly proportional to TEF. The univariate and bivariate relationships calculated as the coefficients of correlation between TEF and the physicochemical parameters of the examined compounds were not significant.
PL
Wykonano 8 tyg. doświadczenie na szczurach zatruwanych ołowiem i kadmem, którym podawano preparaty flawonoidów aronii i tarczycy bajkalskiej. Wykazano ochronne działanie aronii na zmiany patologiczne w wątrobie i nerkach zatruwanych zwierząt.
EN
In a 8-week experiment, rats intoxicated with lead (400 mg/kg foodstuff) and cadmium (100 mg/kg foodstuff) were receiving per os flavonoid extracts of Aronia melanocarpa and Scutellaria baicalensis at 5 mg/kg body weight. The pathomorphological changes in liver and kidneys of the poisoned animals were less evident after treatment with flavonoids of Aronia melanocarpa. The advantageous effect of that extract was confirmed by a slight decrease of free-radical reactions in the chemiluminescent test. After treatment of rats with flavonoids of Scutellaria baicalensis, the protective effect was not observed.
PL
Omówiono polichlorowane dibenzodioksyny (PCDDs) oraz pokrewne im związki. Wskazano na główne źródła ich powstawania oraz omówiono problemy analityczne związane z identyfikacją i oznaczaniem tych związków.
EN
Polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) as well as similar compounds are described and chracterized as a group of environmental pollutants which have been arousing interest only since a short time. The toxicity of the compouds in this group of xenobiotics is compared with that of other compounds generally regarded as highly toxic. The main sources of origin of PCDDs/PCDFs are found in nearly all fields of the technological actions of man. Problems of detection and identification of these compouds extremely difficult in analysis are discussed. These problems are a challenge to even specialists laboratories.
PL
W pracy zwrócono uwagę na szeroki zakres stosowania chemicznych środków ochrony roślin w sadach, co stanowi zagrożenie dla środowiska. W szczególności dotyczy to insektycydów, wśród których dominują nieselektywne, toksyczne preparaty z grupy neurotoksyn. Zjawiskiem niekorzystnym jest także niedobór środków do biologicznego zwalczania. W podsumowaniu, podano wykaz proekologicznych środków ochrony roślin zalecanych do ochrony upraw sadowniczych w Polsce.
EN
In this paper attention was put on a large scale of chemical plant protection in orchards, which cause threats for the environment. It concerns especially insecticides, where nonselective, toxic neurotoxins dominate. As a negative phenomenon, deficiency of biological means of plant protection also occur. The list of recommended pro-ecological plant protection products for fruit growing in Poland is also presented.
PL
Spalanie odpadów komunalnych to jedno z głównych źródeł emisji dioksyn i wynikającego stąd zagrożenia. Rozpoznanie i odpowiednie prowadzenie procesu spalania, zastosowanie współczesnych instalacji redukcyjnych dowodzi, że stężenie dioksyn w stałych i gazowych produktach spalania można istotnie ograniczyć i zachować jego poziom w zakresie wymagań prawnych.
EN
Within the group of organochlorine, posing a positive danger the natural environment, the most interesting, controversial and objectionable for ecologist are dioxins. In professional journals the name „dioxins" is a simplification which commonly refers to a certain group of organic chemical compounds, or, to be more precise, their derivatives called polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The latest research has confirmed the existence of yet another group of similiar character polybrominated and polyfluorinated. Though other sources of industrial dioxins emission exist their first and foremost sources are incineration processes, in particular the processes of municipal, hospital and other toxic and chemical waste incineration. The compounds mentioned above, but all their isomers tetrachlorodibenzodioxin (TCDD), tetrachlorodibenzofuran (TCDF) - are highly toxic and lack of emission control may prove highly hazardouss for health and natural environment. The paper discusses a number of issues connected with dioxin emission during incineration of solid and gaseous municipal waste. A balance of the transport of dioxins between their source (i.e. the waste), through the process of their incineration and recombination, to the final stage their presence in solid and gaseous incineration products. Following that European legislature on dioxin emission is discussed together with the presentation of state-of-the-art installations for reducing the amount of dioxins in exhausted gasses. Most of the research has been based on author's own observations and research done while taking active part in operation of selected waste incineration plants. The remaining data have been gathered from reference papers on current experiments carried out in European waste incineration plants. Summing up, the paper maintains that the incineration of municipal waste in state-of-the-art installations conforming to emission norms does not endanger the natural environment with dioxins emitted in exhaust gasses. This danger is, however, present in the solid incineration products due to high concentration of dioxins there. Operators are fully aware of this fact and attempt to counteract it. The awareness of presence of dioxins emitted in the process of waste incineration should be decisive factor while choosing technology and installation, which fitted appropriate cleanup equipment will guarantee level of dioxin emission safe for the environment and conforming to the norms of dioxin emission.
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