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EN
This paper addresses the historical environmental impact of Bydgoszcz’s ‘Old Gasworks’, located on Jagiellońska Street on the Brda River-one of Poland’s oldest and longest-operating gas production facilities. Municipal gas derived from dry coal distillation served both municipal and industrial purposes until 1973. However, the production process, marked by significant nuisances, particularly affected the ground and water environment. Pollutants, primarily organic compounds such as aromatic hydrocarbons, including PAHs (polycyclic aromatic hydrocarbons), and BTEX hydrocarbons (benzene, toluene, ethylbenzene, xylenes), phenol and mineral oil, entered the environment through equipment failures, leaks, and the improper storage of wastewater and technological waste. One of the major sources of contamination was inadequately executed construction activities related to the dismantling of installations and the liquidation of sewage and waste storage tanks. This paper presents the findings of a comprehensive study focusing on hydrocarbon concentrations in groundwater at the ‘Old Gasworks’ in Bydgoszcz and proposes effective methods for treating the water environment.
PL
Próbki gleby zanieczyszczonej mieszaniną paliw węglowodorowych poddano działaniu ognia. Po samoistnym zgaszeniu z popiołu wyekstrahowano związki aromatyczne (2-, 3-, 4-, 5- i 6-pierścieniowe). Jako rozpuszczalnik zastosowano wodę demineralizowaną i 3-proc. roztwory wodne 5 pianotwórczych środków gaśniczych. Ekstrakt analizowano metodą chromatografii gazowej sprzężonej ze spektrometrią mas (GC-MS). Stopień wymywania węglowodorów z gleby przy użyciu środków gaśniczych wynosił 28,79–51,05%, a przy użyciu wody 1,52%.
EN
A fire was induced on 5 soil samples impregnated with a mixt. of hydrocarbon fuels. After self-extinguishing the fire, soil samples were extd. with demineralized water,n-C6 H14 and 5 types of 3% aq. solns. of foam-forming extinguishing agents. The content of 2, 3, 4, 5 and 6 ring arom. hydrocarbons was detd. in the exts. by using GC-MS. The extn. degree of hydrocarbons from soil was 28.79–51.05% and 1.52% with extinguishing agents and water, resp.
EN
Petrochemical-derived products may enter the soil with rainwater, sewage, and during equipment failures. Due to their physicochemical properties, they cause a threat to the environment and change the properties of engineering-geological land. In the study, samples of soil originating from the vicinity of 20 gas stations in the city of Kielce have been examined. The following soil parameters were determined: pH, Hh, exchangeable cations, content of CaCO3, Corg and PAH. The amount of PAHs and their composition varied depending on numerous factors such as the soil quality as well as location and degree of exploitation of petrol stations.
EN
In many foundries, the requirements placed on castings production have risen mainly over the few years. Further trends in recent years have been the ever increasing level of automation and introduction of new alloys, especially composites. On the other hand, the foundry environment has become increasingly difficult because is used many organic binders. Environmental regulations will be further tightened up. These processes are pursued at national, European and global level. Conformity with emission limits is becoming increasingly difficult. The problem is emission of aromatic hydrocarbons, phenol, odours and other harmful compounds to environment. The main purpose of many companies is reduction of this toxins. The new cold-box systems (based on phenolic resins) try to reduce the emission by introducing into the resin structure silicate modifiers. Research presented of this article evaluate the effectiveness of these methods. The results show comparison of two resins ("without" and "with" silicate modifier) for assessment of emission of harmful aromatic hydrocarbons and phenol.
EN
A simple and effective cooling device based on a thermoelectric cooler was applied to cool the SPME fiber. The device was used for quantitative extraction of aromatic hydrocarbons in the air. Several factors such as coating temperature, extraction temperature and relative humidity in the laboratory setting were optimized. Comparison of the results between the cold fiber SPME (CF-SPME) and NIOSH 1501 method on standard test atmosphere indicated a satisfactory agreement. The CF-SPME and SPME method were also compared. The results revealed that CF-SPME has the most appropriate outcome for the extraction of aromatic hydrocarbons from the ambient air. The cold fiber SPME technique showed good results for several validation parameters. Under the optimized conditions, the limits of detection (LOD) and the limits of quantification (LOQ) ranged from 0.00019 to 0.00033 and 0.0006 to 0.001 ng ml−1 , respectively. The intra-day relative standard deviation (RSD) showed ranging from 4.8 to 10.5%.
EN
The presence of made grounds containing industrial waste materials in the natural environment presents a potential ecological threat. Therefore, in the present study we examined the indirect effects of selected made grounds on the aquatic flora and fauna. The subject of the study were aqueous extracts from made grounds containing metallurgical slags and their effect on the survival of the crustacean daphnia (Daphnia magna) and the inhibition of growth of the plant duckweed (Lemna minor). Due to the fact that duckweed is also used for phytoremediation, the solution after the contact with the plant was assessed for changes of toxicity using the toxicological enzymatic bioassay employing bacteria (Allivibrio fischeri). It was found that the extracts of made grounds adversely affect both the survival of the crustaceans and the growth of plants, however, despite the inhibition of the growth of duckweed it has the ability to phytoremediate contaminants present in the made grounds.
EN
The feasibility of using laccase from Trametes versicolor for degradation of aromatic hydrocar-bons has been investigated. In the experiments, benzo[a]pyrene (BaP) was used. Laccase was immobilized onto mesoporous micelle-templated silica such as Santa Barbara Amorphous (SBA-15) and hexagonal mesoporous silica (HMS) as well as corresponding amino-functionalized supports. The best results were obtained for SBA-15 mesoporous silica however the HMS support could be as well considered for this type of application. The reusability of laccase immobilized into both silica supports was tested for five reaction cycles and the conversion reached about 70% of the initial value.
EN
No-bake process refers to the use of chemical binders to bond the moulding sand. Sand is moved to the mould fill station in preparation for filling of the mould. A mixer is used to blend the sand with the chemical binder and activator. As the sand exits the mixer, the binder begins the chemical process of hardening. This paper presents the results of decomposition of the moulding sands with modified urea-furfuryl resin (with the low content of furfuryl alcohol below 25 % and different activators: organic and inorganic) on a quartz matrix, under semi-industrial conditions. Investigations of the gases emission in the test foundry plant were executed according to the method extended in the Faculty of Foundry Engineering (AGH University of Science and Technology). Article presents the results of the emitted chosen aromatic hydrocarbons and loss on ignition compared with the different activators used to harden this resin. On the bases of the data, it is possible to determine the content of the emitted dangerous substances from the moulding sand according to the content of loss on ignition.
EN
The aim of this study was to determine the effectiveness of the removal of selected 7 PAHs (naphthylene, acenaphthene, fluorene, phenanthrene, pyrene, benzo (a) anthracene, chrysene) from coke wastewater. Hydrogen dioxide is used as the oxidant at doses of 50, 100, 300, 600, 900, 1000, 2000 mg/L. PAH removal efficiency was based on the initial concentration in the wastewater coke. Examined changes in general indicators of organic pollu- tants such as COD, TOC in the process. TOC conversion ratio were determined at COD. amounted to 6.11. On the basis of the parameters CODobl and TOC the optimal dose for the oxidation process was from 600 to 1000 mg/L. Quantitative and qualitative analysis of PAH was performed using a gas chromatograph mass spectrometer. The optimal dose for 7 PAHs was 300 mg/L. PAH removal from wastewater 73% for the 3-ring compounds and 67% for the 4-ring hydrocarbons.
10
Content available remote Analysis of selected compounds in the surface water of lake Oleckie Wielkie
EN
The paper presents the results of research on the content of 16 PAH, selected anions and heavy metals in samples collected from Lake Oleckie Wielkie. The samples were collected at seven locations around the lake within about 15 m from the shore in November 2012. The highest total concentration of 16 PAH (68.58 μmol dm−3) was found in water sample no. 7, and the lowest in water samples no. 1, 4 and 5. The obtained results do not exceed the levels of standards accepted in Poland for the surface water. The analysis of collected water samples, performed with the isotachophoresis method, showed a low content (less than 4 mg dm−3) of the analyzed anions: nitrates(V), nitrates(III), chlorides, sulphates(VI), sulphates(IV), phosphates(V) and hydrocarbonates(IV), as well as a low content of the analyzed heavy metals.
PL
W pracy przedstawiono metodykę badań ksylenu technicznego w celu jego charakterystyki zgodnie z wymaganiami rejestracyjnych systemu REACH. W badaniach zastosowano technikę chromatografii gazowej z detektorem płomieniowo-jonizacyjnym (GC-FID) oraz w sprzężeniu ze spektrometrią mas (GC-MS) Chromatografia gazowa umożliwia wykonanie dwóch fundamentalnych oznaczeń tego typu mieszaniny - tzn. zbadania czystości mieszaniny oraz identyfikacji i oznaczenia głównych składników mieszaniny -poszczególnych izomerów ksylenu.
EN
The paper presents a method for characterization of technical grade mixed xylene by means of gas chromatography with flame ionization detector (GC-FID) and coupled with mass spectrometry (GC-MS) in terms of REACH registration reąuirements. Gas chromatography allows to perform analysis ofthe two fundamenta! parameters of such type ofmixture i.e. the purity analysis and identification as well as ąuantification of major components ofthe mixture - the isomers ofxylene.
EN
Aromatic hydrocarbons are present in the fossil wood samples in relatively small amounts. In almost all of the tested samples the dominating aromatic hydrocarbon is perylene and its methyl and dimethyl derivatives. The most important biomarkers present in the aromatic fraction are dehydroabietane, siomonellite and retene, compounds characteristic for conifers. The distribution of discussed compounds is highly variable due to such early diagenetic processes affecting the wood as oxidation and the activity of microorganisms. MPI1 parameter values (methylphenanthrene index) for the majority of the samples are in the range of 0.1 to 0.5, which results in the highly variable values of Rc (converted value of vitrinite reflectance) ranging from 0.45 to 0.70%. Such values suggest that MPI1 parameter is not useful as maturity parameter in case of Middle Jurassic ore-bearing clays, even if measured strictly on terrestrial organic matter (OM). As a result of weathering processes (oxidation) the distribution of aromatic hydrocarbons changes. In the oxidized samples the amount of aromatic hydrocarbons, both polycyclic as well as aromatic biomarkers decreases.
PL
Obowiązujące obecnie wymagania jakościowe dla paliw ciekłych są wynikiem wdrożenia do prawa krajowego postanowień Dyrektyw Parlamentu Europejskiego i Rady 2009/30/WE.
EN
Exhaust gas from compression ignition engine fed with oil-water emulsions containing 10 vol. % of water or H2O2 (30 vol. %) water solution in commercial diesel oil have been analysed and the results compared with the composition of flue gas when diesel oil alone was used. The analyses concerned concentrations of NO, total NOx, carbon monoxide, the sum of hydrocarbons as well as volatile organic compounds. When emulsion was used, considerable reduction of nitrogen oxides (however for low engine load only) and slightly lower smokiness of flue gas was reached; on the other hand, it caused higher concentrations of CO, aromatic hydrocarbons and the highest increase, even up to 10-fold, of acetaldehyde concentration, a typical product of incomplete combustion of organic compounds.
PL
Zainteresowanie lotnymi związkami organicznymi, a w szczególności związkami z grupy BTEX, w ostatnich latach znacząco wzrosło. Z uwagi na to, że jednopierścieniowe węglowodory aromatyczne odgrywają znaczącą rolę w chemii atmosfery oraz mają negatywny wpływ na zdrowie człowieka, konieczne jest poznawanie ich losu środowiskowego.
17
Content available remote Relacja pomiędzy wiązaniem wodorowym wspomaganym rezonansem a aromatycznością
EN
Among the so called non-covalent interactions the hydrogen bond (H-bond) is probably the most frequently and the most thoroughly investigated. This is due to the fact that H-bond plays an essential role in many physical, chemical and biochemical processes. The strongest H-bonds are those assisted with additional effects, as for instance the resonance assisted H-bonds (RAHBs). The concept of RAHB was first proposed by Gilli and co-workers in 1989, and with the time it has become one of the most thoroughly investigated aspects from the field of structural chemistry. Originally, the definition of RAHB was directly connected with the resonance effect acting in RAHB motif (either intra- or intermolecular). Many scientists were exploring the phenomena of the RAHB. Thus, some controversies appeared in connection with the extra stabilization of the RAHB if comparing with its "non-resonance-assisted" counterparts. Some authors criticized the original explanation introduced by Gilli et al. and proposed alternative mechanism responsible for the relatively stronger H-bonding in the RAHB motifs. Since the resonance effect accompanying the formation of H-bridge in RAHBs is in fact a π-electron effect, it may interact with other π -electron effects acting in specific molecules, e.g. with substituent effect or aromatic đ -electron delocalization. In this way the mutual interaction between different đ -electron effects may occur, which may influence many physical and chemical properties of molecular systems under consideration, as for instance the strength of RAHB, local aromaticity, proton transfer barrier and many others. In this paper a short review on the current state of knowledge on RAHB will be presented. The special attention will be paid onto the interrelation between RAHB and local aromaticity in derivatives of polycyclic aromatic hydrocarbons.
EN
This study evaluated the influence of contamination with aromatic hydrocarbons on the efficacy of cellulose decomposition with the use of soil cellulolytic microorganisms. In the experiments we used the monoaromatic hydrocarbons rrom BTEX group (benzene, toluene, ethylobenzene and xylene - a mixture) and polycyclic compounds (naphthalene and anthracene) used in the following concentrations: 100, 1.000 and 10.000 mg o kg-1 d.m. of soil. We found out that usually the presence of aromatic hydrocarbons stimulated the cellulolytic activity of soil microflora - the higher activity was noted in the soil contaminated with PAH (anthracene). The percentage of cellulose decomposition was increased along with the increase of monoaromatic hydrocarbon dosage (except toluene); a similar dependence was not noted for polycyclic aromatic hydrocarbons (PAH).
PL
W pracy określano wpływ zanieczyszczenia węglowodorami aromatycznymi na efektywność rozkładu błonnika przy udziale celulolitycznych mikroorganizmów glebowych. W doświadczeniach wykorzystano węglowodory monoarotnatyczne z grupy BTEX (benzen, toluen, etyiobenzen i ksylen - mieszanina) oraz wielopierścieniowe (naftalen i antracen), które stosowano w stężeniach 0. 100, 1000 i 10000 g o kg-1 s.m. gleby. Stwierdzono, że na ogół obecność węglowodorów aromatycznych stymulowała celulolityczną aktywność mikroflory glebowej - większą aktywność odnotowano w glebie zanieczyszczonej naftalenem i antracenem. Procent rozkładu błonnika zwiększał się wraz ze wzrostem dawki węglowodorów monoaromatycznych (z wyjątkiem toluenu); podobnej zależności nie odnotowano dla węglowodorów wielopierścieniowych.
19
Content available remote Phenol biodegradation by Pseudomonas putida PCM2153 [commun.]
EN
Phenol degradation efficiency of Pseudomonas putida PCM2153 free cells was experimentally studied. Bacterial cells were acclimatized to phenol what relied on gradually increasing the phenol concentration in the medium. The highest phenol degradation rate was calculated as approximately 15.2 mgźdm-3źh-1. Investigated strain degraded the phenol at the concentration of 400 mgźdm-3 in 24 h. The result of toxicity analysis showed that acclimatized cells of P. putida PCM2153 are able to survive even at as high concentration of phenol as 3000 mgźdm-3. The obtained result suggests that the analyzed strain can be used for effective treating of high strength phenolic wastewater. Due to resistance of the strain to high phenol concentration it may be applied in bioremediation of exceedingly contaminated sites, especially where dilution of pollutants cannot be implemented.
PL
W doświadczeniu analizowano efektywność rozkładu fenolu przez szczep Pseudomonas putida PCM2135. Komórki bakteryjne zostały poddane adaptacji do wysokich stężeń fenolu, która polegała na stopniowym zwiększaniu jego stężenia w pożywce. Maksymalna szybkość rozkładu fenolu wyniosła 15,2 mgźdm-3źh-1. Badany szczep usunął 400 mg fenolu w ciągu 24 godzin. Przeprowadzone testy toksyczności wykazały, że zaadaptowane komórki P. putida PCM2153 są zdolne do przeżycia w roztworze fenolu nawet o stężeniu 3000 mgźdm-3. Uzyskane wyniki sugerują, że badany szczep może być wykorzystany do efektywnego oczyszczania ścieków charakteryzujących się wysokim stężeniem fenolu. W zawiązku z odpornością szczepu na wysokie stężenia fenolu, może on być wykorzystywany do bioremediacji terenów silnie zanieczyszczonych fenolem, gdzie rozcieńczanie zanieczyszczeń jest niemożliwe.
PL
Celem pracy było opracowanie i wdrożenie w Laboratorium Analiz Chemicznych Instytutu Metalurgii Żelaza metod analitycznych identyfikacji oraz oznaczania zawartości lotnych węglowodorów aromatycznych w odpadach hutniczych, za pomocą chromatografu gazowego sprzężonego ze spektrometrem masowym (HRGC/HRMS). Przedmiotem badań były wzorce z atestowaną zawartością lotnych związków organicznych, rdzenie i formy odlewnicze zarówno przed jak i po procesie odlewania, masy bentonitowe, a także próbki gleby z otoczenia zakładu przemysłowego. Ustalono warunki pracy chromatografu gazowego i spektrometru masowego, opracowano specyficzną metodę przygotowania próbek do oznaczania BTEX oraz sporządzono odpowiednie procedury analityczne.
EN
The purpose of the paper was to develop and implement in the Chemical Analyses Laboratory of the Institute for Ferrous Metallurgy the methods for identification and determination of the content of volatile aromatic hydrocarbons in metallurgical waste using the gas chromatograph coupled with the mass spectrometer (HRGC/HRMS). The subject of the examinations were standards with certified content of volatile organic compounds, cores and casting moulds, both before and after casting, bentonite masses, as well as soil samples taken at the surroundings of the industrial plant. The gas chromatograph and mass spectrometer operating conditions were established, the specific method for sample preparation for BTEX determination was developed, and the relevant analytical procedur as were prepared.
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