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  1. 8 Przemysł Chemiczny
  2. 6 Bromatologia i Chemia Toksykologiczna
  3. 5 Chemia i Inżynieria Ekologiczna
  4. 5 International Journal of Occupational Medicine and Environmental Health
  5. 5 Polish Journal of Environmental Studies
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  1. 2 2023
  2. 3 2022
  3. 4 2021
  4. 2 2020
  5. 2 2019
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  1. 5 Zielinska-Psuja B.
  2. 3 Majnusz U.
  3. 3 Namieśnik J.
  4. 3 Wardas W.
  5. 3 Zabiegała B.
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1
Content available remote Izobaryczny proces uwodornienia benzenu
100%
Szarlik S. , Gołębiowski A. , Stołecki K.
Przemysł Chemiczny
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2006
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tom T. 85, nr 8-9
665-667
PL
Opracowano podstawy technologii nowego izobarycznego procesu uwodornienia benzenu i katalizatory dla tego procesu.
EN
A new process of isobaric hydrogenation of benzene and two catalysts were developed. The process is practicable only if a low-activity, selective, and high-S-absorption catalyst is used at Step I of benzene hydrogenation. No existing com. catalyst is suitable. New Ni-Cu catalysts were developed, which are believed to enable Step I temps. to be raised to 260-270°C. Simulations gave catalysts temps. and reactant and product concns. vs. catalyst bed length. Reactor was sized and charged as that used in the CYCLOPOL process. The isobaric process uses less steam (no evapn. of cyclohexane-benzene before Step II), less reactants, a cheaper catalyst, possibly a smaller reactor, and it yields a purer cyclohexane and a higher-pressure steam as compared with the existing process.
2
Content available A novel application of building demolition waste for removal benzene from aqueous solutions
100%
Alquzweeni S. S. , Hassan A. A. , Alkizwini R. S.
Przegląd Naukowy. Inżynieria i Kształtowanie Środowiska
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2021
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tom 30
|
nr 1[91]
3
Content available Benzene and Toluene Removal by Carbon Nanotubes from Aqueous Solution
100%
Bina B. , Amin M. M. , Rashidi A. , Pourzamani H.
Archives of Environmental Protection
|
2012
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tom Vol. 38, no. 1
3-25
EN
The removal of benzene (B) and toluene (T) from aqueous solution by multi walled, single walled, and hybrid carbon nanotubes (MWCNTs, SWCNTs, and HCNTs) was evaluated for a nanomaterial dose of 1 g/l, concentration of 10-100 mg/l, and pH 7. The equilibrium amount removed by SWCNTs (B: 9.98 mg/g and T: 9.96 mg/g) was higher than for MWCNTs and HCNTs. Toluene has a higher adsorption tendency on CNTs than benzene, which is related to the increasing water solubility and the decreasing molecular weight of the compounds. The SWCNTs performed better for B and T sorption than the MWCNTs and HCNTs. Isotherms study based on isofit program indicate that the Generalized Langmuir-Freundlich (GLF) isotherm expression provides the best fit for benzene sorption, and that Brunauer-Emmett-Teller (BET) isotherm is the best fit for toluene adsorption by SWCNT. SWCNTs are efficient B and T adsorbents and possess good potential applications to water and wastewater treatment and maintain water of high quality that could be used for cleaning up environmental pollution.
4
Content available A novel application of building demolition waste for removal benzene from aqueous solutions
100%
Alquzweeni S. S. , Hassan A. A. , Alkizwini R. S.
Przegląd Naukowy Inżynieria i Kształtowanie Środowiska
|
2021
|
tom Vol. 30, No. 1
86--97
EN
A novel application of building demolition waste for removal benzene from aqueous solutions. In this research, demolition waste from buildings has been studied for possible use as benzene removal adsorbent from aquatic solution. The effect of adsorbent dosage, contact time, initial benzene concentration, and initial pH on benzene adsorption capacity have been investigated in the batch adsorption experiments. The adsorption effects initially happened very rapidly and achieved equilibrium within 180 min. Benzene removal was observed to decrease by an increase in the initial concentration of benzene of 300–700 mg·L–1, an increase in the adsorbent dose of 0.4–2.4 g per 100 mL, where an optimum adsorbent dose equal to 1.2 g per 100 mL was found. The potential of adsorption increases with pH 3.0–7.0 to reach the maximum removal efficiency at pH 6.0. The findings showed that equilibrium data were adequately adapted and correlated with the Freundlich isotherm models. The average percentage of the removal at room temperature was about 98%. Results suggest that building demolition waste can be used effectively in industrial wastewater treatment for the removal of aromatic hydrocarbon, benzene, as a low-cost option.
5
Content available Laboratory studies on benzene sorption processes in clay formations
100%
Wołowiec K. , Malina G.
Geology, Geophysics and Environment
|
2015
|
tom Vol. 41, no. 1
43--51
EN
The presented studies focused on benzene sorption mechanisms in the semi-permeable geological formations (aquitards). Clay formations were taken under consideration as not well investigated so far. Natural clay samples artificially contaminated with benzene were used in batch and column experiments to determine benzene partitioning and retardation in the studied clay material, and to reflect natural groundwater flow conditions. Column tests were carried out under controlled water flow conditions and using undisturbed clay samples. Benzene concentrations in tested samples (water and soil) were determined by gas chromatography (GC-FID). The linear sorption isotherm was used to fit the experimental data, as well as calculate the distribution coefficient (K d = 0,042) and the retardation factor (R = 1.21) of benzene in the studied clay material. These parameters are important for mathematical modelling of the fate and transport of benzene through the semi-permeable formations (clays) to assess the associated risk and to prevent groundwater resources from contamination.
6
Content available Effect of Simultaneous Exposure to Benzene and Ethanol on Urinary Thioether Excretion
100%
Mikov I. , Stankov K. , Vasovic V. , Mikov A. , Golocorbin-Kon S. , Mikov M.
International Journal of Occupational Safety and Ergonomics
|
2012
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tom Vol. 18, No. 1
107--111
EN
The toxicity of benzene is not an issue of the past, especially in developing countries. Bone marrow toxicity is demonstrated among workers. In this study, the effect of simultaneous exposure to benzene and ethanol on benzene metabolism in mice was investigated by measuring the excretion of thioethers in urine. Urinary thioether excretion significantly decreased in the mice receiving both benzene and ethanol compared with the animals receiving benzene only. The assay of determining thioethers in urine samples in this study is a simple and low-cost method, thus suitable for routine use, especially in developing countries, not only for benzene,but also for other alkilating agents, which can be found during occupational exposure. Our results suggest that further research is needed to elucidate the mechanisms of decreased urinary excretion of thioether after simultaneous exposure to benzene and ethanol.
7
Content available Chlorinated benzenes and benzene degradation in aerobic pyrite suspension
88%
Pham H. T. , Chihiro I.
Archives of Environmental Protection
|
2019
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tom Vol. 45, no. 1
115--125
EN
The focus of this study is to investigate the applicability of natural mineral iron disulfide (pyrite) in degradation of aromatic compounds including benzene and several chlorinated benzenes (from mono-chlorinated benzene (CB), di-chlorinated benzenes (di-CBs) to tri-chlorobenzenes (tri-CBs) in aerobic pyrite suspension by using laboratory batch experiments at 25°C and room pressure. At first, chlorobenzene was studied as a model compound for all considered aromatic compounds. CB was degraded in aerobic pyrite suspension, transformed to several organic acids and finally to CO2 and Clˉ. Transformations of remaining aromatic compounds were pursued by measuring their degradation rates and CO2 and Clˉ released with time. Transformation kinetics was fitted to the pseudo-first-order reactions to calculate degradation rate constant of each compound. Degradation rates of the aromatic compounds were different depending on their chemical structures, specifically the number and position of chlorine substituents on the benzene ring in this study. Compounds with the highest number of chlorine substituent at m-positions have highest degradation rate (1,3,5-triCB > 1,3-diCB > others). Three chlorine substituents closed together (1,2,3-triCB) generated steric hindrance effects. Therefore 1,2,3-triCB was the least degraded compound The degradation rates of all compounds were in the following order: 1,3,5-triCB > 1,3-diCB > 1,2,4-triCB ≅1,2-diCB ≅CB ≅benzene > 1,4-diCB > 1,2,3-triCB. The final products of the transformations were CO2 and Clˉ. Oxygen was the common oxidant for pyrite and aromatic compounds. The presence of aromatic compounds reduced the oxidation rate of pyrite, which reduced the amount of ferrous and sulfate ions release to aqueous solution.
8
Content available The River System Pollutant Migration in the Context of the Sudden One-Time Discharge with Consideration of the Bottom Sediments Influence (Case of Benzene Migration in the Stryi River, Ukraine)
88%
Kuzyk A. , Karabyn V. , Shuryhin V. , Sushko Y. , Stepova K. , Karabyn O.
Ecological Engineering & Environmental Technology
|
2023
|
tom Vol. 24, iss. 1
46--54
EN
Basing on the mathematical model developed with the account of influence of bottom sediments, the parameters of benzene migration in the river caused by one-time discharge into the Stryi River were investigated. The mathematical model of migration consists of two equations that describe the movement of pollutants in the river system, taking into account the flow rate, diffusion, sorption and desorption of the pollutant by the bottom sediments of the river. The parameters of benzene distribution in the "water-bottom sediments" system were experimentally determined under laboratory conditions. With the help of computer modeling, the temporal and spatial distributions of benzene in water and bottom sediments were obtained. The regularities of benzene concentration change depending on the composition of the bottom sediments of the river have been established. The dependencies can be extrapolated to other river systems and pollutants.
9
Content available Prediction of Benzene Migration Parameters Resulting from Continuous Flow in a Mountain River
88%
Shuryhin V. , Karabyn V. , Kuzyk A.
Ecological Engineering & Environmental Technology
|
2023
|
tom Vol. 24, iss. 8
73--81
EN
Using a mathematical model that includes the influence of bottom sediments, a comprehensive study of the migration of benzene (C6H6) as a result of its continuous release into a mountain river was conducted. The adopted migration model consists of two equations that accurately describe the movement of pollutants within the river system, considering crucial factors such as flow velocity, diffusion, sorption, and desorption by river sediments. Through meticulous laboratory experiments, the distribution parameters that govern the behavior of benzene (C6H6) within the water-sediment system were successfulully determined. Leveraging advanced computer modeling techniques, intricate spatiotemporal profiles illustrating benzene (C6H6) concentrations in both water and sediments were generated. Furthermore, consistent patterns in the fluctuations of benzene (C6H6) concentrations that exhibit strong correlation with the specific composition of river sediments were identified. Importantly, these foundational relationships can be extrapolated to diverse river systems and various categories of pollutants.
10
Content available GIS-based assessment of cancer risk due to benzene in Tehran ambient air
88%
Atabi F. , Mirzahosseini S. A.
International Journal of Occupational Medicine and Environmental Health
|
2013
|
tom 26
|
nr 5
770-779
EN
Objectives: The present study aimed to assess the risk of cancer due to benzene in the ambient air of gas stations and traffic zones in the north of Tehran. The cancer risk was estimated using the population distribution data for benzene levels and the unit risk for benzene proposed by the United States Environmental Protection Agency (US EPA). Material and Methods: Sixteen sampling locations were monitored, once every week, during 5 April 2010 to 25 March 2011. Results: The results showed that the mean annual benzene concentration was 14.51±3.17 parts per billion (ppb) for traffic zones and 29.01±1.32 ppb for outside gas stations. The risk calculated was 1026×10⁻⁶ for gas station 27 and 955×10⁻⁶ for gas station 139. Conclusions: According to our results, the annual benzene level in Tehran ambient air is 2 to 20 times higher than the respective value specified in International Standard (1.56 ppb). Moreover, the results showed a notable increase of cancer risks, ranging from 10% to 56%, for the vicinity population close to the gas stations in comparison to the vicinity population in the traffic zones.
11
Content available remote Technologie zmniejszenia zawartości benzenu w benzynach silnikowych
88%
Borowiec Z.
Przemysł Chemiczny
|
2002
|
tom T. 81, nr 4
223-227
12
Content available Preparation of iron oxide nanocatalysts and application in the liquid phase oxidation of benzene
88%
Lokhat D. , Oliver M. , Carsky M.
Polish Journal of Chemical Technology
|
2015
|
tom Vol. 17, nr 2
43--46
EN
A series of iron oxide nanocatalysts were prepared using an ultrasonically assisted co-precipitation technique. Molybdenum promoted Fe3O4 and Fe2O3 were prepared from the original materials by wet impregnation using a solution of ammonium molybdate. The catalysts were tested in the liquid phase oxidation of benzene at atmospheric pressure and at 60°C using molecular oxygen. Phenol yields between 7% and 14.5% were obtained. The major products were pyrogallol and catechol.
13
Content available SAW Sensor with Langmuir-Blodgett Layer for Detection of Benzene and its Derivatives
88%
Balcerzak A. , Kiełczyński P. , Szalewski M. , Wieja K.
Archives of Acoustics
|
2021
|
tom Vol. 46, No. 1
25--30
EN
Vapors of benzene and its derivatives are harmful and toxic for human beings and natural environment. Their detection has fundamental importance. For this purpose authors propose surface acoustic wave (SAW) sensor with skeletonized layer deposited by Langmuir-Blodgett (L-B) method. This layer was obtained by depositing a binary equimolar mixture of 5-[[1,3-dioxo-3-[4-(1-oxooctadecyl) phenyl]propyl]amino]-1,3-benzenedicarboxylic acid with cetylamine. The skeletonized sensor layer has been obtained by removing cetylamine. Response of this sensor depends mainly of the electrical dipole momentum of molecule. Among the tested compounds, benzene has a zero dipole moment and gives the smallest sensor response, and nitrobenzene has the largest dipole moment and the sensor reacts most strongly to its vapor.
14
Content available remote Preparation of iron oxide nanocatalysts and application in the liquid phase oxidation of benzene
88%
Lokhat D. , Oliver M. , Carsky M.
Polish Journal of Chemical Technology
|
2015
|
tom 17
|
nr 2
43-46
EN
A series of iron oxide nanocatalysts were prepared using an ultrasonically assisted co-precipitation technique. Molybdenum promoted Fe3O4 and Fe2O3 were prepared from the original materials by wet impregnation using a solution of ammonium molybdate. The catalysts were tested in the liquid phase oxidation of benzene at atmospheric pressure and at 60°C using molecular oxygen. Phenol yields between 7% and 14.5% were obtained. The major products were pyrogallol and catechol.
15
Content available Sample Preparation Followed by High Performance Liquid Chromatographic (HPLC) Analysis for Monitoring Muconic Acid as a Biomarker of Occupational Exposure to Benzene
75%
Shahtaheri S. J. , Ghamari F. , Golbabaei F. , Rahimi-Froushani A. , Abdollahi M.
International Journal of Occupational Safety and Ergonomics
|
2005
|
tom Vol. 11, No. 4
377--388
EN
Factors affecting solid phase extraction (SPE) of trans,trans-muconic acid (ttMA), as a benzene biomarker, including sample pH, sample concentration, sample volume, sample flow rate, washing solvent, elution solvent, and type of sorbent were evaluated. Extracted samples were determined by HPLC-UV (high performance liquid chromatography-ultraviolet). The analytical column was C18, UV wave length was 259 nm, and the mobile phase was H2O/methanol/acetic acid run at flow rate of 1 ml/min. A strong anion exchange silica cartridge was found successful in simplifying SPE. There was a significant difference between recoveries of ttMA when different factors were used (p < .001). An optimum recovery was obtained when sample pH was adjusted at 7. There was no significant difference when different sample concentrations were used (p > .05). The optimized method was then validated with 3 different pools of samples showing good reproducibility over 6 consecutive days and 6 within-day experiments.
16
Content available remote Comparison of benzene and its alkylated derivates profiles in car's fuels, engine exhaust gases and in air in the vicinity of communication arteries
75%
Żak M. , Konieczyński J.
Archives of Environmental Protection
|
2008
|
tom Vol. 34, no. 2
3-11
EN
Motorization pollutants, benzene, benzene alkylated derivatives, profiles, car's fuels, engine exhaust gases, air pollution. Abstract: Main sources of emission of benzene and its alkylated derivatives to the atmospheric air, particularly the vehicular ones, are characterized in the paper. Growing use of fuels, especially unleaded gasoline, leads to emission of considerable amounts of these aromatic hydrocarbons. The paper presents and discusses results of determinations of the content of benzene and its alkylated derivatives in engine fuels. Also emission factors of these hydrocarbons from commonly used in Poland types of cars, both with spark- and self-ignition engines, are considered. Profiles of investigated hydrocarbons in fuels and exhaust gases were determined. Respectively compared profiles proved the motor vehicles responsible for main part of the benzene and its alkylated derivatives in air in the vicinity of communication arteries.
PL
W artykule scharakteryzowane zostały główne źródła emisji benzenu i jego pochodnych alkilowych do powietrza atmosferycznego, ze szczególnym uwzględnieniem źródeł motoryzacyjnych. Wzrost zużycia paliw silnikowych, a zwłaszcza benzyn bezołowiowych, prowadzi do emisji dużych ilości tych aromatycznych węglowodorów do powietrza atmosferycznego. W artykule zaprezentowano i omówiono wyniki badań własnych dotyczących określenia zawartości benzenu i jego pochodnych alkilowych w paliwach silnikowych oraz wskaźników emisji tych węglowodorów z powszechnie eksploatowanych w Polsce typów pojazdów samochodowych z silnikami z zapłonem iskrowym (Zl) i zapłonem samoczynnym (ZS). W oparciu o uzyskane wyniki określono profile badanych węglowodorów w paliwach silnikowych i spalinach z silników samochodowych. Porównanie odpowiednich profili dowiodło, że pojazdy samochodowe są głównym źródłem emisji benzenu i jego pochodnych alkilowych w rejonach tras komunikacji samochodowej.
17
Content available Chemizm wód podziemnych w rejonie ujęcia „Lipce” i „Grodza Kamienna” w Gdańsku
75%
Pasierowska B. , Tarnawska E. , Lidzbarski M. , Kordalski Z.
Przegląd Geologiczny
|
2016
|
tom Vol. 64, nr 6
418--426
EN
The article presents the results of groundwater chemistry studies in the area around the “Lipce” and “Grodza Kamienna” intakes in Gdańsk. In the northern part of the “Lipce” intake the groundwater quality has been low for the last few years; therefore it was necessary to pump water from two wells directly into drainage ditches. Currently, the benzene concentration in the groundwater exceeds the maximum permissible limit for drinking water (>1μg/dm3). Groundwater quality is also lowered by the presence of phenol, PAH and vinyl chloride (PVC). The studies showed variability of the benzene and phenol concentrations in the upper and bottom parts of the Holocene-Pleistocene aquifer. Chemical analysis of soil taken from drainage ditches revealed contamination caused by illegal sewage discharge emitted from a nearby factory, producing tar in the past.
18
Content available Benzene exposure among auto-repair workers from workplace ambience: A pioneer study from Pakistan
75%
Kamal A. , Rashid A.
International Journal of Occupational Medicine and Environmental Health
|
2014
|
tom 27
|
nr 5
830-839
EN
Objectives: In Pakistan, the reports on benzene exposure among workers in chemical industries are almost non-existing due to limited research work in the field of exposure science. This study aimed to investigate such exposure in a widely adopted occupation in Rawalpindi city. Material and Methods: In this cross-sectional study, 60 blood samples (N = 20/group) of mechanics (MCs), spray painters (PNs) and control participants (CN) were analyzed. The socio-economic and demographic information of workers and that of workplaces was documented using a short questionnaire. Results: We identified that the workers in spray-painting occupation are highly at risk of benzene exposure. The results showed that PNs were more at risk of exposure to benzene than MCs, and this exposure was significantly correlated with long working hours (r = 0.68, p < 0.001). Moreover, there are several limitations in workplace setups, which need to be addressed in order to mitigate workers health risk in this occupation. In addition to the reckless use of chemicals, other identified predictors of exposure included active and passive smoking, poor workplace hygiene and substandard ventilation. Conclusions: To mitigate workplace exposure, it is necessary to reduce working hours and encourage regular use of self-protective equipments and adoption of proper hygiene in chemical workplaces.
19
On Barrier Formation of Long-Lived Doubly Charged Benzene Dimer
75%
Kryachko E.
Polish Journal of Chemistry
|
2007
|
tom Vol. 81, nr 5-6
833-846
EN
It has recently been demonstrated [J. Am. Chem. Soc., 127, 16824 (2005) Ref. [30]] that a fused carbon–carbon bond appears in the long-lived dicationic states of the benzene dimer to defy the law of Coulomb repulsion between like charges. The present work sheds a light on the formation of a high Coulomb barrier that separates the usual fission reaction pathway on the potential energy surface of the doubly-charged benzene dimer from the fusion one and renders the dicationic benzene dimer with a fused interring bond a substantial lifetime. For this purpose, a high computational levels is invoked in the presentwork to demonstrate that a variety of the lower-energy structures of the benzene dimer cation are mainly determined by their origin, either by the compressed-obtuse or elongated- acute ground-state conformers of the benzene cation radical and also includes two novel saddle homodimers. The latter, being ionized, form the striking patterns on the dicationic potential energy surface yielding thus the Coulomb barrier which is the rate-limiting step in formation of the fused C–C interring bond.
20
Content available Exocrine pancreatic cancer and living near to waste sites containing hazardous organic chemicals, New York State, USA – an 18-year population-based study
75%
Weinstein B. , da Silva A. , Carpenter D. O.
International Journal of Occupational Medicine and Environmental Health
|
2022
|
tom 35
|
nr 4
459-471
EN
ObjectivesThe etiology of exocrine pancreatic cancer (EPC) remains unknown except for family history and smoking. Despite recent medical advances, rates of pancreatic cancer incidence and mortality are increasing. Although existing evidence suggests a potentially causal relationship between environmental chemical exposures and pancreatic cancer, whether residential exposure impacts pancreatic cancer rates remains unknown.Material and MethodsThe authors identified 28 941 patients diagnosed with exocrine pancreatic cancer in New York State exclusive of New York City for the years 1996–2013. Descriptive statistics and negative binomial regression were used in this ecological study to compare pancreatic cancer hospitalization rates among patients who lived in zip codes with hazardous waste sites (HWSs) containing persistent organic pollutants (POPs) and volatile organic pollutants (VOCs) compared with clean zip codes with no identified hazardous waste sites. The authors assessed the effect of selected known and suspected human carcinogens on the EPC hospitalization rates by subgroup analyses.ResultsCompared with the clean sites, the pancreatic cancer hospital discharge rate in the “VOCs without POPs” and “VOCs and POPs” sites, after adjustment for potential confounders were 1.06 (95% CI: 1.03–1.09) and 1.05 (95% CI: 1.01–1.08), respectively. In the analysis by specific chemicals, rate ratios (RR) for the benzene (RR = 1.12) and ethylbenzene (RR = 1.34) in the non-chlorinated VOCs group, trichloroethylene (RR = 1.07) and tetrachloroethylene (RR = 1.11) in the chlorinated VOCs group, chlorinated pesticides (RR = 1.11) and PCBs (RR = 1.05) in the POPs groups were statistically significant (p-values <0.05) compared with clean sites.ConclusionsCompared with the clean sites, the pancreatic cancer hospital discharge rate in the “VOCs without POPs” and “VOCs and POPs” sites, after adjustment for potential confounders were 1.06 (95% CI: 1.03–1.09) and 1.05 (95% CI: 1.01–1.08), respectively. In the analysis by specific chemicals, rate ratios (RR) for the benzene (RR = 1.12) and ethylbenzene (RR = 1.34) in the non-chlorinated VOCs group, trichloroethylene (RR = 1.07) and tetrachloroethylene (RR = 1.11) in the chlorinated VOCs group, chlorinated pesticides (RR = 1.11) and PCBs (RR = 1.05) in the POPs groups were statistically significant (p-values <0.05) compared with clean sites.
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