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1 - Zeolite catalyzed alkylation of toluene by alcohol
F. Sheikhoslamy M. Yari K. AhzanVapor-phase methylation of toluene using methanol and its isopropylation with 2-propanol has been investigated ina down flow reactor under atmospheric conditions using N2 carrier over a series of surface modified andunmodified ZSM-5 (Si/Al= 60-170) loaded with H3PO4, di أکثرVapor-phase methylation of toluene using methanol and its isopropylation with 2-propanol has been investigated ina down flow reactor under atmospheric conditions using N2 carrier over a series of surface modified andunmodified ZSM-5 (Si/Al= 60-170) loaded with H3PO4, differing in the external surface treatment of the zeolites.The feed molar ratios of toluene/methanol and toluene/2-propanol were varied over a wide range (8-0.125), andthe optimum feed ratio of toluene/alcohol was less than 0.5 in both cases. Space velocity employed in toluenemethylation reported as WHSV (toluene) = 1.2114, and the space velocity employed in toluene isopropylationreported as WHSV (toluene) = 0.8 III. The methylation reactions were carried out in the temperature range of 623-773 K, and the isopropylation reactions were carried out in the temperature range of 483-583 K. Atmosphericpressures was maintained in all runs. Catalysts containing 0-4.9 wt.% P were prepared using modified andunmodified ZSM-5 zeolites, and their catalytic performance for vapor-phase alkylation of toluene with methanoland 2-propanol were investigated. The optimum phosphorous content for methylation was 2.1 wt.% P which wasgreater than the optimum phosphorous loading for isopropylation (0.7 wt.% P) تفاصيل المقالة -
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2 - The effect of Environmental exposure to some chemical solvents on DPPC as important component of lung surfactant: an ab initio study
M. Monajjemi S. Afsharnezhad J. Yousefi M.R. Jaafari B. Honarparvar M. Mirsadraiee T. Abdolahi S. Ghadri A. Nikosade S.A. BadieeyanOne of the main components of lung alveoli is surfactant. DPPC (Dipalmitolphosphatidylcholine) is thepredominant lipid component in lung surfactant that is responsible for lowering surface tension in alveoli in thisarticle. We used a very approximate model with computat أکثرOne of the main components of lung alveoli is surfactant. DPPC (Dipalmitolphosphatidylcholine) is thepredominant lipid component in lung surfactant that is responsible for lowering surface tension in alveoli in thisarticle. We used a very approximate model with computational method of Ab initio to describe the interactionsbetween DPPC as important component of lung surfactant and some chemical solvents such as Benzene,Toluene, Heptane, Acetone and Ethanol which cause Lung injuries that contribute to respiratory distress such asARDS. The effect of these solvents on the conformation and disordering DPPC head group has beeninvestigated with calculation at the Hatree-Fock level using the 6-31G basis set with Onsager continuumsalvation, GAIO and frequency models. In concern with conformational energy, Water could be the mostsuitable solvent for DPPC. It could be in polar medium DPPC conformer becomes additionally stabilized byintermolecular ionic and hydrogen bond interactions with polar neighboring molecules. On the other hand, thisstudy shows that Ethanol has the most effect on conformation and lipid disorder DPPC head group of lungsurfactant in our model. تفاصيل المقالة -
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3 - Copper Nanoparticles as efficient catalyst for the transesterification of p -ketoesters
A.R. Abbaspour P. MoaveniTransesterification, one of the most effective methods for ester synthesis, is usually conducted under acid or basicconditions. Although quite a few methods have been reported for transesterification, they are not general as far asp-ketoesters are concerned. Some of the أکثرTransesterification, one of the most effective methods for ester synthesis, is usually conducted under acid or basicconditions. Although quite a few methods have been reported for transesterification, they are not general as far asp-ketoesters are concerned. Some of these methods used toxic, expensive reagents and in relatives large amount. Inthis research, transesterification reaction six types P-ketoesters achieved in present of Cu powder and Cunanoparticles as catalyst and P-ketoesters prepared using this method. Copper Nanoparticles is an efficient catalystfor the transesterification of p-ketoesters with several kinds of alcohols, leading to good yields with highselectivity. تفاصيل المقالة -
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4 - جداسازی باکتری های تجزیه کننده تولوئن از خاک پتروشیمی اصفهان
عباس اخوان سپهی الهه ناظر باقر یخچالی محمدرضا ناظرتولوئن یکی از محصولات اصلی پتروشیمی است که به علت سمیت بالا، جهش زایی، سرطان زایی و اثرات مخرب بر زاد و ولد یکی از مواد آلوده کننده رایج محیط زیست می باشد که در اثر نشت مــواد ســوختی، حلال یا شیمیایی باعث آلـودگی محیط زیست می شود. روش های مختلفی برای حذف این ماده از خا أکثرتولوئن یکی از محصولات اصلی پتروشیمی است که به علت سمیت بالا، جهش زایی، سرطان زایی و اثرات مخرب بر زاد و ولد یکی از مواد آلوده کننده رایج محیط زیست می باشد که در اثر نشت مــواد ســوختی، حلال یا شیمیایی باعث آلـودگی محیط زیست می شود. روش های مختلفی برای حذف این ماده از خاک وجود داردکه یکی از بهترین و آسان ترین روش ها، روش زیستی است. قارچ ها و باکتری های هوازی وبی هوازی جمعیت میکروبی غالب در تجزیه تولوئن هستند. سویه ای مفید تر است که توانایی تجزیه تولوئن را در غلظت بالا دارا باشد. در این مطالعه 6 سویه باکتری ازخاک اطراف مجتمع پتروشیمی اصفهان جدا شدند. این سویه هااز تولوئن به عنوان منبع کربن و انرژی استفاده نمودند و به این منظور در معرض غلظت 100-1% تولوئن قرار گرفتند. یکی از سویه ها توانست تا50% غلظت تولوئن رشد کند و در نتیجه بیشترین رشد را داشته باشد. این سویه توسط رنگ آمیزی گرم، تست های بیو شیمیایی و تکنیک sequensing S rRNA16 مورد شناسایی قرار گرفت که به عنوان Bacillus pumilus شناسایی شد. به علاوه میزان حذف غلظت های مختلف تولوئن در زمان رشد این باکتری مورد بررسی قرار گرفت. نتایج نشان می دهد سویه مورد نظر می تواند توانایی مناسبی در تجزیه تولوئن در محیط زیست و پاک سازی ان داشته باشد. تفاصيل المقالة -
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5 - Screening Method for Mononitrotoluenes in Natural Waters Using Magnetic Solvent Bar Liquid-Phase Micro-extraction Followed by Gas Chromatography-Flame Ionization Detection
Hadi Farahani Behrooz MirzaA simple andefficient hollow fiber-based method,viz magnetic solvent bar liquid-phasemicroextraction (MSB-LPME) combined with gas chromatography-flame ionization detection (GCFID)has been successfully developed for the trace determination of mononitrotoluenes (MNTs) inn أکثرA simple andefficient hollow fiber-based method,viz magnetic solvent bar liquid-phasemicroextraction (MSB-LPME) combined with gas chromatography-flame ionization detection (GCFID)has been successfully developed for the trace determination of mononitrotoluenes (MNTs) innatural water samples. The analytes were extracted from sample solution to the organic solventimmobilized in a fiber. Following the extraction, the analyte-adsorbed magnetic solvent bar can beeasily isolated from the sample solution by a magnet which could significantlyfacilitate theoperation as well asreducing the total pretreatment time. The bar was mainly eluted withacetonitrile, evaporated to dryness while the residue was dissolved in toluene and finally injectedinto GC-FID. At first, a series of parameters influencing microextraction performance weresystematically investigated and optimized. The values of the detection limit were in the range of0.05-0.08 μg L-1 and the RSD% for the analysis of 50.0μg L-1 of the analytes was below than 5.8%(n = 6). An acceptable linearity (0.996 ≥ r2 ≥ 0.995) and a broad linear range (0.2-200 μg L-1) wereachieved. The method was eventually employed for the preconcentration and determination of theMNTs in environmental water samples and acceptable results were reached. تفاصيل المقالة -
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6 - Application of 2-methylpyridinum p-toluenesulfonate ([2-MPy][p-TSA]) as an efficient catalyst for the one-pot synthesis of hexahydroquinolines-3-carboxamides
Matin Asadi Masoud Mokhtary2-Methylpyridinum p-toluenesulfonate ([2-MPy][p-TSA]) as a novel room temperature ionic liquidwas synthesized and evaluated as a recoverable catalyst for the one-pot synthesis ofhexahydroquinoline-3-carboxamide derivatives by four-component reaction of arylaldehydes,dim أکثر2-Methylpyridinum p-toluenesulfonate ([2-MPy][p-TSA]) as a novel room temperature ionic liquidwas synthesized and evaluated as a recoverable catalyst for the one-pot synthesis ofhexahydroquinoline-3-carboxamide derivatives by four-component reaction of arylaldehydes,dimedone, acetoacetanilide and ammonium acetate in high to excellent yield in ethanol at 50 oC.The [2-MPy][p-TSA] catalyst was characterized via FT-IR, 1H NMR and 13C NMR spectroscopy.An environmentally benign procedure, four-component in one pot reaction, high yields and simplepreparation of the catalyst are some advantages of this work. تفاصيل المقالة -
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7 - One-pot Three-Component Synthesis of Dihydroquinoxalin-2-amines Containing a Ferrocene unit with the Potential of Biological and Pharmacological Activities
Neda Aghaei Nahid ShajariA three-component reaction between 1,2-phenylenediamine, ferrocenecarbaldehyde, and isocyanides in the presence of a catalytic amount of p-toluenesulfonic acid for the synthesis of 3,4-dihydroquinoxalin-2-amine derivatives containing a ferrocene unit is reported. This a أکثرA three-component reaction between 1,2-phenylenediamine, ferrocenecarbaldehyde, and isocyanides in the presence of a catalytic amount of p-toluenesulfonic acid for the synthesis of 3,4-dihydroquinoxalin-2-amine derivatives containing a ferrocene unit is reported. This approach is an effective procedure because the products have a broad spectrum of biological and pharmacological activities such as insecticide, fungicide, herbicide, anthelmintic, antibacterial, antimycobacterial, antiprotozoal, anticancer and antibiotic properties. تفاصيل المقالة -
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8 - Employing α-Fe2O3 /Mn2P2O7 as a nano photocatalyst for degradation of toluene in aqueous environment
Sajjad Mafi Kazem MahanpoorThe existence of different resistant organic pollutants especially toxic organic aromatics such as Toluene in aquatic environments has become a significant environmental matter in recent years. In this paper, α-Fe2O3 Nano-spheres are immobilized on the surface of Mangan أکثرThe existence of different resistant organic pollutants especially toxic organic aromatics such as Toluene in aquatic environments has become a significant environmental matter in recent years. In this paper, α-Fe2O3 Nano-spheres are immobilized on the surface of Manganese Pyrophosphate (Mn2P2O7) support using Forced Hydrolysis and Reflux Condensation (FHRC) method. Products were characterized by FTIR, SEM, BET EDX, and XRD. The photocatalytic activity of α-Fe2O3/Mn2P2O7 was investigated for the removal of Toluene in aqueous solution by UV/H2O2 system. The chemical oxygen demand (COD) measurements were used to determine the amount of Toluene removal. The experiments were designed based on four affecting variables including pH, catalyst content, initial Toluene concentration and H2O2 at three levels using Box-Behnken experimental design. The results of this study showed that α-Fe2O3/Mn2P2O7 as a new photo catalyst has a higher photocatalytic activity than α-Fe2O3 nanoparticles. Based on the achieved results, the maximum degradation efficiency was 97.14% in optimal conditions. تفاصيل المقالة -
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9 - Employing α-Fe2O3 /Mn2P2O7 as a nano photocatalyst for degradation of toluene in aqueous environment
Sajjad Mafi Kazem MahanpoorIn this study, α-Fe2O3 nano-spheres are immobilized on the surface of manganese pyrophosphate(Mn2P2O7) support using forced hydrolysis and reflux condensation (FHRC) method. The synthesizedα-Fe2O3/Mn2P2O7 were characterized by FTIR, SEM, BET EDX, and XRD. Th أکثرIn this study, α-Fe2O3 nano-spheres are immobilized on the surface of manganese pyrophosphate(Mn2P2O7) support using forced hydrolysis and reflux condensation (FHRC) method. The synthesizedα-Fe2O3/Mn2P2O7 were characterized by FTIR, SEM, BET EDX, and XRD. The photocatalytic activity fromα-Fe2O3/Mn2P2O7 was investigated for the removal of toluene in aqueous solution by UV/H2O2 system. Thechemical oxygen demand (COD) measurements were used to determine the amount of toluene removal.The experiments were designed based on four affecting variables, including pH, catalyst content, initialtoluene concentration and H2O2 at three levels using Box-Behnken experimental design. The results ofthis study showed that α-Fe2O3/Mn2P2O7 as a new photocatalyst has a higher photocatalytic activity thanα-Fe2O3 nanoparticles. Based on the achieved results, the maximum degradation efficiency was 97.14%in optimal conditions. تفاصيل المقالة -
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10 - Catalytic oxidation of airborne toluene by using copper oxide supported on a modified natural diatomite
Seyed Reza Azimi Pirsaraei Hasan Asilian Mahabadi Ahmad Jonidi JafariThe catalytic oxidation of toluene over copper oxide supported on natural diatomite was investigated. The catalyst was prepared by the wet impregnation method and characterized by using the Brunauer Emmett Teller (BET), field emission Scanning Electron Microscopy (FESEM أکثرThe catalytic oxidation of toluene over copper oxide supported on natural diatomite was investigated. The catalyst was prepared by the wet impregnation method and characterized by using the Brunauer Emmett Teller (BET), field emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and Temperature-programmed reduction (TPR) analysis. The highest catalytic performance for airborne toluene oxidation was obtained at 14 wt% Cu loading. The toluene conversion at 270°C and 380°C, were 50% and 90%, respectively. According to the results of GC/MS and formation the CO2 in effluent gas, no intermediates such as CO or other hydrocarbons were detected and the selectivity towards CO2 was almost 100%. تفاصيل المقالة -
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11 - Layered double hydroxides: Novel nanocatalysts for combustion of gaseous toluene from polluted air
Sepideh Naghel-Danaei Seyed Ali Hosseini Aligholi NiaeiThe catalytic performance of Ni-Al, Mg-Al, and Co-Ni LDHs as novel nanocatalysts was evaluated in the oxidation of toluene. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). أکثرThe catalytic performance of Ni-Al, Mg-Al, and Co-Ni LDHs as novel nanocatalysts was evaluated in the oxidation of toluene. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The XRD and FTIR approved the structure and functional groups of the LDH, respectively. Also, the presence of cations with different oxidation state confirmed by XRD. According to this result, Mars Van Krevelen (MVK) mechanism was suggested for the combustion of toluene over the LDH nanocatalysts. The SEM results indicated that the nanostructure and layered morphology of the catalysts. All LDHs exhibited catalytic activity for toluene oxidation. T80 (temperature for 80% conversion for toluene) for Co-Ni, Ni-Al and Mg-Al LDH catalysts were 225, 277 and 350 °C, respectively. So, the Co-Ni LDH showed the highest activity. Furthermore, Ni-Al LDH exhibited the highest thermal stability. So, we concluded that Ni-Al LDH is a superior catalyst for toluene oxidation in the studied series. تفاصيل المقالة -
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12 - جداسازی و شناسایی باکتری های تجزیه کننده تولوئن از مناطق آلوده به نفت رودخانه قره سو در کرمانشاه
نرگس شمسی رویا مروجسابقه و هدف: اصلاح زیستی یکی از روش های پاکسازی آلودگی های نفتی است که به دلیل مزایایی مانند هزینه اندک، کارایی بالا و سازگاری با محیط زیست، در سال های اخیر بسیار مورد توجه بوده است. رودخانه قره سو نیز یکی از مناطقی است که به دلیل مجاورت با پالایشگاه نفت کرمانشاه، در سا أکثرسابقه و هدف: اصلاح زیستی یکی از روش های پاکسازی آلودگی های نفتی است که به دلیل مزایایی مانند هزینه اندک، کارایی بالا و سازگاری با محیط زیست، در سال های اخیر بسیار مورد توجه بوده است. رودخانه قره سو نیز یکی از مناطقی است که به دلیل مجاورت با پالایشگاه نفت کرمانشاه، در سال های اخیر دچار آلودگی نفتی شده است. این مطالعه با هدف جداسازی و شناسایی باکتری های تجزیه کننده تولوئن از مناطق آلوده به نفت رودخانه قره سو در کرمانشاه انجام شد. مواد و روش ها: این مطالعه به صورت تجربی بر روی نمونه های آب، خاک و لجن فعال مناطق آلوده انجام شد. دو جدایه تجزیه کننده تولوئن با استفاده از غنی سازی بر روی محیط کشت انتخابی حاوی تولوئن به دست آمدند. این جدایه ها با روش های ریخت شناسی کلنی، رنگ آمیزی گرم، آزمون های بیوشیمیایی و توالی یابی ژن 16S rRNA شناسایی شدند. همچنین میزان حذف تولوئن توسط جدایه ها با روش کروماتوگرافی گازی ارزیابی گردید. یافته ها: هر دو جدایه متعلق به گونه باکتریایی سودوموناس پوتیدا بودند. با استفاده از روش کروماتوگرافی گازی ثابت شد که جدایه ها توانستند تولوئن موجود در محیط کشت (با غلظت v/v 0.5 درصد) را در مدت 72 ساعت به ترتیب به میزان 89% و 87% تجزیه نمایند. همچنین این جدایه ها قادر بودند شرایط نامساعد دمایی، pH و اسمولاریته را تحمل نمایند. همچنین اثبات گردید که این جدایه ها قادرند در حضور دیگر آلاینده های نفتی (بنزن، اتیل بنزن، زایلن) نیز به طور کارآمد به فعالیت و رشد خود ادامه دهند. نتیجه گیری: نتایج نشان داد که این جدایه ها به دلیل توانایی رشد در غلظت بالای تولوئن و تجزیه طیف وسیعی از آلاینده ها می توانند کارآیی بالایی برای حذف آلاینده های نفتی از محیط زیست داشته باشند. تفاصيل المقالة -
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13 - Potassium carbonate as a base for cycloalkylation of diethyl malonate and ethyl cyanoacetate in solid-liquid two phase systems
Fuping Liu Yan Zhu Ming LuThe cycloalkylation of diethyl malonate and ethyl cyanoacetate with alkyl dihalide was investigated by using comminuted potassium carbonate as a base and toluene as a solvent in the presence of hexadecyltrimethylammonium bromide (HTMAB) as a phase-transfer catalyst, whi أکثرThe cycloalkylation of diethyl malonate and ethyl cyanoacetate with alkyl dihalide was investigated by using comminuted potassium carbonate as a base and toluene as a solvent in the presence of hexadecyltrimethylammonium bromide (HTMAB) as a phase-transfer catalyst, which provided a conventional procedure with the advantage of short reaction period and high product yield. The factors influencing the product yield and the reaction mechanism were discussed on the basis of the experimental data. تفاصيل المقالة -
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14 - p-Toluenesulfonic acid a useful and selective reagent for the oxidation of benzoins to benziles under solvent-free condition
Nader Noroozi Pesyan Abdul Hossein Abdul Hossein DabbaghOxidation of some benzoins to benziles is reported by using p-toluenesulfonic acid as aselective oxidation catalyst under solvent-free condition in high yield. The adjacent carbonylgroup is necessary for the oxidation of hydroxyl group in these compounds. The reaction i أکثرOxidation of some benzoins to benziles is reported by using p-toluenesulfonic acid as aselective oxidation catalyst under solvent-free condition in high yield. The adjacent carbonylgroup is necessary for the oxidation of hydroxyl group in these compounds. The reaction iscarried out in a sand-bath at 100 °C with minimum by-products. تفاصيل المقالة -
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15 - Structure-radical scavenging activity relationships of hydroxytoluene derivatives
Adnan Bekhit Baye Akele Ariaya HymeteResearch works proposed that radical scavenging activity of flavonoids is due to ring B, andthe remaining part of the molecule can be disregarded. Thus the objective of this work is toobserve whether hydroxytoluenes account the radical scavenging activity of flavonoid a أکثرResearch works proposed that radical scavenging activity of flavonoids is due to ring B, andthe remaining part of the molecule can be disregarded. Thus the objective of this work is toobserve whether hydroxytoluenes account the radical scavenging activity of flavonoid and toestablish structural requirements for their activity (as they showed appreciable activity) andelucidate a comprehensive mechanism that can explain their activity and termination. Thus, theradical-scavenging activity of nine hydroxytoluene derivatives against 2,2-diphenyl-1-picrylhydrazyl, DPPH was determined. The relative change in energy (ΔHf) associated with theformation of phenolic radicals and the spin distributions in these radicals were determined usingcomputational programs (Density function theory and Hartree Fock). By correlatingexperimental data with ΔHf, the most active compounds and structural features that areresponsible for their activities were identified. Reaction product of 4-methyl catechol with 2,2-diphenyl-1-picrylhydrazyl, DPPH was isolated and characterized in order to unravel themechanism of termination of most active hydroxytoluenes. Termination enthalpy (ΔH2) ofmethyl-catechols and methyl-hydroquinone, once the termination mechanism explained, wascalculated to understand its role in the radical scavenging activity. تفاصيل المقالة -
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16 - Evaluation of Air Pollutants Caused by Benzene, Toluene, and Xylene at Kazakhstan Petrochemical Industries Inc. LLP in 2022
Kuanysh Syman Zuhra Muter Saleh Ahmed Hasoon Farah A. Dawood Zinah Salem Awfi Luau Ali Khaleel Bekenova Nazym Omarov Nazarbek Bakytbekovich Aldiyar E. MasalovVolatile organic compounds (VOCs) such as benzene, toluene, and xylene are toxic air pollutants which are released into the atmosphere by various human activities such as gasoline production and use, chemical manufacturing and incineration of certain waste. These pollut أکثرVolatile organic compounds (VOCs) such as benzene, toluene, and xylene are toxic air pollutants which are released into the atmosphere by various human activities such as gasoline production and use, chemical manufacturing and incineration of certain waste. These pollutants are also harmful to the environment, causing harm to plants, aquatic life, and soil quality. Therefore, it is important to implement measures to reduce emissions from these substances. The purpose of this paper is to evaluate the air pollutants caused by benzene, toluene, and xylene at Kazakhstan Petrochemical Industries Inc. LLP in 2021–2022. In order to calculate the sample size for this cross-sectional study, the preliminary evaluation findings from a related study that measured the concentration of hydrocarbons in petrochemical facilities were employed. 281 samples were gathered between the winter and summer of 2022. The national institute for occupational safety and health (NIOSH) methods of 1501 was applied to conduct the sampling and analysis of pollutants. The air was sampled using a charcoal tube sampler that was attached to a pump. The chemicals were then extracted using the solvent carbon disulfide (CS2), and samples were then analyzed using a capillary-equipped gas chromatography-mass spectrometer. The collected data were analyzed by SPSS software version 23.0. The findings demonstrated that benzene concentrations in the sampling areas throughout the winter and summer were higher than the recommended value advised by the American conference of governmental industrial hygienists (ACGIH). تفاصيل المقالة
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