Influence of Air Pollution on Chemical Quality of Wet Atmospheric Deposition: a Case Study in Urmia, Iran

Increased combustion of fossil fuel owing to the energy requirement is a main cause of air pollution throughout the world. Atmospheric precipitation is considered as a major water resource for indoor, municipal, industrial and agricultural uses. This study was aimed to evaluate the effect of air pollution on chemical quality of rain and snow in Urmia, a city in northwest of Iran. Sampling was performed during the wet seasons from October to March at six sampling stations in different locations of the city. Acidity, alkalinity, NO3- , SO42-, Cl- and pH contents of the collected samples were analyzed. All samples showed a pH value of more than 6.8, and lower acidity than alkalinity, therefore, the precipitations were not acidic. Maximum concentrations of SO42- and NO3- in the samples were 5 and 8.8mg/L, respectively. Chloride was varied from 1 to 11.5 mg/L with the highest measures observing in autumn. According to the results, concentrations of the analyzed parameters in wet precipitations in Urmia were within the natural ranges except chloride ions, which was higher than its common level in the atmosphere. This phenomenon may be the result of desert dusts which transfers by wind from the west border to Iran.

Compression creep measurements in pultruded angle sections made of fibre glass reinforced plastic

A study aimed at investigating the performance of pultruded fibre glass reinforced plastic (FGRP) materials subjected to both the time-independent and the time-dependent response of angle stubs and coupons was conducted. Angle stubs and coupons were made of isophtalic polyester resin reinforced with an E-glass fibre glass mat of 35%-45% of the weight. The stub dimensions were of 50.8 mm $times$ 50.8 mm $times$ 6.35 mm and their length was 305 mm. The compression coupons were cut in a prismatic shape according to ASTM Standard D695-89 with 12.70 mm $times$ 6.35 mm cross-section and a length of 31.75 mm.In the time-independent short-term study, the FGRP angle stubs and coupons were subjected to axial compression loading with two different testing configurations.In the time-dependent long-term study, three angle stubs were first subjected to a 350 hour preliminary creep test, followed by 150 hours of creep recovery, with three lengths and configurations of strain gauges. Finally, a last series of tests was carried out on three angle stubs instrumented with 12 5-mm long gauges. Coupon creep tests were carried out in parallel with the stub tests. The total duration of the tests was 2500 hours in creep and 250 hours in creep recovery. Results indicate a scatter in the order of 15% in creep strain measurements after 2500 hours, for both stub and coupon tests. Predictions using Findley's power law with creep parameters determined from the stub tests and coupon tests are in excellent agreement, both with one another and with actual creep strain measurements on the stubs. The Boltzman superposition principle was used to compare the experimental creep recovery results with predictions from Findley's model, and excellent agreement was also observed. (Abstract shortened by UMI.

New Elaborated Technique for Isolation and Purification of Limonene from Orange Oil: Isolation of limonene from orange oil

Essential oil of the orange peel which was extracted by hydrodistillation method showed 50 different mono- and sesquiterpenes on GC-MS analysis, in whichlimonene had the highest percentage (92.4%). Due to various important uses of the compound, a method was developed for isolation and purification of limonene. In this method, for extra purification, a fractional distillation on Vigreux column under 100 mm Hg vacuum was used which resulted in 96.7% purity for limonene.Subsequent chromatography by two different packages of silica gel and active charcoal columns resulted in 99.4% and 99.9 % purity of limonene, respectively

Mechanical, Durability, and Gamma Ray Shielding Characteristics of Heavyweight Concrete Containing Serpentine Aggregates and Lead Waste Slag

Heavyweight concrete is used to prevent harmful radiation for the construction of hospital, military, and nuclear power plants and also to increase the durability for the construction of marine concrete structures. In this research, using a combination of serpentine aggregates and lead slag, the mechanical, durability, impact resistance, and shielding properties of heavyweight concrete were examined. The variables included fine and coarse serpentine aggregates, which were replaced with normal fine and coarse aggregates in amounts of 0, 25, 50, and 100 percent, respectively. The lead slag in all samples was considered constant. Slump, compressive strength, flexural strength, water penetration depth, impact resistance (drop hammer), and gamma ray attenuation coefficient tests were conducted. The chemical composition of serpentine aggregates and lead slag were evaluated by X-ray powder diffraction. The results showed that the density and linear attenuation coefficient (LAC) increased with the increase of fine and coarse serpentine aggregates in heavyweight concrete containing lead slag. The highest density and LAC were obtained in a sample in which 100% fine serpentine aggregates and 100% coarse serpentine aggregates were used. Using 25% of serpentine fine aggregates and 25% of serpentine coarse aggregates in heavyweight concrete samples containing lead slag has achieved the highest compressive strength and flexural strength. But with the increase of fine and coarse serpentine aggregates to more than 25%, the upward trend of increasing compressive strength decreased. Silica constitutes a large part of the chemical structure of serpentine aggregates (about 42%). Increasing the amount of serpentine aggregates in concrete mixes leads to excessive release of calcium hydroxide in concrete. This issue can lead to the formation of a weak zone in concrete and decrease the compressive and impact resistance

Progressive collapse analysis methods due to blast loading in steel moment frames

One of the methods for assessing the potential of progressive collapse occurrence is the APM method. This method done by direct removing of one or several columns. However, in this method the damage of adjacent elements of removed columns under blast conditions was ignored and this issue can lead to an incorrect prediction of progressive collapse. Therefore in this study to evaluate the potential of progressive collapse due to blast loading a 4st steel moment frame building with Abaqus/CAE 6.11 software is simulated, and two methods '' alternative load path and applied of blast load directly'' were evaluated in this study. The results indicate that in assessment of the potential of progressive collapse occurrence by considering the blast loading as the initial reason of failure, the structure response will be different compared with the common methods that used for evaluation of progressive collapse occurrence and in those methods the initial reason of progressive collapse was ignored

Mortality and morbidity due to exposure to Ambient NO2, SO2, and O3in Isfahan in 2013–2014

Background: The presence of air pollutants such as CO, NO2, SO2, O3, and PM in the ambient air mainly emitted from fossil fuels combustion has become a major health concern. The aims of this study were to estimate the attribution of NO2, SO2, and O3 in the premature deaths and prevalence of cardiovascular and respiratory diseases in Isfahan in 2013–2014. Methods: In this study, short-term health effects (total mortality, cardiovascular and respiratory mortality, chronic obstructive pulmonary disease, and acute myocardial infarction) of exposure NO2, SO2, and O3 on the population of Isfahan were assessed using AirQ 2.2.3 software suggested by the World Health Organization (WHO). Results: The result showed that from nonaccident total mortality in 2013–2014 in Isfahan, the attributable proportion related to NO2, SO2, and O3 were 1.03% (109 cases), 3.46% (365 cases), and 1.29% (136 cases), respectively. The percentage of days that people were exposed to the highest concentration of NO2 (40–49 μg/m3), SO2 (60–69 μg/m3), and O3 (40–49 μg/m3) was 34.46%, 16.85%, and 42.74% of a year, respectively. Total mortality attributed to NO2, SO2, and O3exposure was 0.36%, 0.79%, and 0.83%, respectively. Conclusions: The concentrations of NO2and SO2were upper than the WHO guidelines. The Air-Q software in spite of its limitations can provide useful information regarding the health outcome of the air pollutants. The results estimated in this study were considerable. This information can help the health authorities and policy makers to draw suitable strategies and fulfill effective emission control programs

Prediction of atmospheric PM2.5 level by machine learning techniques in Isfahan, Iran

Abstract With increasing levels of air pollution, air quality prediction has attracted more attention. Mathematical models are being developed by researchers to achieve precise predictions. Monitoring and prediction of atmospheric PM2.5 levels, as a predominant pollutant, is essential in emission mitigation programs. In this study, meteorological datasets from 9 years in Isfahan city, a large metropolis of Iran, were applied to predict the PM2.5 levels, using four machine learning algorithms including Artificial Neural |Networks (ANNs), K-Nearest-Neighbors (KNN), Support Vector |Machines (SVMs) and ensembles of classification trees Random Forest (RF). The data from 7 air quality monitoring stations located in Isfahan City were taken into consideration. The Confusion Matrix and Cross-Entropy Loss were used to analyze the performance of classification models. Several parameters, including sensitivity, specificity, accuracy, F1 score, precision, and the area under the curve (AUC), are computed to assess model performance. Finally, by introducing the predicted data for 2020 into ArcGIS software and using the IDW (Inverse Distance Weighting) method, interpolation was conducted for the area of Isfahan city and the pollution map was illustrated for each month of the year. The results showed that, based on the accuracy percentage, the ANN model has a better performance (90.1%) in predicting PM2.5 grades compared to the other models for the applied meteorological dataset, followed by RF (86.1%), SVM (84.6%) and KNN (82.2%) models, respectively. Therefore, ANN modelling provides a feasible procedure for the managerial planning of air pollution control

Spatial analysis and attributable mortality to outdoor air pollutants in ‎Isfahan

Introduction and purpose: Long term exposure to air pollutants can result in the development and acceleration of various conditions, such as cardiac and respiratory problems, reduced lung function, chronic bronchitis, asthma, pulmonary cancer, and even death. Regarding this, the aim of the present study was to perform a spatial analysis of air pollution and mortality in Isfahan, Iran. Methods: In this ecological study, the spatial analysis of particulate matter 10 μm (PM10), PM2.5, ozone (O3), sulfur dioxide (SO2), and nitrogen dioxide (NO2) was performed using the geographic information system. Additionally, the evaluation of the premature deaths attributable to these pollutants was carried out through the AirQ software version 2.2. Results: According to the results of the spatial analysis, the eastern part of Isfahan had higher concentration of air pollutants, compared to other directions. There were 481, 493, 117, 102, and 54 mortality cases attributed to PM10, PM2.5, O3, SO2, and NO2, respectively. In addition, PM10 was found to have the highest health effects among other pollutants. Conclusion: As the findings of this study indicated, PM10 had the highest concentration in Isfahan city. With respect to the fact that air pollutants accounted for almost 15.8% of the total mortality rate in this city, there is an argent need to adapt some strategies to reduce the emissions of air pollutants

Maternal exposure to benzophenone derivatives and their impacts on offspring's birth outcomes in a Middle Eastern population

Abstract Widespread use of benzophenones (BPs), a group of environmental phenolic compounds, is suspected of interfering with human health. The association of prenatal exposure to benzophenone derivatives with birth outcomes including birth weight and length, head, arm and thoracic circumference, abnormalities, corpulence index and anterior fontanelle diameter (AFD) was investigated. Mother-infant pairs of 166 within PERSIAN cohort population in Isfahan, Iran, in the 1st and 3rd trimesters of pregnancy were assessed. Four common benzophenone metabolites including 2,4-dihydroxy benzophenone (BP-1), 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-OH-BP) and 2,2′-dihydroxy-4-methoxy benzophenone (BP-8) were measured in maternal urine samples. The median concentration of 4-OH-BP, BP-3, BP-1 and BP-8 were 3.15, 16.98, 9.95 and 1.04 µg/g Cr, respectively. In the 1st trimester, 4-OH-BP showed a significant correlation with AFD in total infants, decreasing 0.034 cm AFD per a log unit increase of 4-OH-BP. Within the male neonates, 4-OH-BP in the 1st and BP-8 in the 3rd trimester were significantly associated with head circumference and AFD increase, respectively. Among female neonates in the 3rd trimester, increasing 4-OH-BP and BP-3 concentration was correlated with a decrease in birth weight and AFD, respectively. This study demonstrated that all the target BP derivatives can influence normal fetal growth at any age of the pregnancy, nevertheless, to support these findings further studies are needed in a large and different group population

Influence of Air Pollution on Chemical Quality of Wet Atmospheric Deposition: a Case Study in Urmia, Iran

Increased combustion of fossil fuel owing to the energy requirement is a main cause of air pollution throughout the world. Atmospheric precipitation is considered as a major water resource for indoor, municipal, industrial and agricultural uses. This study was aimed to evaluate the effect of air pollution on chemical quality of rain and snow in Urmia, a city in northwest of Iran. Sampling was performed during the wet seasons from October to March at six sampling stations in different locations of the city. Acidity, alkalinity, NO3- , SO42-, Cl- and pH contents of the collected samples were analyzed. All samples showed a pH value of more than 6.8, and lower acidity than alkalinity, therefore, the precipitations were not acidic. Maximum concentrations of SO42- and NO3- in the samples were 5 and 8.8mg/L, respectively. Chloride was varied from 1 to 11.5 mg/L with the highest measures observing in autumn. According to the results, concentrations of the analyzed parameters in wet precipitations in Urmia were within the natural ranges except chloride ions, which was higher than its common level in the atmosphere. This phenomenon may be the result of desert dusts which transfers by wind from the west border to Iran.