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Assessment of Non-Ionizing Radiation Emissions from Cell Phone Towers
2023
Alkhalidi, Murtadha | Al-Shakban, Mundher | Kalifa, Ahmed | A. Abdul Ridha, Hamzah
People’s growing anxiety, and fear of the issue of a large number of mobile phone towers, as well as the lack of studies dealing with this issue at the level of the country in general, and the governorate in particular. All these reasons led to the issue of non-ionizing rays given off by mobile telephone masts on the table of worries about how this radioactivity will affect people's health. Non-ionized radiation emissions were measured by taking 280 readings for the three frequency packets 900, 1800, and 1840 MHz, which are sequential-Global System Mobile (GSM), of 20 cell phone towers in the Al-Amara, the city center of Misan prefecture. Four readings were collected for each frequency, with the highest value for overlap between electromagnetic field and frequency being chosen. A selective Radiation Meter (SRM-3006) was the device used in this study. It was found that the amount of non-ionizing radiation emitted by the towers taken in the study, and for the frequencies (900, 1800, and 1840 MHz) was, in a successive manner (309 × 10-8, 7 ×10-8, and 1109×10-7 MHz). Thus, the measured values of radiation were less than the surveyed limit (4×10-1 μW/cm2) provided for by the law of Iraq’s Determinants for Non-ionized Radiation Emissions (IDNREs).
显示更多 [+] 显示较少 [-]Analytical Methods for Extraction, Determination and Degradation of Diazinon in Soil Samples
2023
Dehghan Abkenar, Shiva | khakipour, Nazanin | Ganjali, Mohammad Reza
Diazinon is an organophosphorus insecticide that was widely used in agriculture to control pests on crops. It acts as an acetylcholinesterase inhibitor, which means that it interferes with the normal functioning of the nervous system of insects, leading to their death. Diazinon can also have an impact on human health and the environment, as it can contaminate water and soil and pose a risk to non-target species, including humans and animals. This review paper shows the progress made in the last years in analytical methods applied for the purpose of extraction, detection and degradation of Diazinon as an important environmental pollutant. A variety of sampling and analytical methods have been developed to measure diazinon and its metabolites in different media. The most popular methods for the identification and analysis of Diazinon are liquid and gas chromatography, liquid-liquid extraction, and solid-phase extraction (SPE). The focus of this review is on the identification, measurement, and elimination of diazinon as a major soil pollutant. It begins with a discussion of analytical techniques, followed by an examination of methods for removing diazinon from soil.
显示更多 [+] 显示较少 [-]Effect of Auto Road on Spatial Metal Distribution in Dust and Snow Cover
2023
Ankomah Baah, Gabriel | Savin, Igor | Rogova, Olga
The present investigation examined the impact of highways on the global dispersion patterns of metallic elements present in dust and snow. A total of 18 mixed snow samples were collected from both sides of the Moscow-Tambo-Astrakhan Caspian Highway by the end of the winter season. The analysis of the samples indicated the presence of 35 distinct chemical elements, where Al, Ba, Ca, Fe, K, Mg, Na, and Zn were identified as the primary contaminants. The primary area of pollution on the windward side originating from the road spans a distance of 20-40 meters, while on the leeward side, it extends to 10 meters. The data presented suggests that the metals found in highways exhibited variability in terms of their solubility in water and concentration. Our findings demonstrate that the predominant wind directions affect the dispersion of pollutants. Furthermore, it was observed that the region with a higher concentration of metal on the side of the road facing the wind had a thickness that was 2-3 times less than that of the opposite side. It is advisable to conduct a subsequent inquiry within the ensuing five years to obtain dependable data regarding the extent of metal pollution.
显示更多 [+] 显示较少 [-]Forecasting and Seasonal Investigation of PM10 Concentration Trend: a Time Series and Trend Analysis Study in Tehran
2023
Pardakhti, Alireza | Baheeraei, Hosein | Dehhaghi, Sam
In this study, a multitude of statistical tools were used to examine PM10 concentration trends and their seasonal behavior from 2015 to 2021 in Tehran. The results of the integrated analysis have led to a better understanding of current PM10 trends which may be useful for future management policies. The Kruskal – Wallis test indicated the significant impact of atmospheric phenomena on the seasonal fluctuations of PM10. The seasonal decomposition of PM10 time series was conducted for better analysis of trends and seasonal oscillations. The seasonal Mann-Kendall test illustrated the significant possibility of a monotonic seasonal trend of PM10 (p = 0.026) while showing its negative slope simultaneously (Sen = -1.496). The forecasting procedure of PM10 until 2024 comprised 15 time series models which were validated by means of 8 statistical criteria. The model validation results indicated that ARIMA (0,1,2) was the most satisfactory case for predicting the future trend of PM10. This model estimated the concentration of PM10 to reach approximately 79.04 (µg/m3) by the end of 2023 with a 95% confidence interval of 51.38 – 107.42 (µg/m3). Overall, it was concluded that the use of the aforementioned analytical tools may help decision-makers gain a better insight into future forecasts of ambient airborne particulate matter.
显示更多 [+] 显示较少 [-]An Investigation on Advances in Metal Extraction from Electronic Wastes by Supercritical Water and Carbon Dioxide
2023
Fallah Haghighi, Hamed | Khorshidi, Jamshid | Zarei, Taleb | Bakhshan, Younes
Today, the application of supercritical fluid extraction (SFE) has been the focus of many researchers in various industries due to suitable operating conditions, environmental friendliness (no use of organic solvents) and high efficiency. In this process, a solvent is used for separation in supercritical conditions. Pharmaceutical, oil extraction, and oil and gas industries have conducted extensive research in this field. Electronic and electric devices are constantly being upgraded and updated due to the rapid advancement of science and technology, which creates a number of issues with handling electric and electronic waste (e-waste). The most significant issue is that it is challenging to safely dispose of halogen flame retardants and refractory polymers in e-waste. Supercritical fluid (SCF) techniques provide significant environmental benefits over previous disposal methods like pyrolysis and acid leaching since they pose no dangers for air or water contamination. This study discusses and provides a summary of the basic concepts and appropriate factors of supercritical fluid extraction (SFE). SCF methods were claimed to have recovered precious metals, base metals, and other inorganic minerals from e-waste with a recovery efficiency of further 93%. This study reviews the recent advances in supercritical water (SCW) and supercritical carbon dioxide (SCCO2) extraction technologies for metal recovery from e-wastes. On the other hand, hybrid technologies are significantly improving in this field which could be considered for future studies.
显示更多 [+] 显示较少 [-]Prioritizing Local Biomass Resources for Biofuel Production by a Fuzzy Hybrid Decision Making Approach (The Case of Hormozgan Province in Iran)
2023
nohegar, Ahmad | Alavi Naeini, Mina | Alavi naeini, Ali
In recent years, increasing in energy demand and the importance of using energy with minimum green- house gas emission (GHG) leads researchers to study about renewable energy resources such as biomasses. Biomasses can be converted to biofuels by applying the appropriate technologies. In this study, a hybrid group fuzzy multi-criteria decision making (MCDM) approach based on step-wise weight assessment ratio analysis (SWARA), technique for order preference by similarity to ideal Solution (TOPSIS), additive ratio assessment (ARAS), weighted aggregated sum product assessment (WASPAS) and simple additive weighting (SAW) in the fuzzy environment is applied to rank biomasses in the case of Hormozgan province in Iran, because of being a coastal area and the access to different types of first, second and third generation resources of biofuel. After ranking these resources by mentioned methods, two aggregated multi-criteria decision making (MCDM) methods (mean rank method and Copeland method) are employed to prioritize these biomasses. Results of mean rank show that municipal solid wastes (MSW), fish wastes and microalgae have the minimum average rank, respectively and the results of Copeland method show that MSW, fish wastes and microalgae have the maximum (wins-loses), respectively. So, these biomasses are the most suitable ones in biofuel production in this province.
显示更多 [+] 显示较少 [-]Urban Rivers Landscape Services Assessment Based on Public Perception in Mehranrood River, Tabriz, Iran
2023
Darabi, Hassan | Rasouli Dehkharghani, Parisa | Ehsani, Amir Houshang | Kordani, Hadis
As natural corridors, urban rivers are often under ecological pressures disturbing their environmental functions, and services over time and space. The landscape services (LS) has been accordingly introduced as an alternative method to evaluate such functions at the landscape scale. In this regard, public perceptions can seriously shape landscape changes, with potentially consistent or inconsistent implications for ecosystem sustainability over time and space. To shed light on this issue, the present study aimed to evaluate the LS of the Mehranrood River running through the city of Tabriz, Iran, from local users' perspective. For this purpose, approximately 365 questionnaires (with the Cronbach's alpha coefficient equal to 0.97) were developed based on the LS indicators and completed by the stakeholders. To analyze the results, structural equation modeling was applied. Afterward, the accuracy of the given model was checked by applying the root-mean-square error of approximation (RMSEA). The results showed that the service provision accounted for the largest number of factors. The cultural services were completely dependent on the presence of production/supply and regulation/maintenance services. The study results demonstrated that, the river had no efficient structures and functions from the stakeholders' perspective. They even believed that the ecological restoration of the Mehranrood River could deliver the potential ability to enhance its LS. Moreover, the respondents were willing to be in close contact with the river if it could be ecologically rehabilitated. Generally, ecological restoration could help boost urban resilience over time through the regeneration of ecological infrastructure, which required a transition from mechanical to ecological thought.
显示更多 [+] 显示较少 [-]Assessment of some Heavy Metals and Health Risks in Water and Shrimps from a Polluted Mangrove Swamp, Niger Delta, Nigeria
2023
Davies, Davies, Ibienebo Chris | Anyanwu, Emeka
The heavy metal concentrations of water and shrimp (Penaeus monodon) from Isaka Bundu swamp, Niger Delta were evaluated between January and June 2022. The non-carcinogenic health risk assessment was used to assess the water's suitability for recreation and the shrimps for consumption. Five heavy metals (Pb, Cu, Cd, Ni, and Zn) were assessed in both media using standard methods and compared with national and international standards. The Chronic daily intake (CDI) for Cd and Cu (in children) exceeded their respective reference doses while hazard quotients (HQs) for Cd and Cu (in children) and all the hazard indices were greater than 1 in the water. All the target hazard quotients (THQs) and total hazard index (THIs) were lower than 1 in the shrimps. The heavy metal concentrations, CDIs, HQ/THQs and HI/THIs were higher in the more impacted stations 1 and 3. Based on the heavy metal concentrations and health risk assessment, the waters of the Isaka Bundu swamp are unsafe for recreational purposes. However, shrimps are safe for human consumption. The high concentrations of heavy metals in the water influenced the concentrations in the shrimps. Anthropogenic activities in the area contributed to the heavy metal concentrations in the environment. The results also showed that the children were more prone to adverse health impacts.
显示更多 [+] 显示较少 [-]Feasibility of Production of PET/ZIF-8 Polymer Media to Remove Particles from the Air Stream Compared to HEPA Filter
2023
Kazemi, Meghdad | Kalantary, Saba | Abbasi, Ali Reza | Rahimi Foroushani, Abbas | Golbabaei, Farideh
Polyethylene terephthalate (PET) and Zeolitic Imidazolate Framework-8 (ZIF-8) were used to investigate the feasibility of producing electrospun PET/ZIF-8 polymer media in removing particles from the air stream to compare with the HEPA filter. To make PET/ZIF-8 media, concentrations of 0.5, 1, 2.5, and 5 wt.% of ZIF-8 were dissolved in PET20% solutions, and dispersed for 10 min. Then, PET/ZIF-8 media was produced with an ESDP30 model electrospinning device. The efficiency and pressure drop of nanofiber media were measured with a respiratory mask and filter test device. The FTIR, XRD and SEM analysis were carried out to obtain the characteristics of nanofibers. The overall XRD pattern and its peaks were in reasonable agreement with previous findings that confirmed the structure of ZIF-8. The FTIR spectra of the obtained materials confirm that the chemical bond structure corresponds to that reported for ZIF-8. In total, The PET/ZIF-8(1%) media efficiency, pressure drop, the average diameter of nanofibers, and the quality factor were 100%, 320 Pa, 171.18±37.91 nm and 0.0143 Pa-1, respectively, which was better than other electrospun PET/ZIF-8 media and HEPA filters. According to the results, with an increase in the weight percentage of Zif-8 (>5 wt.%) in the structure of PET/Zif-8 media, due to the increase in the viscosity of the solution jet, the diameter of the produced nanofibers increased and the efficiency of the electrospinning medium decreased.
显示更多 [+] 显示较少 [-]Detection of Microplastics in Drinking Water Treatment Plants in Baghdad City/Iraq
2023
H. Sultan, Hassan | Abdul Wahab Shaker Al-Aadhami, Mohammad | Nihad Baqer, Noor
Microplastics are an emerging environmental pollutant detected in different environments, but studies in Iraq are rare, if not nonexistent. Our research aims to detect the presence of microplastics in raw water and drinking water treatment plants in Baghdad. Water samples were collected (1 liter per sample) from four drinking water treatment plants: Al-Fahama station, Al-Fath Al-Mubin station, Al-Dora station, and Al-Madaen station, which receive water from the Tigris River. The microplastic shape was determined by a fluorescent microscope examination after staining with Nile dye. FTIR spectrophotometer used to determine microplastic compounds. The results showed, according to FTIR examination, that the most critical types of microplastic compounds in water samples were Nylon, Polycarbonate, High-density polyethylene, Polystyrene, Polyamide, Polyethylene terephthalate, and Polyurethane, and Microplastics number were (17-62 MPs /L) in raw water, while in drinking water were (9-40 MPs/L). The fibers form is the predominant form of microplastics in natural and drinking for stations: Al-Fahamah (91.6%, 66.6% respectively), Al-Fath Al-Moubin (58.8%, 77.7% respectively ), Al-Doura (65.3%, 52.5% respectively), Drinking water in Al-Madaen station (40.0%). At the same time, the spherical shape is predominant in the raw water of Al-Madaen station (82.2%).In conclusion, the current study indicated the pollution of drinking water treatment plants with microplastics.
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