Browsing by Author "Torkmahalleh, M. A."

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Open Access
Evaluation of NO2 column variations over the atmosphere of Kazakhstan using satellite data
(SPIE, 2018) Darynova, Z.; Maksot, A.; Kulmukanova, L.; Malekipirbazari, M.; Sharifi, H.; Torkmahalleh, M. A.; Holloway, T.
Tropospheric NO2 concentrations obtained from the measurements of the Ozone Monitoring Instrument on board the NASA Aura satellite from 2005 to 2016 were studied to identify major NO2 emission hot spots, trends, and seasonal variations over Kazakhstan. Emission hot spots are observed over the locations of thermal power plants (Ekibastuz) and major urban and industrial regions (Almaty and Shymkent), as well as the capital city (Astana). Some decreasing trends have been observed for NO2 over Ekibastuz, whereas the regions of Almaty and Shymkent showed increasing trends due to industrial growth. The seasonal pattern of the NO2 concentration shows a difference between three industrial cities of Almaty, Shymkent, and Ekibastuz versus the rest of Kazakhstan. In these three cities, a NO2 maximum is found during wintertime, which we attribute to seasonality of emissions associated with electricity production and the longer chemical lifetime of NO2 in winter. In contrast, in Astana and the rest of Kazakhstan, the NO2 concentration reaches a maximum in the summer.
Open Access
Formation of cluster mode particles (1–3 nm) in preschools
(Elsevier BV, 2021-11-23) Torkmahalleh, M. A.; Turganova, K.; Zhigulina, Z.; Madiyarova, T.; Adotey, E. K.; Malekipirbazari, Milad; Buonanno, G.; Stabile, L.
This study is the first study that reports the cluster particle (1–3 nm) formation (CPF) in two modern preschools located in Nur-Sultan city of Kazakhstan from October 28 to November 27, 2019. The average particle number concentration and mode diameter values during major CPF events in Preschool I and Preschool II were found to be 1.90 × 10^6 (SD 6.43 × 106) particles/cm3 and 1.60 (SD 0.85) nm, and 1.11 × 109 (SD 5.46 × 109) particles/cm3 and 2.16 (SD 1.47) nm, respectively. The ultraviolet PM concentration reached as high as 7 μg/m3 in one of the measurement days. The estimated emission rate in Preschool I for CPF events was 9.57 × 109 (SD 1.92 × 109) particles/min. For Preschool II, the emission rate was 7.25 × 109 (SD 12.4 × 109) particles/min. We identified primary cluster particles (CPs) emitted directly from the sources such as candle burning, and secondary CPs formed as a result of the oxidation of indoor VOCs or smoking VOCs. The secondary CPs are likely to be SOA. Indoor VOCs were mainly emitted during cleaning activities as well as during painting and gluing. Indoor VOCs are the controlling factors in the CPF events. Changes in the training and cleaning programs may result in significant reductions in the exposure of the children to CPs.
Open Access
Global air quality and COVID-19 pandemic: do we breathe cleaner air?
(Taiwan Association for Aerosol Research,Taiwan Qijiao Yanjiu Xuehui, 2021-02-08) Torkmahalleh, M. A.; Akhmetvaliyeva, Z.; Omran, A. D.; Omran, F. D.; Kazemitabar, M.; Naseri, M.; Motahareh, N.; Hamed, S.; Malekipirbazari, Milad; Adotey, E. K.; Soudabeh, G.; Neda, E.; Sabanov, S.; Alastuey, A.; Andrade, M. F.; Buonanno, G.; Carbone, S.; Cárdenas-Fuentes, D. E.; Cassee, F. R; Dai, Q.; Henríquez, A.; Hopke, P. K.; Keronen, P.; Khwaja, H. A.; Kim, J.; Kulmala, M.; Kumar, P.; Kushta, J.; Kuula, J.; Massagué, J.; Mitchell, T.; Mooibroek, D.; Morawska, L.; Niemi, J. V.; Ngagine, S. H.; Norman, M.; Oyama, B.; Oyola, P.; Öztürk, F.; Petäjä, T.; Querol, X.; Rashidi, Y.; Reyes, F.; Ross-Jones, M.; Salthammer, T.; Savvides, C.; Stabile, L.; Sjöberg, K.; Söderlund, K.; Raman, R. S.; Timonen, H.; Umezawa, M.; Viana, M.; Xie, S.
The global spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has challenged most countries worldwide. It was quickly recognized that reduced activities (lockdowns) during the Coronavirus Disease of 2019 (COVID-19) pandemic produced major changes in air quality. Our objective was to assess the impacts of COVID-19 lockdowns on groundlevel PM2.5, NO2, and O3 concentrations on a global scale. We obtained data from 34 countries, 141 cities, and 458 air monitoring stations on 5 continents (few data from Africa). On a global average basis, a 34.0% reduction in NO2 concentration and a 15.0% reduction in PM2.5 were estimated during the strict lockdown period (until April 30, 2020). Global average O3 concentration increased by 86.0% during this same period. Individual country and continent-wise comparisons have been made between lockdown and business-as-usual periods. Universally, NO2 was the pollutant most affected by the COVID-19 pandemic. These effects were likely because its emissions were from sources that were typically restricted (i.e., surface traffic and non-essential industries) by the lockdowns and its short lifetime in the atmosphere. Our results indicate that lockdown measures and resulting reduced emissions reduced exposure to most harmful pollutants and could provide global-scale health benefits. However, the increased O3 may have substantially reduced those benefits and more detailed health assessments are required to accurately quantify the health gains. At the same, these restrictions were obtained at substantial economic costs and with other health issues (depression, suicide, spousal abuse, drug overdoses, etc.). Thus, any similar reductions in air pollution would need to be obtained without these extensive economic and other consequences produced by the imposed activity reductions.
Open Access
The impact on heart rate and blood pressure following exposure to ultrafine particles from cooking using an electric stove
(Elsevier, 2020-08-02) Gabdrashova, R.; Nurzhan, S.; Naseri, M.; Bekezhankyzy, Z.; Gimnkhan, A.; Malekipirbazari, Milad; Tabesh, M.; Khanbabaie, R.; Crape, B.; Buonanno, G.; Hopke, P. K.; Torkmahalleh, A. A.; Torkmahalleh, M. A.; Aleya, L.
Cooking is a major source of indoor particulate matter (PM), especially ultrafine particles (UFPs). Long-term exposure to fine and ultrafine particles (UFPs) has been associated with adverse human health effects. Toxicological studies have demonstrated that exposure to PM2.5 (particles with aerodynamic diameter smaller than 2.5 μm) may result in increased blood pressure (BP). Some clinical studies have shown that acute exposure to PM2.5 causes changes in systolic (SBP) and diastolic blood pressure (DBP), depending on the source of particles. Studies assessing the effect of exposure to cooking PM on BP and heart rate (HR) using electric or gas stoves are not well represented in the literature. The aim of this investigation was to perform controlled studies to quantify the exposure of 50 healthy volunteer participants to fine and ultrafine particles emitted from a low-emissions recipe for frying ground beef on an electric stove. The BP and heart rate (HR) of the volunteers were monitored during exposure and after the exposure (2 h post-exposure). Maximum UFP and PM2.5 concentrations were 6.5 × 104 particles/cm3 and 0.017 mg/m3, respectively. Exposure to UFPs from frying was associated with statistically significant increases in the SBP. The lack of food and drink during the 2 h post-cooking period was also associated with a statistically significant reduction in SBP. No statistically significant changes in DBP were observed. Physiological factors, including heat stress over the stove, movements and anxiety, could be responsible for an elevation in HR at the early stages of the experiments with a subsequent drop in HR after 90 min post-cooking, when study participants were relaxed in a living room.
Open Access
In Press, Corrected Proof: Formation of cluster mode particles (1–3 nm) in preschools
(Elsevier, 2021-11-23) Torkmahalleh, M. A.; Turganova, K.; Zhigulina, Z.; Madiyarova, T.; Adotey, E. K.; Malekipirbazari, Milad; Milad, G.; Stabile, L.
This study is the first study that reports the cluster particle (1–3 nm) formation (CPF) in two modern preschools located in Nur-Sultan city of Kazakhstan from October 28 to November 27, 2019. The average particle number concentration and mode diameter values during major CPF events in Preschool I and Preschool II were found to be 1.90 × 106 (SD 6.43 × 106) particles/cm3 and 1.60 (SD 0.85) nm, and 1.11 × 109 (SD 5.46 × 109) particles/cm3 and 2.16 (SD 1.47) nm, respectively. The ultraviolet PM concentration reached as high as 7 μg/m3 in one of the measurement days. The estimated emission rate in Preschool I for CPF events was 9.57 × 109 (SD 1.92 × 109) particles/min. For Preschool II, the emission rate was 7.25 × 109 (SD 12.4 × 109) particles/min. We identified primary cluster particles (CPs) emitted directly from the sources such as candle burning, and secondary CPs formed as a result of the oxidation of indoor VOCs or smoking VOCs. The secondary CPs are likely to be SOA. Indoor VOCs were mainly emitted during cleaning activities as well as during painting and gluing. Indoor VOCs are the controlling factors in the CPF events. Changes in the training and cleaning programs may result in significant reductions in the exposure of the children to CPs.
Open Access
Key factors impacting performance of a salinity gradient solar pond exposed to Mediterranean climate
(Elsevier Ltd, 2017) Torkmahalleh, M. A.; Askari, M.; Gorjinezhad, S.; Eroğlu, D.; Obaidullah, M.; Habib, A. R.; Godelek, S.; Kadyrov, S.; Kahraman, O.; Pakzad, N. Z.; Ahmadi, G.
Solar ponds are low cost pools of brine solutions with integrated storage zones that harvest incident solar energy and store it as thermal energy. The current study examined the performance of a salinity gradient solar pond under the Mediterranean climatic condition for ten consecutive months of operation, from October 8, 2014 to July 31, 2015. The presented results are based on the experimental data of a small-scale circular pond, 61ï¿½cm in diameter a height of 55ï¿½cm, constructed and operated at Middle East Technical University, Northern Cyprus Campus (METUNCC). The study showed the necessity of regular surface washing and having excess undissolved salt at the lower convective zone (LCZ) to maintain the pond stability. The variations in the temperature of the non-convective (NCZ) and lower convective zones (LCZ) are found to be a function of both ambient temperature and solar irradiation (insolation). The variation of the overall pond's temperature strongly follows the changes in ambient temperature while solar insolation directly affects the increase in temperature gradient by depth. During the period of this study, the pond reached the highest average temperature of 48ï¿½ï¿½C in July 2015 while the average ambient temperature for this month was 30ï¿½ï¿½C. ï¿½ 2016 Elsevier Ltd