Article
Chemistry, Multidisciplinary
Andres Vignolo, Ana Paula Gomez, Martin Draper, Mariana Mendina
Summary: This paper studies the indoor air quality of a naturally ventilated elementary school classroom, measures parameters such as carbon dioxide concentration, and assesses the airborne risk of SARS-CoV-2 through simulations. The study finds that periodic ventilation significantly reduces the risk, especially in naturally ventilated environments in cold weathers.
APPLIED SCIENCES-BASEL
(2022)
Article
Environmental Sciences
Z. A. Firatoglu
Summary: To reduce the transmission risk of COVID-19 in classrooms, it is important to develop new ventilation strategies. This study investigated the effect of natural ventilation on airborne transmission of COVID-19-like viruses in a classroom. Results showed that a significant portion of virus-laden droplets settled on the infected student's desk after sneezing, while small droplets continued to move in the airflow. Natural ventilation had negligible impact on virus droplet travel when the Reynolds number was below 8.04 x 104.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Sowoo Park, Younhee Choi, Doosam Song, Eun Kyung Kim
Summary: The World Health Organization warns of airborne transmission of SARS-CoV-2 in poorly ventilated indoor spaces. Ventilation plays a crucial role in reducing the risk of virus transmission. Studies show that opening windows can significantly increase ventilation rates, especially in public buildings and shared spaces.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Construction & Building Technology
Henry C. Burridge, Stavros Bontitsopoulos, Christopher Brown, Holly Carter, Katherine Roberts, Carolanne Vouriot, Dale Weston, Mark Mon-Williams, Natalie Williams, Catherine Noakes
Summary: Seasonal changes in CO2 levels were observed in four schools in the UK, with lower levels during warmer weather and higher levels during colder seasons. A significant reduction in CO2 levels during the latter part of the year compared to a similar cold weather period at the beginning of the year suggests changes in classroom ventilation behaviors.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Alessandro Zivelonghi, Massimo Lai
Summary: Issues related to aerosol physics and infection risk in school buildings are not properly recognized in safety regulations. Precise investigation of ventilation factors and occupancy rates in each classroom is needed, but most schools lack necessary systems and sensors.
BUILDING AND ENVIRONMENT
(2021)
Article
Environmental Sciences
Naohide Shinohara, Jun Sakaguchi, Hoon Kim, Naoki Kagi, Koichi Tatsu, Hiroyuki Mano, Yuichi Iwasaki, Wataru Naito
Summary: The study found that the air exchange rates in train cars are influenced by factors such as the degree of window opening, whether doors are closed, and the speed of the train. Under specific conditions, opening doors and windows and turning on the central air conditioning/fan system can significantly reduce the risk of infection for passengers on trains.
ENVIRONMENT INTERNATIONAL
(2021)
Article
Mechanics
Ruichen He, Wanjiao Liu, John Elson, Rainer Vogt, Clay Maranville, Jiarong Hong
Summary: The study demonstrates that box fan air cleaners can effectively reduce airborne transmission risks in classrooms, significantly lowering aerosol concentration and spread in the entire space when placed in the room. When the location of the patient is unknown, optimal performance can be achieved by placing the cleaner near the HUV, which is more efficient in reducing transmission risks compared to increasing the flow rate of the HUV alone.
Article
Environmental Sciences
Mojtaba Ehsanifar
Summary: Researchers are actively investigating the transmission of the coronavirus, with aerosol transmission considered possible. Precautionary control strategies to effectively reduce virus transmission need to be considered.
ENVIRONMENTAL RESEARCH
(2021)
Article
Multidisciplinary Sciences
Arvin Hekmati, Mitul Luhar, Bhaskar Krishnamachari, Maja Mataric
Summary: This study investigates the airborne transmission risk of conducting in-person classes on university campuses, considering the original strain and a more contagious variant of SARS-CoV-2. The findings suggest that moving classes online and using masks can significantly reduce new cases. However, for the more contagious variant, a high vaccination rate is required even with universal mask usage to ensure safety.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Construction & Building Technology
Bertrand R. Rowe, Andre Canosa, Amina Meslem, Frantz Rowe
Summary: This paper discusses the implications of new COVID-19 variants, such as delta and omicron, on health policies. It provides a clear analytical understanding and modeling of airborne contamination paths, dose-response laws, and the importance of counting units for pathogens. The study emphasizes the inadequacy of current ventilation standards and points out that air can often be considered well-mixed. It suggests that public health policies should consider multiple parameters, including exposure time, pathogen production rate, mask wearing, and the proportion of infectors in the population.
BUILDING AND ENVIRONMENT
(2022)
Article
Construction & Building Technology
Huw Woodward, Rick J. B. de Kreij, Emily S. Kruger, Shiwei Fan, Arvind Tiwari, Sarkawt Hama, Simon Noel, Megan S. Davies Wykes, Prashant Kumar, Paul F. Linden
Summary: Experiments conducted in the UK evaluated the risk of airborne transmission of the SARS-CoV-2 virus on an inter-city train carriage. The risk of infection during a 1-hour train journey was estimated to be significantly lower than a full day in either a well-ventilated or poorly ventilated office.
Article
Engineering, Chemical
Siyao Shao, Dezhi Zhou, Ruichen He, Jiaqi Li, Shufan Zou, Kevin Mallery, Santosh Kumar, Suo Yang, Jiarong Hong
Summary: The lack of quantitative risk assessment of airborne transmission of COVID-19 under practical settings leads to uncertainties and inconsistencies in preventive measures. Ventilation design is critical for reducing the risk of particle encounters, inappropriate design can create hot spots with higher risks and enhance particle deposition causing surface contamination. Faceted particles from normal breathing are correlated with breathing depth.
JOURNAL OF AEROSOL SCIENCE
(2021)
Article
Construction & Building Technology
Brijesh Pandey, Sandip K. Saha, Rangan Banerjee
Summary: This study numerically investigated the effect of airflow induced by ceiling fans and ventilation rates on aerosol distribution to mitigate exposure to airborne pathogens and COVID-19. The study found that increasing ceiling fan rotation speed and ventilation rates can effectively improve aerosol distribution and reduce the risk of airborne pathogen transmission.
INDOOR AND BUILT ENVIRONMENT
(2023)
Review
Environmental Sciences
Zahra Noorimotlagh, Neemat Jaafarzadeh, Susana Silva Martinez, Seyyed Abbas Mirzaee
Summary: The possibility of airborne transmission of SARS-CoV-2 in indoor air environments has been highlighted in the face of the COVID-19 pandemic. Measures such as improving ventilation, maintaining interpersonal distance, and considering the airborne transmission route are crucial for protecting health.
ENVIRONMENTAL RESEARCH
(2021)
Article
Mechanics
Chin Chun Ooi, Ady Suwardi, Zhong Liang Ou Yang, George Xu, Chee Kiang Ivan Tan, Dan Daniel, Hongying Li, Zhengwei Ge, Fong Yew Leong, Kalisvar Marimuthu, Oon Tek Ng, Shin Bin Lim, Peter Lim, Wai Siong Mak, Wun Chet Davy Cheong, Xian Jun Loh, Chang Wei Kang, Keng Hui Lim
Summary: The study proposes a risk assessment method combining computational and experimental approaches to help decision-makers classify scenarios into different risk levels based on simulations and experiments, guiding the opening and lockdown of activities. Through a case study on a public bus in Singapore, researchers identified the impact of different activities and passenger positions on infection risk, demonstrating the effectiveness of this risk assessment method.
Article
Thermodynamics
Ennio Luciano, Javier Ballester
Summary: The study thoroughly examines the application of the cross-correlation method (CCM) in analyzing the dynamic response of premixed methane and biogas flames, revealing that vortex shedding governs the dynamics of the flames studied. Different responses to fluctuations were observed in methane and biogas flames, with changes in the location of regions with the strongest response to velocity fluctuations. The perturbations were found to travel along the flame at approximately one half of the flow velocity, consistent with recent findings.
COMBUSTION SCIENCE AND TECHNOLOGY
(2021)
Article
Thermodynamics
Alvaro Muelas, Jaime Carpio, Javier Ballester, Antonio L. Sanchez, Forman A. Williams
COMBUSTION AND FLAME
(2020)
Article
Thermodynamics
Ennio Luciano, Jesus Oliva, Alvaro Sobrino, Javier Ballester
Summary: This work presents the first characterization study of a novel approach called pseudo-active instability control (PAIC), which offers the versatility of active control with simpler hardware requirements. Experimental results demonstrate the potential of this approach and reveal the acoustic interactions between the burner and the pilot line in influencing the limit cycle.
COMBUSTION SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
A. Muelas, P. Remacha, A. Pina, J. Barroso, A. Sobrino, D. Aranda, N. Bayarri, C. Estevez, J. Ballester
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2020)
Article
Energy & Fuels
Alvaro Muelas, Diego Aranda, Maria Soledad Callen, Ramon Murillo, Alberto Veses, Mohamad Asrardel, Javier Ballester
Article
Energy & Fuels
Saul Laguillo, Jose Salvador Ochoa, Eduardo Tizne, Antonio Pina, Javier Ballester, Alfredo Ortiz
Summary: The study aims to investigate the CO formation and its relationship with flame structure during natural gas burning in simplified burners. Experimental tests and numerical modeling were conducted to analyze the influence of burner-to-pot distance, flame thermal power, primary aeration, and inside-pot water temperature on CO emissions and thermal efficiency. The results show that primary aeration or wall temperature increases can reduce CO emissions, while changes in burner-to-pot distance or flame thermal power may lead to non-monotonic trends.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)
Article
Thermodynamics
Alvaro Muelas, Diego Aranda, Javier Ballester
Summary: The development of simplified surrogate mixtures is crucial for simulating chemically complex fuels and designing efficient and clean combustion applications. This study proposes using isolated droplet configuration to formulate and validate surrogates that replicate the vaporization and soot production characteristics of diesel and diesel-biodiesel mixtures. The results show that the proposed surrogate blends match well with the target fuels in terms of evaporation behavior and soot tendency, indicating the validity of the methodology. However, further validation revealed higher soot yields for the surrogates compared to the target fuels, emphasizing the importance of the configuration used in designing and validating surrogates.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Mohamad Asrardel, Alvaro Muelas, Javier Ballester
Summary: This study proposes a systematic methodology to formulate surrogates for fuel droplet evaporation behavior. The methodology includes a sensitivity analysis to assess the impact of physical properties, a pseudo-component approach to characterize the fuel, and a multi-objective genetic algorithm to optimize the surrogate composition. The results show that the surrogates designed following this systematic methodology exhibit remarkable similarity to the target fuels.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Environmental Sciences
Muhammad Waqas, Majid Nazeer, Man Sing Wong, Wu Shaolin, Li Hon, Joon Heo
Summary: The socio-economic restriction measures implemented in the United States have significantly reduced nitrogen dioxide (NO2) emissions. The study highlights the impact of factors such as human mobility, population density, income, climate, and stationary sources on the reduction of NO2 at different stations. The research emphasizes the scientific impacts of the NO2 reduction and income inequality revealed by the pandemic on air quality and health disparities.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Guorui Zhi, Jinhong Du, Aizhong Chen, Wenjing Jin, Na Ying, Zhihui Huang, Peng Xu, Di Wang, Jinghua Ma, Yuzhe Zhang, Jiabao Qu, Hao Zhang, Li Yang, Zhanyun Ma, Yanjun Ren, Hongyan Dang, Jianglong Cui, Pengchuan Lin, Zhuoshi He, Jinmin Zhao, Shuo Qi, Weiqi Zhang, Wenjuan Zhao, Yingxin Li, Qian Liu, Chen Zhao, Yi Tang, Peng Wei, Jingxu Wang, Zhen Song, Yao Kong, Xiangzhe Zhu, Yi Shen, Tianning Zhang, Yangxi Chu, Xinmin Zhang, Jiafeng Fu, Qingxian Gao, Jingnan Hu, Zhigang Xue
Summary: An comprehensive emission inventory for China in 2019, which includes both air pollutants and greenhouse gases, was developed in this study. The inventory utilizes existing frameworks and data to provide comparable emissions data and demonstrates the relationship between emissions and economic development.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
I-Ting Ku, Yong Zhou, Arsineh Hecobian, Katherine Benedict, Brent Buck, Emily Lachenmayer, Bryan Terry, Morgan Frazier, Jie Zhang, Da Pan, Lena Low, Amy Sullivan, Jeffrey L. Collett Jr
Summary: Unconventional oil and natural gas development (UOGD) in the United States has expanded rapidly in recent decades, raising concerns about its impact on air quality. This study conducted extensive air monitoring during the development of several large well pads in Broomfield, Colorado, providing a unique opportunity to examine changes in local air toxics and VOC concentrations during well drilling and completions and production. The study identified significant increases in VOC concentrations during drilling operations, highlighting the importance of emissions from synthetic drilling mud. The findings suggest opportunities to mitigate emissions during UOGD operations.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Puji Lestari, Akbar R. Tasrifani, Wiranda I. Suri, Martin J. Wooster, Mark J. Grosvenor, Yusuke Fujii, Vissia Ardiyani, Elisa Carboni, Gareth Thomas
Summary: This study developed field emission factors for various pollutants in peatland fires and estimated the total emissions. Gas samples were collected using an analyzer, while particulate samples were collected using air samplers. The study found significant emissions of CO2, CO, PM2.5, carbon aerosols, water-soluble ions, and elements from the fires in Central Kalimantan, Indonesia in 2019.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Ligang Li, Yuyu Chen, Lu Fan, Dong Sun, Hu He, Yongshou Dai, Yong Wan, Fangfang Chen
Summary: A high-precision retrieval method based on a deep convolutional neural network and satellite remote sensing data is proposed to obtain accurate methane vertical profiles.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Hyung Joo Lee, Toshihiro Kuwayama, Michael Fitzgibbon
Summary: This study investigated the changes in nitrogen dioxide (NO2) air pollution levels and their disparities in California, U.S. during the pandemic of coronavirus disease 2019 (COVID-19). The results showed a decrease in NO2 concentrations, especially in urban and high-traffic areas. However, socially vulnerable populations still experienced higher levels of NO2 exposure. The study suggests that reducing NO2 disparities, particularly racial inequity, can be achieved through continued regulatory actions targeting traffic-related NOx emissions.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Maria Chiara Pietrogrande, Beatrice Biffi, Cristina Colombi, Eleonora Cuccia, Umberto Dal Santo, Luisa Romanato
Summary: This study investigates the chemical composition and oxidative potential of PM10 particles in the Po Valley, Italy, and demonstrates the impact of high levels of atmosphere ammonia. The rural area had significantly higher ammonia concentrations compared to the urban site, resulting in higher levels of secondary inorganic aerosol. Although the SIA components did not contribute significantly to the PM10 oxidative reactivity, they were correlated with the oxidative potential measurements. This suggests that the contribution of SIA to PM oxidative toxicity cannot be ignored.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Natalie Allen, Jan Gacnik, Sarrah M. Dunham-Cheatham, Mae Sexauer Gustin
Summary: Accurate measurement of atmospheric reactive mercury is challenging due to its reactivity and low concentrations. The University of Nevada, Reno Reactive Mercury Active System (RMAS) has been shown to be more accurate than the industry standard, but has limitations including long time resolution and sampling biases. Increasing the sampling flow rate negatively affected RM concentrations, but did not impact the chemical composition of RM captured on membranes.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Chin-Yu Hsu, Wei-Ting Hsu, Ching-Yi Mou, Pei-Yi Wong, Chih-Da Wu, Yu-Cheng Chen
Summary: This study estimated the daily exposure concentrations of PM2.5 for elderly individuals residing in different regions of Taiwan using land use regression with machine learning (LUR_ML) and microenvironmental exposure (ME) models. The accuracy of the models varied across regions, with the ME models exhibiting higher predictions and lower biases. The use of region-specific microenvironmental measurements in the ME model showed potential for accurate prediction of personal PM2.5 exposure.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Xiaohan Si, Kerrie Mengersen, Chuchu Ye, Wenbiao Hu
Summary: This study found that there is an interactive effect between air pollutants and weather factors, which significantly affects influenza transmission. Future research should consider the interactive effects between pollutants and temperature or humidity to evaluate the environment-influenza association.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Luxi Xu, Ruijun Xu, Yunshao Ye, Rui Wang, Jing Wei, Chunxiang Shi, Qiaoxuan Lin, Ziquan Lv, Suli Huang, Qi Tian, Yuewei Liu
Summary: This study aimed to evaluate the impact of ambient air pollution on hospital admissions for angina. The results showed that exposure to ambient particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone are associated with an increased risk of hospital admissions for angina. The association with nitrogen dioxide exposure was found to be the strongest.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Xinyu Yu, Man Sing Wong, Majid Nazeer, Zhengqiang Li, Coco Yin Tung Kwok
Summary: This study proposes a novel method to address the challenge of missing values in satellite-derived AOD products and creates a comprehensive daily AOD dataset for the Guangdong-Hong Kong-Macao Greater Bay Area. By reconstructing missing values and developing a new model, the derived dataset outperforms existing products and agrees well with ground-based observations. Additionally, the dataset exhibits consistent temporal patterns and more spatial details.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Yidan Zhang, Yifan Xu, Bo Peng, Wu Chen, Xiaoyu Cui, Tianle Zhang, Xi Chen, Yuan Yao, Mingjin Wang, Junyi Liu, Mei Zheng, Tong Zhu
Summary: This study developed a sensitive method to measure the metallic components of atmospheric fine particulate matter (PM2.5) and compared the results with different analysis methods. The concentrations of metallic components in personal PM2.5 samples were found to be significantly different from corresponding fixed-site samples. Personal sampling can reduce exposure misclassifications, and measuring metallic components is useful for exploring health risks and identifying sources of PM2.5.
ATMOSPHERIC ENVIRONMENT
(2024)
Review
Environmental Sciences
Jamie Leonard, Lea Ann El Rassi, Mona Abdul Samad, Samantha Prehn, Sanjay K. Mohanty
Summary: Increasing concentrations of microplastics in the Earth's atmosphere could have adverse effects on ecosystems and human health. The deposition rate of airborne microplastics is influenced by both land use and climate, and a global analysis suggests that climate may have a greater impact on the concentration and deposition rate of microplastics than land use.
ATMOSPHERIC ENVIRONMENT
(2024)
Article
Environmental Sciences
Tian Zhou, Xiaowen Zhou, Zining Yang, Carmen Cordoba-Jabonero, Yufei Wang, Zhongwei Huang, Pengbo Da, Qiju Luo, Zhijuan Zhang, Jinsen Shi, Jianrong Bi, Hocine Alikhodja
Summary: This study investigated the long-range transport and effects of North African and Middle Eastern dust in East Asia using lidar observations and model simulations. The results showed that the dust originated from multiple sources and had a long transport time. The vertical distribution of the dust was found to be crucial for assessing its impacts.
ATMOSPHERIC ENVIRONMENT
(2024)