As the pace of technological advances accelerates, the role of electrical energy storage has become increasingly important. Among various storage solutions, supercapacitors are garnering significant attention. Their unique attributes, including high power density, rapid charge/discharge capabilities, and extended lifecycle, position them as a promising alternative to conventional batteries. This study investigates the synthesis of a nickel oxide (NiO) and nickel oxide/graphene oxide (NiO/GO) composite using a single-step hydrothermal method, to evaluate their potential as supercapacitor electrode materials. The synthesized NiO, graphene oxide (GO), and NiO/GO composite were comprehensively characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy to analyze their crystal structures and chemical bonding. The XRD analysis confirmed the formation of an NiO phase with a rhombohedral crystal structure, and no change after GO incorporation. SEM analysis revealed the formation of spherical NiO particles and porous morphology of the NiO/GO composite, which also exhibited a spherical shape. The GO displayed a randomly arranged wrinkled sheet-like structure. Electrochemical analysis of the NiO/GO composite exhibited a remarkable specific capacitance of 893 F g-1 at a current density of 1 A g-1, surpassing that of NiO and GO alone, demonstrating NiO/GO has promising performance for supercapacitor applications. The charge transfer resistance, derived from the Nyquist plot, suggests that the reduction in charge transfer resistance contributed significantly to the improved capacitance. Additional stability studies of over 5,000 cycles at 5 A g-1 revealed an 85 % initial capacitance retention, confirming the advantages of GO inclusion to improve material retention for superior long-term performance. The asymmetric supercapacitor (ASC) assembled using an electrode with the configuration NiO/GO//activated carbon (AC) showed a specific capacitance of 77.8 F g-1 obtained at a current density of 0.5 A g-1.

Hydrogen production via photoelectrochemical water splitting relies on the effectiveness of the photoelectrodes. Preparing low-dimensional structures of oxide semiconductors is a promising approach to fabricating effective photoelectrodes, by enhancing the surface-to-volume ratios of the photocatalytic materials. In this study, we performed a comparative investigation of the photoelectrochemical characteristics of p-type oxide semiconductor cupric oxide (CuO) photocathodes based on CuO thin film and nanorods. The CuO thin film was prepared via a facile method involving sputtering a Cu metallic film and subsequent thermal oxidation, while the CuO nanorods were grown via a seed-mediated hydrothermal synthesis method using a CuO nanoparticle seed layer. The structural, optical, and photoelectrochemical properties of the prepared CuO thin film and nanorods were comparatively examined. Our results confirmed that the CuO nanorod photocathode has a higher photocurrent density and better photoconversion efficiency than the CuO thin film photocathode for photoelectrochemical water splitting, implying a promising route to the fabrication of CuO-based photoelectrodes.

Genetic algorithms (GAs) are used to optimize solutions to problems, particularly those that are analytically impossible to solve. As their name suggests, they are inspired by the biological concepts of genetics and evolution. Our work aims to study and model a silicon-based photovoltaic generator (PVG). Among the various models available is that of the diode. Modeling was used to approximate the PVG output (voltage, current) as a function of two inputs: temperature and irradiation. The parameters of our model were identified using a real coding algorithm, with the cumulative square error was used for selection. To test the effectiveness of our model, we carried out simulation tests on the power-voltage (P-V) and current-voltage (I-V) characteristics of a wide range of irradiation and temperature variations. This study demonstrates the effectiveness and accuracy of the proposed approach (GAs) and validates the parameters obtained and used in the single-diode electrical model. The results indicate that the GA technique is a better conventional parameter extraction strategy in terms of convergence. It provides globally optimal solutions.

Component-specific information is crucial for identifying sources of PM2.5 in indoor environments. However, profiles of PM2.5 at various locations, including subway tunnels are limited. This study aimed to evaluate the relationships between PM2.5 and its component across tunnels, platforms, and outdoor environments at underground subway stations in Incheon. The study was conducted at six underground subway stations in Incheon. PM2.5 concentrations were measured twice at each station, simultaneously covering the tunnel, platform, and outdoor areas. Carbon (two types), ion (eight types), and metal components (20 types) were analyzed using each analytical instruments. The mean PM2.5 concentration in the tunnel was 33.0±15.7 μg/ m3, significantly higher than the concentrations observed on the platform (12.9±4.6 μg/m3) and outdoors (13.1±7.6 μg/m3). The proportion of total metal concentrations in PM2.5 was highest in the tunnel (57.8%), followed by the platform (22.2%) and outdoor areas (11.3%). Significant correlations between the platform and tunnel were observed for organic carbon, SO4 2–, NO3 –, NH4 +, Ba, Mn, Fe, and Se. Significant correlations between the platform and outdoor were observed for SO4 2–, NO3 –, NH4 +, and Ti, while the tunnel and outdoor showed correlations for SO4 2– and NH4 +. PM2.5 concentrations and total metal concentrations were highest in the tunnel. While PM2.5 concentrations on the platform and outdoors were similar, total metal concentrations were higher on the platform than outdoors. From the platform’s perspective, the concentrations of Ba, Mn, Fe, and Se were only associated with the tunnel, while SO4 2–, NO3 –, and NH4 + had tendency of correlations between both the tunnel and outdoors. The findings suggest that for platform PM2.5 concentrations, Ba, Mn, Fe, and Se may serve as indicators of tunnel-originating PM2.5, while SO4 2–, NO3 –, and NH4 + may serve as indicators for outdoor sources.

The Indoor Air Quality Control Act aims to regulate indoor air quality (IAQ) to safeguard public health and promote a comfortable living environment. This law encompasses multi-use facilities, newly constructed residential complexes, and public transportation vehicles. The law also involves mandating air quality standards, conducting periodic measurements, and transparent public reporting of results. Over time, the Indoor Air Quality Control Act has expanded to enforce stricter controls on building materials and enhance radon mitigation measures. In doing so, it embodies the principles of the Environmental Policy Basic Act and is supported by other laws, policies, and systems related to air quality management. In line with these efforts, local governments have been implementing IAQ initiatives tailored to regional needs, including consulting services and financial support. However, challenges persist in harmonizing management across diverse facilities due to overlapping responsibilities among laws and government bodies. Future recommendations emphasize integrated strategies and enhanced inter-agency coordination to address these gaps effectively, ensuring healthier indoor environments for all stakeholders.

This review paper provides a comprehensive analysis of the measurement and distribution of microplastics in the atmosphere and their role in the adsorption and transport of organic and inorganic pollutants. Due to their small size, large surface area, and hydrophobic nature, microplastics can adsorb a wide range of pollutants, including volatile organic compounds (VOCs) and heavy metals. These pollutants, strongly bound to the surface of microplastics, can remain suspended in the atmosphere for extended periods, facilitating the widespread distribution of contaminants. Building on existing research, this paper systematically reviews the sampling, pretreatment, and analytical methodologies applied to study microplastics in the air. Furthermore, it examines the influence of environmental factors on the adsorption and desorption dynamics of pollutants associated with microplastics. Various studies indicate that microplastics can interact with pollutants such as heavy metals, organic compounds, and microorganisms to form complex contaminants. These complexes can be transported and redistributed across long distances in the atmosphere, amplifying their environmental and health impacts. This review highlights that microplastics are not merely a pollutant themselves but serve as a vehicle for the migration and dispersion of other contaminants. This dual role emphasizes the significant risks microplastics pose to public health and the environment, necessitating further research and effective mitigation strategies.

Due to the onset of urbanization worldwide, there is an increasing demand for improving the quality of the urban environment. Odor in wastewater collection systems (WCSs) can interfere with the comfortable and safe living conditions of citizens. Additionally, it can cause economic losses, such as the corrosion of wastewater collection facilities. In this paper, the mechanism of odor generation in WCSs was summarized, and the odor concentrations and sulfide generation rates measured in domestic and foreign WCSs were comprehensively analyzed to review the characteristics of odor emission in WCSs. The complex odor intensity (dilution-tothreshold value) measured in combined domestic sewers ranged from 10 to 10,000, with a median of 100. The odorous compound with the highest contribution to complex odor intensity was hydrogen sulfide, which was the odor most frequently detected at the highest concentrations in most WCSs (its median and mean concentrations were 378.0 ppb and 3,771.2 ppb, respectively). The odor emission properties in the WCSs in Australia and Finland were similar to those of South Korea, with the median and mean concentrations of hydrogen sulfide being 1,927.5 ppb and 12,306.1 ppb, respectively. The sulfide generation rates measured in domestic and foreign WCSs ranged from 0.003 to 0.220 g m–2 h–1. In addition, the key factors affecting sulfide generation were sulfate and organic matter concentrations, pH, temperature, flow rate (retention time), dissolved oxygen concentration, and electron acceptor concentrations other than sulfate. To control odor in WCSs, various methods have been proposed to improve their anaerobic environment. These include sucking outside air into the WCSs and improving their hydraulic conditions, such as changing the slope of sewer pipes to minimize sediment deposition. Additionally, periodically removing sediments, which contain a significant amount of organic matters and sulfate-reducing bacteria, is also a useful method for controlling odor in WCSs. Since the odor compounds that contribute the highest odor intensity–and are the most frequently detected–are sulfur-containing odors such as hydrogen sulfide, the control of sulfides is crucial for controlling odor in WCSs. There are chemical control methods for the mitigation of sulfide in WCSs, including air (oxygen) injection and introducing various chemicals, such as alkalis, nitrates, iron salts, and biocides. However, most of the results of odor control using these methods were from laboratory-scale studies. Therefore, additional field-scale experiments should be conducted in WCSs to evaluate the actual effectiveness of various odor control methods. Through these field studies, the optimal conditions for each method to control odor in WCSs can be derived, and the efficiency and economic feasibility of each method can be verified.

This study was carried out to get information on the concentration and species of airborne fungi in wood ear mushroom (Auricularia heimuer) cultivation houses. Air samplings were conducted at three wood ear mushroom farms located in Iksan and Wando in 2022. Two out of the three cultivation houses exceeded the Ministry of Environment’s recommended indoor air quality standards for fungi concentration in multi-use facilities. A total of 12 genera and 15 species of airborne fungi were isolated and identified. There were species belonging to 6 genera at the genus level. Overall, the genus Cladosporium accounted for the majority with three species. Among the identified species, there were fungi that affect the human body, such as Aspergillus niger, Lichtheimia ramose, and Rhizomucor pusillus, as well as Alternaria alternata, Cladosporium ramotenellum, Cladosporium subuliforme, and Curvularia lunata, which cause diseases in plants. Penicillium brevicompactum was detected as a fungus affecting mushroom cultivation. This study is the first report in Korea on airborne fungi in wood ear cultivation houses and provides useful information for environmental hygiene management of cultivation houses.

The management of pollutant emissions from industrial sites involves various crucial steps, including estimating emission quantities and assessing their impact on surrounding areas. While emissions from point sources, such as exhaust outlets, are relatively easier to manage, emissions from area sources, such as workshops and livestock facilities, are often challenging to measure due to various constraints. To address this issue, this study proposes a method for estimating emissions from area sources by utilizing data collected at site boundaries and applying a reverse modeling approach. Using data from actual livestock facilities, along with reverse modeling results, this study identified a strong correlation between the facility area and the number of livestock raised. Correlation analyses revealed positive relationships between the facility area and the average odor emission rate, as well as between the number of livestock and the average odor emission rate. In addition, the results of reverse modeling confirmed a significant correlation between odor emissions, the number of livestock, and the facility area. Based on these findings, this study developed an odor emission factor for livestock facilities using the number of livestock and the facility area as activity indicators. The odor emission factor is expressed in units of OU/s/pig/m², where “OU” represents odor units, “s” denotes seconds, “pig” corresponds to the number of livestock, and “m²” refers to the total facility area. By multiplying the number of livestock by the facility area, the total odor emission rate (OU/sec) can be calculated. Unlike traditional emission factors that rely solely on the number of livestock, this newly developed factor incorporates all facilities contributing to odor emissions within a livestock operation. This approach allows for the estimation of odor emissions using external measurement data and facility information, even in cases where direct measurements are impractical. The results of this study are expected to be effectively utilized for odor evaluation and management in livestock facilities.

This study presents an integrated indoor air quality index (IAQI) algorithm aimed at enhancing the efficiency of indoor air quality management in diverse indoor environments. The proposed IAQI accounts for the combined effects of multiple pollutants, offering a more comprehensive approach than traditional concentrationbased methods. Findings from four exposure scenarios and probabilistic health risk assessments indicate that the IAQI can be tailored to reflect occupant characteristics and space usage, thereby providing improved protection for sensitive populations, such as newborns. The application of occupant-specific criteria led to reductions in pollutant concentrations and associated health risks compared to conventional standards. Furthermore, the IAQI incorporates correction factors and weighted adjustments, facilitating robust risk assessments in complex multi-pollutant contexts. By addressing the limitations of single-pollutant management, this approach supports the development of more effective strategies for indoor air quality control. The proposed algorithm holds significant potential for practical applications in indoor air quality management and policymaking. Future research should focus on validating its effectiveness across a wider range of indoor environments.

This study aims to prepare bamboo-based activated carbons with surface modifications, focusing on carbon dioxide (CO2) capture in public indoor spaces. The surface of the activated carbon adsorbents was chemically modified through three steps: carbonization, steam activation, and chemical treatment using potassium hydroxide (KOH) and potassium sulfamate (KSO3NH2). The specific surface area and pore volume of the obtained adsorbent (BSAC-KN) were 1,246 m2/g and 0.74 cm3/g, respectively. The surface modification resulted in an adsorption capacity of up to 3.79 mmol-CO2/ g-AC for carbon dioxide. In addition, the expansion of the specific surface area and the enhanced physico-chemical interaction between the weak acidic CO2 molecules and the basic AC surface improved adsorption capacity.

The purpose of this study was to verify the radon reduction effectiveness of some radon barrier paints using the laboratory test on radon exhalation rate. The radon exhalation characteristics and radon exhalation rate of three radon barrier paints for concrete and three radon barrier paints for stone finishes were evaluated before and after application. Then the radon reduction rate was calculated to confirm the reduction effects. The results showed that the radon reduction rate of radon barrier paint was less than 10%, which is not effective in reducing radon. These findings suggest that a reliable radon reduction evaluation method is needed to utilize radon barrier paints as an indoor radon control measures.

Following the implementation of the Act on the Prevention of Light Pollution Due to Artificial Lighting in 2013, local governments designated lighting environment management zones and conducted assessments of the impacts of light pollution on the environment to ensure compliance with acceptable light emission standards. In addition, according to the Act on the Prevention of Light Pollution Due to Artificial Lighting, local governments conduct and manage light pollution assessments every three years. However, measuring and analyzing during nighttime requires a significant amount of time and labor. Therefore, this research aims to improve the current light pollution environmental impact assessment method by utilizing aerial information from satellite data and establishing a database of light pollution assessment methods, thereby laying the foundation for light pollution management. In this study, a reference light source was installed on the ground, and the luminance measurements of the installed reference light source and the advertising light sources on-site were analyzed to derive brightness values for ground light sources using the optical band (R, G, B) values from aerial information derived from satellite images. The analysis produced predictive equations for light pollution from upward lighting and general advertising lighting. When these equations were applied to residential and commercial areas in the lighting environment management area, the results indicated that the predicted rooftop upward lighting prediction brightness exceeded the acceptable standard of light emission of 800 cd/m2 in residential areas, and the advertisement lighting prediction brightness exceeded the standard of 1,000 cd/m2 in commercial areas.

Indoor air quality is a critical factor affecting health and quality of life, especially in spaces frequently used by sensitive populations such as adolescents. This study assessed the impact of garden ball installations and electrochemical fertilizer applications on indoor air quality in two youth centers, Center S and Center W, located in Bucheon, South Korea. PM2.5, PM10, and CO2 concentrations were monitored and analyzed based on the presence of garden balls and the use of electrochemical fertilizers. The results showed that spaces with garden balls (w/ G.B.) had significantly lower PM2.5 and PM10 concentrations compared to offices and spaces without garden balls (w/o G.B.). In Center W, the presence of garden balls alone improved air quality, highlighting the potential of vertical greening as a sustainable solution. In Center S, the application of electrochemical fertilizers during the “after + period” (when both garden balls and electrochemical fertilizers were applied) further enhanced particulate matter reduction, demonstrating the fertilizers’ ability to amplify plants’ air-purifying effects. This study provides empirical evidence that garden balls are an eco-friendly option for indoor air quality management. Combining electrochemical fertilizers with garden balls shows promise for enhancing air quality, offering a practical model for multi-use facilities such as youth centers.

This study sought to improve the accuracy of estimating national emissions of volatile organic compounds (VOCs) from consumer solvent products (CSPs) by updating emission factors and category-specific activity data. The classification of the CSPs, which was originally proposed by the U.S. Environmental Protection Agency, was reorganized to reflect domestic consumption patterns in Korea. VOC contents, product sales, and atmospheric evaporation rates of the CSPs were analyzed for subcategories including personal care products, household products, and automotive aftermarket products to update their emission factors. Additionally, the category-specific activity data, previously based on only population statistics, were newly applied to count the characteristics of each classification, such as the number of households and the number of registered automobiles. The updated emission factors were calculated to be 1.90 kg/capita·yr for personal care products, 4.37 kg/household·yr for household products, and 2.36 kg/car·yr for automotive products. An evaluation of uncertainties revealed the limitation in the product classification, the shortage of sales data, and the lack of information on VOC contents depending on the product forms (liquid, solid, and aerosol). This study highlighted the necessity of developing detailed classification systems and standardized VOC content measurement methods, ultimately contributing to more accurate and practical assessments of VOC emissions from the CSPs.

Mold caused by indoor temperature and humidity is related to inflammatory reactions such as rhinitis, asthma, and allergic skin diseases. The subjects were children aged 3-7 in Seocheon-gun, Chungcheongnam-do. For indoor environmental measurement, a mold collection medium was installed on the sampling device and samples were collected at 28.3 L/min for 7 minutes. The sampling device was installed at a height of 1.2 m to 1.5 m above the ground to collect samples. The demographic characteristics of the children in the 90 households that participated in the survey were 53 males (58.9%) and 37 females (41.1%). The majority of the children were 5 years old (26 people or 28.9%), followed by 6 year olds (23 people or 25.6%), 7 year olds (18 people or 20.0%), 4 year olds (18 people or 20.0%), and 8 year olds (5 people or 5.6%). Among the characteristics listed on the questionnaire, 11 children (12.2%) were diagnosed with asthma, and 63 subjects (70%) had not been diagnosed by a doctor in the past 12 months. Regarding symptoms exhibited by the parents, 4 fathers (4.5%) and 2 mothers (2.2%) had symptoms. In the relationship between asthma and the concentration of other indoor environmental substances, the average concentration of mold was 57.0 CFU/m3 for non-asthmatics and 14.5 CFU/m3 for asthmatics, showing a statistically significant difference. The average concentration of house dust mites was 338.9 ng/g in non-asthmatics and 79.5 ng/g in asthmatics, showing a statistically significant difference.

Along with the increase in the number of vehicles in circulation, the indoor air quality in automobiles is attracting attention as another possible health concern. However compared to data regarding indoor air quality in other spaces, there are insufficient data on indoor air quality in automobiles. In addition, there is no standard for the evaluation method. In this study, the change in the concentration of particulate matter in the vehicle while driving under real road conditions was analyzed in order to use it as basic data for a method to evaluate vehicle indoor air quality. Through the selection of measurement target materials and test vehicles and the preparation of test methodologies, evaluation was performed on vehicle, route, and HVAC modes. The concentration of particulate matter in the vehicle was the lowest in the RC (In-vehicle recirculation) condition, and it was confirmed that it decreased with time. The highest average concentration was confirmed in the OA (Outside air ventilation) condition, and the concentration change according to the changing HVAC mode was observed in the Auto condition. The concentration of pollutants inside the vehicle showed a significant correlation with factors such as season, external concentration, and HVAC conditions, along with a weak correlation to powertrain type. The results of this study can be used as basic data for developing methods for evaluating vehicle interior air quality in future work.

The focus of this study was on the preparation of a clinoptilolite-based adsorbent, utilizing natural zeolite, to adsorb and remove ammonia (NH3) emitted from various environmental facilities, and to evaluate its performance. To create an adsorbent suitable for humid environments, hydrophobicity was introduced through HCl acid treatment. The impact of acid concentration and treatment time was analyzed to optimize the preparation conditions. As a result, the adsorbent treated with 0.5 M HCl for 2 hours demonstrated the highest NH3 adsorption performance. These findings suggest that the developed adsorbent could serve as an effective solution for controlling NH3 emissions in humid environments, contributing to the mitigation of environmental pollution and odor issues.

This study was conducted to efficiently manage THC, which was previously managed only through self-measurement. Using Selected Ion Flow Tube Mass Spectrometers, a real-time air quality measurement device, VOCs were measured in five industrial complexes, and methyl ethyl ketone was measured at the highest concentration in the industrial complexes. THC measurements were conducted at business sites located in the area. As a result of the measurements, printing processes, drying processes, etc. exceeded the emission standard of 110 ppm in three processes, and the outlets that exceeded the emission standard were instructed to improve prevention facilities such as activated carbon replacement, thereby reducing highconcentration VOC emissions. The results of the study suggest that if inspection agencies measure VOCs in real time and conduct Total Hydro Carbon measurements, etc. mainly in high-concentration areas, VOCs and Total Hydro Carbon, which are the causes of greenhouse gases and odors, can be efficiently reduced.

Objectives: The main purpose of this study was to identify problems such as cooking fumes and lack of ventilation in school cafeterias and evaluate the improvement in the reduction of indoor pollutants in the cooking rooms through renovation. Methods: Three schools were selected for renovation and the spatial structures and air conditioning system of the cafeterias and cooking rooms wre investigated after renovation. The air conditioning systems were improved by the renovation work according to the characteristics of each school, and the concentration of indoor pollutants was measured and evaluated through CFD analysis. Results: The concentration of indoor pollutants in the cafeterias and cafe rooms was decreased after renovation. Conclusion: Air conditioning systems in the schools cafeterias and cooking rooms were improved in order to solve the problems of ventilation, and the indoor air quality improvement rate ranged from a minimum of 11% to a maximum of 40%. The renovation of cafeterias and cooking rooms was conducted to optimize the ventilation systems and this contributed to indoor air quality improvement by preventing the inflow of pollutants.