Coal mining subsidence areas are a special and widespread ecosystem in China and many developing countries in the world. However, limited research has focused on HCHs and DDTs in coal mining subsidence areas. Investigating the concentration, distribution, and sources of HCHs and DDTs at the Yangzhuang coal mining subsidence area in Huainan, China, is the object of this study. Water samples from different depths were collected from this region to detect and analyze HCHs and DDTs using gas chromatography–mass spectrometry. The result showed that the concentrations of HCHs and DDTs increased with increasing water depth, and the average concentrations of HCHs and DDTs in the top (T-layer), middle (M-layer), and bottom (B-layer) layers were 152, 169, and 182 ng∙L⁻¹, respectively. Spatial distribution of HCH and DDT concentrations in the study area revealed that the concentrations gradually decreased in the direction of water flow, and the highest concentration was observed at the entrance of the Nihe River. The T-layer was easily influenced by environmental and human activities, while the M-layer and B-layer were mainly influenced by sediment. Using principal component analysis and diagnostic ratios, we found that HCHs and DDTs in the study area mainly originated due to natural and human activities (such as pesticide use). Hexachlorocyclohexanes (HCHs) were mainly derived from lindane, and dichlorodiphenyltrichloroethanes (DDTs) mainly originated due to the recent agricultural use of dicofol; both of these are directly related to agricultural activities. Based on a comparison of reported concentrations of HCHs and DDTs in the rivers and lakes throughout China, we found that the overall ecological risk of HCHs and DDTs in the study area was elevated. The results are important for further understanding the transfer characteristics of HCHs and DDTs as well as the ecological health of the water in coal mining subsidence areas.

This study focused on the total mercury content in fish from seven drinking-water reservoirs located in the Morava River Basin: Bojkovice, Boskovice, Hubenov, Karolinka, Landstejn, Ludkovice and Nova Rise in the Czech Republic. A total of 308 fish were collected for the analysis. The content of total mercury was measured in the muscle tissue of bream, roach and perch using atomic absorption spectrometry and varied from 0.057±0.009 to 0.440 mg kg⁻¹ in bream, from 0.030±0.005 to 0.393±0.138 mg kg⁻¹ in roach and from 0.092±0.007 to 0.638±0.042 mg kg⁻¹ in perch. The highest total mercury content was found in perch from Landstejn and the lowest was measured in roach from Ludkovice. A positive statistically significant relationship was found between fish weight and total mercury content in fish muscle for almost all species and all sampling sites, except for roach from Ludkovice. A total of 19 samples exceeded the maximum mercury level set by legislation on food contaminants—0.5 mg kg⁻¹ in freshwater fish.

Pr-modified MnOₓ catalyst was synthesized through a facile co-precipitation process, and the results showed that MnPrOₓ catalyst exhibited much better selective catalytic reduction (SCR) activity and SO₂ resistance performance than pristine MnOₓ catalyst. The addition of Pr in MnOₓ catalyst led to a complete NO conversion efficiency in 120–220 °C. Moreover, Pr-modified MnOₓ catalyst exhibited a superior resistance to H₂O and SO₂ compared with MnOₓ catalyst. After exposing to SO₂ and H₂O for 4 h, the NO conversion efficiency of MnPrOₓ catalyst could remain to 87.6%. The characterization techniques of XRD, BET, hydrogen-temperature programmed reduction (H₂-TPR), ammonia-temperature programmed desorption (NH₃-TPD), XPS, TG and in situ diffuse reflectance infrared spectroscopy (DRIFTS) were adopted to further explore the promoting effect of Pr doping in MnOₓ catalyst on SO₂ resistance performance. The results showed that MnPrOₓ catalyst had larger specific surface area, stronger reducibility, and more L acid sites compared with MnOₓ catalyst. The relative percentage of Mn⁴⁺/Mnⁿ⁺ on the MnPrOₓ-S catalyst surface was also much higher than those of MnOₓ catalyst. Importantly, when SO₂ exists in feed gas, PrOₓ species in MnPrOₓ catalyst would preferentially react with SO₂, thus protecting the Mn active sites. In addition, the introduction of Pr might promote the reaction between SO₂ and NH₃ rather than between SO₂ and Mn active sites, which was also conductive to protect the Mn active sites to a great extent. Since the presence of SO₂ in feed gas had little effect on NH₃ adsorption on the MnPrOₓ catalyst surface, and the inhibiting effect of SO₂ on NO adsorption was alleviated, SCR reactions could still proceed in a near-normal way through the Eley-Rideal (E-R) mechanism on Pr-modified MnOₓ catalyst, while SCR reactions through the Langmuir-Hinshelwood (L-H) mechanism were suppressed slightly.

Today, with the expansion of industries and construction activities, attention to environmental issues such as sustainable development, recycling, reuse, etc. becomes important. The global demand for cement production has been increasing. One ton of cement releases about one ton of carbon dioxide into the atmosphere. Also, after freshwater, sand is considered the second natural resource that is consumed.Due to the limited sand resources and the concerns around the environmental issues of cement production, in this study, the use of waste foundry sand (WFS) as an alternative to aggregate in slag-based geopolymer mortars as an alternative to cement has been considered. WFS is a by-product of the foundry industry, which is produced in large quantities and buried in landfills, and slag is the by-product of iron and steel making process which is highly cementitious and high in calcium silicate hydrates (CSH).In this study, the mechanical, durability properties, and environmental assessment of geopolymer mortars using WFS were investigated. The results show that the compressive strength of geopolymer mortars containing treated WFS at the age of 91 days had an increase of 158% compared to cement-based mortars. The adhesion and flexural strength in geopolymer mortars containing treated WFS compared to untreated mortars increased by 145% and 18%, respectively. Toxicity characteristic leaching procedure (TCLP) results showed that the concentration of heavy metals in the leachate WFS, mortars containing treated and untreated WFS, and ground granulated blast-furnace (GGBF) slag was within the standard permitted limitations and WFS is not a hazardous waste.

The goal of this research is to investigate the effect of utilizing selective liquids as absorption filters to prevent PV module overheating by blocking the undesirable part of the spectrum (long wavelength) while allowing the beneficial part of the spectrum (visible light and near infrared) to pass through. The fluids were evaluated on two different panels, and their results were compared to those of a control panel. In this work, two liquids were used and tested: copper sulfate solution (CuSO₄·5H₂O) and distilled water as absorption filter; each was arranged in such a way that it flows evenly over the surface of a PV module through a cavity mounted on the top side of the PV module. In addition, a standard PV panel was employed as a comparison. The average power produced by the PV when pure was used as an optical filter is 31.3%, while it was 11.3% when copper sulfate solution was used compared with base unit. Furthermore, the cooling effect of pure water on the PV was more efficient than that of copper sulfate solution, with an average PV temperature drop of 15% compared with 7.5% when copper sulfate is used compared with the base unit panel’s performance improved by an average of 31.3% when distilled water was used as the absorption filter, compared to the reference panel’s performance, while the copper sulfate solution improved the panel’s performance by an average of 11.3% compared to the reference panel’s performance.

In this study, a total of 42 water samples were collected from Karasu and Pınarbası, which are two drinking water sources feeding the Kahramanmaras city center water distribution network, from sixteen cisterns fed from these water sources and twenty-four tap water receiving water from the cisterns. Radon concentrations and radon inhalation rates of these water samples were determined using a CR-39 passive trace detector. In natural spring water samples, radon concentrations and exhalation rates ranged from 174.7 ±18.7 Bq/m³ to 211.7± 30.7 ±10.7 Bq/m³ and 5.6 ± 0.6 mBq/m²h to 6.8 ± 1.0 mBq/m²h. In cistern water samples, radon concentrations and exhalation rates ranged from 80.6 ± 3.9 Bq/m³ to 303.0 ± 21.8 Bq/m³ and from 2.6 ± 0.1 mBq/m²h to 9.8 ± 0.7 mBq/m²h, respectively. In tap water samples, radon concentrations and exhalation rates ranged from 99.3 ± 5.5 Bq/m³ to 305.8 ±10.7 Bq/m³ and from 3.2 ± 0.2 mBq/m²h to 9.9 ± 0.4 mBq/m²h, respectively. These values are compared to the Environmental Protection Agency of the United States of America (USEPA), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the European Union (EU) Commission, and the World Health Organization (WHO)’s drinking water safe limit values. As a result, it has been determined that these values are far below the recommended safe limit values for drinking water. Also, the results of this study’s radon and exhalation rate tests are compared to those of comparable studies conducted in Turkey and other countries.

This paper examined the nexus between economic growth, energy consumption, urbanization, population growth, and carbon emissions in the BRICS economies from 1990 to 2019. In order to yield valid and reliable outcomes, modern econometric techniques that are vigorous to cross-sectional dependence and slope heterogeneity were employed. From the findings, the studied panel was heterogeneous and cross-sectionally dependent. Also, all the series were first differenced stationary and co-integrated in the long run. The Augmented Mean Group (AMG) and the Common Correlated Effects Mean Group (CCEMG) estimators were employed to estimate the elastic effects of the predictors on the explained variable, and from the output of both estimators, energy consumption worsened environmental quality via high carbon emissions. Also, the AMG estimator affirmed economic growth to be a significantly positive determinant of carbon emissions. However, both estimators confirmed urbanization and population growth as trivial predictors of the emissivities of carbon. On the causal connections amidst the series, there was bidirectional causality between economic growth and carbon emissions, between energy consumption and economic growth, between economic growth and population growth, between energy consumption and urbanization, and between economic growth and urbanization. Lastly, a causation from urbanization to carbon emissions was unfolded. Policy implications are further discussed.

Exploration and development of shale gas generate a lot of water-based drilling cuttings (WDC), which can then be used in concrete engineering. This work studied mix ratio optimization, mechanical properties, leaching characteristics and the microstructure of the WDC concrete. The results showed that the pH and COD values of these WDC were slightly above 9.0 and 60, respectively. All other indices satisfied the first grade standard of Chinese standard GB8978. On the other hand, a moderate amount of WDC can be improved concrete properties, especially its workability and compressive strength. When the water-binder ratio is 0.52 and the sand ratio is 41%, we can obtain C25 strength grade and 130 ~ 140 mm slump grade concrete by adding high efficiency water reducing agent and fly ash. XRD and SEM analysis showed that the silica and aluminum oxide in WDC reacted with calcium hydroxide to form secondary hydration products: C–S–H gel and ettringite, which are conducive to the formation of concrete strength and solidified the heavy metals and other contaminants. EDX analysis found it is known that the hydration products in WDC concrete can bind metal elements well. The environmental leaching test shows that the recycled WDC added to concrete products as aggregate and admixture is very environmentally friendly and sustainable.

Fine particles (especially PM₂.₅ particles) in ambient air can cause irreversible effects on human health. In the present study, seasonal variations in toxicity PM₂.₅ (cell viability and release of pro-inflammatory cytokines) were exposed human lung cells (A549) to concentrations of PM₂.₅ samples in summer (sPM₂.₅) and winter (wPM₂.₅) seasons. Cells were separately exposed to three concentrations of PM₂.₅ (25, 50, and 100 μg/mL) and three times (12 h, 1 and 2 days). We evaluated cell viability by MTT assay [3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide] and liberation of pro-inflammatory cytokines (interleukin-6 and interleukin-8) by the ELISA method. The toxicological results of this study showed that increasing the concentration of PM₂.₅ particulates and contact time with it reduces cell viability and increases inflammatory responses. Seasonal cytotoxicity of PM₂.₅ particles in high-traffic areas at summer season compared to winter season was lower. The lowest percent of viability at 2 days of exposure and 100 μg/mL exposure in the winter sample was observed. Also, PM₂.₅ particles were influential in the amount of interleukins 8 and 6. The average release level of IL-6 and IL-8 in the cold season (winter) and the enormous exposure time and concentrations (2 days–100 μg/mL) was much higher than in the hot season (summer). These values were twice as high for winter PM₂.₅ samples as for summer samples. The compounds in PM₂.₅ at different seasons can cause some biological effects. The samples’ chemical characteristics in two seasons displayed that the PMs were diverse in chemical properties. In general, heavy metals and polycyclic aromatic hydrocarbons were more in the winter samples. However, the samples of wPM₂.₅ had a lower mass quota of metals such as aluminum, iron, copper, zinc, and magnesium. Concentrations of chromium, cadmium, arsenic, mercury, nickel, and lead were more significant in the sample of wPM₂.₅.

The Micro, Small and Medium Enterprises (MSMEs) face numerous environmental challenges encompassing resource and energy conservation; waste generation and disposal; water and air pollution; and so on. As a result, it becomes critical to implement policies, strategies, and technologies that can help in reducing the adverse impacts of manufacturing activities on the environment. In this context, the current study identified 15 critical environmental sustainability indicators to assess the impact of manufacturing activities on the environment by taking a case study of lock manufacturing MSMEs. To understand the interdependence among the selected indicators, the study further utilizes an integrated DEMATEL-MMDE-ISM approach to analyze the inputs of industry professionals. The results of the study highlighted that green product design, which facilitates the product to be disassembled, reused, or recycled and are free from hazardous materials, plays a significant role in enhancing the environmental sustainability of the concerned industry. Green product design significantly affects 12 other indicators out of 15 under consideration; thus, incorporating green practices in the design and development of a product leads to significant improvement in environmental sustainability. The study is expected to aid decision-makers (industry practitioners and academic researchers) to identify strategic areas in order to achieve higher environmental sustainability in manufacturing organizations.