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Air pollution in coastal areas will have a different pattern from mountainous areas due to different wind patterns during the day and night. The city of Semarang, as a representation of urban areas, and Jepara Regency, as a representation of the rural regions, were chosen for this sampling. 24-h fine particulate matter (PM2.5) was collected within 3 months of sampling. In this study, seven metal elements derived from this PM2.5 were quantified using ICP MS. The analytical method used is a descriptive analysis of the obtained metal element data, enrichment factor (EF), Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) modeling and sources pollutant estimation. The results of the study showed that the stannum (Sn) metal was found in almost all study locations. Sn, K, and Fe are the dominant metals found in urban areas, whereas, in rural areas, only the Sn metal is quite abundant. Nevertheless, the results of EF calculations show that the most significant enrichment in both villages and cities is Sn. Allegedly, this enrichment occurred because of dense activity in the transportation sector and metal industry in urban areas, which brought metals to three villages in Jepara Regency. This research can be used as the main reference in determining health risks associated with metal pollution in atmospheric particulate matter.

To well understand the eutrophication process for inland lakes where more lands had been used for agriculture and industry without adequate environmental protections, 9 surface sediments and 1 core sediment in Lake Xian’nv which was located in the middle of Jiangxi Province were chosen. Combined with 210Pb and 137Cs geochronology, nutrient index including total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), Carbon nitrogen ratio (C/N), diatoms assembles and TDI index of eutrophic diatoms were compared quantitatively and conducted to elucidate the eutrophication process using statistical methods. The results showed a total of 155 years from 1863 to 2018 were recorded from the entire sediment core. The nutrient level in 23 centimeters below the surface of the sediment core where was synchronized with reservoir construction indicated TN, TP, TOC, and Carbon nitrogen ratio had been gradually increased since the construction of Dam. In surface sediments, the three diatoms with higher average relative abundance were Achnanthidium minutissimum, Navicula Bory, and Aulacoseira granulata with a value of 54.2 %, 29.4 %, and 15.3 % respectively. Significant changes of the diatom communities from 1955 to 2009 had been recorded, where diatom communities could be classified into four distinct periods. In the first few years after the reservoir was built, the dominant diatoms were epiphytic and benthic diatom communities represented by Navicula cincta、Fragilaria ulna, and Cocconeis placentula in zone I on the bottom floor covered from 1955 to 1961. However, planktonic diatom communities were dominant after 1983 which were mainly constituted by Aulacoseira alpigena、Cyclostephanos dubius、Cyclotella meneghiniana, and Cyclotella radiosa . Both TDI index of eutrophic diatoms and Principal Component Analysis (PCA) revealed the succession from benthic diatoms to planktonic diatoms and changes in nutrient levels.

This study aimed to evaluate the pollution level of Ni, Pb, Cd, V, and Hg in the sediments of Musa Estuary and its four main tributaries namely Majidieh, Zangi, Semaili, and Merimos (collectively known as Mahshahr estuaries) in summer and winter 2019 using sediment quality indices. In each tributary, 4 stations were chosen to represent the estuary condition. One control point was also considered at the mouth of the estuary (17 stations in total). 51 sediment samples were collected using the Van Wien Hydrobius grab sampler and measurements were performed utilizing the ICP-MASS device. The heavy metals concentration was ordered as Ni> Pb> Cd> V> Hg and tributaries followed the order of Majidiyeh> Samaili> Zangi> Merimos> Musa's mouth (control point) in terms of heavy metal concentration in both seasons. Heavy metal concentrations were positively and significantly correlated with electrical conductivity and pH (P <0.05). The potential ecological risk (Er) was low for Ni, Pb, and V, moderate for Cd (except for Musa's mouth in summer (27.33)). Hg had low risk in Zangi Tributary and Musa's mouth in summer and medium risk in other tributaries in winter. The ecological risk index (RI) showed considerable risk in Zangi Tributary and Musa's mouth in both seasons and high risk in Merimos, Majidieh, and Samaili tributaries. According to the pollution load index (PLI), the sediments of Mahshahr estuaries showed no pollution in summer and moderate pollution in Majidiyeh and Smaili tributaries in winter. The Nemro Integrated Pollution Index ranged from 8.62 to 20.04 in summer and 9.15 to 21.53 in winter Mahshahr estuaries which indicate its high pollution potential. The findings of this research and those of previous studies alarm increasing levels of heavy metals’ content in the sediments of Mahshahr estuaries over the past years.

The biogas production of pretreated corn stover has been determined in different soaking durations. Batch anaerobic digestion applies three different soaking durations in sulfuric acid pretreatment under room temperature. The study aimed to probe the effect of soaking durations during sulfuric acid pretreatment. The experiment was conducted in 600 mL digesters at room temperature. Biogas volume was measured using the water displacement method every three days. The observed cumulative biogas yields varied between 48.74 mL/g VS and 99.95 mL/g VS. The highest biogas yield was obtained when corn stover was soaked in sulfuric acid for 6 hours. The 24 h-pretreated corn stover got the lowest biogas yield. The statistical result proved a significant effect of soaking durations on biogas production (p < 0.05). The logistic model provided a better fit than the first-order model, with R2 values ranging from 0.9923 to 0.9987 and divergence between experimental and predicted values varying between 0.12% and 1.48%.

Concrete is the broadly adopted composite material in the construction arena. The growing need for cost-effective housing is resulting in the depletion of environmental resources such as river sand and gravel, which are essential components in the manufacture of concrete. However, the manufacturing of cement has been proven to have a negative impact on the environment because it contributes to the carbon footprint. The resolution of these environmental issues can be achieved through the implementation of sustainable solutions. This article explores the potential application of coconut shell ash as a substitute for cement in green concrete. Coconut shells (CS) are inevitable by-products derived from the agricultural sector. Coconut shell ash (CSA) was obtained through the combustion of coconut shells. The CSA is substituted by a range of 0 to 20% by weight of cement with a gradual 2.5% increase. The test findings concluded that 12.5% of CSA mix attained the maximum compressive strength. The durability results were found satisfactory in comparison with the normal concrete. The specimens were exposed to different temperatures (i.e., 100 °C, 200 °C, and 300 °C) for a consistent duration of one hour. The CSA concrete exhibited improved residual strength and weight reduction compared to conventional concrete.

Air pollution is a major reason for health-related issues and weather changes, one of humanity's most dangerous problems. It is the most crucial environmental issue in the 21st century and has attracted global attention. These challenges are exacerbated by an overabundance of automobiles, industrial output pollution, transportation fuel consumption, and energy generation. Therefore, air pollution prediction was developed vital. Air pollution monitoring is the procedure of analyzing and measuring the air quality in a certain place to develop the levels of several pollutants and contaminants present. Monitoring air pollution is vital to understand its sources, and effects on the environment and human health, and for executing methods for mitigating its effects. Deep learning (DL) approaches are employed for air pollution predicting methods. Therefore, this study develops an Atomic Orbital Search Algorithm with a Deep Learning-Driven Air Pollution Monitoring (AOSADL-APM) approach. The purpose of the AOSADL-APM technique is to predict and classify the presence of air pollutants. In the presented AOSADL-APM technique, the min-max normalization approach is applied for data pre-processing. For air pollution prediction and classification, the AOSADL-APM technique applies deep long short-term memory (DLSTM) methodology. To enhance the performance of the AOSADL-APM technique, the AOSA-based hyperparameter tuning has been developed. The simulation results of the AOSADL-APM technique were tested using the benchmark dataset. The widespread outcome analyzed the greater solution of the AOSADL-APM algorithm compared to existing approaches.

In this research, we provide a method for synthesizing ZnO nanoparticles using Moringa Oleifera Leaf (M.O Leaf) Extract. UV-VIS Spectroscopy, Scanning Electron Microscopy, EDS, X-ray diffraction and Fourier Transform Infrared Spectroscopy (FTIR) were used to create and characterize ZnO nanoparticles. The spherical size structure of the synthesized nanoparticles with an average grain size of 1 nm was validated by SEM, EXD, and XRD analysis. After the sunlight exposure, the photocatalytic reagent was used to break down the organic dyes in the synthesized ZnO nanoparticles. Nearly 96–97% of the titan yellow and Congo Red dyes were broken down by ZnO nanoparticles.

In this research, a simple method for the preparation of Fe3O4 nanoparticles (Fe3O4NPs) with an average size of 38.05 nm via co-precipitation was investigated. X-ray diffraction (DRX), scanning electron microscopy (SEM), and infrared spectroscopy (FT-IR) were used to characterize obtained Fe3O4 nanoparticles. These Fe3O4NPs were then used as nano-catalysts to degrade Methylene Blue (MB) in an aqueous solution via the Photo Fenton-like process. Also, under room solar light and low temperature, the photocatalytic activity of Fe3O4NPs for degrading MB was optimized through various experimental factors such as pH (ranging from 2 to 8), H2O2 concentration (from 10-2 to 5 × 10-1), catalyst amount (20 to 60 mg), and target organic compound concentrations (10 to 40 mg/L). The optimal experimental conditions were found to be a pH of 3, a dye concentration of 40 mg/L, and 40 mg of Fe3O4NPs as nano-catalyst. These conditions led to a high degree of removal (>86%) of MB dye from water. The pseudo-second-order kinetic model was the suitable model to describe the degradation of MB dye with a coefficient value of 0.969. From this, it was concluded that Fe3O4NPs could act as an effective nano-catalyst for a sustainable and environmentally friendly way to eliminate organic pollutants in water and wastewater. Keywords: Fe3O4Nps, structural characterization, BM degradation, photo-Fenton Oxidation process, pseudo-first-order Model, Nanocatalyst.

This current, comprehensive study of the literature provides a full review of recent developments in a variety of various kinds of solar stills. This review looks at studies on double-slope, hybrid solar stills, single-slope, with a condenser unit, and other particular types of solar stills. To make the work more relevant to readers, the authors provide a thorough summary of the latest research papers in the area of solar stills in addition to a general overview of the many varieties of solar stills. An overview of the various desalination methods is provided in this review paper. Although there have been notable advancements in desalination techniques, the systems' operational costs have remained high throughout time. With the use of cutting-edge technologies, efforts have been made to reduce the price of producing desalinated water. The cost of producing desalinated water is significantly reduced when solar stills are used for desalination. In this review paper that follows, innovative designs and methods for solar still desalination are being used to increase daily productivity while lowering production costs. Numerous changes were tried to extend the residence time and surface area of water that could evaporate, but these changes did not cause the feed water to remain in the still's basin for an extended period.

Biofuels obtained from renewable sources are the only alternative in the global economy from a sustainable point of view. Microalgae have shown tremendous potential as a major source of biomass production that can be used as biofuels. At the same time, gas hydrogen is a non-polluting energy source because it is produced from renewable sources. This study aims to analyze the harvesting efficiency of Dunaliella salina using electrocoagulation with a helix electrode and having HHO gas as hydrogen fuel. D salina harvesting using an EC reactor made of acrylic is done on a batch scale. Helix-shaped type 304 stainless steel is the cathode, and solid cylindrically-shaped Fe is the anode. The voltage set is 20 Volts, while the electrolysis time is varied between 1. 5. 10. 15. 20. 25 and 30 minutes. The harvesting efficiency of D salina using electrocoagulation with a helix electrode was the highest at 84.74%. The highest concentration of dissolved hydrogen gas was 1.753 ppm. The highest volume of HHO gas was 1978 mL resulting from a 30-minute electrocoagulation with a helix electrode, 20-volt voltage. Nanoscale glovaries are formed on the electrode through heterogeneous nucleation at the solid-liquid interface. After nucleation, the nanobubbles grow, and the buoyancy forces of the growing bubbles cause gas release from the cathode surface. This process continues until it causes many bubbles to produce 1978 mL HHO gas for 30 minutes. During the study, the convex HHO gas formed helped remove coagulated D salina floc through electro-flotation. When the time of D salina harvesting using electrocoagulation with a helix electrode significantly affects D salina harvesting efficiency, gas HHO volume, pH, and temperature, harvesting time has no significant effect on dissolved hydrogen gas concentration and ORP.