High concentration of surface ozone (O3) will cause health risks to people. In order to analyze the spatiotemporal characteristics of O3 and assess O3 exposure and health risks for different age groups in China, we applied multiple methods including standard deviation ellipse, spatial autocorrelation, and exposure–response functions. Results show that O3 concentrations increased in 64.5% of areas in China from 2013 to 2018. The central plain urban agglomeration (CPU), Beijing-Tianjin-Hebei (BTH), and Yangtze River Delta (YRD) witnessed the greatest incremental rates of O3 by 16.7%, 14.3%, and 13.1%. Spatially, the trend of O3 shows a significant positive autocorrelation, and high trend values primarily in central and east China. The proportion of the total population exposed to high O3 (above 160 μg/m3) increased annually. Compared to 2013, the proportion of the young, adult, and old populations exposed to high O3 increased to different extents in 2018 by 26.8%, 29.6%, and 27.2%, respectively. The extent of population exposure risk areas in China expanded in size, particularly in north and east China. The total premature respiratory mortalities attributable to long-term O3 exposure in six urban agglomerations were about 177,000 in 2018 which has increased by 16.4% compared to that in 2013. Among different age groups, old people are more vulnerable to O3 pollution, so we need to strengthen their relevant health protection of them.

In this study, waste tires were used to develop activated carbon for the adsorption of Cr(VI) from aqueous solutions, and an artificial neural network (ANN) model was applied to predict the adsorption efficiency of waste-tire activated carbon (WTAC). SEM and FTIR were used to characterize the developed WTAC. A three-layer ANN with different training algorithms and hidden layers with different numbers of neurons was developed using 79 data sets gathered from batch adsorption experiments with different initial Cr(VI) ion concentrations, contact periods, temperatures, and doses. Conjugate gradient backpropagation of Powell-Beale restarts (traincgb) was found to be the best training algorithm among all the training algorithms, with an RMSE of 5.894 and an R2 of 0.985. The ANN topology had 4, 8, and 4 neurons in the input, hidden, and output layers. The correlation coefficient of the ANN models of Cr(VI) ion adsorption efficiency is 0.977.

The River Chief System is an administrative model of water environment governance currently adopted in China. Under this system, the chief CPC and government leaders at various levels serve as “river chiefs” and are responsible for organizing and directing the management and protection of the rivers and lakes within their remit. This paper tries to reveal the actual effectiveness of the River Chief System based on the behaviors of grassroots river chiefs (GRCs). First-hand data about GRCs is obtained through a questionnaire survey. Whether the water environment governance target is achieved and the water quality change of the river sections in the charge of GRCs is quantitatively assessed It has been found that, except for implementing “one policy for one river” and making river patrols, the behaviors of GRCs have no positive effect on river pollution prevention and control, implying the ineffectiveness of the River Chief System. The framework design of the River Chief System should be optimized, and a system with professionals to support GRCs in performing their duties should be established. Moreover, the tendency to use environmental regulation as a mandatory policy tool should be weakened. These measures are of great practical significance to the implementation of the green development concept and the furthering of the River Chief System overall.

The present investigation aims to evaluate the feasibility of using Persea americana (Avocado) biodiesel in compression ignition engines. Persea americana bio-oil was extracted through a soxhlet extraction process using n-hexane solvent after careful pre-processing of the feedstocks. Since the Free Fatty Acid content was 1.78% estimated through titration, single stage base-catalyzed transesterification technique was adopted using methanol and sodium hydroxide as catalysts in the molar ratio of 1:6. Gas Chromatography-Mass Spectrometry analysis revealed the presence of Oleic acid in major proportions. The Fourier transform Infra-Red analysis confirmed the presence of carbonyl group ester ions between 722.19 cm-1 and 1460 cm-1. The 13C NMR and 1H NMR studies supported the successful transformation of triglycerides into Fatty Acid Methyl Esters with distinct peaks at 3.369 ppm and 48.147 ppm, respectively.

To overcome the challenges of the increasing global energy and to solve the global energy & environment problems, process intensification is one way to develop new efficient production pathways for the chemical industry. Process intensification plays an important role in the gas-liquid mass transfer processes. This review provides an overview of the developments in gas-liquid mass transfer enhancement. A major enhancement method, namely introducing additives (including nanoparticles, oil, electrolyte, and surfactant) summarized and discussed here, includes the most recent accomplishments in gas-liquid mass transfer engineering. This review is expected to inspire new research for future developments and potential applications in scientific research and industry regarding gas-liquid mass transfer engineering. Finally, it presents conclusions and perspectives on enhancing gas-liquid mass transfer.

Pollutants like arsenic, chromium, or other toxic heavy metals have the most dreadful impact on humans or animals and also become a threat worldwide. Introducing these contaminants into the environment is not just due to the chemical industry but also coexists in combined form in underground rocks, contaminating groundwater during breakdown. Epidemics are now largely blamed on toxic pollution in many different nations worldwide. The issue has gotten worse in underdeveloped nations, where metal contamination of the groundwater affects more than a million people. Different techniques are used to remove toxic pollutants from water, but most are expensive and energy intensive. Adsorption is preferable for removing contaminants such as heavy metals or chemical dyes. As nanomaterials have been demonstrated to be more effective as nanocomposites, we used an adsorbent of nanomaterial to use the adsorption approach. These materials have become more well-liked because of their useful applications and improved characteristics. Magnetic synthesized nanocomposites have magnetic properties, which become beneficial for adsorption as it enhances adsorption capacity. The insertion of the plant or aggregate waste material for nanocomposite synthesis inhibits the growth of bacteria or other microorganisms, preventing the material from getting infected if it is in the environment. In this review paper, we have focused on the green synthesis of nanomaterials used for water treatment.

The paper investigated the adsorption of Cr(VI) on biochar in simulated wastewater by static adsorption method, Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) characterization analysis. The results show that biochar can effectively remove Cr(VI) in wastewater, and the adsorption equilibrium can be quickly reached within 100 min. The kinetic analysis shows that the quasi-second-order kinetic model can better fit the kinetic process of Cr(VI) adsorption by biochar, which shows that the main mechanism of the adsorption is the chemical bonding cooperation between Cr(VI) and the functional groups on the surface of biochar. Fit analysis of the isotherm at different temperatures shows that temperature increase promotes the adsorption of Cr(VI) on biochar, and thermodynamic analysis reveals that the adsorption of Cr(VI) on biochar is a spontaneous endothermic process. The Freundlich model effectively fits the adsorption isotherm of Cr(VI), indicating that the surface of biochar is uneven and Cr(VI) has undergone multilayer adsorption. The adsorption isotherm of Cr(VI) under the influence of HA and FA can be effectively fitted by the Freundlich model, and the adsorption efficiency is the highest when FA is added. The national analysis of Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) further reveals the bond cooperation between Cr(VI) and the surface functional groups of biochar. The results show that biochar has potential application value in treating chrome-containing wastewater.

Nanoparticles are an important tool for new updations and advancements in diverse sectors. The inorganic metal and metal oxide nanoparticles have enormous research interest because of their great relevance in medicine, wastewater treatment, catalysis, biotechnology, and in the formation of energy storage devices. The NiO NPs can be synthesized using different physical and chemical methods and exploring all their possible applications. Green synthesis is the easy, safe, and effective nanoparticle synthesis route. Green metal and metal oxide nanoparticle syntheses provide the most affordable, convenient, and biocompatible approach for fabricating NiO NPs. This way is a good alternative to the conventional methods of synthesis. Green synthesis, being more constructive, is widely used in research and gives promising outcomes. This review highlighted the unique feature of the NiO nanoparticles. This paper brings forth the usage of green synthesis for synthesizing NiO nanoparticles. It also provides readers with a collective review of the recent development in the green synthesis of NiO NPs and their potential application in different fields.

The study aims to understand employees’ knowledge, awareness, and overall perception of drinking water quality in the Iron and Steel Industry in Burnpur, India. Further, this study evaluated drinking water’s physicochemical and bacteriological properties collected from different company sites. This study uses a mixed-method approach with individual interviews of selected employees (n=342) and the laboratory test of eight selected drinking water sites. The results show that most employees considered drinking water acceptable to be excellent. However, only 30% of employees in Site 1 (Coke Oven By-Product department) have reported organoleptic properties of water under the excellent category. The result explained that other physicochemical and bacteriological properties are in good status in all sites except for a colony count, expressing their suitability for drinking purposes. In summary, employees’ perception of water quality aligns with their drinking water’s physicochemical and bacteriological properties.

Nickel laterite mining is one of the sources of nickel-iron material used for producing steel and various materials. This mining activity leaves waste in the mine, including rocks, overburden, silt, and dust. Characterization is an important primary step in understanding waste for proper management, utilization, and disposal. The pH, organic matter, and elemental composition are analyzed in this study. The pH of nickel laterite mine waste is neutral to moderately alkaline, which makes it unlikely to cause acid mine drainage, which is one of the most prevailing environmental problems of mines. The organic matter content also showed favorable results for plant growth. However, the macronutrients necessary for the plant are too high, making it less favorable for agricultural utilization. Elemental composition shows the presence of nickel and other elements lower than the economically acceptable level. However, processing the lower grade can be the best option when all higher-grade resources are exhausted. The nickel laterite mine waste can be reused to further extract the metals when sources of higher grades are depleted, repurposed such as in the production of bricks and ceramics, or mined-out mines can be repurposed for renewable energy sources such as solar and wind farms.