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The outbreak of severe acute respiratory syndrome coronavirus 2 is regarded as a highly contagious disease that has challenged the healthcare systems worldwide with confirmed cases approaching 12 million and more than 50,000 deaths. Considering the worldwide cases of novel coronavirus disease (COVID-19), it remains a pandemic and the vaccines and therapeutic agents have yet to be developed to stop the spread of this outbreak. Due to the unavailability of specific treatment for the COVID-19, it can be viewed that the risk of cluster infection will continue to be present within the intermittent and small-scale outbreaks. Though the COVID-19 has been identified as a communicable disease, the preventive measures and response policies in South Korea are effectively serving the purpose and gained the confidence to overcome the COVID-19 crisis. This paper includes the exploratory data analysis of COVID-19 cases in South Korea till July 8, 2020. South Korea has reported the lowest death rate with the majority of the deaths, associated with persons with underlying health conditions or elderly infected individuals. Currently the infected patients (total 989) remaining in South Korea are mild cases owing to its robust health care system and quarantine inspection procedures followed by the Ministry of Health and Welfare of South Korea to flatten the COVID-19 curve. Although the COVID-19 countermeasures taken by the South Korean government may not be conclusive or universal for all, but its exemplary approach to tackle COVID-19 can aid countries across the globe to strengthen their response system for the future outbreak of such an infectious disease.
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The outbreak of novel and recent coronavirus disease 2019, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, has made an emergency throughout the world. In India, the outspread of the pandemic was observed on 3 March 2020, and after that exponential growth in the cases was observed in the country. Owing to the widespread transmission, high population density, high testing capacity and ineffective treatment, a continuous rise in cases was observed due to the pandemic in India. In this paper, we have discussed the trend and spread of COVID-19 spread in India with time, history of initial confirmed cases, the impact of phased manner lockdown, age- and gender-wise trend of cases and comparison of cases with the other most affected countries. The study uses exploratory data analysis to describe the current situation of COVID-19 cases in India till 16 August 2020, with the help of data from the Ministry of Health and Family Welfare, Government of India (GOI) and the World Health Organization (WHO). As of August 16, the total number of confirmed cases in India crossed 2.5 million marks with over 50,000 causalities. With more patients recovering and being discharged from hospitals and home isolation (in case of mild and moderate cases), the total recoveries have crossed the 1.8 million mark with a recovery rate of more than 70% and case fatality rate of 1.94% which is maintained below the global average and is on a continuous positive slide. The study also enlightens the preventive and stringent measures taken by India to combat the COVID-19 situation along with the future prospects. The GOI is following its proactive and preemptive approach for management, prevention and containment of COVID-19 in collaboration with the WHO.
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The novel coronavirus (2019-nCoV) originated in China has now covered around 213 countries globally. It has posed health calamities which have threatened the world with the emergence. Owing to the number of confirmed cases still rising every day, it has now become a phase of an international health emergency. Sudden outbreak of coronavirus disease 2019 (COVID-19) has brought global declines in the commodity process. This has majorly affected the demand as well as supply of the commodities. The oil market has been severely affected due to the outrageous collapse in the demand majorly due to travel restrictions which has also caused the steepest decline in oil prices. The prices of both precious and industrial metals have also fallen, although the price drop is less than that of oil prices. The agriculture industry is one of the least affected so far by this pandemic due to its indirect relation with economic activities. However, the ultimate impact of COVID-19 pandemic will greatly depend on the severity and duration of its outspread, but it is expected to have long-lasting implications.
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[This corrects the article DOI: 10.1007/s10668-020-00934-4.].
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Wood preservation has gained global prevalence in recent years, primarily owing to the renewable nature of wood and its capacity to act as a carbon sink. Wood, in its natural form, lacks intrinsic resilience and is prone to decay if left untreated; hence, wood preservatives (WPs) are used to improve wood's longevity. The fate and potential hazards of wood preservatives to human health, ecosystems, and the environment are complex and depend on various aspects, including the type of the preservative compounds, their physicochemical properties, application methods, exposure pathways, environmental conditions, and safety measures and guidelines. The occurrence and distribution of WPs in environmental matrices such as soil and water can result in hazardous pollutants seeping into surface water, groundwater, and soil, posing health hazards, and polluting the environment. Bioremediation is crucial to safeguarding the environment and effectively removing contaminants through hydrolytic and/or photochemical reactions. Phytoremediation, vermicomposting, and sustainable adsorption have demonstrated significant efficacy in the remediation of WPs in the natural environment. Adsorbents derived from biomass waste have been acknowledged for their ability to effectively remove WPs, while also offering cost-efficiency and environmental sustainability. This paper aims to identify wood preservatives' sources and fate in the environment and present a comprehensive overview of the latest advancements in environmentally friendly methods relevant to the removal of the commonly observed contaminants associated with WPs in environmental matrices.
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Ecossistema , Poluentes Ambientais , Humanos , Biodegradação Ambiental , Carvão Mineral , Solo , ÁguaRESUMO
Light-driven photocatalytic (PC) and photoelectrocatalytic (PEC) systems are vital technologies being extensively explored for wastewater treatment and energy production. Although the photo(electro)catalytic applications in both the energy production and wastewater remediation function on the similar principle of photo-induced charge transfer, most preceding research has been focused on either the energy recovery or wastewater treatment as these two applications demand distinct reaction parameters and catalyst properties. The present review reveals the scientific progress in dual-functional PC and PEC processes that enable simultaneous energy recovery (e.g., H2 generation) with wastewater treatment (e.g., degradation of organic pollutants). The key concept in the dual-functional photo(electro)catalytic system is to use both the electron reduction power for recovering H2 from wastewater and hole oxidation power for degrading pollutants in wastewater simultaneously. Herein, a detailed and comprehensive overview of the advancement in various PC and PEC processes with dual-functional purpose is discussed, highlighting the advantages and disadvantages of different systems and performance comparison based on diverse metrics tools. Although in its infancy, this dual-functional technology has gained scientific interest over the past few years; this is expected, as this approach can overcome multiple major environmental challenges, such as water scarcity, global warming, and pollution. The review should offer current limitations and prospects for developing next-generation solar-driven dual-functional techniques based on the water-energy nexus.
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Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Água , Purificação da Água/métodos , CatáliseRESUMO
In this study, novel Cesium (Cs) doped TiO2 nanotubes photoelectrode (Cs/TiO2NTs) were synthesized by simple electrochemical anodization method and characterized by several physicochemical techniques. In particular, the photocatalytic (PC), electrocatalytic (EC) and photoelectrocatalytic (PEC) activity of newly synthesized Cs/TiO2NTs electrodes was investigated using 4-Chloroguaiacol (4-CG). The effect of operating parameters like Cs concentration, electrolyte concentration, external current and pH on degradation efficacy was examined. PEC oxidation using Cs/TiO2NTs lead to 92% degradation of 4-CG in 6â¯h of solar light irradiation under optimized conditions (2.5â¯mM Cs, 160â¯mgâ¯L-1 Na2SO4, 0.03 A current and pH 3). A comparative assessment between PEC, PC and EC process manifested that PEC process was most efficient than the other two processes and Cs/TiO2NTs exhibited higher PEC activity than bare-TiO2 electrodes in terms of degradation and mineralization of organic pollutant. The generation of OH radicals was found to be highest in PEC when compared to EC and PC process. Possible intermediates/byproducts were identified by GC-MS technique and a corresponding tentative degradation pathway has been proposed. Cytotoxicity study showed that PEC has potential to detoxify 4-CG. Hence, combination of TiO2 electrodes decorated with Cs metal can act as a highly efficient photoelectrode for the degradation of hazardous pollutants.
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Césio/química , Técnicas Eletroquímicas/métodos , Guaiacol/análogos & derivados , Nanotubos/química , Titânio/química , Catálise , Eletrodos , Poluentes Ambientais/isolamento & purificação , Guaiacol/isolamento & purificação , OxirreduçãoRESUMO
Gamma radiolytic degradation of an antibiotic, ofloxacin (OFX) was investigated under different experimental conditions. The parameters such as initial OFX concentration, solution pH, absorbed dose and the concentrations of inorganic (CO32-) and organic (t-BuOH) additives were optimized to achieve the efficient degradation of OFX. The degradation dose constant values of OFX were calculated as 2.364, 1.159, 0.776 and 0.618â¯kGy-1 for the initial OFX concentrations of 0.05, 0.1, 0.15 and 0.2â¯mM with their corresponding (G (-OFX)) values of 0.481, 0.684, 1.755 and 1.971, respectively. Degradation rate of OFX was significantly increased with increase in the absorbed dose and decrease in the initial OFX concentration under acidic condition when compared to neutral or alkaline condition. Reaction of OFX in the presence of CO32- and t-BuOH showed that the degradation was primarily caused by the reaction of OFX with radiolytically generated reactive hydroxyl radicals. Mineralization extent of OFX was determined in terms of percentage reduction in total organic carbon (TOC) and results revealed that the addition of H2O2 enhanced the mineralization of OFX from 29% to 36.1% with H2O2 dose of 0.5â¯mMâ¯at an absorbed dose of 3.0â¯kGy. Based on the LC-QTOF-MS analysis, gamma radiolytic degradation intermediates/products of OFX were identified and the possible degradation pathways of OFX were proposed. Cytotoxicity study of the irradiated OFX solutions showed that gamma radiation has potential to detoxify OFX.
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Raios gama , Ofloxacino/efeitos da radiação , Poluentes Químicos da Água/efeitos da radiação , Antibacterianos/efeitos da radiação , Cromatografia Líquida , Peróxido de HidrogênioRESUMO
An efficient gamma radiolytic decomposition of one of the extensively used pharmaceutical ornidazole (ORZ) was explored under different experimental conditions by varying initial concentrations, solution pHs, and doses and concentrations of inorganic ([Formula: see text]) and organic (t-BuOH) additives. The results showed that low ORZ concentrations could be efficiently decomposed using gamma irradiation. The decomposition was followed by pseudo first-order reaction kinetics with rate constant values of 2.34, 1.48, 1.11, and 0.80 kGy-1 for the following initial concentrations: 25, 50, 75, and 100 mg L-1 with their corresponding (G(-ORZ)) values of 1.004, 1.683, 2.237, and 2.273, respectively. Decomposition rate of ORZ was remarkably improved under acidic condition when compared to neutral or alkaline medium. It was also observed that the decomposition was primarily caused by the reaction of ORZ with radiolytically generated reactive HO⢠radicals. The addition of H2O2 had a synergistic effect on the decomposition and mineralization extent of ORZ. However, the removal of total organic carbon (TOC) was not as effective as the decomposition of ORZ. Finally, the quantum chemical calculations were employed to optimize the geometry structure of ORZ and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was used to identify the decomposition intermediates. On the basis of Gaussian calculations and analysis of LC-QTOF-MS, it can be inferred that ORZ radiolytic decomposition was mainly attributed to oxidative HO⢠radicals and the direct cleavage of ORZ molecules. Possible pathways for ORZ decomposition using gamma irradiation in aqueous medium were proposed.
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Antibacterianos/química , Ornidazol/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cromatografia Líquida , Raios gama , Peróxido de Hidrogênio/química , Cinética , Oxirredução/efeitos da radiação , Purificação da Água/instrumentaçãoRESUMO
This paper manifests the potential viability of soil as a cost-free catalyst in photo-Fenton-like processes for treating pharmaceuticals at large scale. Naturally available soil without any cost intensive modification was utilized as a catalyst to degrade pharmaceuticals, specifically ornidazole (ORZ) and ofloxacin (OFX). Soil was characterized and found enriched with various iron oxides like hematite, magnetite, goethite, pyrite and wustite, which contributes toward enhanced dissolution of Fe3+ than Fe2+ in the aqueous solution resulting in augmented rate of photo-Fenton reaction. The leached iron concentration in solution was detected during the course of experiments. The degradation of ORZ and OFX was assessed in solar induced batch experiments using H2O2 as oxidant and 95% ORZ and 92% OFX removal was achieved. Elevated efficiencies were achieved due to Fe2+/Fe3+ cycling, producing more hydroxyl radical leading to the existence of homogeneous and heterogeneous reactions simultaneously. The removal efficiency of solar photo-Fenton like process was also compared to photo-Fenton process with different irradiation sources (UV-A and UV-B) and were statistically analysed. Continuous-scale studies were conducted employing soil either in the form of soil beads or as a thin layer spread on the surface of baffled reactor. Soil beads were found to have satisfactory reusability and stability. 84 and 79% degradation of ORZ and OFX was achieved using soil as thin layer while with soil beads 71 and 68% degradation, respectively. HPLC and TOC study confirmed the efficient removal of both the compounds. Toxicity assessment demonstrates the inexistence of toxic intermediates during the reaction.