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A Brief Review of Detection and Removal of Bisphenol A in Aqueous Media 全文
2022
dos Santos Costa, Maria Joseíta | Araújo, João Victor Silva | Moura, Jéssika Kaline Lopes | da Silva Moreno, Luís Henrique | Pereira, Palloma Assunção | da Silva Santos, Reginaldo | Moura, Carla Veronica Rodarte
Bisphenol A (BPA) is a synthetic monomer applied in the polymeric industry that can contaminate food and water, leading to serious health risks associated with human exposure. The consumption of food and water contaminated with this compound directly affects the endocrine system and increases the susceptibility to cancer. The purpose of this review is to present the main studies dedicated to detection and removal of BPA from aqueous media. The literature reports different ways of detecting BPA in different fluids, such as aqueous solutions, water matrix, and bottled drinks (water, juices, and soft drinks). In addition, the main treatment of these matrixes include adsorption or (photo)degradation processes. Detection techniques include high-performance liquid chromatography (HPLC), gas chromatography (GC), capillary electrophoresis (EC), immunochromatographic assay, and electrochemical sensors. The recent studies discourse about BPA removal includes techniques such as (photo)degradation Fenton, adsorption, peroxidation, oxidation and heterogeneous photocatalysis. For photo-degradation, many semiconductor oxides have been used, which can be active under visible or ultraviolet irradiation. Also, plant-based materials have been used as adsorbate to remove BPA. In general, all available techniques present advantages and disadvantages for determining and removing BPA in aqueous media. In this review, we will discuss the main contributions of recent studies related to the detection and treatment of systems contaminated with BPA.
显示更多 [+] 显示较少 [-]An investigation of alkali-activated slag pastes containing recycled glass powder under the effect of elevated temperatures 全文
2022
Rashad, Alaa M. | Essa, Ghada M. F. | Abdel-Gawwad, Hamdy A.
Herein, the possibility of including recycled glass powder as a promising material in amalgamation with slag to produce new binder materials activated by sodium silicate solution capable to resist high temperatures was studied. Slag was partially replaced with glass powder (GP) at ratios in the range of 0–15%, by weight, with a step of 5%. The powders were activated by a constant concentration of sodium silicate solution. The percentage of water absorption and compressive strength were monitored at the ages of 3, 7 and 28 days. After 28 curing days, the specimens were subjected to severe temperatures in the range of 400–1000 °C with a step of 200 °C for 2 h and the residual compressive strength was monitored. The results were analysed by X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectra. The results revealed higher water absorption and lower compressive strength with the incorporation of GP. The incorporation of GP has a negative effect on the compressive strength of alkali-activated slag (AAS) pastes after exposure to 400 and 600 °C, whilst it has a positive effect after exposure to 800 and 1000 °C.
显示更多 [+] 显示较少 [-]The Mediterranean limpet Patella caerulea (Gastropoda, Mollusca) to assess marine ecotoxicological risk: a case study of Tunisian coasts contaminated by metals 全文
2022
Zaidi, Mariem | Athmouni, Khaled | Metais, Isabelle | Ayadi, Habib | Leignel, Vincent
Participants in the coastal socio-economy of the Mediterranean Sea, such as industries, aquaculture, urban populations, conglomerates, and tourists, create intense anthropogenic pressures on marine ecosystems (such as the release of trace metals). This raises concerns about their impact on the surrounding environment and on marine organisms, including those collected for human consumption. This study introduces the possibility of using Patella caerulea (Linnaeus 1758), indigenous to the Mediterranean Sea, as a biosentinel of marine pollution. This study proposes coupling environmental (bioaccumulation) and toxicological (redox homeostasis) measures of bioavailability with genetic variability (COI mtDNA) assessments. Concentrations of six trace metals (cadmium, copper, iron, lead, nickel, and zinc) were measured in surface seawater and in P. caerulea individuals collected from four coastal stations on the Tunisian coast where different levels of metal contamination have occurred. The quantified biomarkers involved the determination of antioxidant defense enzymes, catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), and the measurement of lipid peroxidation indicated by malondialdehyde (MDA) levels. Our study identified critical levels of metal contamination among locations in the Gulf of Gabes. Concomitantly, the induction of antioxidant biomarkers (especially SOD and GPX) was observed, highlighting the potential of P. caerulea to acclimate to stressful pollution conditions. Molecular analysis of COI (mtDNA) revealed low discrimination between the four P. caerulea populations, highlighting the role of marine currents in the Mediterranean Sea in the dispersal and passive transportation of limpet larvae, allowing an exchange of individuals among physically separated, P. caerulea populations.
显示更多 [+] 显示较少 [-]Preparation of photoluminescent and anticorrosive epoxy paints immobilized with nanoscale graphene from sugarcane bagasse agricultural waste 全文
2022
Al-nami, Samar Y. | Al-Qahtani, Salhah D. | Snari, Razan M. | Ibarhiam, Saham F. | Alfi, Alia Abdulaziz | Aldawsari, Afrah M. | El-Metwaly, Nashwa M.
Sugarcane bagasse agricultural waste has been one of the most common solid pollutants worldwide. Thus, introducing a simple method to convert sugarcane bagasse into value-added materials has been highly significant. Herein, we develop a simple and green strategy to reprocess sugarcane bagasse as a starting material for the preparation of graphene oxide nanosheets toward the preparation of novel photoluminescent, hydrophobic, and anticorrosive epoxy nanocomposite coatings integrated with lanthanide-doped aluminate nanoparticles. Environmentally friendly graphene oxide (GO) nanostructures were provided by a single-step preparation procedure from sugarcane bagasse (SCB) agricultural waste using ferrocene-based oxidation under muffled conditions. The oxidized SCB nanostructures were applied as a drier, anticorrosion, and crosslinking agent for epoxy coatings. Different concentrations of pigment phosphor were applied onto the epoxy coating. The generated epoxy-graphene-aluminate (EGA) paints were then coated onto mild steel. The hydrophobic properties and hardness as well as resistance to scratch of the EGA paints were examined. The transparency and colorimetric screening of the EGA nanocomposite paints were determined by the absorption spectral analysis and CIE Lab parameters. The luminescent translucent paints demonstrated a bright green emission at 520 nm when excited at 372 nm. The anticorrosion properties of the painted steel submerged in NaCl₍ₐq₎ were inspected by the electrochemical impedance spectral (EIS) method. The EGA paints with phosphor (11% w/w) exhibited the most distinct anti-corrosion properties and long-persistent luminescence. The produced paints displayed high durability and photostability.
显示更多 [+] 显示较少 [-]A comparison of the effect of diurnal temperature range and apparent temperature on cardiovascular disease among farmers in Qingyang, Northwest China 全文
2022
Zhai, Guangyu | Qi, Jintao | Zhang, Xuemei | Zhou, Wenjuan | Wang, Jiancheng
Climate change is increasing the incidence of extreme weather events which have a significant impact on public health. Cardiovascular diseases (CVDs) are the number one cause of death globally (40%). Apparent temperature (AT) and diurnal temperature range (DTR) have been extensively used to evaluate the effects of temperature on cardiovascular disease (CVD). However, the relevant information is quite limited from analysis and comparison of effects and differing pathogenesis of DTR and AT on CVD especially in less-developed, rural areas of China. This is the first attempt to analyze different effects between AT and DTR on CVD using distributed lag nonlinear modeling (DLNM) in rural area. Data on CVD hospital admission in Qingyang (Northwest China) in 2014–2017 originated from the New Rural Cooperative Medical System (NRCMS) of Gansu Province, and meteorological variables were provided by the Meteorological Science Data Sharing Service. Both AT and DTR had significant nonlinear and delayed impacts on hospital admissions for CVD. DTR had a stronger and more persistent effect on CVD incidence than AT. Females were more affected by high AT and low DTR than were males, while males were more vulnerable to low AT and high DTR. Temperature effects were not significantly different between people above and below 65 years of age. These findings provide local public health authorities with reference concerning sensitive temperature indices for susceptible populations with a view to improve CVD preventive strategies in rural areas.
显示更多 [+] 显示较少 [-]Pathways of soil N2O uptake, consumption, and its driving factors: a review 全文
2022
Liu, Hongshan | Li, Yuefen | Pan, Baobao | Zheng, Xiangzhou | Yu, Juhua | Ding, Hong | Zhang, Yushu
Nitrous oxide (N₂O) is an important greenhouse gas that plays a significant role in atmospheric photochemical reactions and contributes to stratospheric ozone depletion. Soils are the main sources of N₂O emissions. In recent years, it has been demonstrated that soil is not only a source but also a sink of N₂O uptake and consumption. N₂O emissions at the soil surface are the result of gross N₂O production, uptake, and consumption, which are co-occurring processes. Soil N₂O uptake and consumption are complex biological processes, and their mechanisms are still worth an in-depth systematic study. This paper aimed to systematically address the current research progress on soil N₂O uptake and consumption. Based on a bibliometric perspective, this study has highlighted the pathways of soil N₂O uptake and consumption and their driving factors and measurement techniques. This systematic review of N₂O uptake and consumption will help to further understand N transformations and soil N₂O emissions.
显示更多 [+] 显示较少 [-]Nanomaterials photocatalytic activities for waste water treatment: a review 全文
2022
Singh, Permender | Mohan, Brij | Madaan, Vasundhara | Ranga, Rohit | Kumari, Parveen | Kumar, Sandeep | Bhankar, Vinita | Parmod Kumar, | Kumar, Krishan
Water is necessary for the survival of life on Earth. A wide range of pollutants has contaminated water resources in the last few decades. The presence of contaminants incredibly different dyes in waste, potable, and surface water is hazardous to environmental and human health. Different types of dyes are the principal contaminants in water that need sudden attention because of their widespread domestic and industrial use. The toxic effects of these dyes and their ability to resist traditional water treatment procedures have inspired the researcher to develop an eco-friendly method that could effectively and efficiently degrade these toxic contaminants. Here, in this review, we explored the effective and economical methods of metal-based nanomaterials photocatalytic degradation for successfully removing dyes from wastewater. This study provides a tool for protecting the environment and human health. In addition, the insights into the transformation of solar energy for photocatalytic reduction of toxic metal ions and photocatalytic degradation of dyes contaminated wastewater will open a gate for water treatment research. The mechanism of photocatalytic degradation and the parameters that affect the photocatalytic activities of various photocatalysts have also been reported.
显示更多 [+] 显示较少 [-]Pollution assessment and mapping of potentially toxic elements (PTE) distribution in urban wastewater fed natural wetland, Kolkata, India 全文
2022
Bera, Tanushree | Kumar, Vikash | Sarkar, Dhruba Jyoti | Devi, Manoharmayum Shaya | Behera, Bijay Kumar | Das, Basantakumar
East Kolkata Wetland (EKW) is one of the largest sewage-fed wetlands in the world, which support the livelihood of thousands of peoples. However, at present, EKW system has become ecologically vulnerable due to the discharge of toxic waste through the sewage canal from the Kolkata metropolitan city. Hence, it becomes very important to understand the inflow and load of potentially toxic elements (PTE) in the sediment, water, and fish of sewage-fed wetland used for aquaculture activities. In this study, one of the polluted wetland from EKW, Sardar bherry, was selected as the study area. Sediment samples (45) were collected from 15 sites to characterize the PTEs concentrations levels utilizing inductively coupled plasma mass spectrometry, and their spatial distribution pattern and pollution quality indices were estimated. Water (45) and fish (7) samples were also analyzed to understand the distribution pattern of PTEs from sediment to water and water to fish. The geostatistical prediction map showed that the concentration range of Cr, Fe, Cu, Co, Zn, Cd, Ni, Pb, and Mn in sampling stations were 27.3–84.1 μg g⁻¹, 7281–30193 μg g⁻¹, 50.6–229.7 μg g⁻¹, 4.8–15.3 μg g⁻¹, 113.4–776.9 μg g⁻¹, 10.0-26.9 μg g⁻¹, 23.8–55.7 μg g⁻¹, 9.5–39.3 μg g⁻¹, and 188.6–448.5 μg g⁻¹ respectively. Pollution is alarming in sediment as all of the studied PTEs exceed the threshold effect level according to Sediment Quality Guidelines. Cd levels in sediments were found to be upper than the lowest effect level (LEL), probable effect level (PEL), threshold effect level (TEL), and severe effect level (SEL) for all sample locations. Several pollution assessment indexes (contamination factor, geo-accumulation index, ecological risk index, etc.) also showed that sediment samples were severely polluted by Cd. PTEs status in water and fish is within permissible limits. The study emphasizes that attention should be paid to controlling the excessive accumulation of PTEs in sediment that would further harm the ecological environment and ultimately human health.
显示更多 [+] 显示较少 [-]Globalization toward environmental sustainability and electricity consumption to environmental degradation: does EKC inverted U-shaped hypothesis exist between squared economic growth and CO2 emissions in top globalized economies 全文
2022
Weimin, Zhu | Sibt-e-Ali, Muhammad | T̤āriq, Muḥammad | Dagar, Vishal | Khan, Muhammad Kamran
The study inspects the inverted U shape of the environmental Kuznets curve (EKC) hypothesis following the influence of economic growth on CO₂ emissions and the reaction of electricity consumption and globalization toward CO₂ emissions in top globalized economies. This study has taken the data of the top 9 globalized countries from 1990 to 2019 while adopting fully modified ordinary least squares and dynamic ordinary least squares panel cointegration approaches to determine the long run effects and Dumitrescu and Hurlin panel causality for the directions of the causality among the variables. According to the long-term findings of the research, economic growth and electricity consumption substantially contribute to CO₂ secretions. On the other hand, the squared growth and globalization mitigate CO₂ emissions and contribute to environmental sustainability. However, the inverse influence of squared growth on CO₂ emissions shows the presence of the inverted U shape of the EKC hypothesis. Furthermore, Dumitrescu and Hurlin causality measures have shown the bi-directional causality of electricity consumption and economic growth with CO₂ emissions and globalization with economic growth. At the same time, unidirectional causality exists from globalization to CO₂ emissions, economic growth to electricity consumption, and electricity consumption to globalization. The study recommends long-term globalization and sustainable development projects to ensure environmental sustainability in these globalized economies.
显示更多 [+] 显示较少 [-]Fullerenes for the treatment of cancer: an emerging tool 全文
2022
Fernandes, Neha Benedicta | Shenoy, Raghavendra Udaya Kumar | Kajampady, Mandira Kashi | DCruz, Cleona E. M. | Shirodkar, Rupesh K. | Kumar, Lalit | Verma, Ruchi
Cancer is a most common cause of mortality globally. Available medicines possess severe side effects owing to their non-specific targeting. Hence, there is a need of an alternative in the healthcare system that should have high efficacy with the least side effects, also having the ability to achieve site-specific targeting and be reproducible. This is possible with the help of fullerenes. Fullerenes are having the unique physicochemical and photosensitizer properties. This article discusses the synthesis, functionalization, mechanism, various properties, and applications of C60 fullerenes in the treatment of cancer. The review article also addresses the various factors influencing the activity of fullerenes including the environmental conditions, toxicity profile, and future prospective.
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