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Systematic review and meta-analysis on the association between seasonal variation and gestational diabetes mellitus Полный текст
2021
Khoshhali, Mehri | Ebrahimpour, Karim | Shoshtari-Yeganeh, Bahareh | Kelishadi, Roya
Recently, there is growing evidence that ambient temperature and seasonal changes are related to the incidence of gestational diabetes mellitus (GDM). Thereby, this study was conducted to evaluate the association between seasonal changes and ambient temperature and GDM. We conducted a systematic search in PubMed, ISI Web of Science, Scopus, Google Scholar, and Cochrane Collaboration for human studies available until the end of 2020. We used the following keywords to identify relevant articles: “Diabetes, Gestational” (MeSH), “Glucose Tolerance Test” (MeSH), “Glucose intolerance” (MeSH), “Pregnancy outcome” (MeSH), “Birth outcome”, “Seasons” (MeSH), “Weather” (MeSH), “Ambient Temperature,” “Climate Change” (MeSH). Meta-analyses by using STATA software were conducted for analyzing data. Due to the high heterogeneity between included studies, a random-effects model was used. Subgroup analysis, meta-regression, and sensitivity analysis were used to define a source of heterogeneity. We found 13 studies related to the association between ambient temperature and season changes and GDM, which 11 of them were included in meta-analyses. Despite inconsistencies in outcome assessment across studies, we found a significant positive association between seasons of GDM screening and risk of GDM (pooled OR=1.12; 95% CI (1.03, 1.21)). The funnel plot and Egger’s test showed that there was no significant publication bias among these studies (p=0.51). In general, season changes showed a significant positive relationship with prevalence of GDM. However, due to the unknown exact mechanism on this association, further studies should be conducted.
Показать больше [+] Меньше [-]Highly stable halide perovskite with Na incorporation for efficient photocatalytic degradation of organic dyes in water solution Полный текст
2021
Sun, Jifu | Yang, Zhijuan | Li, Longzhi | Zhang, Yue | Zou, Guifu
To overcome water instability and low photocatalytic activity of lead-free halide perovskite for the degradation of organic dyes, we report a novel photocatalyst of lead-free halide perovskite with Na incorporation and employ it for the photocatalytic degradation of organic dyes in water solution under visible light irradiation. The main purpose of this work is to confirm the feasibility of lead-free halide perovskite with Na incorporation for improving the photocatalytic efficiency and recyclability in water solution and further to explore the mechanism behind the enhancement of photocatalytic performance after Na incorporation. The results show that Cs₂Ag₀.₆₀Na₀.₄₀InCl₆ can increase the dye degradation rate by at least 50% than the lead-free halide perovskite (Cs₂AgInCl₆) and the photocatalyst of Ag substituted by Na (Cs₂NaInCl₆). The degradation efficiency of rhodamine 6G catalyzed by Cs₂Ag₀.₆₀Na₀.₄₀InCl₆ reaches 94.94% over 60 min, which is 72% higher than that catalyzed by Cs₂NaInCl₆ and 27% higher than that catalyzed by Cs₂AgInCl₆. What’s more, the degradation efficiency of methyl orange catalyzed by Cs₂Ag₀.₆₀Na₀.₄₀InCl₆ is 90.39% within 150 min, which is 66% higher than that catalyzed by Cs₂NaInCl₆ and 54% higher than that catalyzed by Cs₂AgInCl₆. Moreover, the photocatalyst of Cs₂Ag₀.₆₀Na₀.₄₀InCl₆ exhibits a desirable recyclability by water exposure, retaining the degradation efficiency over 90% after five cycles. The strengthened photocatalytic performance in the presence of Cs₂Ag₀.₆₀Na₀.₄₀InCl₆ is ascribed to an increase of radiative recombination rate and an improvement of average lifetime to 204 ns since an appropriate Na incorporation at the atomic ratio of Na/Ag=4:6 breaks the original crystal lattice and meanwhile increases the electron and hole overlap. The work proves a great potential of halide perovskite with Na incorporation for the highly efficient photocatalytic degradation of organic dyes in water solution.
Показать больше [+] Меньше [-]Assessment of confined aquifer response to recharge variations and water inflow distributions using analytical approach Полный текст
2021
Zarif Sanayei, Hamed Reza | Javdanian, Hamed | Rakhshandehroo, Gholam Reza
Quantification of the amount of the exchanged water between the surface water and a confined aquifer is a basic step in water balance and environmental hydraulics. The hydraulic connection between a surface water and a confined aquifer may occur through different recharge variations. The current research presents new analytical solutions for confined aquifer response to recharge variations and different inflow distributions. Different cases were studied, where a constant piezometric head is applied at the right boundary of the 2D confined aquifer plane and various distributions of water inflow through the recharging windows are considered on a part and/or parts of the left boundary. Finally, a uniform water inflow distribution on parts of the left boundary and a uniform distribution of water outflow at the right boundary was considered. Both steady and unsteady state problems can be solved using proposed equations. The performance of developed analytical solutions was examined compared to the numerical finite difference modeling. The results show reasonable precision of the developed analytical solutions. The developed solutions can be used as a benchmark to verify numerical approaches with similar boundary conditions.
Показать больше [+] Меньше [-]Preparation of Ce0.9Zr0.1O2/SnIn4S8 composite photocatalyst and its degradation of typical antibiotic pollutants Полный текст
2021
Lv, Yuancai | Yu, Jianying | Huang, Siyi | Zheng, Kaiyun | Yang, Guifang | Liu, Yifan | Lin, Chunxiang | Ye, Xiaoxia | Liu, Minghua
Considering the high environmental risk, the remediation of antibiotic pollutants attracted numerous attentions. In this work, a novel photocatalyst, Ce₀.₉Zr₀.₁O₂/SnIn₄S₈, was fabricated by in situ precipitation and hydrothermal method and then applied to the degradation of norfloxacin under the irritation of visible light. The SEM, TEM, XRD, XPS, and electrochemical results clearly showed that the n-type heterojunction between Ce₀.₉Zr₀.₁O₂ and SnIn₄S₈ was successfully constructed, which greatly reduces the recombination of the photogenic electron and holes, leading to the improvement of photocatalytic performance and stability (recycled over eight times). Besides, the Ce₀.₉Zr₀.₁O₂/SnIn₄S₈ composite also exhibited good ability to mineralize norfloxacin. Under the optimal condition (pH 3, 1 g L⁻¹ of 10% Ce₀.₉Zr₀.₁O₂/SnIn₄S₈, and 8 mg L⁻¹ of initial norfloxacin concentration), norfloxacin could be fully and rapidly degraded in 60 min, and completely mineralized in 4 h (99.3 ± 1.7%). LC-QTOF-MS results evidently displayed eight intermediates during norfloxacin degradation. In addition, with the attack of the reactive oxygen species (h⁺, •OH, and •O₂⁻), norfloxacin could be effectively decomposed via deoxygenation, hydroxylation, and carboxylation reactions. Notably, compared to photodegradation, the photocatalytic process could completely eliminate the norfloxacin from water because it could avoid the accumulation of toxic byproducts.
Показать больше [+] Меньше [-]Deterministic risk assessment of firefighting water additives to terrestrial organisms Полный текст
2021
Graetz, Sarah | Martin, William | Washuck, Nicole | Anderson, Jenna | Sibley, Paul K. | Prosser, Ryan S.
Firefighting water additives are used to increase the rate at which fires can be extinguished. The majority of ecotoxicological research has focused on firefighting formulations containing perfluorinated compounds as additives, due to the persistence and bioaccumulative nature of the perfluorinated constituents. A number of relatively new additives have come on the market to replace the products containing perfluorinated compounds. The potential effect of these new additives on the environment has been largely unstudied. This study investigated the toxicity of six firefighting water additives: Eco-Gel™, ThermoGel 200L™, FireAde™, Fire-Brake™, Novacool Foam™, and F-500™ to terrestrial biota. Terrestrial organisms could be exposed to firefighting water additives through leaching into soil and/or runoff following a firefighting event or through direct aerial application during a forest fire. Toxicity to three plant species was assessed through seedling germination and emergence tests: Fagopyrum esculentum (buckwheat), Raphanus raphanistrum subsp. sativus (radish), and Rudbeckia hirta (black-eyed Susan). The effects of firefighting water additives on three soil invertebrates, the collembolan Folsomia candida, the earthworms Eisenia andrei, and Dendrodrilus rubidus, were also investigated using static acute tests to estimate EC₅₀/LC₅₀s. The concentration that resulted in a 50% reduction in survival (LC₅₀) for the acute toxicity tests conducted with F. candida ranged from 3 (Eco-Gel) to 0.175% (Novacool) by volume. Comparatively, the acute toxicity of two firefighting water additives to D. rubidus could not be determined, as a 50% reduction in survival was not observed. A number of firefighting water additives were found to pose a hazard to terrestrial organisms based on a worst-case exposure scenario of direct application at the greatest recommended application rate for a class A fire (e.g., wood, paper). The firefighting water additive F-500 was found to pose a hazard (HQ ≥ 1) for all species tested, except for the acute test conducted with D. rubidus. Comparatively, Eco-Gel posed a hazard for only the acute and chronic tests with F. candida. This study represents the first comparative deterministic risk assessment of firefighting water additives to terrestrial ecosystems.
Показать больше [+] Меньше [-]Does tradeoff between financial and social indicators matters in environmental consideration: evidence from G7 region Полный текст
2021
Van Song, Nguyen | Phuong, Nguyen Thi Minh | Oanh, Thai Thi Kim | Chien, Do Huy | Phuc, Vu Quang | Mohsin, Muhammad
The study tries to discover the impact of financial and social indicators’ growth towards environmental considerations to understand the drivers of economic growth and carbon dioxide emissions change in G7 countries. The DEA-like composite index has been used to examine the tradeoff between financial and social indicator matters in environmental consideration by using a multi-objective goal programming approach. The data from 2008 to 2018 is collected from G-7 countries. The results from the DEA-like composite index reveals that there is a mixed condition of environmental sustainability in G-7 countries where the USA is performing better and Japan is performing worse among the set of other countries. The further result shows that the energy and fiscal indicators help to decrease the dangerous gas emissions. Divergent to that, the human and financial index positively contributes to greenhouse gas emissions. Fostering sustainable development is essential to successfully reduce emissions, meet established objectives, and ensure steady development. The study provides valuable information for policymakers.
Показать больше [+] Меньше [-]A comprehensive study on amalgamation of sustainable solar powered distillation for arsenic and fluoride removal from groundwater Полный текст
2021
Kapadia, Yash | Mehta, Avish | Shah, Vraj | Kotadia, Deep | Shah, Sanskar | Shah, Manan
Due to the growing population and rapid urbanization, fresh water is becoming increasingly scarce. Apart from drinking, clean water is essential in a variety of applications such as batteries, pharmaceuticals, vehicles, and many research and development labs. Due to the unfeasible deficiency of the groundwater reserves, we must understand the importance of judicious usage and proper supervision of the groundwater resources. For the removal of various harmful substances in the groundwater such as arsenic, fluorides, and chlorides, we take the help of groundwater distillation. With the increase in environmental pollutions caused due to the use of injudicious usage of natural resources, we should look for an alternative for groundwater distillation techniques using renewable energy such as solar power. Groundwater is widely acknowledged as a major supply of water for drinking, agriculture, and a variety of other uses. Researchers have also employed solar distillation to transform groundwater into drinkable water. Hence, the main aim of the review paper is that we use solar power for groundwater distillation as solar energy is both a pressing necessity and a vital supply for all living things. Solar energy utilization is essential due to increased global warming and pollution, and it is being replaced by the traditional use of fuels in the globe today. We majorly focus on the removal of harmful compounds such as arsenic and fluoride from the groundwater with the help of solar-powered distillation techniques. The role of renewable energy technology in the sustainability of future water systems with a growing demanding share of groundwater distillation is presented in this paper.
Показать больше [+] Меньше [-]Recovery of Fuels Using the Supramolecular Gelation Ability of a Hydroxybenzoic Acid Bisamide Derivative Полный текст
2021
Zapién-Castillo, Samuel | Montes-Patiño, Jorge Jesús | Pérez-Sánchez, Josué Francisco | Lozano-Navarro, Jessica Ismalé | Melo-Banda, José Aarón | Mésini, Philippe J. | Díaz-Zavala, Nancy Patricia
In order to remedy the environmental pollution caused by oil spills, new materials with gelation capacity of organic solvents and fuels have been synthetized during the recent years. Among them, some of the most promising materials contain amide groups, which are often incorporated into the chemical structure of organogelators due to their effectiveness in gelling organic solvents through hydrogen bonds. A bisamide derivative of hydroxybenzoic acid (Bis-HUB1) was designed and synthesized in two steps and is able to congeal organic solvents. Gelation tests, critical gelation concentrations, and gel-sol transition temperatures were discussed in terms of its supramolecular interactions. Intermolecular hydrogen bonds and π-π stacking were studied through variable-temperature FTIR and UV-visible spectroscopy, while the structural characterization was performed via freeze-fracture TEM. Interestingly, Bis-HUB1 showed the ability to gel gasoline and diesel from monophasic and biphasic systems, which implies its potential use as a remediation agent in fuel spills. The results encourage further research.
Показать больше [+] Меньше [-]Calculation of electronic and optical properties of methylammonium lead iodide perovskite for application in solar cell Полный текст
2021
Kumārī, Saritā | Meena, Arti | Singh, Amanpal | Verma, Ajay Singh
Organic-inorganic metal halide perovskite materials, i.e., ABX₃ (A = methylammonium, B = Pb, X = Cl, Br, I) have been proved to be outstanding for solar energy conversion. They provide a solution to renewable energy problems with good efficiency and cost-effective technology. Here, we report the initial calculations done by solving Kohn-Sham equations by the use of density function theory. The electronic structural and band gap of CH₃NH₃PbI₃ material are obtained by using different exchange-correlation potential (PBE, PBE-sol, GGA). Further, solar cell devices with CH₃NH₃PbI₃ as absorption layer and CdS/TiO₂/ZnTe as buffer layer have been modeled; device physics is discussed and performance of solar cell structure is analyzed in terms of short circuit current density, open circuit voltage, efficiency, fill factor, and quantum efficiency. The maximum efficiency of CH₃NH₃PbI₃ solar cell is found to be 19.6% with TiO₂ buffer layer, whereas efficiency with ZnTe buffer layer is also comparable which is 19.5%. Further the effect of layer thickness and temperature are analyzed for maximum efficiency.
Показать больше [+] Меньше [-]Abatement of gas-phase VOCs via dielectric barrier discharge plasmas Полный текст
2021
Panda, Pranita | Mahanta, Rajesh Kumar | Mohanty, Suchitra | Paikaray, Rita | Das, Smruti Prava
Non-thermal plasma (NTP) technology is regarded as promising method for abatement of volatile organic compounds (VOCs) and has gained substantial interests in the fields of air purification. In this present work at atmospheric pressure, dielectric barrier discharge (DBD) plasma has been employed and utilized to evaluate feasibility of toluene, benzene, and m-xylene degradation in a parallel plate type DBD reactor taking argon as a carrier gas. The composition of post-plasma-treated by-products is studied by various spectroscopic techniques such as GC, GCMS, and FTIR, and the corresponding computational work is carried out by Gaussian software. The by-products obtained are analyzed in order to ascertain their structure and stability. The degradation of the VOCs to CO and CO₂ has been affirmed from the GC and GCMS analyses. Furthermore, the probable degradation pathway for the degradation of the aforementioned VOCs has been deciphered and the most feasible path is suggested. Additionally, DFT calculations have been performed to have an idea about the energies of the pathways involved. This research work has been carried out without use of any catalyst. Surprisingly, the degradation observed is much higher than the reported values. These findings would be helpful towards the abatement of VOCs by the use of non-thermal plasma.
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