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Protective potential of curcumin or taurine on nephrotoxicity caused by bisphenol A Полный текст
2020
Aslanturk, Ayse | Uzunhisarcikli, Meltem
Bisphenol A (BPA) received heightened attention in the recent years due to humans continuously being exposed to it. This study explores the effect of taurine or curcumin on subacute BPA treatment-induced nephrotoxicity in rats (Rattus norvegicus). Forty-two adult albino male rats were exposed to BPA (130 mg/kg daily) for 28 days by gastric gavage. BPA led to lipid peroxidation, inhibiting antioxidant enzyme activities like catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione S-transferase (GST). BPA exposure also induced histopathological changes like tubular and glomerular degeneration, vascular congestion, and interstitial cell infiltration in kidney tissue. Cotreatment with taurine (100 mg/kg daily) or curcumin (100 mg/kg daily) alleviated the lipid peroxidation level and antioxidant enzyme activities and histological alterations brought about by BPA. In this study, curcumin and taurine application provided protection against renal toxicity caused by BPA but did not prevent toxic effect completely.
Показать больше [+] Меньше [-]Scientometric analysis and mapping of documentary array on the issue “Oil and petroleum products in soil and groundwater” Полный текст
2020
Busygina, Tatyana | Rykova, Valentina
The paper represents a scientometric analysis of a documentary array selected form Web of Science database on the issue “Oil and petroleum products in soil and groundwater.” The analysis of the array shows its positive dynamics since the mid-1990s and especially active growth recently; names of the countries and organizations most actively working on the aforementioned problem; authors leading by the number of publications; periodicals and serial publications with high publication activity; scientific meetings that discussed the problems of soils and groundwater contamination by oil and oil products; and the most cited publications. The authors carry out visualization of the scientific field “Oil and petroleum products in soil and groundwater” using CiteSpace software. Documents co-citation analysis with the CiteSpace revealed main research fronts: biotransformation, biodegradation of oil and oil products in the studied media, bioremediation of these media, new research trend related to unconventional methods of oil production. The CiteSpace also lets to identify within the document co-citation network prominent cited publications (according co-citation frequency, betweenness centrality, and the strength of citation bursts). The most prominent research direction—bioremediation—is identified.
Показать больше [+] Меньше [-]Synthesis and characterization of eco-friendly cellulose beads for copper (II) removal from aqueous solutions Полный текст
2020
Maaloul, Najeh | Oulego, Paula | Rendueles, Manuel | Ghorbal, Achraf | Díaz, Mario
In this study, novel cellulose-bead-based biosorbents (CBBAS) were successfully synthesized from almond shell using a simple three-step process: (i) dissolution of bleached almond shell in ionic liquid (1-butyl-3-methylimidazolium chloride), (ii) coagulation of cellulose-ionic liquid solution in water and (iii) freeze-drying. Their morphological, structural and physicochemical properties were thoroughly characterized. These biomaterials exhibited a 3D-macroporous structure with interconnected pores, which provided a high number of adsorption sites. It should be noted that CBBAS biosorbents were efficiently employed for the removal of copper (II) ions from aqueous solutions, showing high adsorption capacity: 128.24 mg g⁻¹. The biosorption equilibrium data obtained were successfully fitted to the Sips model and the kinetics were suitably described by the pseudo-second-order model. Besides, CBBAS biosorbents can be easily separated from the solution for their subsequent reuse, and thus, they represent a method for the removal of copper (II) from aqueous solutions that is not only eco-friendly but also economical.
Показать больше [+] Меньше [-]Evaluation of the Removal Efficiency of PCBs from Five Wastewater Treatment Plants in Jordan Полный текст
2020
Abu-Shmeis, Reham M. | Tarawneh, Ibrahim N. | Al-qudah, Yahya H. | Dabaibeh, Reem N. | Tarawneh, Mohammad N.
The levels of persistent organic pollutants, polychlorinated biphenyls (PCBs), were investigated in influent, effluent, and sludge of five wastewater treatment plants (WWTPs) in Jordan. Concentrations of 12 dioxin-like PCBs were determined. The extraction of PCBs from wastewater samples was done by solvent extraction using dichloromethane/hexane 1:1 mixture. The concentrated extracts were sequentially subjected to multilayer silica gel, basic alumina, and florisil chromatography columns for further cleanup. Sludge samples were extracted in a Soxhlet apparatus, using petroleum ether. PCB determination has been completed using gas chromatography equipped with mass spectrometry detector. The total concentrations of PCBs in influent samples ranged from 34.65 to 228.3 ng L⁻¹, in effluent samples from 16.1 to 123.88 ng L⁻¹, and in the sludge samples from 51.1 to 223.85 ng kg⁻¹. In three of the investigated wastewater treatment plants, the amount of PCBs in sludge exceeded the limit proposed by European Union legislation. The total removal efficiencies of the total PCBs were evaluated and ranged from 34.8 to 88.1% for Aqaba and Abu-Nsair WWTP, respectively. The values of incremental lifetime cancer risk due to exposure to PCBs in sludge samples were also estimated in this study, and they ranged from 2.415 × 10⁻⁷ to 1.193 × 10⁻⁶ for adults. The number of people suspected to have cancer due to the exposure to the sludge of the WWTPs in Jordan is between 4 and 20 out of ten million.
Показать больше [+] Меньше [-]The Influence of Cyclohexanone/Cyclohexanol on the Growth and Nitrogen Removal of Arthrospira platensis and the Cyclohexanone/Cyclohexanol Biotransformation Полный текст
2020
Liu, Caixia | Li, Xu | Li, Yeguang | Wen, Xiaobin
Arthrospira platensis is a candidate for removing nitrogen from caprolactam wastewater, but the concentrated cyclohexanone (CHN) and cyclohexanol (CHL) in the wastewater have an unknown effect on A. platensis growth. The aim of this study was to evaluate the feasibility of A. platensis for caprolactam wastewater treatment and obtain safe exposure concentrations of CHN and CHL. The biotransformation of CHN and CHL was investigated. Considering the changes of growth rate and pigment contents, the safe exposure concentrations of individual CHN and CHL were ≤ 800 and ≤ 400 mg L⁻¹, respectively. For binary mixture, the safe exposure concentration was ≤ 200 + 100 mg L⁻¹ CHN + CHL. Both chemicals induced decreased trichome length at all concentrations, but trichomes were large enough to be harvested efficiently by gravity filtration using filter membranes with a pore size of 25–40 μm under safe exposure. The nitrogen removal rate showed no difference in CHN and CHL treatment under safe exposure concentrations compared with the control, and the maximal nitrogen removal rate was 18.66 mg L⁻¹ d⁻¹. Besides, A. platensis catalyzed interconversion between CHN and CHL which preferred to convert CHN into CHL when chemicals coexisted. Results highlight the potential of A. platensis for the nitrogen removal from caprolactam wastewater when CHN and CHL were under the safe exposure concentrations.
Показать больше [+] Меньше [-]Hypomethylation of LINE-1 retrotransposons is associated with cadmium-induced testicular injury Полный текст
2020
Wang, Xiaofei | Wang, Mei | Zeng, Ling | Su, Ping
Retrotransposons, as vital regulator of male fertility, are essential for spermatogenesis. Cadmium (Cd) is an environmental toxicant and endocrine disruptor, targeting the reproductive system. Growing evidence shows that Cd exposure can induce male infertility in mammals. In this study, we generated a male C57BL/6 J mice model with consecutive 35 days cadmium chloride (CdCl₂) in different concentrations of 0, 0.25, 0.5, 1.0, and 2.0 mg/kg. The results indicated that 1.0 and 2.0 mg/kg CdCl₂ significantly affected the body weight. Meanwhile, the highest dose group with 2.0 mg/kg CdCl₂ presented low fertility. Furthermore, the expression of retrotransposon mRNA was markedly increased in the higher doses group. We examined methylcytosine (mC) levels of the three active LINE-1 subfamilies TfI, A, and GfII in testis. Conclusively, Cd exposure probably undermines the male mice fertility by disrupting DNA methylation to regulate the retrotransposons. Further studies are required for identifying whether retrotransposon activation has any significant impacts on genome structure, stability, and expression in Cd-induced testicular injury, laying foundation for the treatment for male infertility.
Показать больше [+] Меньше [-]Removal of antipyrine through two-dimensional and three-dimensional electrolysis: comparison, modification, and improvement Полный текст
2020
Liu, Pengxiao | Wang, Xu | Lü, Jing | Li, Ying | Hou, Bin | Feng, Ling
In this work, removal of antipyrine was studied through two-dimensional (2D) and three-dimensional (3D) electrolysis. 2D electrolysis was firstly studied with the Ti/SnO₂-Ta₂O₅-IrO₂ anode as working electrode. Operating parameters affecting antipyrine removal, such as current density, electrode distance, and initial concentration of antipyrine, were investigated and optimized. As the limited antipyrine removal efficiency of 48.0% was not satisfying, 3D electrolysis with γ-Al₂O₃ as particle electrodes was introduced in the purpose of improving the antipyrine removal. An obviously enhanced removal efficiency of 78.3% was obtained, which seemingly validated the effect of particle electrodes in improving antipyrine removal. Hence, an effort to further enhance the antipyrine removal efficiency was made through improving the electrochemical characteristics of γ-Al₂O₃ as particle electrodes. Modified Sn-Sb-Bi/γ-Al₂O₃ particles were thus prepared through impregnation method. And a desirable antipyrine removal efficiency of 94.4% and energy consumption of 0.18 kWh/g antipyrine were achieved in the 3D electrolysis with Sn-Sb-Bi/γ-Al₂O₃ as particle electrodes. Furthermore, possible mechanism and pathway of antipyrine degradation in 3D electrolysis were explored through detection of ·OH using terephthalic acid fluorescent probe method and detection of antipyrine degradation intermediates using LC-MS.
Показать больше [+] Меньше [-]Influence of Adsorbent/Adsorbate Interactions on the Removal of Cationic Surfactants from Water by Graphene Oxide Полный текст
2020
de Figueiredo Neves, Tauany | Kushima Assano, Patrícia | Rodrigues Sabino, Livia | Bardelin Nunes, William | Prediger, Patricia
This work addresses the synthesis of graphene oxide, its structural characterization, and its application in the removal of cationic surfactants from water. The synthesized graphene oxide was characterized by Raman, infrared and X-ray photoelectron spectroscopies, scanning and transmission electron microscopies, and zeta potential. After the nanomaterial structural elucidation, optimization tests, studies of kinetics, isotherm, and thermodynamics of adsorption were performed to study adsorbent/adsorbate interactions in the adsorption process of cationic surfactants on graphene oxide. Under optimized conditions, graphene oxide showed the highest removal potential for the pyridinium-containing surfactant (2083 mg/g), followed by the benzyl-containing surfactant (431 mg/g) and the tetrakyl surfactant (329 mg/g), suggesting that electrostatic, hydrophobic, and cation-π interactions are common in the process, but pyridinium-π and π-π interactions are stronger. In addition, the adsorbent, under optimized conditions, compared with other sorbents described in the literature, presented higher potential adsorption.
Показать больше [+] Меньше [-]A Full-Scale Case Study on the Leaching Process of Acid Rock Drainage in Waste Rock Piles and the Net Infiltration Through Cover Systems Полный текст
2020
Ma, Liang | Huang, Cheng | Liu, Zhong-Sheng | Morin, Kevin A. | Dy, Eben | Tufa, Kidus | Fisher, Elizabeth | Zhou, Jianqin | Aziz, Mike | Meints, Cody
The leaching process and drainage chemistry of acid rock drainage is mainly controlled by geochemical reactions and how water carries soluble reaction products in waste rock piles. This paper studied how water flows through a full-scale waste rock pile at the Equity Silver mine site in British Columbia, Canada and elaborated on their effects on the leaching process and drainage chemistry. A revised dual-permeability model coupled with mass transport was adopted to investigate preferential flow and matrix flow in the pile simultaneously while considering water and geochemical products leaching/exchange between them. Furthermore, a particle-level water film model and also the effects of air flow, oxygen transport, and heat transfer in pile scale were integrated to account for geochemical reactions. Simulation results of full-scale iron discharge showed that aqueous concentrations in drainage water did not vary significantly relative to variations in drainage flow rate, which was confirmed by 12 years of field monitoring data. In addition, the comparison of pre- and post-cover simulations with measured lime consumption during ARD treatment, and mass-balance/dilution calculations for the entire pile, indicates that roughly 15–20% of total precipitation passes through the cover.
Показать больше [+] Меньше [-]Does globalization in Turkey induce increased energy consumption: insights into its environmental pros and cons Полный текст
2020
Etokakpan, Mfonobong Udom | Adedoyin, Festus Fatai | Vedat, Yorucu | Bekun, Festus Victor
Globalization is the paradigm shift to a more integrated world economy broadly shaping economies and societies around the globe. The wave of globalization is much more eminent on its impact on increased energy demand, knowledge and technology transfer, trade, and financial capital flows. The present study focuses on Turkey, a fast-emerging economy that is no exception to the wave of globalization. This current study explores the dynamics between ecological footprints, energy consumption, and real income level for the case of Turkey in a carbon-income function while accounting for other covariate like globalization to avoid omitted variable bias. The study data spans from 1970 to 2017 on an annual frequency basis. The stationarity properties of the outlined variables were investigated. Subsequently, the equilibrium relationship between the variables is confirmed by the battery of recent robust estimation techniques. While to detect the causality of direction among the variables, the Modified Wald test causality test is utilized. This study reveals that an increase in energy consumption in Turkey reduces environmental pollution by a magnitude of 0.37% in the short run and 0.43% long run, while an increase in economic expansion dampens the quality of the environment 0.42% and 0.72% on both short and long-run basis. This is indicative given that Turkey is more energy conscious and energy efficient, while a positive statistically significant relationship is observed between real income level and ecological footprint and globalization index. The causality analysis also supports the growth-induced energy consumption hypothesis. The study further offers policy direction for the energy sector in Turkey in the face of global interconnectedness.
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