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Investigation on the role of economic, social, and political globalization on environment: evidence from CEECs 全文
2020
Destek, Mehmet Akif
This study aims to investigate the impact of different dimensions of globalization (i.e., overall globalization index, economic globalization index, social globalization index, and political globalization index) on environmental pollution by incorporating the real gross domestic product and energy consumption in Central and Eastern European Countries (CEECs). In doing so, the annual period from 1995 to 2015 is examined with second-generation panel data methodologies to consider the possible cross-sectional dependence among observed countries. The findings show that increasing overall globalization, economic globalization, and social globalization increases the carbon emissions while increasing political globalization reduces the environmental pollution. In addition, it is also found that Environmental Kuznets Curve (EKC) hypothesis is confirmed.
显示更多 [+] 显示较少 [-]Optimising the measurement of peracetic acid to assess its degradation during drinking water disinfection 全文
2020
Zhang, Kejia | San, Yulong | Cao, Cong | Zhang, Tuqiao | Cen, Cheng | Zhou, Xinyan
Chlorine-based compounds have been used as a disinfectant in drinking water treatment plants for decades because of their excellent sterilisation efficiency and low cost. However, the formation of disinfection by-products during chlorination is a cause for concern. Peracetic acid (PAA) is a strong oxidant with a redox potential higher than that of chlorine and does not form harmful disinfection by-products. It is thus a potential alternative for chlorine-based disinfectants. However, PAA decomposes rapidly in water at a rate that is highly affected by many factors, such as organic compounds and pH. The aim of this study is to investigate the stability of PAA during drinking water disinfection. To accomplish this, we studied methods for rapid detection of residual PAA and PAA decay in drinking water. Residual PAA was detected in water by the spectrophotometry-total chlorine reagent (SPTCR) method with a PAA concentration range of 0.090–10 mg/L (R² = 0.9943). Decay tests of PAA in drinking water and other sources of water showed that the decay process conformed to the first-order kinetic model with fast and slow reactions. Among four factors, pH was the key factor in the decay process because an alkaline environment significantly promotes the decomposition of PAA. In addition, total organic carbon (TOC), conductivity, and initial PAA concentration also affected PAA decay. Experimental and statistical analyses suggested that these factors affected PAA decay in the following descending order of influence: TOC, initial PAA concentration, and conductivity. In real water matrices, the PAA decay rate increased with increasing initial PAA concentration.
显示更多 [+] 显示较少 [-]Exposure to ractopamine hydrochloride induces changes in heart rate and behavior in zebrafish embryos and larvae 全文
2020
Garbinato, Cristiane | Schneider, Sabrina Ester | Sachett, Adrieli | Decui, Laura | Conterato, Greicy M. | Müller, Liz Girardi | Siebel, Anna Maria
Different veterinary drugs have been widely found in surface and groundwater, affecting non-target organisms. Ractopamine (RAC) is one of these drugs found in water bodies. It is a β-adrenergic agonist used as a feed additive to modulate the metabolism, redirect nutrients from the adipose tissue towards muscles, and increase protein synthesis in swine, cattle, and turkeys. RAC shows toxicological potential, but there is no data about its impacts on the development of non-target organisms, such as zebrafish (Danio rerio). In this study, we evaluated the effect of the exposure to this feed additive on critical parameters (hatching, survival, spontaneous movement, heart rate, and exploratory and locomotor behavior) in zebrafish embryos and larvae. The animals were exposed to RAC hydrochloride at 0.1, 0.2, 0.85, 8.5, and 85 μg/L. Zebrafish exposed to the drug showed increased heart rate at all tested concentrations and alterations on locomotion and exploratory behavior at 85 μg/L. No changes were observed in the survival, hatching rate and spontaneous movement. Our results suggest that RAC present in the environment can induce disabling effects on non-target organisms and elicit an ecological imbalance by increasing the animals’ vulnerability to predation due to greater visibility.
显示更多 [+] 显示较少 [-]Removal of pharmaceutical compounds from aqueous solution by novel activated carbon synthesized from lovegrass (Poaceae) 全文
2020
Cimirro, Nilton F.G.M. | Lima, Eder C. | Cunha, Mariene R. | Dias, Silvio L. P. | Thue, Pascal Silas | Mazzocato, Ana C. | Dotto, Guilherme L. | Gelesky, Marcos A. | Pavan, Flávio André
In this work, lovegrass (Cpa), an abundant grass of the Poaceae family, was employed as feedstock for the production of activated carbon in a conventional furnace using ZnCl₂ as a chemical activator. The prepared material (Cpa-AC) was characterized by pH of the point of zero charges (pHₚzc), Boehm’s titration method, CHN/O elemental analysis, ATR-FTIR, N₂ adsorption/desorption curves, and SEM. This carbon material was used for adsorption of acetylsalicylic acid (ASA) and sodium diclofenac (DFC). FTIR analysis identified the presence of O-H, N-H, O-C=O), C-O, and aromatic ring bulk and surface of (Cpa-AC) adsorbent. The quantification of the surface functional groups showed the presence of a large amount of acidic functional groups on the surface of the carbon material. The isotherms of adsorption and desorption of N₂ confirm that the Cpa-AC adsorbent is mesopore material with a large surface area of 1040 m² g⁻¹. SEM results showed that the surface of Cpa-AC is rugous. The kinetic study indicates that the system followed the pseudo-second-order model (pH 4.0). The equilibrium time was achieved at 45 (ASA) and 60 min (DCF). The Liu isotherm model best fitted the experimental data. The maxima sorption capacities (Qₘₐₓ) for ASA and DFC at 25 °C were 221.7 mg g⁻¹ and 312.4 mg g⁻¹, respectively. The primary mechanism of ASA and DFC adsorption was justified considering electrostatic interactions and π-π interactions between the Cpa-AC and the adsorbate from the solution.
显示更多 [+] 显示较少 [-]Comprehensive integrated index–based geochemistry and hydrochemical analyses of groundwater resources for multiple consumptions under coastal conditions 全文
2020
Aminiyan, Milad Mirzaei | Aminiyan, Farzad Mirzaei
The primary objective of this study was to assess the quality of groundwater in the Guilan aquifer, a principal aquifer in the north of Iran, for drinking, irrigation, and industrial purposes. In this regard, groundwater samples have taken from a database provided by the Water Resources Authority of Guilan Province, Iran’s Ministry of Energy. The studied four main regions of this aquifer were Talesh, Astaneh, Lahijan, and Foomenat. Achieved results were compared with the maximum permissible limit values recommended by the World Health Organization (WHO) and Food and Agriculture Organization (FAO) water standards for drinking and agricultural purposes, respectively. Moreover, evaluation of water suitability for industrial application was determined. According to the different indices, groundwater quality is suitable for irrigation purposes in all studied areas. A Piper diagram illustrated that the most dominant water type was Ca-HCO₃ in the all studied areas. This result also is consistent with results from the analysis of mineral saturation index. Accordingly, the result of water quality index (WQI) revealed that the groundwater in the Guilan aquifer could categorize from excellent to poor quality classes. However, the majority of water samples in Astaneh region mostly fall into the poor water class. The calculation of corrosiveness and scaling indices as Ryznar stability index (RSI) illustrated that a large number of the samples could be classified into aggressive and very aggressive categories. The results additionally showed that tendency to form scale based on Puckorius scaling index (PSI) was observed in some groundwater samples. Overall, the status of groundwater quality in Talesh region was noteworthy better than the other studied regions, while Astaneh region is more vulnerable with elevated contents of ions and physicochemical parameters.
显示更多 [+] 显示较少 [-]Rapid and efficient removal of naproxen from water by CuFe2O4 with peroxymonosulfate 全文
2020
Bai, Rui | Xiao, Yong | Yan, Weifu | Wang, Siqi | Ding, Rui | Yang, Fan | Li, Junpeng | Lu, Xiaoquan | Zhao, Feng
Naproxen, a widely used nonsteroidal anti-inflammatory drug, has been detected in many environmental matrixes and is regarded as an emerging pollutant. Sulfate radical (SO₄·⁻) -based advanced oxidation processes have attracted wide attention due to their high efficiency and applicability in the removal of emerging contaminants. In this study, CuFe₂O₄ was used as an efficient catalyst to activate peroxymonosulfate to oxidize naproxen. The results suggested that 92.3% of naproxen was degraded and 50.3% total organic carbon was removed in 60 min in the presence of 0.3 g·L⁻¹ CuFe₂O₄ and 2 mM peroxymonosulfate. This degradation system showed strong adaptability in a wide pH range from 4.0 to 10.0. Free radical scavenger experiments and electron spin resonance analysis indicated that ¹O₂, ·OH, and SO₄·⁻ are the main active species. Finally, the potential degradation pathways of naproxen were proposed by detecting and analyzing the degradation products with ultra-high-performance liquid chromatography combined with mass spectrometry. The results of this study suggest that the CuFe₂O₄-activated peroxymonosulfate system is a promising technology for the removal of naproxen from natural water.
显示更多 [+] 显示较少 [-]Novel eco-friendly electrospun nanomagnetic zinc oxide hybridized PVA/alginate/chitosan nanofibers for enhanced phenol decontamination 全文
2020
Elkady, Marwa | Salama, Eslam | Amer, Wael A. | Ebeid, El-Zeiny M. | Ayad, Mohamad M. | Shokry, Hassan
In the current study, poly(vinyl alcohol)/alginate/chitosan (PVA/Alg/CS) composite nanofiber was immobilized with six different ratios of nanomagnetic zinc oxide (M-ZnO) (0 wt%, 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt%, and 1 wt%) via the electrospinning technique. The various fabricated composite (M-6) nanofibers were characterized using Fourier transform infrared (FTIR), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), atomic force microscope (AFM), thermogravimetric analysis (TGA), mechanical testing machine, and optical contact angle measurement. The fabricated composite nanofibers were applied for the adsorption of phenol from aqueous solutions. The 1.0 wt% M-ZnO/PVA/Alg/CS composite nanofibers were selected as the best phenol adsorbent with removal percentage of 84.22%. The influence of different processing parameter such as contact time, composite nanofiber dosage, pH, initial pollutant concentration, and temperature were examined. Increasing nanofiber dosage and the solution temperature was found to enhance the phenol adsorption onto the prepared nanocomposites. The maximum percentage of phenol removal was achieved at 84.22% after 90 min. Meanwhile, the maximum monolayer adsorption capacity (at pH = 5.0) was estimated to be 10.03 mg g⁻¹ at 25 °C. Kinetic, isotherm, and thermodynamic studies were designated to proof the endothermic, spontaneous, and thermodynamically nature of the phenol adsorption process. These outcomes indicate the effectiveness of the fabricated M-ZnO/PVA/Alg/CS nanofibers as adsorbent materials for phenol from aqueous solutions.
显示更多 [+] 显示较少 [-]Adsorption of Cu(II) and Ni(II) ions from wastewater onto bentonite and bentonite/GO composite 全文
2020
Chang, Yii Shiuan | Au, Pek Ing | Mubarak, Nabisab Mujawar | Khalid, Mohammad | Jagadish, Priyanka | Walvekar, Rashmi | Abdullah, Ezzat Chan
Two superior adsorbents, namely bentonite and graphene oxide (GO), were hybridised to study the removal of copper and nickel ions from synthetic and industrial wastewater. The as-synthesised GO, bentonite/GO and bentonite were characterised by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and N₂ adsorption-desorption analysis. The factors influencing the adsorption behaviours including contact time, initial solution pH, ionic strength, initial concentration of metal ions, temperature and adsorbent dosage were systematically investigated by batch equilibrium method. The adsorption equilibrium for copper and nickel onto bentonite was attained in 90 min while equilibrium was reached in 60 min on bentonite/GO. The adsorption of copper and nickel was pH-dependent in the range from pH 2 to pH 7 and from pH 2 to pH 8. Pseudo-first-order kinetic model excellently described the adsorption of copper and nickel onto bentonite and bentonite/GO. The equilibrium adsorption data was well described by the Langmuir isotherm model and the maximum adsorption capacity was 248.9 mg/g, 558.4 mg/g, 215.8 mg/g and 402.5 mg/g for bentonite-copper, bentonite/GO-copper, bentonite-nickel and bentonite/GO-nickel adsorption systems, respectively. The bentonite/GO composite exhibited a higher adsorption capacity of both cations from synthetic wastewater than pure bentonite owning to the synergistic effect between bentonite and GO. In all adsorption studies, copper was more efficiently removed than nickel due to its higher tendency to form bond with adsorbent surfaces. The adsorption of copper and nickel on bentonite/GO was mainly due to cation exchange, intermolecular and electrostatic interactions and physisorption dominated the adsorption processes. The practical application of bentonite/GO on adsorption of copper was investigated using real wastewater and its removal efficiency was beyond 98%. The excellent adsorption performances of composites for the copper and nickel removal from wastewater demonstrated its significant potential for pollution mitigations.
显示更多 [+] 显示较少 [-]Dynamics of the surface thermal landscape (STL) in northern slope of central Tianshan mountains, Xinjiang, NW China from 2000 to 2018 全文
2020
Qi, Yaxiao | Zhang, Fei | Fang, Chuanglin | Liu, Changjiang
Using the 2000–2018 MODIS Land Surface Temperature (LST) data and taking 11 cities (counties) in the northern slope of the central Tianshan Mountains in northwestern China as the study area, the spatial-temporal characteristics, landscape indices, centroid, and geo-information Tupu (carto-methodology in geo-information, CMGI) of surface thermal landscape (STL) were analyzed, and the paper draws the following results: (1) There are great differences in the diurnal and seasonal STL. The higher thermal levels are distributed more northerly in spring, summer, and autumn, and more southerly in winter. (2) In terms of class type level and landscape level, different landscape indices show different characteristics in diurnal and seasonal thermal landscapes. (3) Centroids at different thermal levels during the daytime are more dispersed than at nighttime in spring and summer, while the opposite is found in autumn. In winter, centroids of different thermal levels are concentrated in the southern and central-southern regions. During the period of 2000–2018, centroids of different thermal levels tend to move with the varying of STL. (4) The whole STL in same seasons changed little, transition usually happens between adjacent thermal levels. Overall, compared with the eastern monsoon area, there are similarities and differences in the characteristics of the STL.
显示更多 [+] 显示较少 [-]Protective potency of Astragalus polysaccharides against tilmicosin- induced cardiac injury via targeting oxidative stress and cell apoptosis-encoding pathways in rat 全文
2020
Awad, Ashraf | Khalil, Samah R. | Hendam, Basma M. | Abd El-Aziz, Reda M. | Metwally, Mohamed M. M. | Imam, Tamer S.
Tilmicosin (Til) was purposed to be used in the treatment of a wide range of respiratory diseases in livestock. However, undesirable adverse effects, cardiac toxicity, in particular, may be associated with Til therapy. In the present study, the response of adult rats administered Til subcutaneously at different doses (10, 25, 50, 75, and 100 mg/kg b.w.; single injection) was evaluated. Astragalus polysaccharide (AP) at two doses (100 and 200 mg/kg b.w.; intraperitoneally) was investigated for its potential to counteract the cardiac influences, involving the oxidative stress-induced damage and apoptotic cell death, elicited by the Til treatment at a dose of 75 mg/kg b.w. in rats. Til induced mortalities and altered the levels of the biomarkers for the cardiac damage, particularly in the rats treated with the doses of 75 and 100 mg/kg b.w.; similarly, morphological alterations in cardiac tissue were seen at all studied doses. AP was found to cause a significant (P ˂ 0.05) decline in the levels of impaired cardiac injury markers (troponin, creatine phosphokinase, and creatine phosphokinase-MB), improvement in the antioxidant endpoints (total antioxidant capacity), and attenuation in the oxidative stress indices (total reactive oxygen species, 8-hydroxy-2-deoxyguanosine, lipid peroxides [malondialdehyde], and protein carbonyl), associated with a significant (P ˂ 0.05) modulation in the mRNA expression levels of the encoding genes (Bcl-2, Bax, caspase-3, P53, Apaf-1, and AIF), related to the intrinsic pathway of apoptotic cell death in the cardiac tissue. AP administration partially restored the morphological changes in the rat’s heart. The highest protective efficacy of AP was recorded at a dose level of 200 mg/kg b.w. Taken together, these results indicated that AP is a promising cardioprotective compound capable of attenuating Til-induced cardiac impact by protecting the rat cardiac tissue from Til-induced apoptosis when administered concurrently with and after the Til injection.
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