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China’s CO2 emissions embodied in fixed capital formation and its spatial distribution Full text
2020
Gao, Ziyan | Geng, Yong | Wu, Rui | Zhang, Xi | Pan, Hengyu | Jiang, Huijuan
This study aims to measure China’s CO₂ emissions embodied in fixed capital formation (FCF) from 2007 to 2017 by using both a multi-regional input-output (MRIO) model and a single-region input-output model (SRIO). Then decoupling analysis was performed for uncovering the relationship between embodied CO₂ emissions and added values at provincial level. Logarithmic Mean Divisia Index (LMDI) method was further conducted to identify driving factors underlying the growth of embodied CO₂ emissions. Results show that CO₂ emission from FCF doubled from 2436 million tons (Mt) in 2007 to 4820 Mt in 2012, and increased slightly to 5089 Mt in 2017. Electric power, gas, and water production and supply sector (EGW) and manufacturing industry (MFI) sector were two dominant emitters from supply-side perspective, while construction (CON) was the largest demanding sector driving the embodied emissions from upstream sectors. From geographical point of view, northern provinces were the major inter-regional net exporters of embodied CO₂ emissions, while eastern and southern provinces were net importers of embodied CO₂ emissions. Based on such results, policy recommendations are proposed considering the relation between supply and demand sector, inter-provincial CO₂ emission transfer, and local economic development to mitigate CO₂ emissions from China’s FCF.
Show more [+] Less [-]Gum arabic and collagen hydrolysate extracted from hide fleshing wastes as novel wall materials for microencapsulation of Origanum onites L. essential oil through complex coacervation Full text
2020
Ocak, Bugra
Renewable resource–based biodegradable materials attract more attention than petroleum-based biodegradable materials to support the sustainable development of ecology. Obtaining collagen hydrolysate (CH) from hide fleshing wastes of leather industry is an environmentally friendly way to develop multifunctional materials that can contribute to technological advances in different industries. In this study, 2:1, 1:1, and 1 2 ratios of gum arabic (GA) and CH extracted from hide fleshing waste were used as wall materials to encapsulate Origanum onites L. essential oil (OOEO) using the complex coacervation method. The encapsulation yield and efficiency, functional group composition, particle size, morphology, and thermal stability of the obtained OOEO microcapsules were characterized. The results showed that the obtained microcapsules had high encapsulation yield and efficiency, as well as good functional properties such as uniform morphology and low water activity. The best mass ratio for the biopolymers (GA:CH) was 1:1. Scanning electron microscopy analysis showed that OOEO microcapsule samples had a spherical shape. FTIR analysis was performed on obtained microcapsules, confirming the molecular interactions between GA and CH. These findings can be useful in designing an ideal wall material using GA and CH for microencapsulation of essential oils by the complex coacervation method.
Show more [+] Less [-]Scheelite weathering and tungsten (W) mobility in historical oxidic-sulfidic skarn tailings at Yxsjöberg, Sweden Full text
2020
Hällström, Lina P.B. | Alakangas, Lena | Martinsson, Olof
More knowledge of the geochemical behavior of tungsten (W) and associated contamination risks is needed. Therefore, weathering of scheelite (CaWO₄) and secondary sequestration and transport of W to groundwater in historical skarn tailings and surface water downstream of the tailings were studied. The tailings contained 920 mg/kg W, primarily in scheelite. Mineralogical and geochemical analyses were combined to elucidate the geochemical behavior of W in the tailings, and water samples were taken monthly during 2018 to monitor its mobility. In the tailings, a large peak of W was found at 1.5 m depth. There, 30 wt%. of W was present in easily reducible phases, indicating former scheelite weathering. Currently, W is being released from scheelite to water-soluble phases at 2.5 m depth. The release of WO₄²⁻ is hypothetically attributed to anion exchange with CO₃²⁻ released from calcite neutralizing acid produced from pyrrhotite oxidation in the upper tailings and transported downwards to pH conditions > 7. Higher concentrations of dissolved W were found in the groundwater and particulate W in downstream surface water than in reference water, but they were lower than current contamination thresholds. Tungsten showed correlations with hydrous ferric oxides (HFO) in both the tailings and surface water.
Show more [+] Less [-]Polystyrene seedling trays used as substrate by native plants Full text
2020
Battisti, Corrado | Dodaro, Giuseppe | Fanelli, Giuliano
Among polymers, expanded polystyrene (EPS) is increasingly abundant as a form of anthropogenic litter in natural environments, particularly along waterways. Nevertheless, there is still no research focusing on the interaction between this type of litter and biodiversity components. In this note, we reported the first evidence of an interaction between EPS and living native plants along an artificial drainage channel in a land reclaimed area of Tyrrhenian central Italy. We sampled a number of EPS seedling trays, deriving from agricultural activities, obtaining evidence for an interaction between this polymer and plants: on a total of 231 available seedling holes, 16.88% have been occupied from six species (Lycopus europaeus, Poa cfr. trivialis, Stachys palustris, Silene sp., Phragmites australis, Parietariajudaica). The set of species occurring on floating polystyrene trays appears comparable to that occurring on the sides of the land reclaimed channels (locally, L. europaeus and S. palustris are among the most common species of the riverine vegetation). Therefore, it is very probable that floating trays are a random sample of the seed rain of the vegetation of the sides of the channels. However, more research is needed to assess if the plant assemblage growing on EPS is random process or if peculiar substrate exerts some sort of selection on the plant community.
Show more [+] Less [-]Temporal trend of arsenic in outdoor air PM2.5 in Wuhan, China, in 2015–2017 and the personal inhalation of PM-bound arsenic: implications for human exposure Full text
2020
Mao, Xiang | Hu, Xun | Wang, Yao | Xia, Wei | Zhao, Shasha | Wan, Yanjian
Arsenic in fine air particulate matter (PM₂.₅) has been identified as an important factor responsible for the morbidity of lung cancer, which has increased sharply in many regions of China. Some reports in China have shown that arsenic in the air exceeds the ambient air quality standard value, while long-term airborne arsenic concentrations in central China and human exposure via inhalation of PM–bound arsenic (inhalable airborne PM) have not been well characterized. In this study, 579 outdoor air PM₂.₅ samples from Wuhan, a typical city in central China, were collected from 2015 to 2017, and arsenic was measured by inductively coupled plasma-mass spectrometry. Personal exposure to PM-bound arsenic via inhalation and urinary arsenic concentration were also measured. The concentrations of arsenic in PM₂.₅ were in the range of 0.42–61.6 ng/m³ (mean 8.48 ng/m³). The average concentration of arsenic in 2015 (10.7 ng/m³) was higher than that in 2016 (6.81 ng/m³) and 2017 (8.18 ng/m³), exceeded the standard value. The arsenic concentrations in spring and winter were higher than those in summer and autumn. No significant differences (p > 0.05) were found among different sites. The daily intake of arsenic inhalation based on PM₁₀ samples collected by personal samplers (median, 10.8 ng/m³) was estimated. Urban residents inhaled higher levels of PM-bound arsenic than rural residents. Daily intake of arsenic via inhalation accounted for a negligible part (< 1%) of the total daily intake of arsenic (calculated based on excreted urinary arsenic); however, potential associations between the adverse effects (e.g., lung adenocarcinoma) and inhaled PM-bound arsenic require more attention, particularly for those who experience in long-term exposure. This study is the first report of a 3-year temporal trend of airborne PM₂.₅-bound arsenic in central China.
Show more [+] Less [-]Measurement of environmental efficiency in the countries of the European Union with the enhanced data envelopment analysis method (DEA) during the period 2005–2012 Full text
2020
Hermoso-Orzáez, Manuel Jesús | García-Alguacil, Miriam | Terrados-Cepeda, Julio | Brito, Paulo
In recent years, there has been growing interest in measuring the environmental efficiency of the different territories, countries, and/or nations. This has led to the development of different methods applied to the evaluation of environmental efficiency such as the data envelopment analysis (DEA) method. This method, supported by different studies, allows measuring relative environmental efficiency (eco-efficiency) and is consolidated as a very reliable method to measure the effectiveness of environmental policies in a specific geographical area. The objective of our study is the calculation of the environmental efficiency of the 28 member countries of the European Union (UE) through the DEA method. We will collect the data regarding the last years in which there are reliable comparative data in all. We will study in reference to them, the results of the environmental policies applied in the different countries, in order to make comparisons between countries and classify them according to their environmental efficiency. Using this, two variants of calculation within the DEA method to compare in a contrasted way the results of environmental efficiency for the 28 countries of the EU analyzed and propose possible solutions for improvement. Contributing in this work as main novelty the application of a new variant of the DEA method, which we will call improved analysis method (MAN) and that aims to agglutinate and assess more objectively, the results of the two DEA methods applied. The results show that there are 14 of the 28 countries that have a high relative environmental efficiency. However, we also find countries with very low environmental efficiency that should improve in the coming years. Coinciding precisely in this last group with countries recently admitted to the EU and where environmental policies have not yet been applied effectively and with positive results.
Show more [+] Less [-]Crayfish shell biochar modified with magnesium chloride and its effect on lead removal in aqueous solution Full text
2020
Zhang, Jiaqi | Hudielan, | Yan, Jinpeng | Long, Li | Xue, Yingwen
In this study, crayfish shell was pyrolyzed at 600 °C to obtain an unmodified biochar (CS600). MgCl₂ was used as a modifier to pretreat crayfish shell to produce a modified biochar (CS600-MgCl₂) under the same pyrolysis conditions. The two biochars were characterized for physicochemical properties and evaluated for lead (Pb²⁺) sorption ability to determine the modification mechanism. Mono-element batch adsorption experiments were conducted to compare the sorption performances of CS600 and CS600-MgCl₂ to Pb²⁺ in aqueous solutions. All the experiments were carried out at pH of 7. According to the Freundlich–Langmuir model, CS600-MgCl₂ had a higher adsorption capacity (152.3 mg/g) than CS600 (134.3 mg/g). FTIR, SEM, XRD, BET, and ICP analyses were applied to inform the interpretation of the mechanism. CS600 was calcium-rich and mainly removed Pb²⁺ through the ion exchange mechanism by replacing Ca²⁺ in the biochar. The increased Pb²⁺ adsorption capacity of CS600-MgCl₂ was mainly due to the enlarged specific surface area and the formation of Mg₃(OH)₅Cl·4H₂O on the modified biochar. Findings of this study suggest that both CS600 and CS600-MgCl₂ can be used to remove heavy metal ions from wastewater and MgCl₂ can improve the sorption performance of biochar.
Show more [+] Less [-]Rosa persica hydroalcoholic extract improves cadmium-hepatotoxicity by modulating oxidative damage and tumor necrosis factor-alpha status Full text
2020
Moradkhani, Shirin | Rezaei-Dehghanzadeh, Tayebeh | Nili-Ahmadabadi, Amir
Rosa persica is a member of the Rosaceae family that has a wide range of pharmacological properties. In this study, the antioxidant and therapeutic potential of this plant was investigated on cadmium (Cd)-induced hepatotoxicity. Rosa persica extract (RPE) was prepared by a maceration method in hydroalcoholic solvent, and its antioxidant properties were determined. Then, 36 mice were divided to six groups and treated for 2 weeks as follows: control, Cd (3 mg/kg), RPE (50 mg/kg), and groups 4–6 received Cd (3 mg/kg) and 12.5, 25, and 50 mg/kg of RPE respectively. The total polyphenol, flavonoids contents, and total antioxidant capacity in RPE were measured 263.4 ± 7.2 mg rutin equivalent/g extract, 72.3 ± 2.3 mg quercetin equivalent/g extract, and 8.46 ± 0.27 μmol ferrous sulfate/g extract, respectively. The in vivo results showed that Cd elicited remarkable hepatic injury that was manifested by the significant increase in serum hepatic enzymes. In addition, Cd significantly increased the levels of lipid peroxidation (LPO) and tumor necrosis factor-alpha (TNF-α) and decreased total thiol molecules (TTM) and total antioxidant capacity (TAC) in hepatic tissue. However, RPE decreased serum hepatic enzyme levels and improved oxidative hepatic damage by lowering the LPO and TNF-α levels and raising TAC and TTM in in Cd-treated groups. Although the RPE increased the metallothionein (MT) protein content, there was no change in MT gene expression. The present study showed that the RPE due to having antioxidant properties might partially prevent hepatic oxidative damage by the improvement of oxidant/antioxidant balance in animals exposed to Cd.
Show more [+] Less [-]Review on the occurrence and biological effects of illicit drugs in aquatic ecosystems Full text
2020
Fontes, Mayana Karoline | Maranho, Luciane Alves | Pereira, Camilo Dias Seabra
Illicit drugs (IDs) and their metabolites are recognized as contaminants of emerging concern. After consumption, illicit drugs are partially metabolized and excreted unchanged in urine and feces or as active metabolites reaching wastewater treatment plants (WWTPs). Furthermore, most WWTPs are insufficient in the treatment of effluents containing IDs, which may be released into aquatic ecosystems. Once in the water or sediment, these substances may interact and affect non-target organisms and some evidences suggest that illicit drugs may exhibit pseudo-persistence because of a continuous environmental input, resulting in long-term exposure to aquatic organisms that may be negatively affected by these biologically active compounds. We reviewed the literature on origin and consumption, human metabolism after consumption, aquatic occurrences, and toxicity of the major groups of illicit drugs (opioids, cannabis, synthetic drugs, and cocaine). As a result, it could be concluded that illicit drugs and their metabolites are widespread in diverse aquatic ecosystems in levels able to trigger sublethal effects to non-target organisms, besides to concentrate in seafood. This class of emerging contaminants represents a new environmental concern to academics, managers, and policymakers, whose would be able to assess risks and identify proper responses to reduce environmental impacts.
Show more [+] Less [-]Bladder entrance of microplastic likely induces toxic effects in carnivorous macrophyte Utricularia aurea Lour Full text
2020
Zhou, Jingzhe | Cao, Yu | Liu, Xiaoning | Jiang, Hongsheng | Li, Wei
The global distribution of microplastic (particle size < 5 mm) is of growing concern, especially in aquatic environments where it may cause adverse effects on resident organisms. To date, however, few studies have focused on the impacts of microplastic on aquatic plants. Here, we conducted a microcosm study to investigate the toxic effects of microplastic on the carnivorous aquatic macrophyte Utricularia aurea Lour. Based on microscopic images and Raman spectrum analysis, we found that most polyvinyl chloride (PVC) particles were smaller than the valve of U. aurea bladders, thus allowing entrance into the plant, but this was not so for polyethylene (PE) particles. Furthermore, PVC (50 mg L⁻¹) had significantly negative effects on growth and physiological parameters such as macrophyte length, chlorophyll content, and fluorescence, whereas, at the same concentration, PE had no such effects. Further analysis revealed that after bladder removal, the macrophytes did not respond to PVC particle toxicity. Thus, intake of microplastics (i.e., PVC) through bladders is likely responsible for inducing toxic effects to the growth and physiological parameters of U. aurea.
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