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Occurrence and removal of 10 odorous compounds in drinking water by different treatment processes Full text
2020
Feng, Guixue | Jia, Ruibao | Sun, Shaohua | Wang, Mingquan | Zhao, Qinghua | Xin, Xiaodong | Liu, Li
This study investigated the prevalence of ten odorous compounds (2-methylisoborneol, trans-1,10-dimethyl-trans-9-decalol, isophorone, 2,4,6-trichloroanisole, 2,3,6-trichloroanisole, 2,3,4-trichloroanisole, β-cyclocitral, β-ionone, 2-isobutyl-3-methyoxypyrazine, and 2-isopropyl-3-methoxypyrazine) in raw drinking water, as well as their removal by traditional processes, advanced oxidation processes, ultrafiltration, and nanofiltration processes, with the use of an ultrahigh-resolution Orbitrap. The most abundant odorous compounds referred to 2-methylisoborneol and trans-1,10-dimethyl-trans-9-decalol with maximal concentrations of 1.6 ng/L and 0.09 ng/L after treatment by traditional processes respectively, and their maximal concentration was 2.05 ng/L and lower than the detection limit after treatment by advanced oxidation processes, while the raw drinking water of the mentioned two processes was different. The high concentration of isophorone in water treated by traditional process, advanced oxidation process, and membrane process was also ascertained. On the whole, the removal rate of membrane process is the maximal for all odorous compounds except for 2,3,6-trichloroanisole, followed by the advanced oxidation process as well as the traditional process. Eight odorous compounds identified in raw water were preserved after traditional treatment, while five compounds were preserved after the advanced oxidation treatment. The combined ultrafiltration and nanofiltration with pre-flocculation was more effective than either the advanced oxidation process or the traditional treating process in removing odorous compounds, and over 90% of all the odorous compounds were removed. Further investigation is required to facilitate the removal of odorous compounds from drinking water by the incorporation of ultrafiltration and nanofiltration units based on current drinking water treatments.
Show more [+] Less [-]Microhabitat variables explain patch switching by wintering Bewick’s swans through giving-up net energy intake rates Full text
2020
Yu, Chao | Zhou, Lizhi | Mahtab, Nazia | Fan, Shaojun | Song, Yunwei
Microhabitat variables are determinants for animals to select forage patches and evaluate the cost/benefit tradeoffs of habitat switching. Optimal foragers would weigh habitat quality by giving-up net energy intake rate (GUN), which includes the energy intake rate and cost rate. The GUNs, energy intake rate, and cost rate can be influenced by variations in different microhabitat factors and interactive effects. In this study, we assessed the GUN patterns of wintering Bewick’s swans and the effects of microhabitat factors on their foraging strategy in three different habitats: foxnut ponds, paddy fields, and shallow lake. The foraging behaviors and microhabitat variables of the swans were investigated during the winters of 2016–2018 and 2017/2018 at Huangpi and Shengjin Lakes in Anhui Province, southeastern China. The results showed that the percentage of disturbance time and the giving-up food density in shallow water had significant negative effects on GUNs. In contrast, water depth and the giving-up food density in deep water showed positive effects on GUNs. GUNs were significantly different among the three habitats. GUNs also decreased as winter progressed. Swans would decrease their GUNs under unfavorable foraging conditions such as more disturbances; however, GUNs would increase with water depth and food availability in patches with deep water. The swans demonstrated diverse GUN patterns in different foraging habitats, driven by the tradeoffs between energy intake rates and energy cost rates that were influenced by microhabitat variables. It implies that waterbirds exposed to decreasing GUNs may mitigate energy demand and environmental stress by switching foraging habitat while in subprime foraging habitat if alternative habitats that offered higher net rates of energy gain were available.
Show more [+] Less [-]Phthalocyanine-sensitized evolution of hydrogen and degradation of organic pollutants using polyoxometalate photocatalysts Full text
2020
Wang, Ruixin | Liu, Yefeng | Zuo, Peng | Zhang, Zhendong | Lei, Nana | Liu, Yaqing
In this study, 2 (3), 9 (10), 16 (17), 23 (24)-tetrakis-(8-quinoline-oxy) phthalocyanine zinc(II) (ZnQPc) was prepared and then quaternized to obtain water soluble zinc phthalocyanine (ZnQPc⁴⁺). Then, ZnQPc⁴⁺ was used as a photosensitizer for a series of POM catalysts, including Dawson type K₆[α-P₂W₁₈O₆₂]·14H₂O (P₂W₁₈) and K₁₀[α-P₂W₁₇O₆₁]·20H₂O (P₂W₁₇) and Keggine type H₃PW₁₂O₄₀·xH₂O (PW₁₂). The Keggin type PW₁₂ showed higher efficiency with 18.2 μmol of H₂ evolution (turnover number (TON) = 14,550) for 6 h upon ZnQPc⁴⁺ sensitization in relation to two Dawson P₂W₁₇ and P₂W₁₈ in a visible light–driven water-soluble system with isopropanol and H₂PtCl₆·6H₂O. In addition, the complexes of ZnQPc⁴⁺ with a series of POM catalysts (P₂W₁₇, P₂W₁₈, and PW₁₂) were also used as photocatalysts for the degradation of methylene blue (MB) in water, and it was found that the complexes of ZnQPc⁴⁺ with P₂W₁₇ and PW₁₂ showed improved photocatalytic activity, and the degradation rates of MB reached 100% at a small dosage under natural pH and visible light. The high efficacy of POM catalysts for H₂ evolution and the degradation of MB were attributed to the sensitization of POMs by ZnQPc⁴⁺, which was enabled by the transfer of photogenerated electrons of ZnQPc⁴⁺ to the lowest unoccupied molecular orbital (LUMO) of POM.
Show more [+] Less [-]Effect of gibberellic acid on growth, biomass, and antioxidant defense system of wheat (Triticum aestivum L.) under cerium oxide nanoparticle stress Full text
2020
Iftikhar, Azka | Rizwan, Muhammad | Adrees, Muhammad | Ali, Shafaqat | ur Rehman, Muhammad Zia | Qayyum, Muhammad Farooq | Hussain, Afzal
Recently nanoparticles (NPs) are ubiquitous in the environment because they have unique characteristics which are the reason of their wide use in various fields. The release of NPs into various environmental compartments mainly ends up in the soil through water bodies which is a serious threat to living things especially plants. When present in soil, NPs may cause toxicity in plants which increase significance to minimize NPs stress in plants. Although gibberellic acid (GA) is one of the phytohormones that has the potential to alleviate abiotic/biotic stresses in crops plant, GA-mediated alleviation of cerium oxide (CeO₂) NPs in plants is still unknown, despite the large-scale application of CeO₂-NPs in various fields. The present study was performed to highlight the ability of foliar-applied GA in reducing CeO₂-NPs toxicity in wheat under soil exposure of CeO₂-NPs. We observed that CeO₂-NPs alone adversely affected the dry weights, chlorophyll contents, and nutrients and caused oxidative stress in plants, thereby reducing plant yield. GA coupled with CeO₂-NPs reversed the changes caused by CeO₂-NPs alone as indicated by the increase in plant growth, chlorophylls, nutrients, and yield. Furthermore, GA alleviated the oxidative stress in plants by enhancing antioxidant enzyme activities under CeO₂-NPs exposure than the NPs alone which further provided the evidence of reduction in oxidative damage in plants by GA. Overall, evaluating the potential of GA in reducing CeO₂-NPs toxicity in wheat could provide important information for improving food safety under CeO₂-NPs exposure.
Show more [+] Less [-]Trilemma assessment of energy intensity, efficiency, and environmental index: evidence from BRICS countries Full text
2020
Baloch, Zulifqar Ali | Tan, Qingmei | Iqbal, Nadeem | Mohsin, Muhammad | Abbas, Qaiser | Iqbal, Wasim | Chaudhry, Imran Sharif
This paper provides an assessment of energy density and energy efficiency and creates an important indicator of environmental performance. This article applied two mathematical models and econometric techniques to obtain detailed and specific results. The DEA and the non-normative account aggregation mean a collective aggregation to form a mathematical aggregation tool to create an environmental index for the BRICS countries (Brazil, Russia, India, China, and South Africa) based on available data from 2011 to 2016. The advantage of the proposed approach is to manage the irregularities of the data and follow the desired properties of the index number. The current paper is relevant for the broad scope of construction, the environmental index, and the evolution of the rankings of countries based on multiple indicators. Our results indicate that Brazil and Russia have the highest values of the Environmental Performance Index, which range between 67.44 and 60.70, respectively. India has a minimum value of 30.57 of the environmental index. The analysis shows that Brazil, Russia, and South Africa have the best scores and that these countries have the best results, while China and India also have the best results. This study can help form a valuable political tool for the development and development of the country’s politics.
Show more [+] Less [-]Ambient air pollution and its influence on human health and welfare: an overview Full text
2020
Almetwally, Alsaid Ahmed | Bin-Jumah, May | Allam, Ahmed A.
Human health is closely related to his environment. The influence of exposure to air pollutants on human health and well-being has been an interesting subject and gained much volume of research over the last 50 years. In general, polluted air is considered one of the major factors leading to many diseases such as cardiovascular and respiratory disease and lung cancer for the people. Besides, air pollution adversely affects the animals and deteriorates the plant environment. The overarching objective of this review is to explore the previous researches regarding the causes and sources of air pollution, how to control it and its detrimental effects on human health. The definition of air pollution and its sources were introduced extensively. Major air pollutants and their noxious effects were detailed. Detrimental impacts of air pollution on human health and well-being were also presented.
Show more [+] Less [-]Nanocurcumin improved glucose metabolism in streptozotocin-induced diabetic rats: a comparison study with Gliclazide Full text
2020
Afifi, Mohamed | Alkaladi, Ali | Abomughaid, Mosleh M. | Abdelazim, Aaser M.
In the present study, the biochemical effect of nanocurcumin (nanoCUR) compared with Gliclazide (GLZ) on the diabetic rats was studied. Forty male albino rats (Sprague Dawley) weighted 110 ± 20 g were used. Rats were randomly separated into two groups. Control, received no treatment. Streptozotocin (STZ)-induced diabetic groups take 5 ml/kg of STZ in normal saline daily for 30 days, further divided into diabetic non-treated group, did not receive any treatment: diabetic group treated by nanoCUR, received 15 mg/kg/day of nanoCUR orally for 30 days; diabetic group treated by GLZ, received 2 mg/kg/day of GLZ for 30 days. The mean body weights of all rats were registered and serum samples were collected for determination of fasting blood glucose (FBG), insulin concentration, liver glucokinase (GK), and glycogen synthase (GS) activities. Liver tissues were collected for determination of mRNA expression of insulin (INS), insulin receptor A (IRA), glucokinase (GK), and glucose transporter 2 (GLUT2). The results revealed a significant reduction of body weight in diabetic rats, with no significant differences in nanoCUR and GLZ groups. There was a decline in FBG levels and significant elevation of INS levels, GK, and GS activities in diabetic rats received nanoCUR and GLZ. mRNA expression of INS, IRA, GK, and GLUT2 significantly upregulated in diabetic rats received nanoCUR and GLZ. The amazing observation was a non-significant difference in all measured parameters between nanoCUR and GLZ groups. In conclusion, nanoCUR is able to improve cellular uptake of glucose, the hepatic insulin signaling, and insulin sensitivity in diabetic rats. Its effect was similar to standard hypoglycemic drug (GLZ).
Show more [+] Less [-]Oxidative state of the frugivorous bat Sturnira lilium (Chiroptera: Phyllostomidae) in agricultural and urban areas of southern Brazil Full text
2020
Oliveira, Fernanda Weinmann | Schindler, Monica Santin Zanatta | Corá, Denyelle Hennayra | Thiel, Nathana | Siebel, Anna Maria | Galiano, Daniel
Exposure to contaminants is one of the main threats to all living organisms. In this context, bats have been used to indicate environmental contaminants in urban and agricultural environments, since they are extremely sensitive to changes in the ecosystem and easily accumulate waste in their body tissues. Among bats, Sturnira lilium, is a frugivorous species widely distributed and abundant in Brazil that uses an extensive variety of habitats and shelters. In this study, we aimed to evaluate the oxidative state of S. lilium individuals in agricultural and urban areas in southern Brazil. Individuals were sampled in agricultural and urban areas from November 2017 to March 2018 through the mist-net method. Parameters of the superoxide dismutase (SOD) and catalase (CAT) enzyme activity, non-protein thiols (NPSH), and lipid peroxidation (TBARS) were determined based on liver tissue. A total of 46 individuals were captured, 29 of them in urban areas and 17 in agricultural areas. We found that S. lilium individuals from agricultural areas showed a significant increase in TBARS, NPSH, and SOD activity, compared to individuals from urban areas. The activity of the antioxidant enzyme CAT did not differ. The present findings suggest that the species S. lilium, which are widely distributed and abundant in Brazil in urban and agricultural areas, can usefully be employed in biomonitoring programs. Further studies are to be encouraged to refine our knowledge on the potential DNA damage caused by environmental contamination, as well as identify potential contaminants to bats.
Show more [+] Less [-]Preserving wheat grain quality and preventing aflatoxin accumulation during storage without pesticides using dry chain technology Full text
2020
Bakhtavar, Muhammad Amir | Afzal, Irfan
Storage of wheat in conventional packaging materials is not safe as seeds gain moisture from surrounding air of high relative humidity which promotes growth of fungal and insect pests and loss of quality during storage. Implementing the dry chain, initial drying to low moisture content followed by storage in hermetic bags to maintain low moisture may prevent these losses without using fumigants or chemicals. Different levels of initial moisture contents (SMC), i.e., 8, 10, 12, and 14% and packaging materials, including hermetic super bags along with paper, woven polypropylene (PP), jute, and cloth bags were used as two factors for this experiment. After 4 months of storage, small variation in SMC of seed was observed in super bags while SMC increased significantly in conventional packaging materials. Higher storage losses (≈9%), grain quality losses and aflatoxin B₁, B₂, G₁, and G₂ contamination (1–2 ppb) in conventional packaging materials were linked to high seed moisture contents. Storage in hermetic bags at 8 and 10% SMC ideally preserved seed quality. In conclusion, hermetic storage of wheat at low seed moisture maintains a dry chain and prevents aflatoxin contamination and grain quality losses and offers an organic approach to avoid contamination of food grains.
Show more [+] Less [-]Coordinated development of economic growth and ecological efficiency in Jiangsu, China Full text
2020
Wang, Shijin | Hua, Guihong | Yang, Lizhu
In order to realize sustainable development, ecological efficiency is particularly important and deserving of further study and discussion in China. Thus, the study proposed a comprehensive index for ecological efficiency in Jiangsu and evaluated the ecological efficiency of 13 cities in the year of 2007, 2012, and 2017 by using entropy-weighting TOPSIS method. Based on coupling model, the study discussed the interaction between economic growth and ecological efficiency in Jiangsu. The results indicated that the ecological efficiency of Jiangsu in these three years differed considerably. Ecological efficiency is the highest in central Jiangsu, whereas ecological efficiency in the northern and southern parts of Jiangsu is relatively low from the perspective of horizontal space. In terms of coupling, Wuxi and Suzhou were the stablest in southern Jiangsu. Economic growth in the central Jiangsu fluctuated, Suqian lagged. Furthermore, based on the findings, the industrial structure should be adjusted to improve ecological efficiency. In addition, the use of innovation and rational foreign direct investment and other measures should be promoted. These proposals aim at improving ecological efficiency and achieving overall sustainable development in Jiangsu, China.
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