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Assessment of heavy metals in different organs of cattle egrets (Bubulcus ibis) from a rural and urban environment in Pakistan 全文
2019
Yasmeen, Roheela | Muhammad, Hifsa Ali | Bokhari, Syeda Shazia | Rafi, Uzma | Shakoor, Abdul | Qurashi, Aisha Waheed
The study was conducted to evaluate the concentration of essential elements (Cu, Fe, Mn, Ni, Se, Zn, and B) and non-essential elements (Cd, Pb, Hg, Cr, As, and Ni) in muscle, liver, bone, and intestine of matured cattle egret (Bubulcus ibis). Sampling was carried out at two sites of Lahore, Pakistan—Havalian Karbath (site I) and Mehmood Booti (site II)—over a period of 1 month in the winter season. Metal analyses of samples were carried out using inductively coupled plasma mass spectroscopy (ICPMS). The trend of essential elements in liver and intestine of site I was noticed as Fe > Zn > Cu > B > Mn > Se > Ni and almost same for bone and muscle as Fe > Zn > B > Mn > Cu > Se > Ni. It was noticed that Cu was less deposited in bone and muscle tissues compared to liver and intestine from site I. The deposition of essential elements in liver and intestine from site II was noticed as Fe > Zn > Cu > Mn > B > Se > Ni. Similar trend was found for bone and muscle: Fe > Zn > B > Mn > Cu > Se > Ni with great deposition of B than Cu compared to liver and intestine. The findings of the present study revealed almost similar trend for essential elements deposition at both sites. However, a random trend was observed for deposition of non-essential elements (Ag, As, Ba, Cd, Cr, Hg, Pb) in organs from both sites. Moreover, data showed higher levels of non-essential elements accumulation (particularly As, Ba, and Pb) in the body tissues/organs of cattle egret in an urban area (site II) as compared to rural area (site I) of Lahore. Furthermore, non-essential elements were more in intestine, bone, and muscles from site II showing more exposure to some non-essential elements at urban site due to human and natural activities. However, higher concentration of non-essential elements in liver from site I as compared to other organs not only reflect the land exposure to plant growth promoting fertilizers and sewage water for irrigation purpose but also better detoxification abilities of the rural birds. The study gave a new insight to inform contamination levels in the rural and urban sites. Future implications of this study need remediation strategies to clean environment requisite for avian species.
显示更多 [+] 显示较少 [-]Protective effect of different forms of nitrogen application on cadmium-induced toxicity in wheat seedlings 全文
2019
Yu, Lulu | Wang, Xinxia | Li, Xiaoyuan | Wang, Yi | Kang, Houyang | Chen, Guangdeng | Fan, Xing | Sha, Lina | Zhou, Yonghong | Zeng, Jian
Therefore, applying NH₄⁺-N tp PHW-SA caused greater tolerance to Cd toxicity by higher biomass production, photosynthetic capacity, Ca and Cu accumulation, better root development and lower translocation factor of Cd as well as Cd concetration in organelle fraction. The Cd stress inhibited the growth performance of wheat seedlings, the mineral nutrient accumulation, and nitrogen uptake and distribution, and different forms of nitrogen have different protective effects on wheat. In PHW-SA, ANCd treatment caused lower reduction in biomass accumulation, photosynthesis, isotope stable N content, Ca and Cu accumulation, root development inhibition, tissue Cd concentration, and transfer factor, which even led to lower concentrations of Cd in Fcₒ than those in Fcw and Fₛ in comparison with NNCd treatment. On the other hand, the converse growth performance was recorded in J-11 under ANCd treatment. Meanwhile, the nitrogen absorption preference in PHW-SA was altered along with the enhanced absorption efficiency of nitrogen. Therefore, applying NH₄⁺-N to PHW-SA caused greater tolerance to Cd toxicity by higher biomass production, photosynthetic capacity, Ca and Cu accumulation, better root development and lower translocation factor of Cd as well as Cd concetration in organelle fraction..
显示更多 [+] 显示较少 [-]How do fungal communities and their interaction with bacterial communities influence dissolved organic matter on the stability and safety of sludge compost? 全文
2019
Zhao, Xinyu | Wei, Yuquan | Zhang, Fang | Tan, Wenbing | Fan, Yuying | Xi, Beidou
This study was conducted to assess the effect of fungal communities and their interaction with bacterial communities on the dissolved organic matter (DOM) transformation for the stability and safety of sludge composting. The results showed that fungal community had strong shifts in diverse stages of sludge composting along with the changes of temperature. Correlation analysis demonstrated that fungal communities had significant connections with bacterial communities during composting but were not directly related to the indicators of phytotoxicity and maturity. Variance partitioning analysis suggested that the interactions of fungal and bacterial communities had the biggest contribution (49.75%) to composting stability and safety. Based on structural equation modeling, the possible way of fungal community participated in the transformation of DOM components and the formation of humic-like substances of DOM by interacting with bacterial community was proposed, which will provide important information for understanding the biotic interaction in composting and improving composting fermentation process.
显示更多 [+] 显示较少 [-]Using in situ modification to enhance organic fouling resistance and rejection of pharmaceutical and personal care products in a thin-film composite nanofiltration membrane 全文
2019
Lin, Yi-Li | Tsai, Jia-Zheng | Hung, Chung-Hsuang
A commercially available nanofiltration membrane, NF90, was modified using an in situ concentration polarization-enhanced radical graft polymerization method to improve the organic fouling resistance as well as the removal of pharmaceutical and personal care products (PPCPs), including ibuprofen (IBU), carbamazepine, sulfadiazine, sulfamethoxazole, sulfamethazine, and triclosan (TRI). 3-Sulfopropyl methacrylate potassium salt (SPM) and 2-hydroxyethyl methacrylate (HEMA) were used in various dosages for surface modification, and the extent of membrane modifications was quantified based on the degree of grafting. The modified NF90 exhibited a 15–40% lower flux during humic acid (HA) fouling and 25% greater NaCl rejection compared with the virgin membrane. PPCP rejection in the modified NF90 membranes before and after HA fouling was 20–45% and 5–20% greater, respectively, compared with that of the virgin membrane. Both SPM and HEMA increased the hydrophilicity of NF90 by decreasing contact angles. Scanning electron microscopy revealed lower amounts of foulants on the modified NF90 than on the virgin membrane. The main fouling mechanism for virgin NF90 was gel layer formation and those for modified NF90 were complete and intermediate blocking. Therefore, the modification of NF90 was effective for controlling organic fouling and strongly rejecting PPCPs.
显示更多 [+] 显示较少 [-]Determining the effects of aeration intensity and reactor height to diameter (H/D) ratio on granule stability based on bubble behavior analysis 全文
2019
Zhou, Jia heng | Zhou, Yun cheng | Yu, Hao cheng | Zhao, Yi qun | Ye, Kai qiang | Fang, Jing yuan | Wang, Hong yu
Aerobic granular sludge was considered as a leading wastewater technology in the next century. However, the loss of granule stability limited the application of this promising biotechnology. Increasing aeration intensity and height to diameter (H/D) ratio were conventional strategies to enhance granule stability. In this study, hydraulic effects of aeration intensity and H/D ratio were explored basing on bubble behavior analysis. However, results revealed that due to viscous resistance, increasing aeration intensity and H/D ratio had limited effects on enhancing hydraulic shear stress, not to mention the extra operation and construction cost. A deflector component was further applied to regulate hydraulic shear stress on large granules under low aeration intensity and H/D ratio. Hydraulic shear stress of large granules was constantly around 3.0 times higher than that in the conventional reactor, resulting in higher percentage of granules within optimal size range (81.95 ± 5.13%). A high abundance of denitrifying bacteria was observed in reactors, which led to high TN removal efficiency of 88.6 ± 3.8%.
显示更多 [+] 显示较少 [-]Investigating the nexus among environmental pollution, economic growth, energy use, and foreign direct investment in 6 selected sub-Saharan African countries 全文
2019
Ssali, Max William | Du, Jianguo | Mensah, Isaac Adjei | Hongo, Duncan O.
This research seeks to enhance the current literature by exploring the nexus among environmental contamination, economic growth, energy use, and foreign direct investment in 6 selected sub-Saharan African nations for a time of 34 years (1980–2014). By applying panel unit root (CADF and CIPS, cross-sectional independence test), panel cointegration (Pedroni and Kao cointegration test, panel PP, panel ADF), Hausman poolability test, and an auto-regressive distributed lag procedure in view of the pooled mean group estimation (ARDL/PMG), experimental findings disclose that alluding to the related probability values, the null hypothesis of cross-sectional independence for all variables is rejected because they are not stationary at levels but rather stationary at their first difference. The variables are altogether integrated at the same order I(1). Findings revealed that there is a confirmation of a bidirectional causality between energy use and CO₂ in the short-run and one-way causality running from energy use to CO₂ in the long run. There is additionally a significant positive outcome and unidirectional causality from CO₂ to foreign direct investment in the long run yet no causal relationship in the short run. An increase in energy use by 1% causes an increase in CO₂ by 49%. An increase in economic growth by 1% causes an increment in CO₂ by 16% and an increase in economic growth squared by 1% diminishes CO₂ by 46%. The positive and negative impacts of economic growth and its square approve the EKC theory. To guarantee sustainable economic development goal, more strict laws like sequestration ought to be worked out, use of sustainable power source ought to be stressed, and GDP ought to be multiplied to diminish CO₂ by the utilization of eco-technology for instance carbon capturing, to save lives and also to maintain a green environment.
显示更多 [+] 显示较少 [-]Sodium dodecyl sulfate-coated-cationized agroforestry residue as adsorbent for benzene-adsorptive sequestration from aqueous solution 全文
2019
Kong, Helen | Saman, Norasikin | Tee, Pei Nee | Cheu, Siew Chin | Song, Shiow Tien | Johari, Khairiraihanna | Lye, Jimmy Wei Ping | Che Yunus, Mohd Azizi | Mat, Hanapi
The aim of this work is to convert agroforestry residue to a novel adsorbent (M-1CTA-SDS-BT) used for adsorptive benzene sequestration from aqueous solution. In this study, the anionic surfactant-coated-cationized banana trunk was synthesized and characterized for batch adsorption of benzene from aqueous solution. The surface morphology, surface chemistry, surface area, and pore properties of the synthesized adsorbents were examined. It was proven that surface cationization successfully increased the benzene adsorption capacity of sodium dodecyl sulfate-coated adsorbents. The Langmuir isotherm model satisfactorily described the equilibrium adsorption data. The maximum benzene adsorption capacity (qₘₐₓ) of 468.19 μmol/g was attained. The kinetic data followed the pseudo-second-order kinetic model in which the rate-limiting step was proven to be the film diffusion. The batch-adsorbent regeneration results indicated that the M-1CTA-SDS-BT could withstand at least five adsorption/desorption cycles without drastic adsorption capacity reduction. The findings demonstrated the adsorptive potential of agroforestry-based adsorbent as a natural and cheap material for benzene removal from contaminated water.
显示更多 [+] 显示较少 [-]Forecasting number of ISO 14001 certifications of selected countries: application of even GM (1,1), DGM, and NDGM models 全文
2019
Ikram, Muhammad | Mahmoudi, Amin | Shah, Syed Zulfiqar Ali | Mohsin, Muhammad
The adaptability of ISO 14001 is considered as one of the most useful tools for environmental sustainability and worldwide competitive advantage; however, the future of ISO 14001 certification faces some uncertainties because of its uneven acceptance in various countries. These uncertainties, if not properly managed, can hinder the implementation of business management systems in these countries. In order to guide policymakers in better management of ISO 14001 in future with certainty, this study aims to forecast the ISO 14001 certifications for 10 years for China, India, the USA, Italy, Japan, and Germany, the top six certified countries, through advanced mathematical modeling, namely grey models, even GM (1,1), discrete GM (1,1), and non-homogenous discrete grey model (NDGM). The benefits of mentioned models are ensured accuracy in assessment using small samples and poor information. Moreover, current research is a pioneer in the certifications growth analysis using the Synthetic Relative Growth Rate and Synthetic Doubling Time models. Finally, the empirical analysis indicated that China is constantly leading in terms of its ISO 14001 certifications till 2026 and the performance of developing countries was spectacular. Furthermore, the article has proposed some suggestions for the policymakers to make the environment more sustainable.
显示更多 [+] 显示较少 [-]Monitoring the release of anti-inflammatory and analgesic pharmaceuticals in the receiving environment 全文
2019
Aydin, Senar | Aydin, Mehmet Emin | Ulvi, Arzu
The occurrence of anti-inflammatory and analgesic pharmaceuticals (AIAPs) in the effluents of 16 hospitals, influent and effluent of wastewater treatment plant (WWTP), the contribution and mass load of each hospital to WWTP influent, and the removal efficiencies in WWTP were investigated. Environmental risk was also evaluated by toxicity tests using organisms from three different trophic levels. Acetaminophen had the highest concentration in summer and winter samples, followed by ketoprofen, ibuprofen, and naproxen. The total daily load of AIAPs detected in influent of WWTP was 1677 mg/day/1000 inhabitants in summer and 5074 mg/day/1000 inhabitants in winter. The contribution of 16 hospitals to the total AIAP load in influent of WWTP was 11.30% in summer and 7.09% in winter. The highest mass loads were calculated as 203 mg/bed.day in general hospital in summer and 300 mg/bed.day in pediatric hospital in winter. The removal efficiencies of AIAPs in WWTP ranged between 13% and 100% in summer and 0.88% and 99% in winter. WWTP is not sufficient to remove all the AIAPs. Diclofenac (in summer), mefenamic acid, indomethacin, and phenylbutazone exhibited poor removal below 50%. The effluents of the WWTP exhibited a low risk for fish and Daphnia magna and an insignificant risk for algae.
显示更多 [+] 显示较少 [-]Assessment of mercury emissions into the atmosphere from the combustion of hard coal in a home heating boiler 全文
2019
Dziok, Tadeusz | Grzywacz, Przemysław | Bochenek, Piotr
The purpose of the paper was to determine the factor of mercury emission into the atmosphere by households in Poland. Research for a home coal-fired boiler typical of Polish conditions was carried out, which was conducted throughout the heating season. On the basis of assessment of the quantity of coal burned and mercury content contained therein, as well as of the mercury content in bottom ash, chimney soot, boiler deposits and their quantities, annual mercury emissions and its factor of emission into the atmosphere were defined. It was defined that the mercury emission factor for the investigated case of a single-family house is at a level of 0.56 μg/MJ. It was shown that 41.4% of the mercury contained in coal burned in a home heating boiler is emitted into the atmosphere, 57.0% is adsorbed by chimney soot, 0.3% by boiler heater deposits and 1.3% passes into bottom ash. Annual mercury emissions into the atmosphere from the single-family house concerned was 79 mg. Mercury emissions can be significantly reduced by households by separating any overgrowths with pyrite from coal. The solution proposed would enable a reduction in annual mercury emissions into the atmosphere in Poland from the domestic user sector by 58.5% (0.351 Mg). The factor of emission of mercury into the atmosphere would be 0.23 μg/MJ.
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