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Activation of peroxymonosulfate by Fe-N complexes embedded within SBA-15 for removal of organic contaminants via production of singlet oxygen Full text
2018
Yang, Qunfeng | Jia, Nanzhengfang | Shen, Chensi | Ma, Jianqing | Wen, Yuezhong
Persulfates are recognized as promising oxidants and an alternative to Fenton reaction for water treatment. However, activation methods in hand restrict the practical application. Herein, we explore the possibility of Fe-N complexes being a catalyst for persulfate activation for the first time. The catalyst denoted as Fe-Im-SBA was synthesized from ferric chloride, imidazole, and SBA-15 at high temperature. The internal pore structure of Fe-Im-SBA was maintained well; Fe, N and C elements are evenly distributed on the catalyst. This catalyst presents an extraordinarily catalytic activity for Rh B removal by PMS activation with a removal rate of Rh B that reached up to 97.0% in the first 5 min. It also performed well in a wide pH range with complete removal of Rh B in pH ranged from 0.5 to 10, suggesting the stability of this catalyst in both acidic and alkaline conditions. It also showed high adaptability to degrade different kinds of pollutants, which could give an attractive advantage of Fe-Im-SBA for environmental implications. Through X-ray absorption spectroscopies analysis, it shows that the active sites of Fe-Im-SBA are composed of Fe-N₄ sites and Fe₂–N₂ sites. ¹O₂ were proved to generate in the Fe-Im-SBA/PMS system and serve as the major ROS. Meanwhile, graphitic carbon can accelerate the transfer of electrons, which may also be the reason for its high catalytic performance.
Show more [+] Less [-]Removal of imidazolium- and pyridinium-based ionic liquids by Fenton oxidation Full text
2018
Gomez-Herrero, Esther | Tobajas, Montserrat | Polo, Alicia | Rodriguez, Juan J. | Mohedano, Angel F.
The oxidation of imidazolium (1-hexyl-3-methylimidazolium chloride, HmimCl) and pyridinium (1-butyl-4-methylpyridinium chloride, BmpyrCl) ionic liquids (ILs) by Fenton’s reagent has been studied. Complete conversion was achieved for both ILs using the stoichiometric H₂O₂ dose at 70 °C, reaching final TOC conversion values around 45 and 55% for HmimCl and BmpyrCl, respectively. The decrease in hydrogen peroxide dose to substoichiometric concentrations (20–80% stoichiometric dose) caused a decrease in TOC conversion and COD removal and the appearance of hydroxylated oxidation by-products. Working at these substoichiometric H₂O₂ doses allowed the depiction of a possible degradation pathway for the oxidation of both imidazolium and pyridinium ILs. The first step of the oxidation process consisted in the hydroxylation of the ionic liquid by the attack of the ·OH radicals, followed by the ring-opening and the formation of short-chain organic acids, which could be partially oxidized up to CO₂ and H₂O. At H₂O₂ doses near stoichiometric values (80%), the resulting effluents showed non-ecotoxic behaviour and more biodegradable character (BOD₅/COD ratio around 0.38 and 0.58 for HmimCl and BmpyrCl, respectively) due to the formation of short-chain organic acids. Graphical abstract ᅟ
Show more [+] Less [-]Mytilus galloprovincialis (Lamarck, 1819) spermatozoa: hsp70 expression and protamine-like protein property studies Full text
2018
Piscopo, Marina | Notariale, Rosaria | Rabbito, Dea | Ausio, Juan | Olanrewaju, OladokunSulaiman | Guerriero, Giulia
In this work, we describe results of the reproductive health monitoring studies in Mytilus galloprovincialis following spermatozoa hsp70 expression and protamine-like protein properties. Mussels control (ctr) were released within cages for 30 days in three different marine sites near Naples (Campania, Italy): Bagnoli south (BAs) and Bagnoli north (BAn), both close to a disposal metallurgical factory and in Capo Miseno (CM). Studies of hsp70 gene expression carried out, by RT-qPCR, in mussel spermatozoa have shown varied expression levels, particularly 5, 13, and 15-fold more than ctr in CM, BAs, and BAn, respectively, indicating highest involvement of stress proteins in spermatozoa of mussels in Bagnoli. In order to evaluate the possible risk on Mytilus galloprovincialis sustainability loss, electrophoretic analyses were performed on protamine-like proteins (PL) of collected spermatozoa. The results showed that CM PL were apparently unaltered with respect to ctr PL, while BAs and BAn PL appeared in part in the form of peptides and in part as bands with low mobility. Further, CM and BAs PL showed, by electrophoretic mobility shift assay, a decrease in DNA binding ability and a change in their DNA binding mode. The results of this investigation show the usefulness of the study of alterations of spermatozoa hsp70 expression and protamine-like protein properties for eco-toxicological evaluation using Mytilus galloprovincialis as a bioindicator.
Show more [+] Less [-]Evaluation of a dry filter for dust removal under laboratory conditions in comparison to practical use at a laying hen barn Full text
2018
Strohmaier, Carolina | Schmithausen, Alexander J. | Krommweh, Manuel S. | Diekmann, Bernd | Büscher, Wolfgang
The high amount of particulate matter from poultry houses in the exhaust air, especially at different types of laying hen barns, is the main challenge farmers are faced with concerning emissions. As a possibility for the mitigation of particulate matter in the outgoing air, a dry filter based on the principle of centrifugal force was investigated under laboratory and field conditions. Aerosol spectrometers were used for continuous measurements in raw and clean gas. Field experiments took place under summer and winter conditions, so that filter efficiency under different climate conditions could be compared and measurement values at the barn were continuously collected over 24-h periods. Data collected under laboratory conditions showed a high efficiency of the dry filter, whereas results of the field experiments differed in each size fraction of the particulate matter. These differences may be explained by the fact that under laboratory conditions, better circumstances for correct measuring were created, e.g., laminar flow of the air.
Show more [+] Less [-]A new concept for risk analysis relating to the degradation of water reservoirs Full text
2018
Boryczko, Krzysztof | Bartoszek, Lilianna | Koszelnik, Piotr | Rak, Janusz R.
This paper presents a proposal for a procedure by which to analyse the risk of reservoirs being degraded. The body of water assessed for its susceptibility to degradation in line with the proposed procedure is Myczkowce Reservoir, SE Poland. This reservoir has a maximum capacity of ten million m³ and helps provide hydropower, by serving as a surge tank located above the main Solina Reservoir. On the basis of an assessment of its morphometric and hydrological parameters, Myczkowce Reservoir was assigned to the low-resilience category where risk of degradation was concerned. The primary factors responsible for that are limited capacity in relation to shoreline length, a lack of thermal stratification, and a high value for the Schindler index. These and other environmental parameters provided for Myczkowce’s assignment to the category of susceptible to the impact of matter supplied by its catchment, with this reflecting the instantaneous nature of the basin, high values for the Ohle coefficient, average catchment slope, and the lack of a septic system. The designated risk level supported Myczkowce’s assignment to a category characterised by an “unacceptable” risk of degradation. The proposed method taking two parameters (resilience and susceptibility) into account represents the first universal method for assessing reservoirs without reference to risks such as drought, flooding, or lack of water supply for human consumption. The risk depends only on the reservoir and catchment parameters.
Show more [+] Less [-]Technical-financial evaluation of rainwater harvesting systems in commercial buildings–case ase studies from Sonae Sierra in Portugal and Brazil Full text
2018
Sousa, Vitor | Silva, Cristina Matos | Meireles, Inês C.
Water is an essential and increasingly scarce resource that should be preserved. The evolution of the human population and communities has contributed to the global decrease of potable water availability and the reduction of its consumption is now compulsory. Rainwater harvesting systems (RWHS) are emerging as a viable alternative source for water consumption in non-potable uses. The present study aims to contribute to the promotion of water efficiency, focusing on the application of rainwater harvesting systems in commercial buildings, and comprises four stages: (i) development of a technical evaluation tool to aid the design of RWHS and support their financial evaluation; (ii) validation of the tool using operational data from an existing RWHS installed at Colombo Shopping Center, in Lisbon, Portugal; (iii) assessment of the sensibility of the technical evaluation tool results to the variation of the inputs, namely the precipitation and consumption, through a parametric analysis for the Colombo Shopping Center; and (iv) comparison of the performance and financial feasibility of hypothetical RWHS in two existing commercial buildings. The technical tool was applied to two Sonae Sierra’s shopping centers, one in Portugal and one in Brazil. The installation of a 200-m³ tank is advised for the first case study, allowing non-potable water savings of 60% but a payback period of about 19 years. In the Brazilian shopping, the implementation of a tank with a capacity ranging from 100 to 400 m³ leads to non-potable savings between 20 and 50%, but with smaller payback period, under 2 years, due to the relatively lower investment costs and higher water fees.
Show more [+] Less [-]Radiation efficiency and nitrogen fertilizer impacts on sunflower crop in contrasting environments of Punjab, Pakistan Full text
2018
Nasim, Wajid | Ashfaq, Ahmad | Amin, Asad | T̤āriq, Muḥammad | Awais, Muhammad | Saqib, Muhammad | Jabran, Khawar | Shah, GhulamMustafa | Sultana, SyedaRefat | Hammad, HafizMohkum | Rehmani, MuhammadIshaq Asif | Hashmi, MuhammadZaffar | Rahman, MuhammadHabib ur | Turan, Veysel | Shah, Fahad | Suad, Shah | Khan, Aziz | Shahzād, ʻAlī
Sunflower (Helianthus annuus L.) is the leading non-conventional oilseed crop in Pakistan. Nitrogen fertilizer can affect plant growth and productivity by changing canopy size which has an effect on the radiation use efficiency (RUE) of the crop. The response of sunflower hybrids in terms of phenology, fraction of intercepted radiation (F ᵢ), and RUE to nitrogenous rates (0, 60, 120, 180, and 240 kg ha⁻¹) was studied in three field experiments conducted in three various environments: Multan (arid), Faisalabad (semi-arid), and Gujranwala (sub-humid) during spring seasons 2008 and 2009. The treatments were laid out according to a randomized complete block design with split plot arrangements, keeping the sunflower hybrids in main plots and nitrogen rates in sub-plots, and replicated three times. The results showed Hysun-38 took a maximum number of days to anthesis (101) as compared to Pioneer-64A93 (100) and Hysun-33 (99). The mean values of F ᵢ were 0.850, 0.903, and 0.978, and the estimated values of RUE for total aboveground dry matter were 2.14, 2.47, and 2.65 g MJ⁻¹ at experimental locations of Multan, Faisalabad, and Gujranwala, respectively. The values of RUE for grain yield (RUEGY) were 0.78, 0.98, and 1.26 g MJ⁻¹ at experimental locations of Multan, Faisalabad, and Gujranwala, respectively. The average RUEGY values over three locations were 2.61, 2.60, 2.43, and 2.36 g MJ⁻² in N₄ (180 kg ha⁻¹), N₅ (240 kg ha⁻¹), N₃ (120 kg ha⁻¹), and N₂ (60 kg ha⁻¹) treatments, respectively. Increasing rates of N increased RUEGY over the standard treatment N₃ (120 kg N ha⁻¹); however, the averaged values over three locations were 1.22, 1.08, 0.99, and 0.92 g MJ⁻² in N₄, N₅, N₃, and N₂ treatments, respectively. Therefore, optimum water and N doses are important for attaining higher RUE, which may enhance sunflower growth and yield.
Show more [+] Less [-]Correction to: Removal of fluoroquinolone from aqueous solution using graphene oxide: experimental and computational elucidation Full text
2018
Yadav, Sarita | Goel, Neetu | Kumar, Vinod | Tikoo, Kulbhushan | Singhal, Sonal
Unfortunately, the original version of this article contains a mistake. The figures no. 10, 11, 12 and 13 in the original version of the article should be replaced by the figures shown in this paper.
Show more [+] Less [-]A grey DEMATEL-based approach for modeling enablers of green innovation in manufacturing organizations Full text
2018
Gupta, Himanshu | Barua, MukeshKumar
Incorporating green practices into the manufacturing process has gained momentum over the past few years and is a matter of great concern for both manufacturers as well as researchers. Regulatory pressures in developed countries have forced the organizations to adopt green practices; however, this issue still lacks attention in developing economies like India. There is an urgent need to identify enablers of green innovation for manufacturing organizations and also to identify prominent enablers among those. This study is an attempt to first identify enablers of green innovation and then establish a causal relationship among them to identify the enablers that can drive others. Grey DEMATEL (Decision Making Trial and Evaluation Laboratory) methodology is used for establishing the causal relationship among enablers. The novelty of this study lies in the fact that no study has been done in the past to identify the enablers of green innovation and then establishing the causal relationship among them. A total of 21 enablers of green innovation have been identified; research indicates developing green manufacturing capabilities, resources for green innovation, ease of getting loans from financial institutions, and environmental regulations as the most influential enablers of green innovation. Managerial and practical implications of the research are also presented to assist managers of the case company in adopting green innovation practices at their end.
Show more [+] Less [-]Chiral triazole fungicide tebuconazole: enantioselective bioaccumulation, bioactivity, acute toxicity, and dissipation in soils Full text
2018
Cui, Ning | Xu, Haoyu | Yao, Shijie | He, Yiwen | Zhang, Hongchao | Yu, Yunlong
Enantioselectivity in environmental behavior and toxic effect of chiral pesticides has been received much attention. In this study, enantioselective bioactivity towards target organism Botrytis cinerea, acute toxicity and bioaccumulation in Eisenia fetida, and degradation in five kinds of soil under laboratory conditions regarding triazole fungicide tebuconazole were investigated. The results showed that fungicidal activity to Botrytis cinerea of R-(−)-tebuconazole was 44 times higher than S-(+)-tebuconazole with an order of R-(−)-tebuconazole > rac-tebuconazole > S-(+)-tebuconazole. No significant difference was found in acute toxicity of rac-, R-, and S-tebuconazole to E. fetida with 48-h EC₅₀ of 10.78, 10.48, and 10.84 μg/cm², respectively. Dissipation of tebuconazole in the five tested soils varied upon soil characteristics with half-life ranging from 32.2 to 216.6 days. Enantioselective and rapid dissipation of tebuconazole were observed in soils Hainan and Huajiachi, compared to the other soils. Enantioselective accumulation of tebuconazole in E. fetida was found with a preferential of S-(+)-tebuconazole although no significant difference in acute toxicity to E. fetida between rac-tebuconazole and enantiomers. The results indicated that S-(+)-tebuconazole with less fungicidal activity may be more likely to be accumulated in earthworm E. fetida. This research is helpful to better evaluate the environmental and ecological risk of tebuconazole on enantiomeric level.
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