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Investigation of heavy metal pollution in eastern Aegean Sea coastal waters by using Cystoseira barbata, Patella caerulea, and Liza aurata as biological indicators Texte intégral
2017
Aydın-Önen, S. | Öztürk, M.
In order to have an extensive contamination profile of heavy metal levels (Cd, Cu, Fe, Mn, Ni, Pb, and Zn), seawater, sediment, Patella caerulea, Cystoseira barbata, and Liza aurata were investigated by using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Samples were collected from five coastal stations along the eastern Aegean Sea coast (Turkey) on a monthly basis from July 2002 through May 2003. According to the results of this study, heavy metal levels were arranged in the following sequence: Fe > Pb > Zn > Mn > Ni > Cu > Cd for water, Fe > Cu > Mn > Ni > Zn > Pb > Cd for sediment, Fe > Zn > Mn > Pb > Ni > Cd > Cu for C. barbata, Fe > Zn > Mn > Ni > Pb > Cu > Cd for P. caerulea, and Fe > Zn > Mn > Cu > Ni > Pb > Cd for L. aurata. Moreover, positive relationships between Fe in water and Mn in water, Fe in sediment and Mn in sediment, Fe in C. barbata and Mn in C. barbata, Fe in P. caerulea and Mn in P. caerulea, and Fe in L. aurata and Mn in L. aurata may suggest that these metals could be originated from the same anthropogenic source. C. barbata represented with higher bioconcentration factor (BCF) values, especially for Fe, Mn, and Zn values. This observation may support that C. barbata can be used as an indicator species for the determinations of Fe, Mn, and Zn levels. Regarding Turkish Food Codex Regulation’s residue limits, metal values in L. aurata were found to be lower than the maximum permissible levels issued by Turkish legislation and also the recommended limits set by FAO/WHO guidelines. The results of the investigation indicated that P. caerulea, L. aurata, and especially C. barbata are quantitative water-quality bioindicators and biomonitoring subjects for biologically available metal accumulation for Aegean Sea coastal waters.
Afficher plus [+] Moins [-]Resistance of aerobic microorganisms and soil enzyme response to soil contamination with Ekodiesel Ultra fuel Texte intégral
2017
Borowik, Agata | Wyszkowska, Jadwiga | Wyszkowski, Mirosław
This study determined the susceptibility of cultured soil microorganisms to the effects of Ekodiesel Ultra fuel (DO), to the enzymatic activity of soil and to soil contamination with PAHs. Studies into the effects of any type of oil products on reactions taking place in soil are necessary as particular fuels not only differ in the chemical composition of oil products but also in the composition of various fuel improvers and antimicrobial fuel additives. The subjects of the study included loamy sand and sandy loam which, in their natural state, have been classified into the soil subtype 3.1.1 Endocalcaric Cambisols. The soil was contaminated with the DO in amounts of 0, 5 and 10 cm³ kg⁻¹. Differences were noted in the resistance of particular groups or genera of microorganisms to DO contamination in loamy sand (LS) and sandy loam (SL). In loamy sand and sandy loam, the most resistant microorganisms were oligotrophic spore-forming bacteria. The resistance of microorganisms to DO contamination was greater in LS than in SL. It decreased with the duration of exposure of microorganisms to the effects of DO. The factor of impact (IFDO) on the activity of particular enzymes varied. For dehydrogenases, urease, arylsulphatase and β-glucosidase, it had negative values, while for catalase, it had positive values and was close to 0 for acid phosphatase and alkaline phosphatase. However, in both soils, the noted index of biochemical activity of soil (BA) decreased with the increase in DO contamination. In addition, a positive correlation occurred between the degree of soil contamination and its PAH content.
Afficher plus [+] Moins [-]Enhanced degradation of acid red 1 dye using a coupled system of zero valent iron nanoparticles and sonolysis Texte intégral
2017
Thomas, Shoniya | Abraham, Sijumon V. | Aravind, Usha K. | Aravindakumar, Charuvila T.
The heterogeneous catalytic degradation of a model azo dye, acid red 1 (AR1), initiated by zero valent iron nanoparticles (ZVINP), and its synergic effect with ultrasound (US) have been investigated in the present study. The treatment of AR1 using ZVINP at pH 3 showed maximum efficiency in terms of colour removal (53.0%) and mineralization (48.5% TOC reduction) after 25 min of reaction. However, the coupling of this system with US showed an enhanced efficiency against the decolourization and mineralization of AR1. More than 95% colour removal was achieved within 5 min in the case of US/ZVINP system. Around 55% TOC reduction suggests the conversion of the parent molecules in to aromatic transformed products, and it is further supported by LC-Q-TOF analysis. The remarkably higher efficiency in the coupled system is attributed to the synergic effect of ZVINPs and ultrasound. The highest degradation rates observed at highly acidic (pH 3) and alkaline pH (pH 9) suggests that different mechanisms are operating at both pH. The products identified gave some insight into the mechanism. The ZVINPs prepared in the present study was easily recoverable (and reusable) and hence may be considered as an effective replacement for the conventional Fenton’s reagent.
Afficher plus [+] Moins [-]The typical MSW odorants identification and the spatial odorants distribution in a large-scale transfer station Texte intégral
2017
Sun, Zhongtao | Cheng, Zhaowen | Wang, Luochun | Lou, Ziyang | Zhu, Nanwen | Zhou, Xuejun | Feng, Lili
Odorants from municipal solid waste (MSW) were complex variable, and the screening of key offensive odorants was the prerequisite for odor control process. In this study, spatial odor emissions and environmental impacts were investigated based on a large-scale working waste transfer station (LSWTS) using waste container system, and a comprehensive odor characterization method was developed and applied in terms of the odor concentration (OC), theory odor concentration (TOC), total chemical concentration (TCC), and electric nose (EN). The detected odor concentration ranged from 14 to 28 (dimensionless), and MSW container showed the highest OC value of 28, EN of 78, and TCC of 35 (ppm) due to the accumulation of leachate and residual MSW. Ninety-two species odorants were identified, and H₂S, NH₃, benzene, styrene, ethyl acetate, and dichloromethane were the main contributors in the container, while benzene, m,p,x-xylene, butanone, acetone, isopropanol, and ethyl acetate were predominant in the compression surface (CS) and compression plant (CP). Side of roads (SR) and unload hall (UH) showed low odorous impact. Based on this odor list, 20 species of odor substances were screened for the priority control through the synthetic evaluation method, considering the odorants concentrations, toxicity, threshold values, detection frequency, saturated vapor pressure, and appeared frequency. Graphical abstract
Afficher plus [+] Moins [-]Treatment and reuse of textile wastewaters by mild solar photo-Fenton in the presence of humic-like substances Texte intégral
2017
Negueroles, P.G. | Bou-Belda, E. | Santos-Juanes, L. | Amat, A. M. | Arques, A. | Vercher, R. F. | Monllor, P. | Vicente, R.
In this paper, the possibility of reusing textile effluents for new dyeing baths has been investigated. For this purpose, different trichromies using Direct Red 80, Direct Blue 106, and Direct Yellow 98 on cotton have been used. Effluents have been treated by means of a photo-Fenton process at pH 5. Addition of humic-like substances isolated form urban wastes is necessary in order to prevent iron deactivation because of the formation of non-active iron hydroxides. Laboratory-scale experiments carried out with synthetic effluents show that comparable results were obtained when using as solvent water treated by photo-Fenton with SBO and fresh deionized water. Experiments were scaled up to pilot plant illuminated under sunlight, using in this case a real textile effluent. Decoloration of the effluent could be achieved after moderate irradiation and cotton dyed with this water presented similar characteristics as when deionized water was used.
Afficher plus [+] Moins [-]Effectiveness of carbon dioxide against different developmental stages of Cadra cautella and Tribolium castaneum Texte intégral
2017
Husain, Mureed | Sukirno, Sukirno | Meman, K̲h̲ālid Maḥmūd | Tufail, Muhammad | Rasool, Khawaja Ghulam | Alwaneen, Waleed Saleh | Aldawood, Abdulrahman Saad
Methyl bromide is an excellent fumigant but has been banned because it has high potential for depleting the ozone layer which leads to many environmental and human health hazard issues. In this connection, effectiveness of carbon dioxide (CO₂, 99.9%) was studied as an alternative to methyl bromide under various exposure timings, 25 ± 1 °C, against different developmental stages of the almond moth, Cadra cautella, and red flour beetle, Tribolium castaneum. In case of C. cautella, the LT₉₉ against adult, pupa, and larval stages was achieved after 37.5, 78.1, and 99.9 h of CO₂ application, respectively. While for T. castaneum, the LT₉₉ values were obtained after exposure timings of 29.3, 153.9, and 78.4 h against adult, pupa, and larval stages, respectively. Adults were very susceptible; in contrast, pupae and larvae were more tolerant. The susceptibility order was observed as follows: T. castaneum adult > C. cautella adult > C. cautella pupae > T. castaneum larvae > C. cautella larvae > T. castaneum pupae. This study could be useful in developing the management strategies to prevent stored dates from C. cautella and T. castaneum infestation.
Afficher plus [+] Moins [-]Genotypic differences in cadmium transport in developing barley grains Texte intégral
2017
Lin, Li | Chen, Fei | Cai, Yue | Chen, Zhong-Hua | Cao, Fangbin
Genotypic differences in cadmium (Cd) transport in developing grains of barley (Hordeum vulgare L.) were investigated using detached ears cultured in a nutrient solution containing 0.5 and 5 μM Cd. Cd concentration in each part of the ear in W6nk2 (a low-grain-Cd-accumulation genotype) was much less than in Zhenong8 (a high accumulator) with 0.5 μM Cd treatment. However, Cd concentration in W6nk2 grains increased with an increase in external Cd level and was similar to Zhenong8 with 5 μM Cd treatment. Awn removal, a high relative humidity (RH, 90%) and addition of sucrose markedly decreased grain Cd concentration in Zhenong8 but less affected Cd transport to grain in W6nk2. Stem girdling reduced Cd transport to developing grains with 5 μM Cd treatment, especially for W6nk2, whereas no effect was found in either genotype with low Cd treatment. Our results suggested that higher grain Cd in Zhenong8 is closely related to a larger capacity for xylem transport and is connected with Cd translocation in xylem and phloem sap.
Afficher plus [+] Moins [-]Validated electrochemical and chromatographic quantifications of some antibiotic residues in pharmaceutical industrial waste water Texte intégral
2017
Ibrahim, Heba K. | Abdel-Moety, Mona M. | Abdel-Gawad, Sherif A. | Al-Ghobashy, Medhat A. | Kawy, Mohamed Abdel
Realistic implementation of ion selective electrodes (ISEs) into environmental monitoring programs has always been a challenging task. This could be largely attributed to difficulties in validation of ISE assay results. In this study, the electrochemical response of amoxicillin trihydrate (AMX), ciprofloxacin hydrochloride (CPLX), trimethoprim (TMP), and norfloxacin (NFLX) was studied by the fabrication of sensitive membrane electrodes belonging to two types of ISEs, which are polyvinyl chloride (PVC) membrane electrodes and glassy carbon (GC) electrodes. Linear response for the membrane electrodes was in the concentration range of 10⁻⁵–10⁻² mol/L. For the PVC membrane electrodes, Nernstian slopes of 55.1, 56.5, 56.5, and 54.0 mV/decade were achieved over a pH 4–8 for AMX, CPLX, and NFLX, respectively, and pH 3–6 for TMP. On the other hand, for GC electrodes, Nernstian slopes of 59.1, 58.2, 57.0, and 58.2 mV/decade were achieved over pH 4–8 for AMX, CPLX, and NFLX, respectively, and pH 3–6 for TMP. In addition to assay validation to international industry standards, the fabricated electrodes were also cross-validated relative to conventional separation techniques; high performance liquid chromatography (HPLC), and thin layer chromatography (TLC)-densitometry. The HPLC assay was applied in concentration range of 0.5–10.0 μg/mL, for all target analytes. The TLC-densitometry was adopted over a concentration range of 0.3–1.0 μg/band, for AMX, and 0.1–0.9 μg/band, for CPLX, NFLX, and TMP. The proposed techniques were successfully applied for quantification of the selected drugs either in pure form or waste water samples obtained from pharmaceutical plants. The actual waste water samples were subjected to solid phase extraction (SPE) for pretreatment prior to the application of chromatographic techniques (HPLC and TLC-densitometry). On the other hand, the fabricated electrodes were successfully applied for quantification of the antibiotic residues in actual waste water samples without any pretreatment. This finding assures the suitability of the fabricated ISEs for environmental analysis.
Afficher plus [+] Moins [-]Bio-based degradation of emerging endocrine-disrupting and dye-based pollutants using cross-linked enzyme aggregates Texte intégral
2017
Vēlāyutan̲, T. A. | Asgher, Muhammad | Iqbal, Hafiz M. N. | Hu, Hongbo | Zhang, Xuehong
In this study, manganese peroxidase (MnP) from an indigenous white-rot fungus Ganoderma lucidum IBL-05 was insolubilized in the form of cross-linked enzyme aggregates (CLEAs) using various aggregating agents, i.e., acetone, ammonium sulfate, ethanol, 2-propanol, and tert-butanol, followed by glutaraldehyde (GA) cross-linking. The precipitant type, MnP, and GA concentrations affected the CLEAs activity recovery and aggregation yield. Among precipitants used, acetone appeared to be the most efficient aggregation agent, providing the highest activity recovery and aggregation yield of 31.26 and 73.46%, respectively. Optimal cross-linking was noticed using 2.0% (v/v) GA and 8:1 (v/v) MnP to GA ratio at 3.0 h cross-linking time under continuous agitation at 4 °C. The highest recovered activity and aggregation yield were determined to be 47.57 and 81.26%, respectively. The MnP-CLEAs, thus synthesized, were tested to investigate their bio-catalytic capacity for removing two known endocrine-disrupting chemicals (EDCs), e.g., nonylphenol and triclosan in a packed bed reactor system. The insolubilized MnP efficiently catalyzed the biodegradation of both EDCs, transforming over 80% in the presence of MnP-based system. A maximal of 100% decolorization was recorded for Sitara textile (SIT-based) effluent, followed by 95.5% for Crescent textile (CRT-based) effluent, 88.0% for K&N textile (KIT-based) effluent, and 84.2% for Nishat textile (NIT-based) effluent.
Afficher plus [+] Moins [-]Revisiting the environmental Kuznets curve and pollution haven hypotheses: MIKTA sample Texte intégral
2017
Bakirtas, Ibrahim | Çetin, Mümin Atalay
This study aims to examine the validity of the environmental Kuznets curve (EKC) and pollution haven hypotheses in Mexico, Indonesia, South Korea, Turkey, and Australia (MIKTA) countries from 1982 to 2011 by using a panel vector auto regressive (PVAR) model. Empirical findings imply that the EKC hypothesis is rejected by the MIKTA sample. However, PVAR estimations reveal Granger causality from income level, foreign direct investment (FDI) inward, and energy consumption to CO₂ emissions. Orthogonalized impulse-response functions are derived from PVAR estimations. According to the analysis results, the response of CO₂ emissions to a shock on FDI is positive. These results assert that FDI has a detrimental effect on environmental quality in MIKTA countries which means the pollution haven hypothesis is confirmed by the MIKTA sample. Therefore, MIKTA countries should revise their current economic growth plans to provide sustainable development and also re-organize their legal infrastructure to induce usage of renewable energy sources.
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