Dehghani M.H.,Tehran University of Medical Sciences |
Dehghani M.H.,Institute for Environmental Research |
Sanaei D.,Tehran University of Medical Sciences |
Ali I.,Jamia Millia Islamia University |
Bhatnagar A.,University of Eastern Finland
Journal of Molecular Liquids | Year: 2016
In the present study, treated waste newspaper (TWNP) was used to remove chromium(VI) from aqueous solution using batch experiments. The adsorption parameters optimized were: initial Cr(VI) concentration (5, 20, 50 mg/l), contact time (60 min.), adsorbent dose (3.0 g/L), and solution pH (3.0). The experimental data fitted well to Langmuir isotherm (R2 = 0. 98; maximum adsorption capacity 59.88 mg/g.) and pseudo-second-order kinetic model. The rate constant k2 varied from 0.0019 to 0.0068 at initial Cr (VI) concentration from 5 to 20 mg/L. It was observed that adsorption of Cr(VI) was pH dependent. The percentage removal of Cr(VI) was 59.88 mg/g (64% at pH 3). The results of the present study suggest that TWNP may be used as a low-cost adsorbent for the removal of chromium (VI) from aqueous solutions. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.
Delitala A.M.S.,Consorzio Interuniversitario Nazionale per la Fisica delle Atmosfere e delle Idrosfere |
Gallino S.,Consorzio Interuniversitario Nazionale per la Fisica delle Atmosfere e delle Idrosfere |
Villa L.,Consorzio Interuniversitario Nazionale per la Fisica delle Atmosfere e delle Idrosfere |
Lagouvardos K.,Institute for Environmental Research |
Drago A.,University of Malta
Theoretical and Applied Climatology | Year: 2010
The selection of ship routes based on modern weather forecasting is a mean of computing optimum shipping routes thereby increasing safety and comfort at sea, cutting down on transit time, and reducing fuel consumption. Further empirical research in the effectiveness of modern weather routing applications is required especially in applications concerning shorter routes in enclosed seas of limited geographical extent such as the Mediterranean Sea. The present study used two climatological simulations to test this state-of-the-art approach to ship routing. Simulations represented two theoretical routes: (1) a route between Italy and Greece and (2) a route between Cyprus and Italy. Both routes were analyzed across varying simulated climatic conditions and the results were compared with those of control routes. Furthermore, results were analyzed in terms of passenger and crew comfort, bunker consumption by ships, and time of crossing. The first simulation showed that weather routing would improve ship performance on 37% of days while the second simulation revealed that weather routing would support ship captains virtually all the time. © 2010 Springer-Verlag.
Hembrow S.C.,Southern Cross University of Australia |
Taffs K.H.,Southern Cross University of Australia |
Atahan P.,Institute for Environmental Research |
Parr J.,Southern Cross University of Australia |
And 2 more authors.
Science of the Total Environment | Year: 2013
Climate change is impacting global surface water resources, increasing the need for a deeper understanding of the interaction between climate and biological diversity. This is particularly the case in the Southern Hemisphere sub-tropics, where little information exists on the aquatic biota response to climate variations. Palaeolimnological techniques, in particular the use of diatoms, are well established and can significantly contribute to the understanding of climatic variability and the impacts that change in climate have on aquatic ecosystems. A sediment core from Lake McKenzie, Fraser Island (Australia), was used to investigate interactions between climate influences and aquatic ecosystems. This study utilises a combination of proxies including biological (diatom), geochemical and chronological techniques to investigate long-term aquatic changes within the perched-dune lake. A combination of 210Pb and AMS 14C dates showed that the retrieved sediment represented a history of ca. 37,000cal.yBP. The sedimentation rate in Lake McKenzie is very low, ranging on average from 0.11mm to 0.26mm per year. A sediment hiatus was observed between ca. 18,300 and 14,000cal.yBP suggesting a period of dry conditions at the site. The diatom record shows little variability over the period of record, with benthic, freshwater acidic tolerant species dominating. Relative abundance of planktonic species and geochemical results indicates a period of increased water depth and lake productivity in the early Holocene and a gradual decrease in effective precipitation throughout the Holocene. Results from this study not only support earlier work conducted on Fraser Island using pollen reconstructions but also demonstrate that diatom community diversity has been relatively consistent throughout the Holocene and late Pleistocene with only minor cyclical fluctuation evident. This record is consistent with the few other aquatic palaeoecological records from the Southern Hemisphere sub-tropics. © 2013 Elsevier B.V.
Alimoradzadeh R.,Zanjan University of Medical Sciences |
Assadi A.,Zanjan University of Medical Sciences |
Nasseri S.,Institute for Environmental Research |
Mehrasbi M.R.,Zanjan University of Medical Sciences
Journal of Environmental Health Science and Engineering | Year: 2012
The removal of 4-chlorophenol from aqueous phase continues to be an important environmental issue. In this work, the photochemical oxidation of 4-chlorophenol in aqueous solutions in a batch reactor using ultraviolet irradiation, hydrogen peroxide and nickel oxide was studied. The efficiency of the system was evaluated with respect to reaction time, pH, feed concentration of reactants, catalyst load, light intensity, and the reaction rate constant. The concentrations of 4-chlorophenol and chloride ions were determined by high performance liquid chromatography and ion chromatography, respectively. Pure nanosized nickel oxide was characterized by X-ray diffraction and scanning electron microscopy. The results showed that the optimum conditions (the complete 4-chlorophenol removal (100%) at 60 min) were obtained at a neutral pH, with 0.2 mol/L H2O2, and 0.05 g/L of nickel oxide. However, no pH effects were observed in the range of 4-10. Analytical profiles on 4-chlorophenol transformation were consistent with the best line fit of the first-order kinetics. Moreover, the degradation rate constant increased with both UV light intensity and decreasing initial concentration of 4-chlorophenol. Finally, the results of mineralization and chloride ions studies indicated that dechlorination was better accomplished but more time was required to completely mineralize 4-chlorophenol into water and carbon dioxide. © 2012 Alimoradzadeh et al.
Hadjinicolaou P.,The Cyprus Institute |
Giannakopoulos C.,Institute for Environmental Research |
Zerefos C.,Institute for Environmental Research |
Lange M.A.,The Cyprus Institute |
And 2 more authors.
Regional Environmental Change | Year: 2011
We present climate change projections and apply indices of weather extremes for the Mediterranean island Cyprus using data from regional climate model (RCM) simulations driven by the IPCC A1B scenario within the ENSEMBLES project. Daily time-series of temperature and precipitation were used from six RCMs for a reference period 1976-2000 and for 2026-2050 ('future') for representative locations, applying a performance selection among neighboring model grid-boxes. The annual average temperatures of the model ensemble have a ±1. 5°C bias from the observations (negative for maximum and positive for minimum temperature), and the models underestimate annual precipitation totals by 4-17%. The climatological annual cycles for the observations fall within the 1σ range of the 6-model average, highlighting the strength of using multi-model output. We obtain reasonable agreement between models and observations for the temperature-related indices of extremes for the recent past, while the comparison is less good for the precipitation-related extremes. For the future, the RCM ensemble shows significant warming of 1°C in winter to 2°C in the summer for both maximum and minimum temperatures. Rainfall is projected to decrease by 2-8%, although this is not statistically significant. Our results indicate the shift of the mean climate to a warmer state, with a relatively strong increase in the warm extremes. The precipitation frequency is projected to decrease at the inland Nicosia and at the coastal Limassol, while the mountainous Saittas could experience more frequent 5-15mm/day rainfall. In future, very hot days are expected to increase by more than 2 weeks/year and tropical nights by 1 month/year. The annual number of consecutive dry days shows a statistically significant increase (of 9 days) in Limassol. These projected changes of the Cyprus climate may adversely affect ecosystems and the economy of the island and emphasize the need for adaptation strategies. © 2010 Springer-Verlag.
Sun N.,CAS Institute of Vertebrate Paleontology and Paleoanthropology |
Sun N.,CAS Institute of Earth Environment |
Li X.,CAS Institute of Vertebrate Paleontology and Paleoanthropology |
Li X.,CAS Institute of Earth Environment |
And 4 more authors.
Quaternary International | Year: 2013
Assessing the potential impact of increased temperature needs examination of robust palaeorecords that contain analogues. The fossil charcoal (anthracological) records from the mid-Holocene archaeological sites can provide palaeo-analogues on the impacts of climate change. The Xishanping and Dadiwan sites were continuously developed during the Neolithic Culture in the Tianshui Basin, western Loess Plateau. A total of 24 samples of fossil charcoal were recovered using a floatation method. At least 100 fragments were examined from each sample, and these fragments were identified following standard procedures, and the results were used to reconstruct the vegetation and plant diversity between 5200 and 4300calBP, which was a warm period for the region. The charcoal evidence from the Xishanping and Dadiwan sites confirm that woody plants were widely available, including temperate taxa such as Betula, Ulmus, Quercus, Carpinus, Acer, Corylus and Padus, and typical subtropical taxa such as Bambusoideae, Liquidambar formosana, Castanopsis, Pseudotsuga sinensis, and Eucommia ulmoides. The assemblages of fossil charcoal show that mixed forests of north-subtropical evergreen and deciduous broadleaved trees existed. This is a broader range of woody plants than at present in the Tianshui Basin. This leads to the conclusion that the warmer and increasing monsoon precipitation resulted in a northward shift in the southern vegetation zones. And that the natural botanical diversity between 5200 and 4300calBP was also greater than at present in the Tianshui Basin, western Loess Plateau. © 2013 Elsevier Ltd and INQUA.
Shahsavani A.,Tehran University of Medical Sciences |
Naddafi K.,Tehran University of Medical Sciences |
Naddafi K.,Institute for Environmental Research |
Jafarzade Haghighifard N.,Health Science University |
And 12 more authors.
Journal of Arid Environments | Year: 2012
In this study, PM10, PM2.5, and PM1 concentrations were measured from April through September 2010. These measurements were made every six days and on days with dust events using a Grimm Model 1.177 aerosol spectrometer. Meteorological data were also collected. Overall mean values of 319.6 ± 407.07, 69.5 ± 83.2, and 37.02 ± 34.9 μg/m3 were obtained for PM10, PM2.5, and PM1, respectively, with corresponding maximum values of 5337.6, 910.9, and 495 μg/m3. The presence of the westerly prevailing wind implied that Iraq is the major source of dust events in this area. A total of 72 dust days and 711 dust hours occurred in the study area. The dust events occurred primarily during July. The longest dust event during the study period occurred in July, lasted five days, and had a peak concentration of 2028 μg/m3. These high concentrations produced AQI values of up to 500. A total estimated mortality and morbidity of 1131 and 8157 cases, respectively, can be attributed to these concentrations. The results of this study indicated the importance of dust events in Ahvaz and their possible health impacts. The study also demonstrated the need to design and implement intergovernmental management schemes to effectively mitigate such events. © 2011 .
Woodward C.,University of Queensland |
Shulmeister J.,University of Queensland |
Zawadzki A.,Institute for Environmental Research |
Jacobsen G.,Institute for Environmental Research
Holocene | Year: 2014
Lake sediment records from three lakes in the South Island of New Zealand were examined to determine the effects of human (Māori and European) impacts on the lake catchments during the Late Holocene. Major changes in lake biota occurred in the Early to Middle Holocene (11,000-6000 cal. yr BP), but there were no major changes between c. 6000 cal. yr BP and the time of human impact. Intensive Māori forest clearance occurred here between c.ad 1200 and 1600, which is consistent with other New Zealand records. Catchment erosion and increased sedimentation probably occurred in all of the studied lakes, but the most obvious changes occurred in Lake Clearwater and the Māori Lakes. There was evidence for gravity-induced slumping of the littoral sediments in Lake Clearwater due to increased sediment loading, and the outflow from the Māori Lakes was blocked by a migrating alluvial fan. The erosion of sediment (and nutrients) from the lake catchments led to eutrophication, but increases in lake depth were just as important in two of the lakes. Increased water depth was caused by damming of the Māori lakes outflow by a migrating alluvial fan. Reduced evapotranspiration following deforestation would also have led to increased water yield in lake catchments. European impacts were minor compared with the impacts of Māori deforestation, and all lakes display different levels of recovery towards pre-human impact conditions. Complete recovery is prevented by permanent changes in catchment hydrology and probable internal feedback mechanism such as wind-induced sediment re-suspension in the larger lakes. © The Author(s) 2014.
Kotroni V.,Institute for Environmental Research |
Lagouvardos K.,Institute for Environmental Research |
Lykoudis S.,Institute for Environmental Research
Renewable and Sustainable Energy Reviews | Year: 2014
In the frame of this paper a wind climatology has been built for Greece, based on high resolution model simulations performed for a typical year of wind conditions over the area. The methodology followed includes: (a) the development of a typical wind year, (b) the definition of a modeling strategy and the performance of the appropriate simulations, (c) the verification of the 10-m wind speed simulated by the model against observations, (d) the statistical analysis of the wind simulations for the construction of the wind atlas. The analysis is performed at 50 m and includes gridded wind speeds, the parameters of the respective Weibull distributions, and the potential power production. Finally a discussion on the effect of the topography height and slope on the wind distribution and consequently on the wind potential density is provided. © 2013 Elsevier Ltd. All rights reserved.
Sanayei Y.,Universiti Sains Malaysia |
Chaibakhsh N.,Guilan University |
Chaibakhsh A.,Guilan University |
Pendashteh A.R.,Institute for Environmental Research |
And 2 more authors.
International Journal of Chemical Engineering | Year: 2014
A Wiener-Laguerre model with artificial neural network (ANN) as its nonlinear static part was employed to describe the dynamic behavior of a sequencing batch reactor (SBR) used for the treatment of dye-containing wastewater. The model was developed based on the experimental data obtained from the treatment of an effluent containing a reactive textile azo dye, Cibacron yellow FN-2R, by Sphingomonas paucimobilis bacterium. The influent COD, MLVSS, and reaction time were selected as the process inputs and the effluent COD and BOD as the process outputs. The best possible result for the discrete pole parameter was α = 0.44. In order to adjust the parameters of ANN, the Levenberg-Marquardt (LM) algorithm was employed. The results predicted by the model were compared to the experimental data and showed a high correlation with R 2 > 0.99 and a low mean absolute error (MAE). The results from this study reveal that the developed model is accurate and efficacious in predicting COD and BOD parameters of the dye-containing wastewater treated by SBR. The proposed modeling approach can be applied to other industrial wastewater treatment systems to predict effluent characteristics. © 2014 Yasaman Sanayei et al.