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Sorption behavior of Lanaset Red (LR) G on lentil straw (LS) was studied as a function of particle size, adsorbent dose, initial pH value, initial dye concentration, and contact time. Sorption kinetics data was well described by logistic model. Modified logistic equation can be used to explain effects of initial dye concentrations and contact time on the sorption of LR G with high R2 value. Freundlich model was found to be excellent in representing the equilibrium data. Thermodynamic parameters like free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated by the use of Langmuir constant. Thermodynamic data showed that the sorption processes were spontaneous and endothermic in nature. Desorption process suggested that strong binding and weak interactions could be formed between adsorbent surface and dye molecules. Results revealed that LS has a remarkable potential for the sorption of LR G. 相似文献
23.
In this study, the adsorption of reactive red 120 (RR 120) on pistachio husk, and the modeling of the adsorption was investigated. Characterization of the pistachio husk was confirmed by Fourier transform infrared spectroscopy. The pHzpc of pistachio husk was found to be pH 8.5. Increasing the initial pH value decreased (p < 0.01) the amount of dye adsorbed. However, increasing the initial dye concentration from 50 to 900 mg/L at pH 1 increased (p < 0.01) the equilibrium dye uptake from 20.83 to 182.10 mg/g. Results indicated that this adsorbent had great potential for the removal of RR 120 dye. The logistic model was found to be the most suitable of the kinetic and equilibrium models tested to describe the adsorption of the dye. The parameters determined from the logistic model were well correlated with the initial dye concentration, and were seen to increase with the increasing initial dye concentration, but this was not observed from pseudo‐second order kinetics. 相似文献
24.
Phthalates are considered priority pollutants because of their potential adverse effects on ecosystems and human health. The objectives of this study were to determine the occurrence of five phthalates (DMP, DEP, DBP, BBP, and DEHP) in sewage sludge and to determine the seasonal variability of these contaminants at three (Bahçe?ehir, Pa?aköy, and Tuzla) full‐scale municipal and domestic wastewater treatment plants (WWTP) in Istanbul, Turkey. Mass balance was also calculated for DEHP at Tuzla WWTP sludge treatment units. DMP, DEP, DBP, BBP, and DEHP concentrations in sewage sludge ranged from 1.4 to 2.7 mg/kg dry weight (dw), 1.1 to 2.8, 0.6 to 4.6, 2.8 to 6.2, 18 to 490 mg/kg dw, respectively. Phthalate concentrations from the Bahçe?ehir and Pa?aköy WWTPs met the limit (100 mg/kg dw) of Turkey national sludge regulation and the Europe Union draft of sludge directive for land application, whereas phthalate concentrations from Tuzla WWTP exceeded the maximum permissible concentration. Phthalate concentrations did not show seasonal variations for Bahçe?ehir and Pa?aköy WWTPs, which receive mainly household wastewater while some fluctuations were observed DEP, DBP, and DEHP at Tuzla WWTP which has a lot of industrial wastewater contribution. The mass balance showed that approximately 17% of DEHP in the primary and secondary sludge was removed by anaerobic digestion, while 43% returned back to the beginning of the WWTP and 40% remained in the dewatered sludge. This study suggests that phthalates in sludge from WWTPs with industrial wastewater contribution may limit the use of sludge for land application. 相似文献
25.
In this study, it was aimed to characterize temporal variations of air pollutants for determining contribution to pollution episodes and to obtain correlations between these pollutants. With this aim we used data analysis for measured sulfur dioxide (SO2), particulate matter (PM, black fume and PM10), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO), methane (CH4), and non‐methane hydrocarbons (NMHC) recorded in Kocaeli, one of the most industrilizated cities of Turkey. Pollutant concentrations were the results of continuous and semi‐automatic measurements. Semi‐automatic measurements of SO2 and PM (black fume) were enclosing period from 1987 to 2008 whereas continuous monitoring of all pollutants included years of 2007–2009. In the first stage of the study daily, monthly, annual, and seasonal variations of pollution were researched. Annual average concentrations were compared with limits set by Air Quality Protection Regulation (AQPR), Air Quality Evaluation and Management Regulation (AQEMR), World Health Organization (WHO), European Union (EU), and National Ambient Air Quality Standards (USEPA). In the following stage relationships between pollutants such as NO2–O3, NOx–CO, NOx–NMHC, and NOx–SO2 were investigated and correlation coefficients were determined as 0.87, 0.56, 0.51, and 0.69, respectively. R2 values of regression models developed from these correlations were 0.78, 0.56, 0.34, and 0.72, respectively. Vehicle density of the traffic was evaluated with NOx–O3 emissions and decrease was seen in NOx emissions due to decreasing vehicle density at weekends whereas O3 concentrations increased. These correlations enable prediction of the parameters that cannot be measured which is important for providing improvement in early warning systems. 相似文献
26.
This study compares the thermal bioclimatic conditions recorded at Bursa (100 m) and Uluda? (1878 m) meteorological stations at 7:00, 14:00 and 21:00 LST (local standard time) between 1975 and 2006, by using the physiologically equivalent temperature (PET), which is calculated from meteorological parameters. The effects of elevation-dependent environmental and atmospheric conditions on thermal perception (i.e., PET) values were analyzed and assessed. The analysis showed that the mean annual difference between PET values in Bursa and Uluda? was 12 ºC. The difference was lower in winter (9 ºC PET) and higher in summer (15 ºC PET). The highest difference between PET values occurred in the afternoon (16 ºC PET) and the lowest difference occurred in the morning (8.4 ºC PET). The differences occur as a result of high altitude and higher surface albedo due to snowfall, which leads to lower PET values and thus to less comfortable thermal conditions. The mean PET values of Bursa and Uluda? decrease 0.67 ºC every 100 m. 相似文献
27.
The Late Cretaceous ükapili Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by Neogene ignimbrites in the Ni de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The ükapili Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The ükapili Granitoid has calcalkaline and peraluminous (A/CNK= 1.0-1.3) geochemical characteristics. It is characterized by high LILE/HFSE and LREE/HREE ratios ((La/Lu) N = 3-33), and has negative Ba, Ta, Nb and Eu anomalies, resembling those of collision granitoids. The ükapili Granitoid has relatively high 87Sr/86Sr (i) ratios (0.711189-0.716061) and low εNd (t) values (-5.13 to -7.13), confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs (K, Rb) and Th, and have negative Ta, Nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the ükapili granitoid is H-(hybrid) type, post-collision granitoid developed by mixing/mingling processes between crustal melts and mantle-derived mafic magmas. 相似文献
28.
Samir Belabbès Mustapha Meghraoui Ziyadin Çakir Youcef Bouhadad 《Journal of Seismology》2009,13(4):421-432
We study the surface deformation associated with the 22 December 1999 earthquake, a moderate sized but damaging event at Ain
Temouchent (northwestern Algeria) using Interferometric Satellite Aperture Radar images (InSAR). The mainshock focal mechanism
solution indicates reverse faulting with a NE–SW trending rupture comparable to other major seismic events of this section
of the Africa–Eurasia plate boundary. Previously, the earthquake fault parameters were, however, poorly known because no aftershocks
were precisely determined and no coseismic surface ruptures were observed in the field. Using a pair of ERS data with small
baseline and short temporal separation in the ascending orbit we obtained an interferogram that shows the coseismic surface
displacement field despite poor coherence. The interferogram measures four fringes and displays an ellipse-shaped lobe with
∼11 cm peak line-of-sight displacement. The elastic modeling using a boundary element method (Poly3Dinv) indicate coseismic
slip reaching up to 1 m at 5 km depth on the N 57° E trending, dipping 32° NW Tafna thrust fault. The geodetic estimate of
seismic moment is 4.7 × 1017 N m. (Mw 5.7) in is good agreement with seismological results. The elliptical shape of the surface displacement field coincides
with the NE–SW trending Berdani fault-related fold. The consistency between the geological observations and InSAR solution
shed light on the precise earthquake location and related Tafna fault parameters. 相似文献
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