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51.
52.
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   
53.
A selective and sensitive method for the preconcentration, separation, and determination of palladium with flame atomic absorption spectrometry using 4,15‐bis[(4‐methylphenyl)sulfonyl]‐20,21‐dinitro‐2,3,4,5,6,7,9,10,12,13,14,15,16,17‐tetradecahydro‐8,11‐ethano‐1,18,4,8,11,15‐benzodioxa tetraaza cycloicosine (TNACIN) on XAD‐2010 was developed. TNACIN–Pd(II) complex formed acidic aqueous solution (0.075–0.100 M HNO3) was accumulated on XAD‐2010 and then eluted with 1 M HCl in acetone. The effects of some analytical parameters including pH, TNACIN amount, sample volume, eluent type, and concentration, sample flow rate and matrix ions were studied for optimization of the method. Detection limit and precision were calculated for Pd(II). This method was also verified with CRM and internal standard, and satisfactory results were obtained.  相似文献   
54.
An earthquake with a magnitude of 5.7 $(\text{ M}_{\mathrm{L}})$ has struck Simav, Kutahya located in the western part of Turkey on May 19, 2011. The ground motion caused observable damage within 25 km radius from the epicenter. Although the earthquake is moderate, its effects on the structures are serious. This paper presents the observations on seismic damages of reinforced concrete (RC) and masonry structures. Common reasons of damage in RC buildings are: low quality of concrete, detailing mistakes of reinforcement, short column, pounding, overhangs and misconstructed gable and outer infill wall parts. Interesting cases related to these deficiencies are reported. Damages in the masonry buildings are due to lack of connection between orthogonal walls and unsuitable location and dimension of openings. The damages at structures are more noticeable at regions with unfavorable soil conditions like plain regions or foothills. However, on stiffer soils at hilly sides, the damages seem to be more limited and masonry structures are observed to be less affected compared to the RC ones. The damages in RC buildings found to be increasing with story number for light damage states. However, for heavier damage states, 4–5 story buildings are observed to be the most damaged.  相似文献   
55.
The lignite coal researched by this study was subjected to a two‐stage activation process performed in the scope of obtaining active carbon from domestic resources. “Activation” and “carbonization” stages were used in the experiments. The modified lignite was produced by impregnating lignite with KOH and washing the activation product with 15% HCl solution after thermal treatment. Increasing KOH dosage also increased the removal efficiency. The variables investigated in adsorption experiments were contact time, initial concentration, pH, and sorbent dosage. Adsorption kinetics was fitted by using the pseudo‐first‐order equation, pseudo‐second‐order equation, and intra‐particle diffusion. Isotherm modeling was carried out using Langmuir, Freundlich, and Dubinin–Radushkevich equations. Selected target compound in this work is common environmental pollutant in waters. A commonly known effect of chloroform is its carcinogenic effect. Therefore, removal of these compounds from water is considerably important. Chloroform removal of 97% for was achieved by the use of Konya region activated lignite.  相似文献   
56.
Genetic transformation is gaining importance for developing plant types suitable to metal accumulate and/or hyperaccumulate. In this study, the transgenic tobacco plant which transferred the ScMTII gene from Saccharomyces cerevisiae to wild type tobacco cultivar Petite Havana (SR1) was grown on soils with low and high cadmium (Cd) and zinc (Zn) concentrations in a growth chamber for 6 weeks and compared to wild type tobacco for Cd and Zn accumulation. Cadmium and Zn accumulations in the transgenic and wild type tobacco plants were increased with the increasing Cd and Zn concentrations. Unlike Zn, the transgenic plant accumulated significantly higher amount of Cd compared to the wild type control plants. Shoot Cd concentrations of transgenic tobacco in higher Cd dosages reached the above the hyperaccumulation threshold value of 100 mg Cd kg?1 in the dry weight (DW). Transgenic tobacco accumulated 354, 400, 372, and 457 mg Cd kg?1 DW, for 10, 20, 40, and 80 mg Cd kg?1 soil treatments, respectively. These values are 3.5–4.5‐fold higher than that of Cd hyperaccumulation threshold value. With 10 mg kg?1 Cd treatment, the bioconcentration factor (BCF) of transgenic tobacco plants for Cd reached up to 35 in which the threshold value for BCF should be at least 10. Our results showed that the transgenic tobacco may be used as a good Cd hyperaccumulator plant and for phytoextraction of Cd contaminated soils, but not for Zn.  相似文献   
57.
This paper presents a comparison of near-fault and far-fault ground motion effects on geometrically nonlinear earthquake behavior of suspension bridges. Bo?azi?i (The First Bosporus) and Fatih Sultan Mehmet (Second Bosporus) suspension bridges built in Istanbul, Turkey, are selected as numerical examples. Both bridges have almost the same span. While Bo?azi?i Suspension Bridge has inclined hangers, Fatih Sultan Mehmet Suspension Bridge has vertical hangers. Geometric nonlinearity including P-delta effects from self-weight of the bridges is taken into account in the determination of the dynamic behavior of the suspension bridges for near-fault and far-fault ground motions. Near-fault and far-fault strong ground motion records, which have approximately identical peak ground accelerations, of 1999 Chi-Chi, 1999 Kocaeli, and 1979 Imperial Valley earthquakes are selected for the analyses. Displacements and internal forces of the bridges are determined using the finite element method including geometric nonlinearity. The displacements and internal forces obtained from the dynamic analyses of suspension bridges subjected to each fault effect are compared with each other. It is clearly seen that near-fault ground motions are more effective than far-fault ground motion on the displacements and internal forces such as bending moment, shear force and axial forces of the suspension bridges.  相似文献   
58.
Devrek town with increasing population is located in a hillslope area where some landslides exist. Therefore, landslide susceptibility map of the area is required. The purpose of this study was to generate a landslide susceptibility map using a bivariate statistical index and evaluate and compare the results of the statistical analysis conducted with three different approaches in seed cell concept resulting in different data sets in Geographical Information Systems (GIS) based landslide susceptibility mapping applied to the Devrek region. The data sets are created from the seed cells of (a) crowns and flanks, (b) only crowns, and (c) only flanks of the landslides by using ten different causative parameters of the study area. To increase the data dependency of the analysis, all parameter maps are classified into equal frequency classes based directly on the percentile divisions of each corresponding seed cell data set. The resultant maps of the landslide susceptibility analysis indicate that all data sets produce fairly acceptable results. In each data set analysis, elevation, lithology, slope, aspect, and drainage density parameters are found to be the most contributing factors in landslide occurrences. The results of the three data sets are compared using Seed Cell Area Indexes (SCAI). This comparison shows that the crown data set produces the most accurate and successful landslide susceptibility map of the study area.  相似文献   
59.
The oxidation of sulfide minerals generates acidic waters containing high levels of SO4 and Fe. The study area has active Pb?CZn?CCu mining. It is thought that the surface/subsurface/underground sulfide minerals in the region generally contribute to the acidification of groundwater. Low pH values are also responsible for dissolved metals (Al, Fe, Mn, SO4, Pb, Zn) in the groundwater and river. Furthermore, current mining wastes have affected concentrations of trace elements in the water. High Fe and Mn concentrations are generally found in the spring which has acidic and low Eh values, while Al, Fe and Mn concentrations in the acidic waters show notable increases with the maximum values reaching 8,829, 19,084 and 1,708?ppb, respectively. These values exceed the Turkish drinking water standard of 200, 200 and 50?ppb, respectively.  相似文献   
60.
This work describes the potential usability of neutralized red mud for the removal of organochlorine pesticides (OCPs) from aqueous solutions. After examination on the adsorption capability of neutralized red mud for all studied OCPs, the experiments were performed by employing aldrin as a model compound. The effect of several parameters, such as contact time, pH of the solution, initial aldrin concentration, and dosage of the adsorbent was evaluated by batch experiments. The determination of OCPs was carried out using traditional liquid–liquid extraction followed by a GC coupled with µ‐electron capture detector (GC‐µECD). The results showed that adsorption equilibrium time depended upon the initial aldrin concentration and adsorption followed the second‐order kinetic model. Kinetic study also indicated that the film diffusion mechanism was a main rate control mechanism. The removal was explained by considering the electrostatic interactions between metal oxides surface of the neutralized red mud and inductively charged centers (negative charge (d?) of chlorine atoms and positive charge (d+) of π‐cloud aromatic ring) of the aldrin molecules. In comparison to the Langmuir isotherm model, the Freundlich model better represented the adsorption data. The neutralized red mud was also succesfully employed for the removal of OCPs from real water samples, including tap water and surface (lake) water, fortified with studied OCPs.  相似文献   
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