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61.
The De?irmendere and Galyan (De?irmendere tributary) Rivers that discharge their water into the Black Sea are important watersheds in the northeastern part of Turkey. Water quality parameters were sampled from 1997 through 2001 for each year at five sites (three for Galyan, two for Degirmendere) along 29 and 42 km gradients, respectively covering all seasons. Surface water was collected from the sites and analyzed for temperature, total alkaline (MAAL), total dissolved solids (TDS), dissolved oxygen (DO), pH, conductivity (EC), nitrate (NO3), nitrite (NO2), total hardness (TH), phenolphthalein alkalinities (PAL) and organic matter (PV). Seasonal changes of water quality were analyzed statistically for both Rivers and evaluated according to the TS 266, EU and WHO standards. The analysis of variance results showed that Ca, Mg, MAL, NO3, pH, TDS and TH parameters of the De?irmendere River and Ca, DO, EC, MAL, NO3, pH and TH parameters of the Galyan River showed seasonal differences (p<0.05). The maximum values of the water pollution parameters for the two Rivers were below the threshold values throughout the study period. When both Rivers were compared, the mean values of the pollution parameters of the Degirmendere River were higher than those of the Galyan River and very close the limits. The results indicate that both Rivers can be used for the production of potable water during all seasons but only with an advanced treatment in the De?irmendere and a moderate treatment in the Galyan River, and for indirect and non-contact recreational activities.  相似文献   
62.
In this study, EPS produced by five Bacillus spp. strains was determined. The only one strain (B. sphaericus 7055) was selected due to its high EPS production and it was investigated by growing this strain in LB broth medium containing various carbon sources. The highest EPS production of this strain was found in medium containing fructose. However, the effect of different concentrations of fructose and molasses on EPS production by the strain was studied. The maximum EPS yield of the strain 7055 was recorded with 2.5% (w/v) fructose, also the highest EPS production was found in 2.5% (w/v) molasses. The strain 7055 was found to contain (98.6%) galactose and (1.4%) glucuronic acid in control medium whereas the composition of the strain 7055 (2.5% (w/v) fructose) was found to be (99.9%) neutral sugar and (0.1%) Glucuronic acid while the strain 7055 (2.5% (w/v) molasses) was found to contain (65.9%), neutral sugars and (34.1%) glucuronic acid.  相似文献   
63.
In this study, the influence of infection by pine mistletoe (Viscum album L. subsp. austriacum (Wiesb.) Volmann) on the radial growth of crimean pine (Pinus nigra Amold) in Turkey was investigated. We built local residual tree-ring-width chronologies using dendrochronogical techniques. Tree ring chronologies of uninfected (control) crimean pine were used to estimate potential radial growth characteristics in the "infected" crimean pine (light, moderate and severe infection groups). In 2005, increment cores were collected from 26 infected and 19 control dominant or co-dominant trees and annual radial growth indices from 1930-2005 were calculated for each infection group in a 14 point sampling. We compared radial growth in the uninfected trees with mean regional chronology. We found a strong decrease in radial growth in during the 1998-2005 period. The periodic average radial growth reduction (in %) from 1998 to 2005, respectively, were 0 for control, 26 for light, 39 for moderate and 63 for severe infection groups. It can be especially concluded that a severe degree of pine mistletoe attack has a negative effect on radial growth of the infected crimean pine trees.  相似文献   
64.
Integrated iron and steel plants generate large amounts of metallurgical slag, which usually contains some quantity of metals or mixtures of oxides that could be treated to be recycled in various applications. The conventional method for disposal of slags is dumping. However, it is possible to process the slags to be used in the production of metallic iron, or as an additive in cement making. In this study, a basic oxygen furnace (BOF) steelwork slag obtained from the Kardemir integrated iron and steel works, Karabuk, Turkey is used. A drum magnetic separator system with pre-engineered crucial processing parameters of drum revolution speed, drum radius, drum flesh thickness, and magnitude of the magnetic field applied is utilized, as these parameters have a competing influence on the results. Subsequently, the effects of slag grain size and the drum-blade gap are investigated in the separation efficiency of magnetic grains. It is found that collection of magnetic grains is improved by decreasing the grain size of slags and moreover, the collection of magnetic grains fraction is increased with an increase in the gap between the blades and drum.  相似文献   
65.
This study prepared antibacterial nanocomposite films for food packaging from Montmorillonite, which was modified by quaternary ammonium salts such as cetyltrimethylammonium bromide (CT), hexadecyl-tributyl phosphonium bromide (HD) and corn starch (CS). After this, it determined the antimicrobial activity of CS nanofilms against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. Dispersion of silicate layers and starch nanocomposite films was analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), and the results indicated that presence of quaternary ammonium salts enhanced clay dispersion, and the starch films incorporated with quaternary ammonium salts would provide potential use in food packaging as nanostructural materials. The nanofilms that were obtained based on the results of the antibacterial analysis were confirmed to have much stronger antibacterial properties than those in similar studies in the literature.  相似文献   
66.
Seasonal variation of the concentrations of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were measured by ICP-AES in the water and sediment from the Saricay Stream, Geyik Dam and Ortakoy Well in the same basin. Comparisons between trace metal concentrations in water and sediment in three sources (Stream, Dam and Well) were made. The concentrations of a large number of trace metals in the water and sediment were generally higher in the Stream than in the Well and Dam, particularly in summer. Trace metal concentration ranges in sediments of the Saricay Stream and its sources showed very wide ranges (as mass ratio): Co: 5–476 μg g−1, Cr: 15–1308 μg g−1, Cu: 7–128 μg g−1, Fe: 1120–13210 μg g−1, Mn: 150–2613 μg g−1, Ni: 102–390 μg g−1, Pb: 0.7–31.3 μg g−1 and Zn: 18–304 μg g−1, whereas Cd was not detected. Trace metal concentration ranges found in waters were: Co: 9.5–20.7 μg L−1, Cr: 20.3–284 μg L−1, Cu: 170–840 μg L−1, Fe: 176–1830 μg L−1, Mn: 29.3–387 μg L−1, and Ni: 4.3–21.9 μg L−1. Among the trace metals studied, Cd and Zn in two seasons and Pb in winter were usually not detected or in the recommended levels. In addition, Cd was not detected in the sediment during the winter season. The analysis of variance (one-way ANOVA) and correlation matrix was employed for the sediment and water samples of the two field surveys (summer and winter) comparison. The three sources showed differences in metal contents. The metal levels in sediments displayed marked seasonal and regional variations, which were attributed to anthropogenic influences and natural processes. In the Saricay Stream, high values of metals during the dry season showed an anthropological effect from small industry firms, e.g.: an olive mill and a dairy farm or water dilution during summer seasons. Finally, the pollution in this basin probably originated from small industrial, low quality coal-burned thermal power plants, and particularly agricultural and domestic waste discharges.  相似文献   
67.
Waste water pollution in industrial areas is one of the most important environmental problems. Heavy metal pollution, especially chromium species in waste water sources from tannery affects our lives. Kocabas Stream is located in south-west Marmara region and Biga town is positioned in the sub basin on the stream. This water source functions as the water for irrigation in agriculture, drinking water for animals and for human use. Thus, this study is of great importance. Waste water pollution can affect all ecosystems and human health by directly or indirectly as in food chain. The concentration of heavy metals (Pb, Cd, Cu, Zn and Cr) were pre-analysed by ICP-AES method in water samples taken from sub-basin of Kocabas stream. In the results of these analyses, concentrations of the metals except chromium were founded at the limit value. But the total concentration of the Cr was found at high levels of between 0.0082 +/- 0.0001 and 5.7231 +/- 0.0921 mg l(-1) over the limit value (0.05 mg l(-1); WHO, EPA, TSE 266 and inland water quality classification) at sampling points very close to tannery factories. Also physicochemical and microbiological parameters of Kocabas Stream were determined. The effects of the experimental results on environment were investigated.  相似文献   
68.
Kemaliye (Erzincan/Turkey) is the member of European Association of Historic Towns and Regions. The aim of this study was to reveal the visual richness of the town; to identify the relationship between landscape spatial pattern and visual quality of the landscape and to offer some suggestions for the future planning in regarding to these visual beauties. The visual quality assessment method was used in this study. The results of the study revealed three landscape types that have the highest visual quality. Among those, the highest one is urban scenery 3 (US3; VQP = 5.9400), the second is geological structure scenery 5 (GSS 5; VQP = 5.9200) and the third natural scenery 3 (NS3; VQP = 5.9133). Visual quality assessment showed that urban pattern, geological structure and natural resources of the region also have visual value. The relationships between landscape spatial pattern and visual quality of landscape indicated that certain characteristics of landscape affected the quality. For instance, as the texture level decreased in natural landscapes and as the green areas increased in geological structure, visual preferences ratio increased. Some suggestions were also made regarding the visual resources use in the region.  相似文献   
69.
The trace element contents of seven kinds of herbal plants and spice samples retailed in local markets in Kayseri-Turkey were determined by flame atomic absorption spectrometry after digestion with HNO3/H2O2 mixture. The concentration ranges for the studied elements were found as 6.0–15.2, 0–32.2, 80.0–324.8, 8.1–386.3, and 13.1–36.2 μg/g for copper, nickel, iron, manganese, and zinc, respectively. The levels of cobalt, lead, and chromium ions in all the investigated samples were found to be below the detection limit of flame atomic absorption spectrometry. The results found in the present work were compared with values in the literature.  相似文献   
70.
Underground mining activities may potentially play a role on the initiation and reactivation of the slope movements. However, an adequate attention has not yet been paid to these problems; in this study, the possible influence of present and former mining activities on the selected set of model slope deformations in the Ostrava-Karviná Coalfield (Opliji, Repiste and Orlova Lazy District) was analysed and a methodology for their observation for application to similar conditions and influence was described. Isocatabase maps, terrain deformation parameters calculated for the point lying on the slope deformation surface, length measurement by zone extensometer and dilatometer measurement in cracks was also provided for evaluation of the underground mining impact. It was found that inclinations of both boreholes were evidence of underground mining impact, and localization of inclinometer measurement on boreholes in the active part as well as in the near vicinity was very important as an important result of this study. Analysis of underground mining activity influence on model localities in relation to performed mining operations, subsidence and other influences on the ground surface was also determined. Thus, the study will contribute to a more objective knowledge of these problems of interest for the professional public and also for the state administration to solve problems associated with the utilisation and settlement of such affected areas.  相似文献   
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