Browsing by Publisher "Springer Singapore"

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    Annual effective dose values from 137Cs activity concentrations in soils of Manisa, Turkey
    (Springer Singapore, 2018) Çam Kaynar S.
    In this study, the activity concentrations of the fallout radionuclide 137Cs in 150 soil samples collected from 13 districts of Manisa Province were determined using a gamma ray spectrometer with a NaI(Tl) detector. The health risks to people resulting from external exposure were evaluated by estimating the outdoor absorbed gamma dose rate and annual effective dose rate (outdoor and indoor). The activity concentration of 137Cs varied from 3.6 ± 2.0 to 124.1 ± 11.0 Bq kg−1, with an average value of 43.3 Bq kg−1. The average values of the outdoor absorbed gamma dose rate and annual effective dose (outdoor plus indoor) were found to be 1.3 nGy h−1, and 8.0 µSv y−1, (6.38 + 1.59 µSv y−1), respectively. The results were compared with internationally recommended values. © 2018, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Nature Singapore Pte Ltd.
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    Sorption of uranium(VI) from aqueous solutions by DEEA organo-volcanic: isotherms, kinetic and thermodynamic studies
    (Springer Singapore, 2018) Kaynar Ü.H.; Hiçsönmez Ü.; Çam Kaynar S.; Koçak S.
    The sorption of the uranium(VI) ions from aqueous solutions by diethylethanolammonium organo-volcanics (Kula-TURKEY) was investigated under different experimental conditions. DEEA was used to modify the surface of basaltic volcanics. The characteristic of basaltic volcanic was analyzed by XRF, SEM–EDS, FTIR, and XRD. The BET surface areas of unmodified volcanics and DEEA-modified volcanics were found as 2.265 and 3.689 m2/g, respectively. The volcanic samples were treated by using different concentrations of DEEA. The adsorption of U(VI) on natural and modified volcanics was examined as a function of the contact time, initial pH of the solution, initial U(VI) concentration, and temperature. Langmuir, Freundlich, and D–R adsorption isotherms were used to describe the adsorption. While examining the adsorption percentage and distribution coefficient, these values for unmodified volcanics were found to be 25% ± 0.76 and 10.08 mL/g, while the values for the DEEA-modified volcanics were 88% ± 1.04 and 220 mL/g, respectively. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data. In this study, it can be seen that the adsorption process is suitable for the pseudo-second-order kinetic model. Various thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were calculated with the thermodynamic distribution coefficients obtained at different temperatures. The sorption process was a chemical adsorption process. The results indicated that the processes are spontaneous and endothermic. © 2018, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Nature Singapore Pte Ltd.
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    Non-mycorrhizal fungal spectrum of root communities
    (Springer Singapore, 2019) Özkale E.
    The root-soil interface known as rhizosphere is a dynamic environment which is physically, chemically and biologically different from the bulk of soil populations, a microcosm where microorganisms, plant roots and soil constituents interact and develop. The rhizosphere therefore is the zone of influence of plant roots on the associated microbiota and soil components characterized by an altered microbial diversity with increased activity and number of microorganisms. Over 90% of plant species/roots are colonized by mycorrhizal fungi but also by various clades of endophytic fungi. Although many of these fungi are regarded as commensalistic symbionts and the function of the root-associated fungi is not exactly known, recent studies have shown that they can benefit their hosts by mineralizing soil nutrients in the rhizosphere or protecting hosts from soil pathogens. Besides the sharing root with associated fungi could facilitate the coexistence of plant species, studies clarify how diverse clades of root-associated fungi shared within a plant community are essential to plant community dynamics and stability. Although arbuscular mycorrhizal fungi are one of the most important components of the soil ecosystem, the roots are also colonized by diverse non-mycorrhizal fungal species which are represented in much greater numbers than mycorrhizal fungi. They are mostly found without causing any symptoms of disease. They may promote the growth of plants such as orchids by mobilizing soil nutrients in the rhizosphere. Influence on amounts or changes of secondary metabolites was also indicated. In general they are thought to be a resource for bioactive compounds that protect the host from soil pathogens. © Springer Nature Singapore Pte Ltd. 2019.