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S. Tadjiki H. N. Erten J. Erten 《Journal of Radioanalytical and Nuclear Chemistry》1995,199(4):309-316
Instrumental neutron activation analysis has been used to determine 15 trace elements in twelve blood serum samples taken from healthy students at Bilkent University in Ankara. The method allowed the determination of Sc, Cr, Mn, Fe, Co, Zn, Se, Rb, Cs, Ce, Eu, Tb, Hf, Ta and Hg, which occur at the g.ml–1 to ng.ml–1 levels. There are no values reported for Tb, Hf, Ce, Eu and Ta before. The other results are compared with the values reported in the literature. Most are in the range of the reported values except for Fe, Zn, Se and Cs. 相似文献
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The210Pb and137Cs profiles of sediment cores from two locations in southern Spain, three locations in southern Turkey and two locations in northern Cyprus were determined by direct -ray spectroscopy. Sedimentation rates were derived for all locations using the210Pb data. The rates range from 1.39±0.12 cm · y–1 (0.50±0.04 g · cm–2 · y–1) to 0.08±0.01 cm · y–1 (0.039±0.003 g · cm–2 · y–1). Except for one core, the137Cs profiles were also used to compute sedimentation rates. The results are in good agreement with those of210Pb values. The results of the Constant Initial Concenration and Constant Rate of Supply dating models are in good agreement with each other. The flux of unsupported210Pb varies between 0.11±0.03 to 0.74±0.01 pCi · cm–2. The average depositional flux was found to be considerably lower for cores from the Eastern Mediterranean. 相似文献
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Soheyl Tadjiki Shoeleh Assemi Cassandra E. Deering John M. Veranth Jan D. Miller 《Journal of nanoparticle research》2009,11(4):981-988
A rapid, high-resolution methodology for characterization, separation, and quantification of unlabeled inorganic nanoparticles
extracted from biological media, based on sedimentation field-flow fractionation and light scattering detection is presented.
Silica nanoparticles were added to either human endothelial cell lysate or rat lung tissue homogenate and incubated. The nanoparticles
were extracted by acid digestion and then separated and characterized by sedimentation field-flow fractionation. Fractions
collected at the peak maxima were analyzed by transmission electron microscopy (TEM) to verify the size and shape of the isolated
nanoparticles. Using the linear relationship between the particle number and the area under the fractogram, the recoveries
of particles from the tissue homogenate and cell lysate were calculated as 25% and 79%, respectively. The presented methodology
facilitates detection, separation, size characterization, and quantification of inorganic nanoparticles in biological samples,
within one experimental run. 相似文献
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The efficient use of cellulose sulfuric acid as a heterogeneous catalyst promotes three-component, one-pot Mannich reaction of various ketones, aromatic aldehydes, and aromatic amines in ethanol to make the corresponding β-amino ketones with high stereoselectivity in favor of the anti-isomer. This protocol has several advantages such as good yield, mild reaction conditions, no environmental hazards, and simple workup procedure. 相似文献
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Ronald Beckett Deirdre Murphy Soheyl Tadjiki David J. Chittleborough J. Calvin Giddings 《Colloids and surfaces. A, Physicochemical and engineering aspects》1997,120(1-3):17-26
Sedimentation field-flow fractionation (SdFFF) can be used to prepare fractions of very narrow mass range for electron microscopic (EM) analysis. Assuming the particle density is the same for all particles within that fraction the equivalent spherical diameter for the particles can be calculated from SdFFF theory. Integration of the micrograph image of each particle yields an area measurement which, when used in conjunction with the equivalent spherical particle diameter (from SdFFF), provides information about the particle thickness and aspect ratio. Thus SdFFF-SEM can be used to provide detailed information about clay morphology across the particle size distribution of the sample. Three clay minerals have been studied using the methodologies outlined in this paper. The aspect ratio for the Purvis School Mine kaolinite ranged from 2.8–5.9, for RM30 illite from 11.3–24.3, and for Muloorina illite from 3.1–4.3. 相似文献
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