排序方式: 共有97条查询结果,搜索用时 15 毫秒
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For the determination of vanadium in biological materials by flame AAS an enrichment is described which comprises chelation with oxine and adsorption on activated carbon: The relative standard deviation for 10 g V/L was found to be 6% (n=15).Dedicated to Professor Dr. Dieter Klockow on the occasion of his 60th birthday 相似文献
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Determination of Cr(VI) and Cr(III) by Using Activated Carbon-Atomic Absorption Spectrometry 总被引:1,自引:0,他引:1
M. Yaman 《Journal of Analytical Chemistry》2003,58(5):456-460
A method for the separation and preconcentration of Cr(III) and Cr(VI) on activated carbon in presence of diethyldithiocarbamate as a complexing reagent was optimized. The method makes it possible to achieve 200- to 500-fold Cr(VI) concentrating depending on the initial volume of the solution to be analysed and the final volume eluted. The Cr(VI) concentration in the background solution determined with RSD 30% was equal to 1.5 g L. The limit of Cr(VI) determination was equal to 0.9 g L. 相似文献
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Irem Dashan Melisa Elverici Demet Karaca Balta Binnur Aydogan Temel Gokhan Temel 《Journal of polymer science. Part A, Polymer chemistry》2019,57(12):1275-1282
Light‐responsive crosslinked structures were prepared by a straightforward quaternization strategy using chloride functional polystyrene copolymers and commercially available Michler's ketone with varying feed ratios. Resulting organogels demonstrated excellent solvent absorption and their swelling characteristics were altered by UV‐light irradiation. According to scanning electron microscope images, UV‐illuminated samples showed an obvious photodecomposition, which enhanced their solvent uptake capacity with increase of UV exposure. Additionally, release behavior of eosin Y as a model compound was determined by UV–vis and fluorescence spectrometers. Achieved photoactive gels were also employed as the reusable heterogeneous initiators for photoinduced free‐radical polymerization of methyl methacrylate. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1275–1282 相似文献
4.
An inverse coefficient problem for a quasilinear parabolic equation with periodic boundary and integral overdetermination condition
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In this paper, the inverse problem of finding the time‐dependent coefficient of heat capacity together with the solution periodic boundary and integral overdetermination conditions is considered. Under some natural regularity and consistency conditions on the input data, the existence, uniqueness, and continuous dependence upon the data of the solution are shown. Some considerations on the numerical solution for this inverse problem are presented with an example. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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This paper describes a novel approach to detect Cd(II) using the combination of the differential pulse anodic stripping voltammetry and magnetic nanoparticle based dispersive solid phase microextraction as an efficient, green and accurate method. Currents of Cd(II) increased linearly in the range from 75 to 2000 ng L−1 Cd(II) with a detection limit of 21.6 ng L−1. The RSD values of 2.6 and 6.0 % for 1.00 and 0.10 μg L−1 respectively showed that proposed method has an acceptable repeatability. Recovery values between 92.3 and 98.6 % showed that this approach can be successfully used for determination of Cd(II) in water samples. 相似文献
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Mehmet Yaman 《光谱学与光谱分析》2013,32(5):1331-1337
The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus libani and Cupressus arizonica together with soil samples were collected from different points depending on traffic intensity,nearness the city center and cement factory as well as control location during different months of the year.Flame atomic absorption spectrophotometer(FAAS) was used for measurement of the metals in clear digests after the dry ashing method.Copper and Co concentrations were in the ranges from 1.3to 2.6mg.kg-1 and相似文献
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Hande Yaman 《Mathematical Programming》2006,106(2):365-390
We consider the vehicle routing problem where one can choose among vehicles with different costs and capacities to serve the
trips. We develop six different formulations: the first four based on Miller-Tucker-Zemlin constraints and the last two based
on flows. We compare the linear programming bounds of these formulations. We derive valid inequalities and lift some of the
constraints to improve the lower bounds. We generalize and strengthen subtour elimination and generalized large multistar
inequalities. 相似文献
10.
Mustafa İlhan Ayhan Mergen Cevat Sarıoğlu Cemalettin Yaman 《Journal of Thermal Analysis and Calorimetry》2017,128(2):707-711
Heat capacity measurements of barium tantalate (BaTa2O6) were carried out by using a differential scanning calorimeter at temperatures between 323 and 1323 K. From the heat capacity values of BaTa2O6, other thermodynamic functions (enthalpy and entropy increments) were derived between 298.15 and 1323 K. The C p,m (298.15) value of BaTa2O6 was computed as 184.857 J mol?1 K?1. Moreover, fitted heat capacities exhibited good agreement with Neumann–Kopp rule at the temperatures between 298.15 and 1300 K. 相似文献