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191.
In this article a new coated platinum Cu2+ ion selective electrode based on 2-((2-(2-(2-(2-hydroxy-5-methoxybenzylideneamino)phenyl)disufanyl)phenylimino) methyl)-4-methoxyphenol Schiff base (L1) as a new ionophore is described. This sensor has a wide linear range of concentration (1.2 × 10−7-1.0 × 10−1 mol L−1) and a low detection limit of 9.8 × 10−8 mol L−1of Cu(NO3)2. It has a Nernstian response with slope of 29.54 ± 1.62 mV decade−1 and it is applicable in the pH range of 4.0-6.0 without any divergence in potentioal. The coated electrode has a short response time of approximately 9 s and is stable at least for 3.5 months. The electrode shows a good selectivity for Cu2+ ion toward a wide variety of metal ions. The proposed sensor was successfully applied for the determination of Cu2+ ion in different real and environmental samples and as indicator electrode for potentiometric titration of Cu2+ ion with EDTA. 相似文献
192.
M. Babamoradi M. Heidari Saani A. Ranjbar M. A. Vesaghi Y. Kawazoe 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,84(1):1-9
Using a generalized Hubbard Hamiltonian, many-electron wavefunctions of negatively
charged (NV−) and neutral nitrogen-vacancy (NV0) centers in diamond
were calculated. We report the effect of symmetric relaxation of surrounding atoms on the
spin density, calculated from the many electron wavefunctions in the ground and excited
states. We evaluated the error, that, arises in estimation of spin density when lattice
relaxation effect is neglected in Electron Paramagnetic Resonance experiment and showed
that the ground state spin density distribution is accessible in outward relaxations. The
computed oscillator strengths give a higher efficiency for the 1.945 eV photoluminescence
(PL) line of NV− with respect to 2.156 eV PL line of NV0 which
agrees well with experiment. This result is explained based on the largest the ground
state spin among available values for the NV− with respect to NV0.
The transition probability between degenerate ground and excited states slightly depends
on the S
z
value. Finally, we report on the
electronic configurations which contribute to the ground and excited states and discuss
the population variation of electronic configurations with relaxation. 相似文献
193.
A rapid and efficient one-pot method for the synthesis of 4,6-diarylpyrimidin-2(1H)-ones and related heterocycles is described. The condensation of acetophenone derivatives, aldehydes and urea in the presence of sulfamic acid was employed to synthesize a variety of pyrimidinones in moderate to excellent yields. The scope and limitations of this method are described. 相似文献
194.
Faez Feyzi Jafar Soleymani Siavoush Dastmalchi Fatemeh Ranjbar Abolghasem Jouyban 《Journal of separation science》2023,46(14):2201028
A graphene oxide-based aerogel was synthesized and applied to the extraction and the determinations with the high-performance liquid chromatography-ultraviolet detector. After the characterization of the produced graphene-aerogel, it was utilized as a dispersive solid-phase extraction sorbent for risperidone extraction from plasma samples. Aerogels are materials with a large surface area-to-mass ratio and plenty of core with functional groups which can easily attach to the analytes to extract them to the second phase. The suggested method determined risperidone in plasma samples in the wide dynamic range from 20 ng/ml to 3 μg/ml. The limits of detection and quantification of the developed method were calculated as 2.4 and 8.2 ng/ml, respectively. As a novel feature, the developed method has no need to precipitate plasma proteins, improving the analytical performance of the analysis. Also, for the first time, the produced materials were utilized for the extraction of risperidone from the plasma samples. The obtained results revealed that the developed approach could be employed as an accurate method for the quantification of risperidone in real plasma samples. 相似文献