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101.
A innovative switchable polarity solvent,based on 1,8‐diazabicyclo‐[5.4.0]‐ undec‐7‐ene and decanol was prepared for enrichment of aluminum in biological sample prior to analysis by flame atomic absorption spectrometry
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A novel switchable solvent (SS) extraction methodology has been used for the enrichment of aluminium (Al) in acid‐digested blood samples of patients with neurological disorders before proceeding to flame atomic absorption spectrometry. 1,8‐Diazabicyclo[5.4.0]undec‐7‐ene and decanol in combination made a SS which reversibly changes from hydrophobic (nonpolar) to hydrophilic (polar) according to switch‐on and switch‐off phenomena in aqueous medium by exposure to anti‐solvent trigger (CO2). The SS polar micro‐emulsion was switched on by bubbling CO2, and switched off by heating from 40 to 70°C with exposure to N2 gas. The changes obtained in the structure and physical properties of the SS due to switching from lower polarity to higher polarity were investigated using Fourier transform infrared spectroscopic analysis. The SS was effectively analysed as an extractive medium for hydrophobic chelate of Al with 3,5,7,2,4‐pentahydroxyflavone (morin) and extracted in SS. Then hydrophobic enriched Al‐morin‐SS was treated with 1.0 M HNO3 and CO2 purging at various time intervals, switch to a miscible polar hydrophilic monophase state. The SS was easily recycled up to six times for further enrichment process. For the developed method, various parameters were optimized such as pH, volume of chelating reagent, CO2 purging time and pressure, and rate of heating. Under favourable conditions, enhancement factor and limit of detection were observed as 25 and 0.47 μg l?1, respectively, for 10 ml of samples/standards solution. The accuracy of the developed method was determined using certified reference material (SRM 3101a), with a standard addition procedure. The method was used for the pre‐concentration of Al in blood samples of patients with neurological disorders. 相似文献
102.
Ion population fraction calculations using improved screened hydrogenic model with l-splitting
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Amjad Ali G Shabbir Naz Rukhsana Kouser Ghazala Tasneem M Saleem Shahzad Aman-ur-Rehman M H Nasim 《中国物理 B》2018,(10)
Ion population fraction(IPF) calculations are very important to understand the radiative spectrum emitted from the hot dense matter. IPF calculations require detailed knowledge of all the ions and correlation interactions between the electrons of an ion which are present in a plasma environment. The average atom models, e.g., screened hydrogenic model with l-splitting(SHML), now have the capabilities for such calculations and are becoming more popular for in line plasma calculations. In our previous work [Ali A, Shabbir Naz G, Shahzad M S, Kouser R, Rehman A and Nasim M H 2018 High Energy Density Phys. 26 48], we have improved the continuum lowering model and included the exchange and correlation effects in SHML. This study presents the calculation of IPF using classical theory of fluctuation for our improved screened hydrogenic model with l-splitting(I-SHML) under local thermodynamic equilibrium conditions for iron and aluminum plasma over a wide range of densities and temperatures. We have compared our results with other models and have found a very good agreement among them. 相似文献
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105.
Manirul Islam Paramita Mondal Anupam Singha Roy Kazi Tuhina 《Transition Metal Chemistry》2010,35(4):491-499
A poly(3,6-dibenzaldimino N-vinyl carbazole) Pd(II) complex has been synthesized and characterized by physicochemical and
spectroscopic techniques. The complex was found to be highly active toward hydrogenation reactions of various organic substrates
under atmospheric pressure at ambient temperature. A tentative reaction mechanism is proposed on the basis of kinetic studies
and isolation of reactive intermediates. The catalyst shows good conversion rates, thermal stability and recyclability. 相似文献
106.
Tabassum Shaheera Zahoor Ameer Fawad Ahmad Sajjad Noreen Razia Khan Samreen Gul Ahmad Hamad 《Molecular diversity》2022,26(1):647-689
Molecular Diversity - Cross-coupling reactions are powerful synthetic tools for the formation of remarkable building blocks of many naturally occurring molecules, polymers and biologically active... 相似文献
107.
108.
Sakhabutdinova Gul’nur N. Raskil’dina Gul’nara Z. Baikova Irina P. Zlotskii Simon S. Sultanova Rimma M. 《Chemistry of Heterocyclic Compounds》2019,55(12):1222-1227
Chemistry of Heterocyclic Compounds - The reaction of substituted 1,3-oxathiolanes with diazocarbonyl compounds in the presence of Cu(OTf)2 and Rh2(OAc)4 was studied. The reaction is accompanied by... 相似文献
109.
110.
R. Trencsényi Z. Gulácsi 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,75(4):511-525
Describing by a Hubbard type of model a thin armchair graphene ribbon in the armchair hexagon chain limit, one shows in exact
terms, that even if the system does not have flat bands at all, at low concentration a mesoscopic sample can have ferromagnetic
ground state, being metallic in the same time. The mechanism is connected to a common effect of correlations and confinement. 相似文献