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11.
Sorption of tracer Am3+ to silicate particles was studied as a function of pcH (4 to 9) and of ionic strength [0.20M to 1.50M (NaClO4)] at 298 K. The sorption increased with increased pcH from 4 to 6 above which saturation was observed. The insensitivity
of Am3+ sorption to increased ionic strength indicates inner-sphere complexation with the surface silicate sites. The effects of
different complexing anions such as carbonate, acetate, oxalate, phosphate, citrate, EDTA and humic acid, on Am3+ sorption were investigated. Synergistic enhancement in Am3+ sorption was observed in the presence of phosphate (4≤pcH≤7) and acetate (4≤pcH≤5) ligands at 0.20M NaClO4. The presence of the other ligands inhibited Am3+ sorption in the order: EDTA > citrate > oxalate > carbonate. Am3+ sorption in the presence of HA (25.00 mg/l) increased in the pcH range of 4.0 to 5.5, then decreased. Increased ionic strength
enhanced Am3+ sorption in the presence of 25.00 mg/l HA for 4≤pcH≤9. The sorption increased in the presence of a mixture of HA (25.00 mg/l)
and phosphate (1.00·10−3M) as compared to that of HA (25.00 mg/l) alone. The presence of Fe3+ (1.00·10−4M) enhanced Am3+ sorption at pcH∼4 but suppressed it from pcH of 5 to 9; 1.00·10−4M of Ca2+ and of UO22+ ions had no effect on the sorption profile.
On leave from Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai -400 085, India. 相似文献
12.
Dighe Vidya V. Pathak Gayatri M. Tulpule Ketan M. Gokarn Vijay N. 《平面色谱法杂志一现代薄层色谱法》2007,20(3):179-182
JPC – Journal of Planar Chromatography – Modern TLC - A sensitive high-performance thin-layer chromatographic method has been established for quantification of apigenin in dried root... 相似文献
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Quinazoline is a heterocyclic compound having biological activities. It is aromatic in nature having bicyclic structure containing benzene ring and pyrimidine ring. Quinazoline and its derivatives are found to have wide range of biological activities that is anticancer, analgesic, antimicrobial, antihypertensive, anticonvulsant, antimalarial, antitumor, and anti-tubercular activities. The purpose of this review is to highlight the recent researches made by researchers on various biological activities of quinazoline derivatives on different targets. 相似文献
15.
V. C. Adya M. Mohapatra Nimai Pathak Mithlesh Kumar N. S. Hon S. K. Thulasidas M. J. Kulkarni V. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(1):341-346
This work presents the investigation of some commercially available and commonly used Si3N4 foils prepared with LPCVD technique. The density and the stoichiometry of these films were determined by Rutherford backscattering spectroscopy and profilometry, while the study of impurities was achieved with particle induced X-ray emission method. It was found that the density of the studied Si3N4 films is significantly less (~2.71 g cm?3), while the stoichiometry is close to the values of the bulk material. The results were verified by measuring the ion energy loss through the films by scanning transmission ion microscopy. 相似文献
16.
The present article describes a working or combined calibration curve in laser-induced breakdown spectroscopic analysis, which is the cumulative result of the calibration curves obtained from neutral and singly ionized atomic emission spectral lines. This working calibration curve reduces the effect of change in matrix between different zone soils and certified soil samples because it includes both the species' (neutral and singly ionized) concentration of the element of interest. The limit of detection using a working calibration curve is found better as compared to its constituent calibration curves (i.e., individual calibration curves). The quantitative results obtained using the working calibration curve is in better agreement with the result of inductively coupled plasma–atomic emission spectroscopy as compared to the result obtained using its constituent calibration curves. 相似文献
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Treatment of 1H-4,5-dihydro-3-aryl-5-(2-hydroxyaryl)pyrazole with o-dibromoxylene under liquid-liquid phase transfer catalytic conditions using tetra-n-butylammonium hydrogen sulphate or [18]-crown-6 as PT catalyst, benzene/chloroform as organic phase and 50% aqueous potassium hydroxide as second phase, afforded novel 2,5,9,10-tetrahydro [7,8-g] benzo-8-arylpyrazolo[4,5-e] [1,5-b] benzoxazonines. 相似文献
19.
Total synthesis of (Z) pulchellalactam, a CD protein tyrosine phosphatase inhibitor, from commercially available methallyl chloride employing ring‐closure metathesis (RCM) as a key step is described. 相似文献
20.
Sachin S. Pathak R. D. Bhanushali I. C. Pius S. K. Mukerjee 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):1641-1648
Titania–silica microspheres have been prepared by sol–gel process. Internal gelation route, which use hexamethylenetetramine as the source of ammonia was used for the preparation spherical gel particles. A cationic surfactant, cetrimide was added in the feed broth for introducing meso-porosity in the gel network. Further paraffin oil emulsion was incorporated in the feed broth before gelation for the formation of larger pores in the gel network. The spherical gel particles thus obtained were washed and heat treated under controlled conditions to remove the entrapped surfactant, paraffin oil and other organic compounds resulting in highly porous intact titania–silica microspheres. The material was characterized by surface area, porosity and by SEM photomicrographs. The ion exchange property of this material was studied using the sorption of plutonium on this material from carbonate medium by distribution coefficient studies and ion exchange column loading and elution experiments. 相似文献