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51.
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In this study, affinity capillary electrophoresis (ACE) and quantum mechanical density functional theory (DFT) calculations were combined to investigate non-covalent binding interactions between the hexaarylbenzene-based receptor (R) and alkali metal ions, Rb(+) and Cs(+) , in methanol. The apparent binding (stability) constants (K(b) ) of the complexes of receptor R with alkali metal ions in the methanolic medium were determined by ACE from the dependence of effective electrophoretic mobility of the receptor R on the concentration of Rb(+) and Cs(+) ions in the BGE using a non-linear regression analysis. The receptor R formed relatively strong complexes both with rubidium (log K(b) =4.04±0.21) and cesium ions (log K(b) =3.72±0.22). The structural characteristics of the above alkali metal ion complexes with the receptor R were described by ab initio density functional theory calculations. These calculations have shown that the studied cations bind to the receptor R because they synergistically interact with the polar ethereal fence and with the central benzene ring via cation-π interaction. 相似文献
53.
S. Bindya Wing‐Tak Wong M. A. Ashok H. S. Yathirajan R. S. Rathore 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):o546-o548
In the structure of the title salt [systematic name: 3‐(10,11‐dihydro‐5H‐dibenzo[a,d][7]annulen‐5‐ylidene)‐N,N‐dimethylpropan‐1‐aminium 2,4,6‐trinitrophenolate] of a tricyclic antidepressant, C20H24N+·C6H2N3O7−, the dimethylaminopropyl subunit possesses a classical static conformational disorder. The central cycloheptadiene ring adopts a bent conformation that is intermediate between boat and chair forms, leading to a butterfly shape for the hetero‐tricyclic moiety. In a complementary fashion, donors from amitriptyline and acceptors from picrate form intermolecular C—H...O hydrogen bonds and N—H...O salt bridges. These hydrogen bonds cluster amitriptyline and picrate ions into a closed R44(36) hetero‐tetramer, whereas intermolecular C—H...π interactions between amitriptyline ions cluster them into homo‐dimers. Significant π–π stacking interactions are also observed between aromatic rings of amitriptyline and picrate, and these, combined with the C—H...π interactions, associate molecules into linear arrays along the [11] direction. 相似文献
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H. S. Rathore K. Ishratullah C. Varshney G. Varshney S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2008,94(1):75-81
Copper diethyldithiocarbamate, cadmium diethyldithiocarbamate, lead diethyldithiocarbamate, nickel diethyldithiocarbamate
and zinc diethyldithiocarbamate have been synthesized. They have been characterized using TG, DTA, IR spectroscopy, X-ray
and atomic absorption spectrophotometry. The thermal conversion of the compounds is 54.36–88% at 1000°C. Their solubility
in sodium hydroxide, mineral acids, organic solvents, distilled water and salts solution has been measured. Fungicidal activity
of the dithiocarbamates has been tested by well or cup diffusion method using five fungi species. Their activity has also
been tested by broth dilution method using six bacterial species. Minimum Inhibitory Concentration (bactericidal) is 6.25–25.00
μg mL−1. 相似文献
56.
α,β-Unsaturated anilides bearing allylic leaving groups undergo photochemical electrocyclic ring closure to produce zwitterionic intermediates which eliminate carboxylate and phenolate leaving groups. 相似文献
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A. Kumar J. V. Sonawane N. S. Rathore H. N. Kapur A. K. Venugopalan D. D. Bajpai 《Journal of Radioanalytical and Nuclear Chemistry》2002,254(3):469-478
Partitioning of minor alpha-emitting actinides, especially U, Pu and Am from medium active alkaline waste is possible from intermediate level liquid wastes (ILLW) produced during spent fuel reprocessing following Purex process. This paper deals with the efficient removal of alpha-activity from ILLW by solvent extraction process. Counter current batch extraction with O/A ratio 2:1 as well as multistage mixer settler has demonstrated that most of the alpha-activity was removed from the alkaline effluents using 20% Versatic-10 (V-10) in dodecane after giving 3 to 4 contacts, thus converting alkaline waste as non-alpha waste. Under the optimum conditions (pH 9.0-9.5 and VA-10), both Pu(IV) and Am(III) are highly extractable whereas U(VI) is relatively poorly extracted. To assess the applicability of this process for regular treatment of the waste, a feasibility study on pilot plant scale using six stage mixer settler was operated to treat the ILLW. The results indicated that almost >99.90% alpha-emitting actinides are removed. Dilute nitric acid (0.5M HNO3) served as the most efficient strippant for all these actinides. This facilitate an easy regeneration of the extractant which can be recycled. This method is useful in obtaining alpha-free wastes and had positive impact on ease and safety aspects during subsequent waste treatment and long term storage. 相似文献