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Summary A simple method based on circular thin-layer chromatography is described for the separation of aromatic and,-unsaturated aldehydes as their isonicotinoyl hydrazones. The development of the chromatoplate is complete within 2 minutes.
Zusammenfassung Aromatische und,-ungesättigte Aldehyde lassen sich durch ringförmige Dünnschichtchromatographie ihrer Isonikotinoylhydrazone trennen. Die Entwicklung der Dünnschichtplatten ist innerhalb 2 Minuten zu bewerkstelligen.
Résumé On décrit une méthode simple fondée sur la chromatographie circulaire en couche mince pour séparer les aldéhydes aromatiques et, non saturés, sous forme de leurs hydrazones isonicotinoyles. Le développement de la chromatoplaque est complet en deux minutes.相似文献
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S. Shahzadi K. Shahid S. Ali M. Mazhar K. M. Khan 《Journal of the Iranian Chemical Society》2005,2(4):277-288
A brief account is given of the synthesis, structural chemistry and the antibacterial, antifungal and cytotoxic effects of organotin complexes of 2-[(2,4-dichloroanilinocarbonyl)]benzoic acid. The unimolar and bimolar substitution products have been characterized by elemental analysis and spectral studies, including IR, 1H NMR, 13C NMR, 119Sn NMR, and mass spectra. The data support the binding of the oxygen atom to the tin atom in [R2Sn(OOCR’)2] and [R3Sn(OOCR’)] (R = Me, Bu, and Ph, R’ = 2-[(2,4-dichloroanilinocarbonyl)]benzoic acid). Based on these studies, with a coordination number of four, a distorted tetrahedral geometry has been proposed for the resulting derivatives in solution. The free ligand (R’/COOH) and its respective tin complexes were tested in vitro against a number of microorganisms to assess their biocidal properties and to correlate them with the structures of the derivatives. 相似文献
15.
Shahid Muhammad Kim Kwangsoo Kim Guinyun Naik Haladhara Zaman Muhammad Lee Young-Ouk Cho Young-Sik 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1971-1981
Journal of Radioanalytical and Nuclear Chemistry - We measured excitation functions for the production of the 108m,108g,109g,110m,110g,111gIn, the 109g,111mCd, and the 105g,106m,110m,111gAg in... 相似文献
16.
The double Suzuki cross‐coupling reaction has successfully been applied for the synthesis of 5,5′‐(5‐butoxy‐1,3‐phenylene)bis(2‐chloropyrimidine) with two reactive chloro groups and an alkoxy side chain starting from 2‐chloropyrimidin‐5‐ylboronic acid and 1,3‐dibromo‐5‐butoxybenzene. The reactivity of this dielectrophile was tested by reaction with aniline and phenol, a nitrogen and oxygen nucleophile, respectively. The new dielectrophile would further provide an ideal platform for the construction of large hetero‐atom bridged macrocycles for desired properties and functions in supramolecular and material chemistry. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
Asma Hayat Shazia Bashir Muahmamd Shahid Rafique Mahreen Akram Khaliq Mahmood Saman Iqbal Asadullah Dawood Arooj 《Optics and Spectroscopy》2016,120(1):1-8
The optical characteristics of biological tissues sampled from the anterior abdominal wall of laboratory rats are for the first time experimentally studied in a wide wavelength range (350-2500 nm). The experiments have been performed in vitro using a LAMBDA 950 (PerkinElmer, United States) spectrophotometer. Inverse Monte Carlo simulation is used to restore the spectral dependences for scattering and absorption coefficients, as well as the scattering anisotropy factor for biological tissue based on the recorded spectra of diffuse reflection and total and collimated transmissions. 相似文献
18.
Rafiq Shahid Abbas Zaheer Nawaz Muhammad Alharbi Sayer Obaid 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3269-3279
Journal of Thermal Analysis and Calorimetry - A numerical model is developed to study the effects of temperature-dependent viscosity on heat transfer in magnetohydrodynamic flow of micropolar fluid... 相似文献
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Shahid Iqbal Paula Rivière Farhan Saif 《International Journal of Theoretical Physics》2010,49(10):2540-2557
Gazeau-Klauder coherent states are developed for power-law potentials and their evolution in space and time is analyzed. We
show that these states follow classical dynamics as long as the underlying energy spectrum is linear, otherwise they follow
a classical-like evolution upto a few classical periods and disperse thereafter, despite its special construction. Auto-correlation
function and probability density as a function of space and time explain the spatio-temporal behavior of these states. 相似文献