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31.
32.
S. Seshadri S. Gunasekaran S. Muthu S. Kumaresan R. Arunbalaji 《Journal of Raman spectroscopy : JRS》2007,38(11):1523-1531
The FT Raman and FTIR spectra of flucytosine were recorded in the region 3500–100 cm−1 and 4000–400 cm−1, respectively. The optimized geometry, wavenumber and intensity of the vibrational bands of flucytosine were obtained by ab initio and density functional theory (DFT) levels with complete relaxation in the potential energy surface using the 6‐31G(d,p) and 6‐311G(d,p) basis sets. A complete vibrational assignment aided by the theoretical harmonic frequency analysis is proposed. The harmonic vibrational wavenumbers calculated are compared with experimental FTIR and FT Raman spectra. The observed and the calculated wavenumbers are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar‐type spectrograms. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
33.
Attia Mohammed El Hadi Karthick A. Manokar A. Muthu Driss Zied Kabeel Abd Elnaby Sathyamurthy Ravishankar Sharifpur Mohsen 《Journal of Thermal Analysis and Calorimetry》2021,145(3):1215-1225
Journal of Thermal Analysis and Calorimetry - The Algeria Sahara suffers from the scarcity of drinking water. Solar distillation is one of the simplest and generally inexpensive techniques to solve... 相似文献
34.
A. Antony Muthu Prabhu Madi Fatiha Nouar Leila T. Anantha Raj Inmaculada Navarro-González Maria Jesús Periago Maria Josefa Yáñez-Gascón Horacio Pérez-Sánchez 《Journal of solution chemistry》2018,47(3):409-429
The interactions of the neurotransmitter dopamine (DA) with β-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) was characterized using UV–visible, 2D fluorescence, 3D fluorescence, FT–IR, PXRD and SEM techniques. PM3, PM7 and DFT methods were used to optimize the structures of the inclusion complexes in the gas phase. The absorbance and fluorescence intensities of DA increased in the presence of CDs in aqueous solution. The binding energy, HOMO–LUMO energy gap and Mulliken atomic charges were computed for the inclusion complexes. NBO analysis revealed a greater number of intermolecular hydrogen bonds in DA:HP-β-CD. Experimental and theoretical results suggested that the DA molecule is deeply embedded in the cavities of both CDs. 相似文献
35.
Marimuthu Senthilkumaran Ramesh Kumar Chitumalla Ganesan Vigneshkumar Eswaran Rajkumar Paulpandian Muthu Mareeswaran Joonkyung Jang 《Journal of inclusion phenomena and macrocyclic chemistry》2018,91(3-4):161-169
The interaction of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene is studied using absorption, emission, NMR and electrochemical techniques. The increase in the absorption is observed with the increase in the concentration of p-sulfonatocalix[4]arene. The emission intensity of 2,4,6-triphenylpyrylium cation is also enhanced in the presence of p-sulfonatocalix[4]arene. The electrochemical titration reveals the presence of host–guest interaction. The NMR analysis explains the upper rim interaction of 2,4,6-triphenypyrylium cation with p-sulfonatocalix[4]arene. The mode of binding is studied using computational methods. The quantum chemical simulations reveal the binding orientation of cationic TPP with p-SC4. The calculated complexation energy (??33.19 kcal mol?1) indicates the strong binding nature of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene. 相似文献
36.
Israel V. Muthu Vijayan Enoch Meenakshisundaram Swaminathan 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):149-154
The absorption and fluorescence spectral characteristics of 2-aminodiphenylsulphone (2ADPS) have been investigated in the presence of β-cyclodextrin (β-CDx) in water. Dual emission is observed upon the complexation of 2ADPS in β-CDx. The stoichiometry of the host:guest inclusion complex is found to be 2:1. Steady state and time-resolved fluorescence spectral analysis support the formation of 2:1 complex between β-CDx and 2ADPS. The large enhancement in fluorescence intensity of twisted intramolecular charge transfer (TICT) band in aqueous β-CDx solution is due to the decrease in non-radiative processes. The ground and the excited state pKa values for the monocation-neutral equilibrium of 2ADPS in β-CDx are found to be different from the pKa values in aqueous solution. In the presence of β-CDx, 2ADPS is found to be less basic in the ground and the excited states. 相似文献
37.
Two sulphonated PEES copolymers were synthesized by reacting 75 or 60 mol% silylated hydroquinone sulphonic acid and 25 or 40 mol% of hydroquinone with 4,4′-difluorodiphenyl sulphone. The number average molecular weights determined by GPC were 13.250 and 12.050 g/mol. In the FTIR spectra, in addition to the characteristic absorption bands due to aromatic skeleton, absorption bands associated with sulphonic acid groups were observed at ∼3500, 1172, 1080, 1026, and 706 cm−1. In 1H NMR, the aromatic proton resonance signals were observed between δ = 6.99 and 7.96 ppm. 13C{1H} NMR spectra of these copolymers were complex and in order to resolve this, two-dimensional (2D) NMR techniques were utilized. Heteronuclear single quantum coherence (HSQC), total correlated spectroscopy (TOCSY), and heteronuclear multiple bond correlation (HMBC) were used for assigning the structure of the copolymers. 相似文献
38.
Mariappan Periasamy Muthu Seenivasaperumal Vutukuri Dharma Rao 《Tetrahedron: Asymmetry》2004,15(24):3847-3852
Methods of synthesis of new chiral amino ether derivatives through the opening of aziridinium ions, prepared in situ using trans-(±)-2-(1-N,N-dialkylamino)cyclohexyl mesylate with (R)-(+)-1,1′-bi-2-naphthol, are described. The (R,R,R)-diastereomer was obtained as the major product and isolated as an enantiopure salt, and characterized by single crystal X-ray analysis. The C2-chiral (R,R,R,R,R)-diamino ether was obtained as the major product by opening of the aziridinium ion, prepared using trans-(±)-2-(1-pyrrolidino)cyclohexyl mesylate and (R)-(+)-1,1′-bi-2-naphthol in the presence of aq NaOH. This was also characterized by single crystal X-ray analysis. 相似文献
39.
Enkhtaivan Gansukh Vimala Anthonydhason Somang Jung Doo Hwan Kim Manikandan Muthu Judy Gopal Sechul Chun 《Journal of Cluster Science》2018,29(6):933-941
Nanotechnology has impacted every aspect of human life and the environment. The raising concern against influenza outbreaks is an ongoing issue. With the current drugs and natural remedies, some amount of resolution has been reached. Yet, nothing conclusive has been achieved. With every resource tapped, it is now time to combine strategies. This review highlights the low enthusiasm in this area, where not much has been probed into employing nanomaterials into influenza research. The achievements made through the intervention of nanotechnology into anti influenza research, has been surveyed in this review. Except for a few, not much progress was evidenced. Although significant progress has been achieved with nano inputs, yet nothing much has been done in this direction. This review emphasizes the need to combine strategies and find new remedies against influenza virus using nano platforms. New directions and future perspectives for accessing the nano inputs for combating the influenza issues have been discussed. 相似文献
40.
A simple and ecofriendly protocol has been developed for the expedient synthesis of novel dihydroindeno[1,2-b]pyrrol-4(3aH)-ones from the reaction of ninhydrin and (E)-N-methyl-1-(methylthio)-2-nitroethenamine or (E)-N-(1-(methylthio)-2-nitrovinyl)anilines. 相似文献