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81.
Karthikeyan B Saravanan B 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(3):619-623
Raman spectra of phenoxyacetic acid and chlorine substituted phenoxyacetic acids viz., o-chlorophenoxyacetic acid, p-chlorophenoxyacetic acid and 2,6-dichlorophenoxyacetic acid have been analysed with the aid of abinitio theoretical calculations. The effect of chlorine substituents on the Raman spectra of phenoxyacetic acid have also been analysed by considering some important vibrational modes. 相似文献
82.
Noor-ul H. Khan S. Saravanan Rukhsana I. Kureshy Sayed H.R. Abdi Arghya Sadhukhan Hari C. Bajaj 《Journal of organometallic chemistry》2010,695(8):1133-6983
Chiral dimeric vanadium (V) salen complex (10 mol%) derived from 5,5-Methylene di-[(S,S)-{N-(3-tert-butyl salicylidine)-N′-(3′,5′-di-tert-butyl salicylidene)]-1,2-cyclohexanediamine] with vanadyl suphate followed by auto oxidation was used as efficient catalyst for enantioselective Strecker reaction of N-benzylimines with TMSCN at −30 °C. Excellent yield (92%) of α-aminonitrile and high chiral induction was achieved (ee up to 94%) in case of 2-methoxy substituted N-benzylimines in 10 h. The catalytic system worked well up to four cycles with retention of enantioselectivity. 相似文献
83.
Mandal S Sathish M Saravanan G Datta KK Ji Q Hill JP Abe H Honma I Ariga K 《Journal of the American Chemical Society》2010,132(41):14415-14417
Although artificial capsule structures have been thoroughly investigated, functionality at the surfaces of their interiors has been surprisingly overlooked. In order to exploit this aspect of capsular structure, we here report the breakthrough fabrication of metallic (platinum) microcapsules with sufficient accessibility and electroactivity at both interior and exterior surfaces (open-mouthed platinum microcapsules), and also we demonstrate improvements in electrochemical and catalytic functions to emphasize the practical importance of our concept. The open-mouthed platinum microcapsules were prepared by template synthesis using polystyrene spheres, where surface-fused crystalline nanoparticles formed a capsule shell. Subsequent removal of the polystyrene spheres induced formation of mouth-like openings. The open-mouthed platinum microcapsules exhibit a substantial increase of their electrode capability for methanol oxidation and catalytic activities for carbon monoxide (CO) oxidation. Notably, activity loss during CO oxidation due to undesirable particle agglomeration can be drastically suppressed using the open-mouthed microcapsules. 相似文献
84.
85.
K. SethuSankar S. Saravanan D. Velmurugan Masood Parvez 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o156-o158
The title compound, 4′‐methoxy‐α,2,3′,4‐tetranitrostilbene, C15H10N4O9, crystallizes in the centrosymmetric space group P21/c with one molecule in the asymmetric unit. The phenyl rings are inclined to one another and form a dihedral angle of 57.4 (1)°. The size of this angle is a result of intermolecular C—H⃛O interactions involving the phenyl H atoms. The torsion angle between the phenyl rings, −7.5 (3)°, indicates a cis geometry between them. The methoxy group is almost coplanar with the phenyl ring, and the nitro groups are twisted with respect to the phenyl rings because of the short H⃛O contacts. The crystal packing is stabilized by C—H⃛O hydrogen bonds, and the intermolecular hydrogen bonds form a C(12) graph‐set chain running along the [010] direction. 相似文献
86.
Crystallography Reports - The title compound, 1-(4-(5,6-dihydropyridazin-1(4H)-yl)phenyl)-N-methylmethanesulfonamide (C12H17N3O2S), was isolated as an impurity during the preparation of sumatriptan... 相似文献
87.
88.
This paper deals with Kolmogorov criterion for best uniform coapproximation and strongly unique best uniform coapproximation. Some relations between best uniform approximation and best uniform coapproximation are obtained. Some equalities and best uniform coapproximation are connected. 相似文献
89.
GaAs epitaxial layers of high structural quality have been realised from Ga–As–Bi melt using liquid-phase epitaxy (LPE). LPE grown GaAs epitaxial layer using bismuth solvent on GaAs substrate has been found to be of good structural perfection as compared to layers using gallium solvent. The temperature-dependent PL spectra of GaAs layer, grown from Ga+Bi mixed solvent has shown that the use of bismuth does not change the band energy. ECV depth profile of heavily zinc-doped epitaxial layer shows uniform doping in the GaAs layer grown using gallium solvent as compared to the layer grown using bismuth solvent. 相似文献
90.
Development and investigation of the flexible hydrogen sensor based on ZnO-decorated Sb2O3 nanobelts
Natarajan Pradeep Gopal Tamil Selvi Uma Venkatraman Quyet Van Le Soon Kwan Jeong Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy Andrews Nirmala Grace 《Materials Today Chemistry》2021
Hydrogen is regarded as the next-gen fuel for vehicles to avoid the emission of toxic gases, which needs a continuous monitoring of the concentration level. In the design of the H2 sensor, especially of flexible type, a sensing layer will be blended, which affects the sensing performance of the device. Based on this concern, the present investigation is carried out to understand the effect of the bending angle toward the sensing performance of bare and ZnO (n-type)-decorated Sb2O3 (p-type) nanobelt–based sensors for hydrogen gas. The sensing element was prepared by the thermal chemical vapor deposition followed by the drop-casting method. Furthermore, the role of the zinc precursor (molar concentration—1 M–3 M) on the preparation of ZnO-decorated Sb2O3 nanobelts was studied. Various techniques were used to confirm the formation of ZnO-decorated nanobelts such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), and Fourier transform infrared spectroscopy (FTIR). From these analyses, 1 M concentration of the zinc precursor shows uniform distribution of nanoparticles over the surface of Sb2O3 nanobelts. However, agglomeration was observed when the concentration of the zinc precursor increases from 1 M to 3 M. Later, the prepared nanobelts were deposited on the OverHead Projector (OHP) sheet by the doctor blade method for sensing hydrogen gas at 100 °C at a concentration of 1000–3000 ppm. In addition to it, the effect of the substrate bending angle (0°, 45°, 60°, and 90°) was analyzed at a fixed concentration of H2 gas (1000 ppm). From this study, it is clear that the highest sensing response was achieved for 1 M decorated nanobelts compared with bare as well as other concentrations because of uniform distribution of nanoparticles on the surface of nanobelts. Moreover, the prepared sample demonstrates better sensing performance with the bending of substrates, which suggests that the prepared sensor could be used for flexible electronic devices. The prepared nanobelts show a good H2 gas–sensing response even with bending of the substrates. The work suggests that the prepared sensor is applicable for flexible electronic devices. 相似文献