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11.
Gold Decorated Graphene by Laser Ablation for Efficient Electrocatalytic Oxidation of Methanol and Ethanol
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V. Lakshman Kumar R. S. Sai Siddhardha Adarsh Kaniyoor Ramakrishna Podila Muralikrishna Molli Sai Muthu Kumar V K. Venkataramaniah S. Ramaprabhu A. M. Rao Sai Sathish Ramamurthy 《Electroanalysis》2014,26(8):1850-1857
A well‐known limitation in the fabrication of metal‐graphene composite has been the use of surfactants that strongly adsorb on the surface and reduce the performance of the catalyst. We demonstrate here a novel one‐pot synthesis of gold nanoparticles by laser ablation of gold strip and in‐situ decoration on graphene substrate. Not only the impregnation of nanoparticles was linker free, but also the synthesis by itself was surfactant‐free. The composite materials were well characterized morphologically and functionally using electron microscopy, X‐ray and electron diffraction, Raman spectroscopy, Zeta potential, electrochemical measurements and UV‐Visible spectroscopic techniques. This linker‐free gold‐graphene based composite has been employed for catalytic applications pertaining to electrooxidation. We have explored the use of this composite as a binder‐free electrode in electrocatalytic oxidation of methanol and ethanol in alkaline medium. Additionally, the onset potential for ethanol oxidation was found to be more negative, ?100 mV, an indication of its promising application in direct ethanol fuel cells. 相似文献
12.
The total synthesis of oxacalothrixins, an isostere of biologically important carbazoloquinone alkaloid, calothrixin B was achieved from 2-acetyl-3-methylbenzofuran. An iodine/TBHP-mediated oxidative cyclization of benzofuranyl-enamine has been employed as a key step to synthesize, the crucial intermediate 1-hydroxy dibenzofurancarbaldehyde. The latter upon reductive cyclization followed by PIDA-mediated oxidation furnished oxacalothrixin B and its analogues. 相似文献
13.
Mathur Nadarajan Kathiravan Ramalingam Karthick Naggapan Muthu Karuppan Muthukumar Manickam Velan 《Applied biochemistry and biotechnology》2010,160(7):2000-2013
This study presents sonoassisted microbial reduction of hexavalent chromium (Cr(VI)) using Bacillus sp. isolated from tannery effluent contaminated site. The experiments were carried out with free cells in the presence and
absence of ultrasound. The optimum pH and temperature for the reduction of Cr(VI) by Bacillus sp. were found to be 7.0 and 37 °C, respectively. The Cr(VI) reduction was significantly influenced by the electron donors
and among the various electron donors studied, glucose offered maximum reduction. The ultrasound-irradiated reduction of Cr(VI)
with Bacillus sp. showed efficient Cr(VI) reduction. The percent reduction was found to increase with an increase in biomass concentration
and decrease with an increase in initial concentration. The changes in the functional groups of Bacillus sp., before and after chromium reduction were observed with FTIR spectra. Microbial growth was described with Monod and Andrews
model and best fit was observed with Andrews model. 相似文献
14.
Spectral characteristics of 1-(2,4-diamino phenylazo) naphthalene (FBRR, fat brown RR) and 4-aminoazobenzene (AAB) have been
studied in various solvents, varying hydrogen ion concentrations and in β-cyclodextrin (β-CD). The inclusion complex of FBRR
and AAB with β-CD were analysed by UV-visible, fluorometry and CAche-DFT methods. Solvent study reveals that only azo tautomer
is present in both compounds and the large red shifted absorption and emission maxima of FBRR indicate naphthalene ring effectively
increases the π-π* transition. Unusual red shift is observed in acid solutions suggests azonium-ammonium tautomer is present
in both molecules. In β-CD solutions, the large hypsochromic shift is observed in S0 and S1 states indicates ortho amino group of FBRR molecule is entrapped in the β-CD cavity and the large bathochromic shift for AAB in the S1 state indicates 1:1 inclusion complex is formed. 相似文献
15.
In this paper we study integration with respect to a bimeasure with finite semivariation. The bimeasures as well as the functions
to be integrated, take on their values in Banach spaces.
Entrata in Redazione il 25 settembre 1998 e, in versione riveduta, il 25 giugno 1999. 相似文献
16.
A. Antony Muthu Prabhu G. Venkatesh N. Rajendiran 《Journal of solution chemistry》2010,39(7):1061-1086
The absorption and fluorescence spectra of sulfamethoxazole (SMO), sulfisoxazole (SFO), sulfathiazole (STO) and sulfanilamide
(SAM) in different solvents, pH and β-cyclodextrin (β-CD) have been analyzed. The inclusion complexes of the above sulfa drugs with β-CD were investigated by UV-visible spectroscopy, fluorometry, DFT, SEM, FT-IR and 1H NMR. The solvent study indicates that the position of the substituent (oxazole or thiazole group) in the SAM molecule (R–SO2–NH-group) is not the key factor to change the absorption and emission behavior of these sulpha drug molecules. In aqueous
solution, a single fluorescence band (340 nm) was observed whereas in solutions of β-CD dual emission (430 nm) was noticed in sulpha drug compounds. Formation of the inclusion complex in SMO, SFO and STO should
result dual emission which is due to a Twisted Intramolecular Charge Transfer band (TICT). The β-CD study indicates that (i) sulpha drugs form 1:1 inclusion complexes with β-CD and (ii) the red shift and the presence of TICT in the β-CD medium confirms heterocyclic ring encapsulated in the β-CD cavity with the aniline ring present on the out side of the β-CD cavity. 相似文献
17.
18.
Theranostics is an emerging area in nanomedicine where therapeutic and diagnostic platforms are integrated together to perform multiple functions such as disease diagnostic and therapy, noninvasive method to determine the targeted delivery of drugs, and evaluation of drug efficacy. This review gives an overview of the different therapeutic and diagnostic strategies used to construct a theranostic system. The importance of polymer‐based theranostic carriers is presented. The different types of polymeric carriers such as micelles, liposomes, dendrimers, and nanogels explored for theranostic applications are also presented. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
19.
J. Premakumari G. Allan Gnana Roy A. Antony Muthu Prabhu G. Venkatesh V. K. Subramanian N. Rajendiran 《Journal of solution chemistry》2011,40(2):327-347
The spectral characteristics of 2,4-dihydroxyazobenzene (DHAB, sudan orange G) and 4-hydroxyazobenzene (HAB) have been studied
in various solvents, different hydrogen ion and β-cyclodextrin (β-CD) concentrations, and are compared with azobenzene (AB). The inclusion complexes of the above molecules with β-CD were analyzed by UV-vis spectrometry, flourometry, FT-IR, 1H NMR, SEM and DFT methods. The solvent study shows that only the azo form is present in DHAB and HAB molecules. The unusually
large red shift observed in acidic solutions indicates both molecules exhibit azo-hydrazo tautomerization. In the β-CD solutions, the increase in fluorescence intensity and large bathochromic shift in the S1 state indicates that DHAB and HAB form 2:2 inclusion complexes, whereas AB forms a 1:1 inclusion complex. 相似文献
20.
This paper presents an interior point method to determine the minimum energy conformation of alanine dipeptide. The CHARMM energy function is minimized over the internal coordinates of the atoms involved. A barrier function algorithm to determine the minimum energy conformation of peptides is proposed. Lennard-Jones 6-12 potential which is used to model the van der Waals interactions in the CHARMM energy equation is used as the barrier function for this algorithm. The results of applying the algorithm for the alanine dipeptide structure as a function of varying number of dihedral angles are reported, and they are compared with that obtained from genetic algorithm approach. In addition, the results for polyalanine structures are also reported. 相似文献