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21.
JPC – Journal of Planar Chromatography – Modern TLC - Sensitive and selective detection of monocrotophos after TLC is possible by use of vanillin as reagent. The product from alkaline... 相似文献
22.
R. Nageswara Rao R. Mastan Vali Dhananjay D. Shinde 《Biomedical chromatography : BMC》2009,23(11):1145-1150
A highly sensitive and selective on‐line two‐dimensional reversed‐phase liquid chromatography/electrospray ionization–tandem mass spectrometry (2D‐LC‐ESI/MS/MS) method was developed and validated to determine rifaximin in rat serum by direct injection. The 2D‐LC‐ESI/MS/MS system consisted of a restricted access media column for trapping proteins as the first dimension and a Waters C18 column as second dimension using 0.1% aqueous acetic acid:acetonitrile as mobile phase in a gradient elution mode. Rifampacin was used as an internal standard. The linear dynamic range was 0.5–10 ng/mL (r2 > 0.998). Acceptable precision and accuracy were obtained over the calibration range. The assay was successfully used in analysis of rat serum to support pharmacokinetic studies. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
23.
Jaiprakash N. Sangshetti Nagnnath D. Kokare Sandeep A. Kotharkar Devanand B. Shinde 《Monatshefte für Chemie / Chemical Monthly》2008,139(2):125-127
Summary. 2,4,5-Triaryl-1H-imidazoles were efficiently synthesized from benzoin or benzil, ammonium acetate, and aromatic or heteroaromatic aldehydes
in the presence of sodium bisulfite as catalyst. The present protocol offers significant improvements for the synthesis of
2,4,5-triaryl-1H-imidazoles with regard to yield of products, simplicity in operation, and cheap catalyst. 相似文献
24.
We have developed simple, greener, safer multicomponent synthesis series of 4-arylidene-2-phenyl-5(4H) oxazolones 4(a-r) catalyzed by Bronsted acid ionic liquid as triethylammonium hydrogen sulfate [Et3NH][HSO4] and catalytic amount of acetic anhydride and sodium acetate with excellent yields (90–99%). The protocol offers economical, environmentally benign, solvent-free conditions, and recycle–reuse of the catalyst and easily available starting as benzoyl chloride 1, amino acid 2 and a variety of aldehydes 3. The cyclization followed by condensation of benzoyl chloride, amino acid, and a variety of aldehydes catalyzed by ILs [Et3NH][HSO4] and catalytic amount of acetic anhydride and sodium acetate. The final products were confirmed by their characterization data such as FTIR, 1H-NMR, 13C-NMR, Mass, high-resolution mass spectra and were compared with its reported method. 相似文献
25.
Pravin V. Shinde 《Tetrahedron letters》2010,51(9):1309-6782
A one-pot three-component condensation of an aldehyde, malononitrile, and thiophenol has been achieved by conventional and ultrasound method. The reaction has been catalyzed by boric acid in aqueous medium. This protocol afforded corresponding 2-amino-3,5-dicarbonitrile-6-thio-pyridines in shorter reaction times and high yields with the green aspects by avoiding toxic catalysts and solvents. 相似文献
26.
The nanocrystalline samples of La0.9Sr0.1MnO3 (LSMO) have been prepared by the combustion method. The thermo gravimetric analysis of precursor was carried out. The X-ray diffraction study confirms the rhombohedral crystal structure without any other impurity phases. The morphology and magnetic properties change with annealing temperature. The saturation magnetization increases linearly and coercivity of the nanoparticles varies significantly as annealing temperature increases. The maximum saturation magnetization and lower coercivity found for the sample heat treated at 1200 °C are 52.5 emu/g and 10.7 Oe respectively. 相似文献
27.
P. W. Khirade Ajay Chaudhari J. B. Shinde S. N. Helambe S. C. Mehrotra 《Journal of solution chemistry》1999,28(8):1031-1043
Complex reflection coefficients for 2-ethoxyethanol–dimethylformamide (DMF), ethanol–DMF, and 1-propanol–DMF mixtures at several temperatures from 20 to 50° and the frequency range 10 MHz to 10 GHz were determined by time-domain spectroscopy in reflection mode. Fourier transforms and least-squares fitting were used to obtain complex permittivity, static dielectric constant, and relaxation time. The excess dielectric parameters, Kirkwood correlation factors, and thermodynamic properties for the binary mixtures were also determined. The static dielectric constant for the mixtures was fitted well with the modified Bruggeman model. 相似文献
28.
The Dy3+ and Eu3+ activated K3Al2 (PO4)3 phosphors were prepared by a combustion synthesis. From a powder X-ray diffraction (XRD) analysis the formation of K3Al2 (PO4)3 was confirmed. In the photoluminescence emission spectra, the K3Al2(PO4)3:Dy3+ phosphor emits two distinctive colors: blue and yellow whereas K3Al2(PO4)3:Eu3+ emits red color. Thus the combination of colors gives BYR (blue–yellow–red) emissions can produce white light. These phosphors
exhibit a strong absorption between 340 and 400 nm which suggest that present phosphor is a promising candidate for producing
white light-emitting diodes (LED). 相似文献
29.
P. M. Kadam N. L. Tarwal P. S. Shinde R. S. Patil H. P. Deshmukh P. S. Patil 《Applied Physics A: Materials Science & Processing》2009,97(2):323-330
Suitable host lattice and morphology for easy intercalation and deintercalation process are crucial requirements for electrochromic
device. In this investigation, the evolution of structural and morphological changes and their effect on electrochromic (EC)
properties of spray-deposited WO3 thin films are studied. Films of different morphologies were deposited from an ammonium tungstate precursor solution using
a novel pulsed spray pyrolysis technique (PSPT) on tin-doped indium oxide (ITO) coated glass substrates by varying quantity
of spraying solution. Interesting morphological transition from beads-to-wires-to-fibers as a function of quantity of sprayed
solution has been demonstrated. The porosity, crystallinity and “open” structures in the films consisting of beads, wires,
and fiber-like morphology enabled us to correlate these aspects to their EC performance. WO3 films comprising wire-like morphology (20 cc spraying quantity) exhibited better EC properties both in terms of coloration
efficiency (42.7 cm2/C) and electrochemical stability (103 colored/bleached cycles) owing to their adequate open structure, porosity, and amorphicity, compared with the films having
bead/fiber-like morphology. 相似文献
30.
Lokhande A. C. Shinde N. M. Shelke A. Babar P. T. Kim Jin Hyeok 《Journal of Solid State Electrochemistry》2017,21(9):2747-2751
Journal of Solid State Electrochemistry - Green synthesis of optically active silver nanoparticles (Ag) containing thin film on flexible plastic strip substrate has been carried using guava leaf... 相似文献