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41.
A non-perturbative approach to the time-averaging of nonlinear, autonomous ordinary differential equations is developed based on invariant manifold methodology. The method is implemented computationally and applied to model problems arising in the mechanics of solids. 相似文献
42.
Isobutyric acid in the presence of cyanuric chloride and N‐methylmorpholine was converted into active ester 3 at 0–5 °C, and it was subsequently treated with 3‐aminobenzotrifluoride 4 at 25 °C to furnish corresponding amide 5. This amide finally, on nitration, produced the desired product flutamide, 2‐methyl‐N‐[4‐nitro‐3‐(trifluoromethyl)phenyl]propionamide 6 in good yield. By‐product 2,4,6‐trihydroxy‐1,3,5‐triazine 7 was converted into the useful starting material cyanuric chloride 1 by refluxing with N,N‐diethylamine and POCl3. 相似文献
43.
U. K. Thakur Poonam Verma D. J. Shah R. M. Sawant B. S. Tomar 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):121-124
A method based on ion-chromatography has been developed for determination of Cs and Sr in high level waste (HLW) without matrix separation. The acidity of HLW (3 M HNO3) was decreased to 0.01 M by addition of NaOH. Chromatographic separation of Cs+ and Sr++ in presence of bulk Na+ has achieved using methane sulphonic acid as mobile phase in isocratic and gradient mode. The calibration plot was linear for the concentration range of 0.5–12 mg/L for Cs and 0.025–6 mg/L for Sr with regression coefficients close to 1. RSD obtained for Cs and Sr was 1 and 5 % respectively. Detection limit calculated as 3(S/N) was found to be 20 μg/L for Cs and 30 μg/L for Sr. The standard addition procedure was used to validate the developed method. The samples received from PREFRE, Tarapur and WIP, BARC were analyzed by the new method and the results are presented. 相似文献
44.
Rajiv T. Sawant 《合成通讯》2013,43(15):2269-2277
An efficient organocatalytic route for the preparation of enantioselective synthesis of (S)-1-arylpropan-2-ols derivatives, including the key intermediate of antiepileptic agent (?)-talampanel is described. The key steps involved are L-proline-catalyzed asymmetric α-aminooxylation of aldehydes and regioselective tosylation of diols followed by reduction. 相似文献
45.
An efficient method for the synthesis of new polycyclic skeletons: triaza-benzofluorenes and triaza-pentalenonaphthalene from bicyclic privileged structures imidazopyridine and imidazothiazole, respectively, has been described using the Pictet-Spengler cyclization. 相似文献
46.
Synthesis of Novel Dibenzo‐18‐crown‐6‐ ether‐Functionalized Benzimidazoles and its Applications in Colorimetric Recognition to Hg2+ and as Antifungal Agents
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S. D. Jagadale A. D. Sawant P. P. Patil D. R. Patil A. G. Mulik D. R. Chandam S. A. Sankpal M. B. Deshmukh 《Journal of heterocyclic chemistry》2015,52(2):468-472
New crown ether‐functionalized benzimidazoles was designed and synthesized via formylation of dibenzo‐18‐crown‐6 followed by condensation with different o‐phenylene diamines. The complexation properties of crown ether‐functionalized benzimidazoles with various metals (K+, Ca2+, Ba2+, Co2+, Hg2+) were examined using UV–vis spectroscopy. Hg2+ showed a well‐defined peculiar absorption maximum at 366 nm exclusively. All these newly synthesized compounds were screened for antifungal activity against Aspergillus niger and Aspergillus oryzae, respectively. 相似文献
47.
We report the synthesis of an organic–inorganic hybrid material composed of a conducting polyaniline (PANI) matrix and Prussian blue (PB) network, the latter formed in situ in the polymer matrix. The hybrid was prepared by treating FeCl4 ?-doped PANI with K3Fe(CN)6 unlike the previously reported method of potential cycling to obtain alternate layers of PANI and PB. Cyclic voltammetry and X-ray photoelectron spectroscopy investigations confirmed the formation of a network typical of PB inside the PANI matrix. Infrared spectroscopy points to the formation of an extended network between Fe in PANI matrix and Fe from K3Fe(CN)6. Magnetization studies of the hybrid material showed ferromagnetic ordering with a T c of about 6?K. 相似文献
48.
Mehdi Hasan Arun B. Sawant Rajashri B. Sawant Pratibha G. Loke 《The Journal of chemical thermodynamics》2011,43(9):1389-1394
Densities, viscosities, speed of sound, and IR spectroscopy of binary mixtures of tert-butyl acetate (TBA) with benzene, methylbenzene, and ethylbenzene have been measured over the entire range of composition, at (298.15 and 308.15) K and at atmospheric pressure. From the experimental values of density, viscosity, speed of sound, and IR spectroscopy; excess molar volumes VE, deviations in viscosity Δη, deviations in isentropic compressibility Δκs and stretching frequency ν have been calculated. The excess molar volumes and deviations in isentropic compressibility are positive for the binaries studied over the whole composition, while deviations in viscosities are negative for the binary mixtures. The excess molar volumes, deviations in viscosity, and deviations in isentropic compressibility have been fitted to the Redlich–Kister polynomial equation. The Jouyban–Acree model is used to correlate the experimental values of density, viscosity, and speed of sound. 相似文献
49.
Mehdi Hasan Apoorva P. Hiray Ujjan B. Kadam Dinesh F. Shirude Keshav J. Kurhe Arun B. Sawant 《Journal of solution chemistry》2011,40(3):415-429
Densities, viscosities and speeds of sound of binary mixtures of ethanol, propan-1-ol, butan-1-ol and pentane-1-ol with n-butyl acetate have been measured over the entire range of composition at temperatures of 298.15, 303.15, 308.15 and 313.15 K and atmospheric pressure. From the experimental densities, viscosities and speeds of sound, the excess molar volumes V E, deviations in viscosity ????, and deviations in isentropic compressibility ???? S have been calculated. The excess molar volumes and deviations in isentropic compressibility are positive for all the binary systems studied over the whole composition, while deviations in viscosities are negative for all of the binary mixtures. The excess molar volumes, deviations in viscosity, and deviations in isentropic compressibility have been fitted to a Redlich?CKister type polynomial equation. FTIR and 1H-NMR studies of these mixtures are also reported. 相似文献
50.
Yamgar BA Sawant VA Bharate BG Chavan SS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(1):102-106
A series of complexes of the type [M(L)(dppe)X2]; where M=Zn(II) or Cd(II); L=4-(2'-thiazolylazo)chlorobenzene (L1), 4-(2'-thiazolylazo)bromobenzene (L2) and 4-(2'-thiazolylazo) iodobenzene (L3); dppe=1,2-bis(diphenylphosphino)ethane; X=N3- or NCS- have been prepared and characterized on the basis of their microanalysis, molar conductance, thermal, IR, UV-vis and 1H NMR spectral studies. IR spectra show that the ligand L is coordinated to the metal atom in bidentate manner via azo nitrogen and thiazole nitrogen. An octahedral structure is proposed for all the complexes. The thermal behavior of the complexes revealed that the thiocyanato complexes are thermally more stable than the azido complexes. All the complexes exhibit blue-green emission with high quantum yield as the result of the fluorescence from the intraligand emission excited state. 相似文献