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1.
An efficient and direct procedure for the synthesis of amidoalkyl-2-naphthol derivatives has been described. The process employs a three-component cyclocondensation reaction in one-pot using β-naphthol, aromatic aldehyde and acetamide or benzamide in the presence of silica chloride accelerated by ultrasound giving the product in excellent yield in very short duration. 相似文献
2.
Enantioselective synthesis of possible diastereomers of heptadeca-1-ene-4,6-diyne-3,8,9,10-tetrol, a structure proposed for the natural product isolated from Hydrocotyle leucocephala is accomplished. The reported spectral data of the natural product did not match those of any of the isomers that were synthesized and established that the structure proposed for the natural product is not correct and requires revision. 相似文献
3.
A one-pot three-component condensation of an aldehyde, 2-naphthylamine, and acetamide has been achieved by sonication at 35 kHz. The reaction is catalysed by silica chloride in aqueous medium. This protocol afforded corresponding 1-amidoalkyl-2-naphthylamines in shorter reaction durations, and in high yields. The method involves simple work-up procedure, and avoids use of hazardous reagents. 相似文献
4.
JPC – Journal of Planar Chromatography – Modern TLC - An important bioactive molecule, ursolic acid was isolated from the leaves of Diospyros melanoxylon and characterized with help of... 相似文献
5.
BHOLANATH MANDAL KAKALI DATTA ASOK K. MUKHERJEE MANAS BANERJEE 《Molecular physics》2013,111(11):1609-1611
Characteristic polynomial coefficients of three classes of graph, namely Ln + n(p), Cn + n(p) and K 1,n-1 + n(p), which are known to have reciprocal pairs of eigenvalues, have been shown to be generated by simple manipulation of the Pascal's triangle. 相似文献
6.
SHYAMAL MONDAL SATYA PRATAP SINGH SOURABH MUKHOPADHYAY ADITYA DATE KAMAL HUSSAIN SHOUVIK MUKHERJEE PRASANTA KUMAR DATTA 《Pramana》2014,82(2):313-319
A comparative study in terms of optimized output power and stability is made on cascaded second-order nonlinear optical mode-locking with KTP, BBO and LBO crystals for both 1064 nm and 532 nm. Large nonlinear optical phase shift achieved in a non-phase-matched second harmonic generating crystal, is transformed into amplitude modulation through soft aperturing the nonlinear cavity mode variation at the laser gain medium to mode-lock a Nd:YVO4 laser. The laser delivers stable dual wavelength cw mode-locked pulse train with pulse duration 10.3 ps and average power of 1.84 W and 255 mW at 1064 nm and 532 nm respectively for the optimum performance in type-II KTP crystal. The exceptional stability achieved with KTP is accounted by simulating the mode-size variation with phase mismatch. 相似文献
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8.
An approximation method based on the iterative technique is developed within the framework of linear delta expansion (LDE)
technique for the eigenvalues and eigenfunctions of the one-dimensional and three-dimensional realistic physical problems.
This technique allows us to obtain the coefficient in the perturbation series for the eigenfunctions and the eigenvalues directly
by knowing the eigenfunctions and the eigenvalues of the unperturbed problems in quantum mechanics. Examples are presented
to support this. Hence, the LDE technique can be used for nonperturbative as well as perturbative systems to find approximate
solutions of eigenvalue problems. 相似文献
9.
S.K. SAHUP.K. DATTA 《Journal of sound and vibration》2002,251(4):683-696
The parametric instability behaviour of curved panels with cutouts subjected to in-plane static and periodic compressive edge loadings are studied using finite element analysis. The first order shear deformation theory is used to model the curved panels, considering the effects of transverse shear deformation and rotary inertia. The theory used is the extension of dynamic, shear deformable theory according to Sanders' first approximation for doubly curved shells, which can be reduced to Love's and Donnell's theories by means of tracers. The effects of static and dynamic load factors, geometry, boundary conditions and the cutout parameters on the principal instability regions of curved panels with cutouts are studied in detail using Bolotin's method. Quantitative results are presented to show the effects of shell geometry and load parameters on the stability boundaries. Results for plates are also presented as special cases and are compared with those available in the literature. 相似文献
10.
The multiplicity fluctuations of the produced pions were studied using scaled variance method in 16O–AgBr interactions at 2.1 AGeV, 24Mg–AgBr interactions at 4.5 AGeV, 12C–AgBr interactions at 4.5 AGeV, 16O–AgBr interactions at 60 AGeV and 32S–AgBr interactions at 200 AGeV at two different binning conditions. In the first binning condition, the rapidity interval
was varied in steps of one centring about the central rapidity until it reached 14. In the second case, the rapidity interval
was increased in steps of 1.6 up to 14.4. Multiplicity distributions and their scaled variances were presented as a function
of the dependence on the rapidity width for both the binning conditions. Multiplicity fluctuations were found to increase
with the increase of rapidity interval and later found to saturate at larger rapidity window for all the interactions and
in both the binning conditions. Multiplicity fluctuations were found to increase with the energy of the projectile beam. The
values of the scaled variances were found to be greater than one in all the cases in both the binning conditions indicating
the presence of correlation during the multiparticle production process in high-energy nucleus–nucleus interactions. Experimental
results were compared with the results obtained from the Monte Carlo simulated events for all the interactions. The Monte
Carlo simulated data showed very small values of scaled variance suggesting very small fluctuations for the simulated events.
Experimental results obtained from 16O–AgBr interactions at 60 AGeV and 32S–AgBr interactions at 200 AGeV were compared with the events generated by Lund Monte Carlo code (FRITIOF model). FRITIOF
model failed to explain the multiplicity fluctuations of pions emitted from 16O–AgBr interactions at 60 AGeV for both the binning conditions. However, the experimental data agreed well with the FRITIOF
model for 32S–AgBr interactions at 200 AGeV. 相似文献