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121.
122.
Various substituted imidazo[4,5-b]pyridine analogues of Hoechst 33258 have been synthesized to explore the potential of selective helicase blockade and anticancer activity. The target compounds II a, b & d were obtained by condensation of the appropriate functionalized diamine and substituted benzimidazole aldehydes in nitrobenzene. 相似文献
123.
Nilesh S. Kanhe Sunil U. Tekale Naveen V. Kulkarni Ashok B. Nawale A. K. Das Sudha V. Bhoraskar Rajeeta D. Ingle Rajendra P. Pawar 《Journal of the Iranian Chemical Society》2013,10(2):243-249
The present work reports the application of micron-particulate crystalline hexagonal aluminium nitride/aluminium as a novel, mild acidic and reusable solid heterogeneous catalyst in organic synthesis. The catalyst was synthesized by thermal plasma technique and characterized using X-ray diffractometer and scanning electron microscopy. It catalyzes efficiently many organic transformations such as the synthesis of heterocyclic compounds 2,4,5-triaryl-substituted imidazoles and 2-aryl benzimidazoles. 相似文献
124.
We extend the method of path integrals to obtain the solution of the chiral Schwinger model in curved space-time and compare it with the flat space-time solution. 相似文献
125.
The thermodynamics of general relativistic systems with boundary, obeying a Hamiltonian constraint in the bulk, is determined
solely by the boundary quantum dynamics, and hence by the area spectrum. Assuming, for large area of the boundary, (a) an
area spectrum as determined by non-perturbative canonical quantum general relativity (NCQGR), (b) an energy spectrum that
bears a power law relation to the area spectrum, (c) an area law for the leading order microcanonical entropy, leading thermal
fluctuation corrections to the canonical entropy are shown to be logarithmic in area with a universal coefficient. Since the
microcanonical entropy also has universal logarithmic corrections to the area law (from quantum space-time fluctuations, as
found earlier) the canonical entropy then has a universal form including logarithmic corrections to the area law. This form
is shown to be independent of the index appearing in assumption (b). The index, however, is crucial in ascertaining the domain
of validity of our approach based on thermal equilibrium. 相似文献
126.
Thermal expansion measurements have been carried out on Fe substituted superconducting compounds Y1Ba2(Cu1−x
Fe
x
)3O
y
(0<x<4%) using a high resolution dilatometer employing the three terminal capacitance technique. The experimental set up is sensitive
enough to detect changes in α of less than 10−8K−1. Results show that the jump Δα in the coefficient of linear thermal expansion at the superconducting transition temperature,T
c, increases almost linearly with Fe concentration. The normal state thermal expansion coefficient α first decreases, attains
a minimum value aroundx=1% and then increases for higher Fe concentrations. The oxygen content per unit formula is almost constant up tox=1% and then increases rapidly withx. It has also been observed that the anomalous behaviour of α around 260 K observed by Meingastet al [22] for Fe concentrationx=5% is due to inadequate annealing of the sample. 相似文献
127.
Ashok Kumar Singh Rupam Singh 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):249-255
A poly(vinyl chloride)-based membrane of 3,4:12,13-dibenzo-1,6,10,15-tetraazacyclooctadecane with sodium tetraphenyl borate (NaTPB) as an anion excluder and dibutylphthalate (DBP), dibutylbutylphosphonate (DBBP), tris(2-ethylhexyl) phosphate (TEHP) and tributyl phosphate (TBP) as plasticizing solvent mediator was prepared and investigated as a Ni(II)-selective electrode. The best performance was observed with the membrane having the ligand-PVC-TEHP-NaTPB composition 1:4:1:1, which worked well over a wide concentration range (2.82 ×10−6−1.00 × 10−1 M) with a Nernstian slope of 30.5 mV per decade of activity between pH 2.5–7.5. This electrode showed a fast response time of 18 s and was used over a period of 4 months with good reproducibility (S=0.4 mV). The selectivity coefficient over mono-, di- and trivalent cations indicate excellent selectivity for Ni (II) ions over a large number of cations. Anions such as Cl− and NO3− do not interfere and the electrode also works satisfactorily in a partially non-aqueous medium. It has been used successfully for determination of Ni (II) in real samples. 相似文献
128.
Revisiting Stokes' first problem for Maxwell fluids 总被引:1,自引:0,他引:1
Jordan P. M.; Puri Ashok 《The Quarterly Journal of Mechanics and Applied Mathematics》2005,58(2):213-227
129.
Ashok Razdan 《Pramana》2002,58(3):537-544
In this paper we study Bombay stock exchange (BSE) index financial time series for fractal and multifractal behaviour. We
show that BSE index time series is monofractal and can be represented by a fractional Brownian motion. 相似文献
130.