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151.
Two new fluorescent BODIPY dyes have been designed and synthesized. They dyes differ in their meso substituents, which have different electronic properties. Their selective reactivity towards an Ar‐SN2 reaction has been explored as a potential basis for colorimetric and fluorescent discrimination of primary, secondary and tertiary aliphatic amines. This dual‐mode, instantaneous recognition event is unprecedented. 相似文献
152.
Anirbandeep Bose Uttam Bhaumik Animesh Ghosh Bappaditya Chatterjee Uday Sankar Chakrabarty Amlan Kanti Sarkar Tapan Kumar Pal 《Chromatographia》2009,69(11-12):1233-1241
A rapid, simple, sensitive and specific liquid chromatography–tandem mass spectrometry method was developed and validated for simultaneous quantification of itopride hydrochloride and domperidone in human plasma. Both drugs were extracted by liquid–liquid extraction with ethyl acetate and saturated borax solution. The chromatographic separation was performed on a reversed-phase C18 column with a mobile phase of water–methanol (2:98, v/v) containing 0.5% formic acid. The protonated analyte was quantitated in positive ionization by multiple reaction monitoring with a mass spectrometer. The assay exhibited linearity over the concentration range of 3.33–500 ng mL?1 for itopride hydrochloride and 3.33–100 ng mL?1 for domperidone in human plasma. The precursor to product ion transitions of m/z 359.1–72.3 and 426.0–147.2 were used to measure itopride hydrochloride and domperidone respectively. The method was found suitable for the analysis of plasma samples collected during phase 1 pharmacokinetics study of itopride HCl 50 mg and domperidone 20 mg in 12 healthy volunteers after single oral doses of the combination drug. 相似文献
153.
It is the purpose of this paper to model the retailer’s profit-maximizing strategy when confronted with supplier’s trade offer of credit and price-discount on the purchase of merchandise. Generally, retailers have to face many types of demands for different kinds of goods. In real situation, retailers have to correlate between the selling price and supplier’s trade offer, keeping in mind profit-maximization strategy. In the proposed model, all increasing deterministic demands are discussed analytically, numerically and graphically in the environment of permissible delay in payment and discount offer to the retailer. 相似文献
154.
155.
Papia Chowdhury Tirtha Pratim Adhikary Sankar Chakravorti 《Journal of luminescence》2008,128(7):1113-1120
In this paper, an interesting transformation of the emission of anionic conformer of 2-benzoyl bezimidazole in ionic and non-ionic micelles is reported. Deprotonation is hindered in cationic and non-ionic micelles owing to probe molecule's passage deep inside positive ion-rich Stern-layer in contrast with anionic micelle. The orientation of probe molecule in the two ionic micelles, as determined from the spectral properties is opposite in nature. Micellar environment shields the formation of mono- and di-cationic species at very low pH. Three decay times of the probe in different time domains were attributed to three possible anionic species and they are modified differently in ionic and neutral micelles. Quantum chemical calculations also predict the existence of three different possible anionic species. 相似文献
156.
Robert Gruar Christopher James Tighe Lee M. Reilly Gopinathan Sankar Jawwad Arshad Darr 《Solid State Sciences》2010,12(9):1683-1686
Herein, we report the rapid single step hydrothermal synthesis of phase pure Bi2MoO6 (koechlinite) and Bi2Mo3O12, via a continuous hydrothermal flow synthesis (CHFS) reactor, which uses supercritical water of 375–450 °C at a pressure of 24.1 MPa as a crystallising medium. The product being obtained as highly crystalline nano-materials with high surface area. Simple variation in synthesis condition and appropriate solution stoichiometry were shown to be sufficient to select the phase of the product. The materials synthesised showed significant photcatalytic activity towards the decolourisation of methylene blue in comparison to a commercial gold standard photocatalyst. 相似文献
157.
Bipin Singh Koranga Mohan Narayan S. Uma Sankar 《International Journal of Theoretical Physics》2011,50(5):1515-1521
The recent measurement of Δ
sol
by the KamLAND experiment with very small errors, makes definitive predictions for the energy dependence of the solar neutrino
survival probability P
ee
. We fix Δ
sol
to be the KamLAND best fit value of 8×10−5 eV2 and study the energy dependence of P
ee
for solar neutrinos, in the framework of two flavour oscillations and also of three flavour oscillations. For the case of
two flavour oscillations, P
ee
has a measurable slope in the 5–8 MeV range but the solar spectrum measurements in this range find P
ee
to be flat. The predicted values of P
ee
, even for the best fit value of θ
sol
, differ by 2–3 σ from the Super-K measured values in each of the three energy bins of the 5–8 MeV range. If future measurements of solar neutrinos
by Super-K and SNO find a flat spectrum with reduced error bars (by a factor of 2), it will imply that two flavour oscillations
can no longer explain both KamLAND data and the solar spectrum. However a flat solar neutrino spectrum and the Δ
sol
measured by KamLAND can be reconciled in a three flavour oscillation framework with a moderate value of θ
13≈13°. 相似文献
158.
Okada Y Dhital C Zhou W Huemiller ED Lin H Basak S Bansil A Huang YB Ding H Wang Z Wilson SD Madhavan V 《Physical review letters》2011,106(20):206805
We study interference patterns of a magnetically doped topological insulator Bi(2-x)Fe(x)Te(3+d) by using Fourier transform scanning tunneling spectroscopy and observe several new scattering channels. A comparison with angle-resolved photoemission spectroscopy allows us to unambiguously ascertain the momentum-space origin of distinct dispersing channels along high-symmetry directions and identify those originating from time-reversal symmetry breaking. Our analysis also reveals that the surface state survives far above the energy where angle-resolved photoemission spectroscopy finds the onset of continuum bulk bands. 相似文献
159.
We present a natural framework for studying the persistence problem in two-dimensional fluid turbulence by using the Okubo-Weiss parameter Λ to distinguish between vortical and extensional regions. We then use a direct numerical simulation of the two-dimensional, incompressible Navier-Stokes equation with Ekman friction to study probability distribution functions (PDFs) of the persistence times of vortical and extensional regions by employing both Eulerian and Lagrangian measurements. We find that, in the Eulerian case, the persistence-time PDFs have exponential tails; by contrast, this PDF for Lagrangian particles, in vortical regions, has a power-law tail with an exponent θ=2.9±0.2. 相似文献
160.
Basak R Mukhopadhyay N Bandyopadhyay R 《The European physical journal. E, Soft matter》2011,34(9):103
Photon correlation spectroscopy and rheological measurements are performed to investigate the microscopic dynamics and mechanical
responses of aqueous solutions of triblock copolymers and aqueous mixtures of triblock copolymers and anionic surfactants.
Increasing the concentration of triblock copolymers results in a sharp increase in the magnitude of the complex moduli characterising
the samples. This is understood in terms of the changes in the aggregation and packing behaviours of the copolymers and the
constraints imposed upon their dynamics due to increased close packing. The addition of suitable quantities of an anionic
surfactant to a strongly elastic copolymer solution results in a decrease in the complex moduli of the samples by several
decades. It is argued that the shape anisotropy and size polydispersity of the micelles comprising mixtures cause dramatic
changes in the packing behaviour, resulting in sample unjamming and the observed decrease in complex moduli. Finally, a phase
diagram is constructed in the temperature-surfactant concentration plane to summarise the jamming-unjamming behaviour of aggregates
constituting triblock copolymer-anionic surfactant mixtures. 相似文献