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111.
Sengupta T Dutta Choudhury S Basu S 《Journal of the American Chemical Society》2004,126(34):10589-10593
The interaction between 2'-deoxyadenosine and the model antitumor drug menadione has been studied in organic solvent and in micellar medium. The aim of the work is to elucidate the mechanism of this drug-nucleoside interaction and to determine the environmental effects. Laser flash photolysis and magnetic field effect are used to detect the transients and their spin states. The results indicate that H atom transfer and electron transfer are the operative mechanisms depending upon the medium. 相似文献
112.
Thomas JM Raja R Johnson BF O'Connell TJ Sankar G Khimyak T 《Chemical communications (Cambridge, England)》2003,(10):1126-1127
Adipic acid (2) production currently entails use and generation of environmentally harmful materials: an efficient catalyst, consisting of nanoparticles of Ru10Pt2 anchored within the pores of mesoporous silica, facilitates the production of (2) by hydrogenating muconic acid, that may be derived biocatalytically from D-glucose. 相似文献
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We present the electron density map of the asymmetric ripple phase of dilauroylphosphatidylcholine. We find that the primary feature characterizing the "asymmetry" of the rippled bilayers is the difference in the bilayer thickness in the two arms, and not the asymmetry of the bilayer height profile as is generally assumed. This difference in the bilayer thickness can be attributed to a mean tilt of the hydrocarbon chains of the lipid molecules along the direction of the ripple wave vector. We propose a Landau theory for this phase which takes into account the anisotropic elastic properties of a bilayer with tilt order. 相似文献
116.
Winfried Kohnen Jyoti Sengupta 《Proceedings of the American Mathematical Society》2000,128(6):1641-1646
We shall give a certain nonvanishing result for the symmetric square -function of an elliptic cuspidal Hecke eigenform w.r.t. the full modular group inside the critical strip.
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Sengupta S Nielaba P Rao M Binder K 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》2000,61(2):1072-1080
Fluctuations of the instantaneous local Lagrangian strain epsilon(ij)(r,t), measured with respect to a static "reference" lattice, are used to obtain accurate estimates of the elastic constants of model solids from atomistic computer simulations. The measured strains are systematically coarse-grained by averaging them within subsystems (of size L(b)) of a system (of total size L) in the canonical ensemble. Using a simple finite size scaling theory we predict the behavior of the fluctuations as a function of L(b)/L and extract elastic constants of the system in the thermodynamic limit at nonzero temperature. Our method is simple to implement, efficient, and general enough to be able to handle a wide class of model systems, including those with singular potentials without any essential modification. We illustrate the technique by computing isothermal elastic constants of "hard" and "soft" disk triangular solids in two dimensions from Monte Carlo and molecular dynamics simulations. We compare our results with those from earlier simulations and theory. 相似文献
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A. Sengupta 《Acta Mathematica Hungarica》1986,48(3-4):347-352
120.
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