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101.
102.
Abhijit Bhattacharyya Sanjay K. Ghosh Ritam Mallick Sibaji Raha 《Indian Journal of Physics》2010,84(12):1759-1763
We have studied the v+ $
\bar \nu
$
\bar \nu
→ e
+ + e
− energy deposition rate near a rotating compact star which is important for the study of gamma ray bursts (GRB). The General
relativistic (GR) and rotational effects increase the efficiency of the process immensely. The rotational effect also brings
about an asymmetry in the deposition rate of the star. 相似文献
103.
Kaushik Mallick Michael Witcomb André Strydom 《Applied Physics A: Materials Science & Processing》2012,109(3):607-611
Polymer-stabilized paramagnetic and fluorescent rare-earth metal sulfide (cerium sulfide, Ce2S3) nanoparticles have been synthesized by using an ??in situ polymerization and composite formation?? (IPCF) technique (Mallick et al. in J. Appl. Phys. 106:074303, 2009) at room temperature. Encapsulated cerium sulfide nanoparticles showed photoluminescence when excited with laser irradiation. The composite material exhibited a paramagnetic behavior due to the in situ formation of magnetic Ce3+ ionic species at the reaction condition. 相似文献
104.
An open quantum system interacting with its environment can be modeled under suitable assumptions as a Markov process, described by a Lindblad master equation. In this work, we derive a general set of fluctuation relations for systems governed by a Lindblad equation. These identities provide quantum versions of Jarzynski-Hatano-Sasa and Crooks relations. In the linear response regime, these fluctuation relations yield a fluctuation-dissipation theorem (FDT) valid for a stationary state arbitrarily far from equilibrium. For a closed system, this FDT reduces to the celebrated Callen-Welton-Kubo formula. 相似文献
105.
Anshuman Chutani Suresh P. Sethi 《Journal of Optimization Theory and Applications》2012,154(2):615-643
Cooperative advertising is an incentive offered by a manufacturer to influence retailers’ promotional decisions. We study a dynamic durable goods duopoly with a manufacturer and two independent and competing retailers. The manufacturer, as a Stackelberg leader, announces his wholesale prices and his shares of retailers’ advertising costs, and the retailers in response play a Nash differential game in choosing their optimal retail prices and advertising efforts over time. We obtain the feedback equilibrium policies for the manufacturer and the retailers in explicit form for a linear demand formulation. We investigate issues, like channel coordination and antidiscriminatory legislation, and also study a case, when the manufacturer sells through only one retailer and the second retailer sells a competing brand. 相似文献
106.
Adsorption of hexavalent chromium on manganese nodule leached residue obtained from NH3-SO2 leaching
Adsorption of hexavalent chromium onto manganese nodule leached residues was investigated as a possible alternative to the conventional methods of its removal from aqueous synthetic solutions. Adsorption behavior was studied as a function of time, pH, temperature, and concentration of adsorbate and adsorbent in acetic acid-sodium acetate buffer medium. Cr (VI) removal was pH dependent and was found to be of a maximum at pH 3. The applicability of the Langmuir isotherm to the present system was tested. Increased adsorption capacity with increased temperature indicates that the adsorption reaction was endothermic in nature. Based on these studies, thermodynamic parameters such as Gibbs free energy change (DeltaG0), standard enthalpy change (DeltaH0), and standard entropy change (DeltaS0) were calculated. 相似文献
107.
The surface of ZnS and PbS has been modified by interfacing PbS on ZnS and ZnS on PbS nanoparticles. This produced core-shell nanocomposites ZnS/PbS and PbS/ZnS with tunable electronic properties. In both structures PbS particles are present in cubic form with an average diameter of about 6 nm. The addition of Pb2+ (3 x 10(-4) mol dm(-3)) to Q-ZnS (1.5 x 10(-4) mol dm(-3)) in the basic pH range produces size-quantized fluorescent PbS particles coated by metal hydroxides. In these particles the relaxation kinetics of charge carriers has been followed using a picosecond single-photon counting technique. At 1.5 x 10(-4) mol dm(-3) Pb2+ an interfacial relaxation of charge from ZnS to PbS phase could be observed in subnanosecond time domain. An increase in [Pb2+] from 2 x 10(-4) to 1 x 10(-3) mol dm(-3) enhanced the average emission lifetime from 9.4 to 19.4 ns. Composite PbS/ZnS particles are produced at high [ZnS] only. These particles had emission lifetime in mus time range. The extent of charge separation and the dynamics of charge carriers could be manipulated by the surface modification of these nanostructures. 相似文献
108.
Mallick A Mandal MC Haldar B Chakrabarty A Das P Chattopadhyay N 《Journal of the American Chemical Society》2006,128(10):3126-3127
Tuning of the sensory capability of a potentially bioactive indoloquinolizine system, namely, 3-acetyl-4-oxo-6,7-dihydro-12H-indolo-[2,3-a]-quinolizine (AODIQ), is described in a biomimicking micellar nanocage. It has been shown that surfactant concentration dictates the sensing behavior of the fluorophore toward physiologically essential trace metals, such as Cu2+. This is a simple, efficient, and general technique that allows one to utilize the sensor to its maximum efficiency. 相似文献
109.
110.
Subhasis Mallick Subala Mondal Biplab K. Bera Parnajyoti Karmakar Sankar C. Moi Alak K. Ghosh 《Transition Metal Chemistry》2010,35(4):469-475
The kinetics of the interaction between thiourea and the title complex has been studied spectrophotometrically in aqueous
medium as a function of nucleophile concentration, temperature and pH at constant ionic strength. The reaction is a two-step
process in which the first step is ligand dependent, but the second step is ligand independent and is assigned to ring closure.
The rate and activation parameters, conductivity studies and IR data were used to deduce a plausible mechanism. 相似文献