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101.
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
102.
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
103.
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
104.
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
105.
106.
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
107.
K. Mallick M.J. Witcomb M.S. Scurrell 《Applied Physics A: Materials Science & Processing》2005,80(4):797-801
The objective of this study is to investigate the elementary mechanism of the formation of nanoclusters in terms of the various stages involved, viz. atom formation, cluster nucleation and growth. The thermodynamics of their reaction where the clusters play an efficient role as a catalyst for the redox system is also another interesting dimension of the study. Synthesis of particles suggests a two-step process, i.e. nucleation and successive growth. The atoms agglomerate to form metal clusters. A metal cluster acting as a catalytic relay behaves alternately as an acceptor and as a donor of electrons. An effective transfer of electrons is possible when the potential of the cluster is more positive than that of the electron-donor system. PACS 87.20.Dd; 81.16.Hc; 81.07.-b; 78.67.-n; 82.35.Np 相似文献
108.
Madhuja Mallick Nalini Ravishanker 《Methodology and Computing in Applied Probability》2006,8(4):541-558
In this article, we describe an additive stable frailty model for multivariate times to events data using a flexible baseline
hazard, and assuming that the frailty component for each individual is described by additive functions of independent positive
stable random variables with possibly different stability indices. Dependence properties of this frailty model are investigated.
To carry out inference, the likelihood function is derived by replacing high-dimensional integration by Monte Carlo simulation.
Markov chain Monte Carlo algorithms enable estimation and model checking in the Bayesian framework.
相似文献
109.
110.
Sankha Chattopadhyay Luna Barua Sujata Saha Das Anirban De Umesh Kumar Arpit Mitra Tapas Mallick Madhusmita Md. Alam Nayer Samarendu Sinha Bharat Ratna Sarkar Shantanu Ganguly Kakali De Malay Kanti Das M. G. R. Rajan 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):781-790
Performance study of a computer controlled automated closed cyclic module for the separation and recovery of 99mTc from low specific activity (n, γ) 99Mo using methyl ethyl ketone (MEK) solvent extraction technique named 99Mo/99mTc-TCM-AUTOSOLEX (Technetium automated solvent extraction) Generator is described. The entire system is automated and controlled by a user-friendly PC based graphical user interface that actually supervises process via an embedded system based electronic controller. The average yield of separation of 99mTc was above 85 % and 99Mo breakthrough in 99mTc pertechnetate was <0.002 %. The sodium pertechnetate obtained was a clear solution having pH 6–7, Radiochemical (RC). Purity >99 %, MEK content <0.1 % (v/v), Al and Mo content <10 µg/ml. R. C. Purity of 99mTc-radiopharmaceuticals studied was not less than 96 %. Bio-Quality control studies confirm that sodium pertechnetate obtained was sterile and pyrogen free. Imaging studies in animals and humans with limited radiopharmaceuticals show that the quality of 99mTc-pertechenate obtained in the present module was good enough to do clinical study. 相似文献