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111.
In the present work, it is shown that a chameleon scalar field having a non-minimal coupling with dark matter can give rise
to a smooth transition from a decelerated to an accelerated phase of expansion for the Universe. It is surprising to note
that the coupling with the chameleon scalar field hardly affects the evolution of the dark matter sector, which still redshifts
as a
⃛. 相似文献
112.
113.
Chunfeng Huang Tailen Hsing Noel Cressie Auroop R. Ganguly Vladimir A. Protopopescu Nageswara S. Rao 《商业与工业应用随机模型》2010,26(4):331-348
We consider a network of sensors that measure the intensities of a complex plume composed of multiple absorption–diffusion source components. We address the problem of estimating the plume parameters, including the spatial and temporal source origins and the parameters of the diffusion model for each source, based on a sequence of sensor measurements. The approach not only leads to multiple‐source detection, but also the characterization and prediction of the combined plume in space and time. The parameter estimation is formulated as a Bayesian inference problem, and the solution is obtained using a Markov chain Monte Carlo algorithm. The approach is applied to a simulation study, which shows that an accurate parameter estimation is achievable. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
114.
Kakali De Susmita Chandra Bhart Sarkar Santanu Ganguly Mridula Misra 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):621-628
In the recent years interests on dihydropyrimidinone and their analogues have increased potentially due to their wide range
of pharmacological/biological activities. Synthesis, radiolabeling with technetium-99 m (99mTc) and biological evaluation of 5-etoxycarbonyl-4-phenyl-6-methyl-3,4-dihydro-(1H)-pyrimidine-2-one (DHPM) were studied in
this present work. After synthesis complexation of DHPM with 99mTc was carried out using stannous chloride as the reducing agent. The complex (99mTc-DHPM) was characterized by thin layer chromatography, radio-HPLC technique and determination of partition co-efficient.
Radiochemical stability and particle size distribution of the complex were also measured. Biodistribution/scintigraphy studies
were performed in rats and rabbits to evaluate the pharmacological characteristics of this complex. The radiochemical purity
of the complex was over 95% as studied by thin layer chromatography and radio-HPLC. It was stable over 24 h at room temperature.
Its partition coefficient indicated that it was a lipophilic complex. According to the European Pharmacopeia, >80% of 99mTc labeled radiopharmaceutical (99mTc-MAA) in the size range 10–50 μm, must be accumulated in the lungs 15 min after intravenous administration. In this study
>85% of the 99mTc-DHPM complex in the average size of 40 μm. Biodistribution studies of 99mTc-DHPM in rat revealed that the complex accumulated in the lung with high uptake and good retention after intravenous administration.
Scintigraphic studies in rabbit also revealed that most of the administered radiolabeled complex was accumulated in the lungs
and after 1 h slowly excreted through the renal system. The lung uptake (ID%/g) was 10.12, 9.67, 8.60 and 5.01 and the lung/liver
ratio was 7.49, 2.88, 2.62 and 1.87 at 2, 15, 30 and 60 min post-injection, respectively. These results suggested that 99mTc-DHPM could be suitable as a potential lung perfusion imaging agent. Further studies with 99mTc-DHPM and its derivatives are warranted to develop new 99mTc-labeled imaging agents for clinical applications. 相似文献
115.
The general solution of the stationary Schrödinger equation for the associated Lamé potentials with an arbitrary real energy is found. The supersymmetric partners are generated by employing seed solutions for factorization energies inside the gaps. 相似文献
116.
Stuart W. McCombie Bandarpalle B. Shankar Ashit K. Ganguly 《Tetrahedron letters》1985,26(51):6301-6304
E-2-(Phenylsulfonyl)vinyl ethers of 2,3-epoxyalcohols are stereospecifically rearranged to 3-(phenylsulfony])-4-(1-hydroxyalkyl)-4,5-dihydrofurans on treatment with LDA. Oxidation of these compounds or the derived des-sulfonyl compounds provides esters or lactones which correspond to regiospecific delivery of -CO2H or -CH2CO2H to C-2, with inversion. 相似文献
117.
The geometries of the two H–O–C rotamers of synand two of anti-7-norbornenol have been optimized at the ab initio HF/6-31G** and B3LYP hybrid HF-DFT levels of theory by using a 6-31G** basis set. Contrary to an earlier report, we find that the (nongeometry constrained) anti-trans isomer (1d) is predicted to be more stable than the corresponding syn-cis form (1a). The increased stability of 1d
vis-à-vis
1a can be accounted for in terms of relative H(1)–C(2)–O(3)–H(4) torsion energy effects. The computational results indicate that the hydroxyl proton in 1a enters into intramolecular hydrogen bonding with the proximate C=C bond. Supporting evidence for this conclusion resides in the fact that the 1a is predicted to possess the lowest O–H stretching frequency, a result that can be attributed to -hydrogen bonding. 相似文献
118.
P. C. Srivastava B. N. Singh S. K. Ghosh N. C. Ganguly 《Journal of Thermal Analysis and Calorimetry》1986,31(5):1153-1160
A binuclear copper(II)—urea complex was synthesized and its structure was established from elemental analyses, IR, UV and visible spectroscopy and magnetic susceptibility measurements to be [OC(NH2)2Cu(OH)2]2. The kinetics of the thermal decomposition of the complex were studied by recording thermogravimetric measurements in streams of nitrogen and oxygen. TG analysis showed three main steps of decomposition, leading to Cu2O formation in the final stage. 相似文献
119.
120.
Quasi two-dimensional copper oxides derived from La1·8Sr0·2CuO4 by substitution of La, Sr or Cu show highT
c
superconductivity.
Contribution No. 421 from the Solid State and Structural Chemistry Unit. 相似文献