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91.
In this study, in situ control growth of bismuth nanoparticles (Bi0 NPs) was demonstrated in bismuth-based glass dielectrics under an electron beam (EB) irradiation at room temperature. The
effects of EB irradiation were investigated in situ using transmission electron microscopy (TEM), selected-area electron diffraction
and high-resolution transmission electron microscopy. The EB irradiation for 2–8 min enhanced the construction of bismuth
nanoparticles with a rhombohedral structure and diameter of 4–9 nm. The average particle size was found to increase with the
irradiation time. Bismuth metal has a melting point of 271 °C and this low melting temperature makes easy the progress of
energy induced structural changes during in situ TEM observations. This is a very useful technique in nano-patterning for
integrated optics and other applications. 相似文献
92.
Arijit Das Eric Soehnlen Stephan Woods Ravi Hegde Amanda Henry Arne Gericke Soumitra Basu 《Journal of nanoparticle research》2011,13(12):6283-6290
We report a novel gold nanobioconjugate system that achieves targeted delivery of the small molecule drug doxorubicin to endothelial
cells using anti-VEGFR-2 antibody conjugated gold nanoparticles (GNPs). The reported nanobioconjugate system combines the
inherent ability of GNPs to undergo high levels of derivatization with the precision of antibody recognition of a cell surface
antigen. Transmission electron microscopy (TEM) and surface-enhanced Raman spectroscopy (SERS) confirmed intracellular presence
of the GNPs. Using a VEGFR-2 expressing cell line and a cell line that is negative for the receptor, in combination with competition
assay we established the cell specific targeted delivery of the nanobioconjugate. The nanobioconjugate system described here
may have potential drug delivery applications for antiangiogenic cancer therapy. 相似文献
93.
T. R. Routray S. K. Tripathy B. B. Dash B. Behera D. N. Basu 《The European Physical Journal A - Hadrons and Nuclei》2011,47(8):92
The half-lives of proton radioactivity of proton emitters are investigated theoretically. Proton-nucleus interaction potentials
are obtained by folding the densities of the daughter nuclei with a finite-range effective nucleon-nucleon interaction having
Yukawa form. The Wood-Saxon density distributions for the nuclei used in calculating the nuclear as well as the Coulomb interaction
potentials are predictions of the interaction. The quantum mechanical tunneling probability is calculated within the WKB framework.
These calculations provide reasonable estimates for the observed proton radioactivity lifetimes. The effects of neutron-proton
effective mass splitting in neutron-rich asymmetric matter as well as the nuclear matter incompressibility on the decay probability
are investigated. 相似文献
94.
A. Basu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,61(1):51-55
Electron-hydrogen scattering has been investigated in
Debye plasma environment employing the close-coupling approximation. Two
models, viz., 6-state CCA and 9-state CCA have been used. Plasma screening
has been taken into account via Debye-Hückel model potential. The
lowest lying 1De^1{\rm D}^{{\rm e}} auto-detaching resonance of the hydrogen negative
ion has been successfully predicted for various plasma conditions. The
resonant state changes to shape resonance for Debye scattering lengths less
than a critical value. 相似文献
95.
We study different correlation functions for a spin imbalanced and harmonically trapped Fermi gas in two dimensions described by an attractive Hubbard model. Eigensolutions obtained via numerically solving Bogoliubov de Gennes equations are used to compute the local pairing amplitudes which show significantly different behaviour for the trapped case where the profile is radially modulated in contrast with a spatial modulation extending throughout the lattice geometry when trap effects are switched off. Further, different experimentally accessible quantities, such as pair–pair, density–density correlations and local density fluctuations show characteristic fluctuations for the spin polarized phase, which however wash away as the trapping effects are turned on. A contrasting scenario is presented corresponding to the case when the spin polarization effects are turned off. 相似文献
96.
The occurrence of similar structural repeats in a protein structure has evolved through gene duplication. These repeats act as a structural building block and form more than one compact structural and functional unit called a repeat domain. The protein families comprising similar structural repeats are mainly involved in protein–protein interactions as well as binding to other ligand molecules. The identification of internal sequence repeats in the primary structure is not sufficient for the analysis of structural repeats. Thus, a new method called ProSTRIP has been developed using dynamic programming to find the similar structural repeats in a three-dimensional protein structure. The detection of these repeats is made by calculating the protein backbone Cα angles. An internet computing server is also created by implementing this method and enables graphical visualization of the results. It can be freely accessed at http://cluster.physics.iisc.ernet.in/prostrip/. 相似文献
97.
Goutam Mukhopadhyay Jasmina Khanam Arunabha Nanda Arindam Basu Sarkar 《Chromatographia》2010,71(7-8):699-702
A simple, sensitive and precise reverse phase liquid chromatographic method has been developed and validated for quantification of bovine serum albumin (BSA), α-lactalbumin (α-La) and β–lactoglobulin (β-Lg) that are removed from whey waste by foam fractionation method. The data is reproducible over a wide concentration range. This optimized method allowed analysis of BSA, α-La, β-Lg in a mixture within 5 min and could be applied to the analysis of a variety of commercial and laboratory whey products within a short time. 相似文献
98.
99.
100.
D. P. Bhattacharyya R. Rakshit B. Basu P. Pal S. Biswas N. Durgaprasad 《Il Nuovo Cimento C》1992,15(3):341-347
Summary A search has been made on the charge-changing partial cross-sections by using 0.927 GeV/n238U ion from LBL BEVALAC projected at an angle 30° on27Al target and CR-39 (DOP) was used as analyser. The irradiated plastic sheets were duly etched for one hour in 6.25N NaOH
solution and about 1680 cone lengths at both the surfaces of the CR-39 (DOP) sheets were optically measured. The cone length
distribution exhibits the existence of U fragments in the charge range 84≤Z≤91 and the estimated partial cross-sections range from 60 to 400 mb. The present data are in accord with the fit to the extrapolated
data of Binnset al. 相似文献