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81.
It has been found that the states of the 2-charge extremal D1–D5 system are given by smooth geometries that have no singularity and no horizon individually, but a ‘horizon’ does arise after ‘coarse-graining’. To see how this concept extends to the 3-charge extremal system, we construct a perturbation on the D1–D5 geometry that carries one unit of momentum charge P. The perturbation is found to be regular everywhere and normalizable, so we conclude that at least this state of the 3-charge system behaves like the 2-charge states. The solution is constructed by matching (to several orders) solutions in the inner and outer regions of the geometry. We conjecture the general form of ‘hair’ expected for the 3-charge system, and the nature of the interior of black holes in general. 相似文献
82.
S. Gopal C. Viswanathan M. Thamilselvan K. Premnazeer Sa. K. Narayandass D. Mangalaraj 《Ionics》2004,10(3-4):300-303
Indium Selenide thin films were electrodeposited on Indium Tin Oxide (ITO) coated glass substrates from a mixture of Indium
trichloride (InCl3) and selenium dioxide (SeO2) in aqueous solution by the potentiostatic electrodeposition technique. The InSe films showed that Mott’s variable-range
hopping conductivity (VRH) is dominant under low field (∼2×105 Vcm−1) condition. At high field the Current-Voltage studies (in the temperature range 300 – 380 K) revealed that the conductivity
of Indium selenide thin films is of Poole-Frenkel type. The plot drawn between Ln (I/V) and tV showed a straight line and
also the experimental data and the theoretical data closely matches. Hence Poole-Frenkel mechanism is confirmed and discussed
in detail.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
83.
A. Bhattacharya A. Chandra B. Chakraborti 《International Journal of Theoretical Physics》2012,51(1):206-212
The mass splitting and the decay width of pentaquark (Θ+) at the higher angular momentum states have been investigated in the framework of flux tube model considering the diquark-diquark-antiquark configuration for Θ+ along with statistical model. A quasi particle model for diquark has been considered. The Regge trajectory of Θ+ has also been investigated with interesting some observations. 相似文献
84.
Adamson P Andreopoulos C Arms KE Armstrong R Auty DJ Ayres DS Baller B Barr G Barrett WL Becker BR Belias A Bernstein RH Bhattacharya D Bishai M Blake A Bock GJ Boehm J Boehnlein DJ Bogert D Bower C Buckley-Geer E Cavanaugh S Chapman JD Cherdack D Childress S Choudhary BC Coleman SJ Culling AJ de Jong JK Diwan MV Dorman M Dytman SA Escobar CO Evans JJ Falk Harris E Feldman GJ Frohne MV Gallagher HR Goodman MC Gouffon P Gran R Grashorn EW Grossman N Grzelak K Habig A Harris D Harris PG 《Physical review letters》2008,101(15):151601
A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in the standard-model extension lie between 10(-4) and 10(-2) of the maximum expected, assuming a suppression of these signatures by a factor of 10(-17). 相似文献
85.
S. Ganguly Aparajita Dey P. Banerjee S. Bhattacharya R. P. Singh S. Muralithar R. Kumar R. K. Bhowmik 《Brazilian Journal of Physics》2011,41(2-3):135-139
Excited states of 83Kr, populated in the 76Ge(11B, 3npγ) reaction at a beam energy of 50 MeV, have been studied. The ΔI?=?1 band, built upon the 2,510.0 keV state, has been observed up to 5,639.4 keV with spin (27/2???). Mean lifetimes have been measured up to spin 23/2?? in ΔI?=?1 band using the Doppler shift attenuation method. The B(M1) rates derived from the measured lifetimes decrease smoothly with spin indicating that the angular momentum belonging to this band are generated by the shears mechanism. 相似文献
86.
The study of protein conformational changes in the presence of surfactants and lipids is important in the context of protein
folding and misfolding. In the present study, we have investigated the mechanism of the protein conformational change coupled
with aggregation leading to size growth of Hen Egg White Lysozyme (HEWL) in the presence of an anionic detergent such as sodium
dodecyl sulphate (SDS) in alkaline pH. We have utilized intrinsic protein fluorescence (tryptophan) and extrinsic fluorescent
reporters such as 8-anilinonaphthalene-1-sulfonic acid (ANS), dansyl and fluorescein to follow the protein conformational
change in real-time. By analyzing the kinetics of fluorescence intensity and anisotropy of multiple fluorescent reporters,
we have been able to delineate the mechanism of surfactant-induced aggregation of lysozyme. The kinetic parameters reveal
that aggregation proceeds with an initial fast-phase (conformational change) followed by a slow-phase (self-assembly). Our
results indicate that SDS, below critical micelle concentration, induces conformational expansion that triggers the aggregation
process at a micromolar protein concentration range. 相似文献
87.
Dipsikha Bhattacharya Sumanta K. Sahu Indranil Banerjee Manasmita Das Debashish Mishra Tapas K. Maiti Panchanan Pramanik 《Journal of nanoparticle research》2011,13(9):4173-4188
In this article, we report the design and synthesis of a series of well-dispersed superparamagnetic iron oxide nanoparticles
(SPIONs) using chitosan as a surface modifying agent to develop a potential T
2 contrast probe for magnetic resonance imaging (MRI). The amine, carboxyl, hydroxyl, and thiol functionalities were introduced
on chitosan-coated magnetic probe via simple reactions with small reactive organic molecules to afford a series of biofunctionalized
nanoparticles. Physico-chemical characterizations of these functionalized nanoparticles were performed by TEM, XRD, DLS, FTIR,
and VSM. The colloidal stability of these functionalized iron oxide nanoparticles was investigated in presence of phosphate
buffer saline, high salt concentrations and different cell media for 1 week. MRI analysis of human cervical carcinoma (HeLa)
cell lines treated with nanoparticles elucidated that the amine-functionalized nanoparticles exhibited higher amount of signal
darkening and lower T
2 relaxation in comparison to the others. The cellular internalization efficacy of these functionalized SPIONs was also investigated
with HeLa cancer cell line by magnetically activated cell sorting (MACS) and fluorescence microscopy and results established
selectively higher internalization efficacy of amine-functionalized nanoparticles to cancer cells. These positive attributes
demonstrated that these nanoconjugates can be used as a promising platform for further in vitro and in vivo biological evaluations. 相似文献
88.
We demonstrate a method of generating short pulses at 1350 nm by exciting Cerenkov radiation in a higher-order-mode fiber with a 1064 nm femtosecond fiber laser. We measure a 106 fs, 0.66 nJ output pulse. Cerenkov radiation in fibers allows for energy transfer between a soliton and a dispersive wave, providing an effective and engineerable platform to shift the wavelength of a femtosecond source. With appropriate design of the higher-order-mode fiber, this method of generating short pulses at 1350 nm can be extended to other wavelengths and to higher pulse energies. 相似文献
89.
90.
The electrical, structural, and photoelectrochemical properties of the polymer electrolyte PEO:NaI/I2 doped with an ionic liquid 1-ethyl 3-methylimidazolium dicyanamide (EMImDCN) have been reported. Incorporation of the ionic
liquid (IL) increases the membrane homogeneity, decreased surface roughness, and enhances the short current (J
sc). Additionally, the doping of IL provides more charge carriers which enhances overall ionic conductivity (σ). The optimized
σ was found at 40 wt.% IL composition. The fabricated DSSC using this new solid electrolyte showed 1.43% efficiency at 100 mW
cm−2. 相似文献