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81.
Subramanya Gopal Hegde Vijayakumar G. Revanasiddappa Suchetan P. Adimule Suman Y. Reddy Atanu Ghoshal 《合成通讯》2013,43(19):2485-2495
A new julolidine hybrid analogs have been accomplished in a regio and stereo controlled manner using heterogenous MgSiO3 nanoparticles (NPs) catalyzed intramolecular dipolar cycloaddition reaction as a key step. The synthesized catalyst was used in the preparation of various new julolidine analogs with a good yield ranging from 65 to 85%. Further, catalyst could be recycled in several times without loss of significant activity which was an added advantage to the principles of green chemistry. 相似文献
82.
Ghoshal G Luchies AC Blue JP Oelze ML 《The Journal of the Acoustical Society of America》2011,130(4):2203-2211
Quantitative ultrasound (QUS) is an imaging technique that can be used to quantify tissue microstructure giving rise to scattered ultrasound. Other ultrasonic properties, e.g., sound speed and attenuation, of tissues have been estimated versus temperature elevation and found to have a dependence with temperature. Therefore, it is hypothesized that QUS parameters may be sensitive to changes in tissue microstructure due to temperature elevation. Ultrasonic backscatter experiments were performed on tissue-mimicking phantoms and freshly excised rabbit and beef liver samples. The phantoms were made of agar and contained either mouse mammary carcinoma cells (4T1) or chinese hamster ovary cells (CHO) as scatterers. All scatterers were uniformly distributed spatially at random throughout the phantoms. All the samples were scanned using a 20-MHz single-element f/3 transducer. Quantitative ultrasound parameters were estimated from the samples versus increases in temperature from 37 °C to 50 °C in 1 °C increments. Two QUS parameters were estimated from the backscatter coefficient [effective scatterer diameter (ESD) and effective acoustic concentration (EAC)] using a spherical Gaussian scattering model. Significant increases in ESD and decreases in EAC of 20%-40% were observed in the samples over the range of temperatures examined. The results of this study indicate that QUS parameters are sensitive to changes in temperature. 相似文献
83.
Sharma P Chhabra S Rai N Ghoshal N 《Journal of chemical information and modeling》2007,47(3):1087-1096
84.
Umesh Gupta D. Mohan S.K. Ghoshal Vandana Nasa 《Journal of photochemistry and photobiology. A, Chemistry》2010,209(1):7-11
Dynamics related to the optical effect of Methylene Blue (MB) dye molecules in solid host has been investigated. MB doped silica samples of varying concentrations are prepared by the sol–gel technique in acidic environment. Absorption and laser induced fluorescence spectra have been recorded for the samples. Interesting result of dual fluorescence at lower concentrations is explained. Attempt is done to study the dynamics of the dual fluorescence. These results may be useful for designing and developing solid-state optoelectronic devices. 相似文献
85.
86.
Ren C Zhang L Freitas MA Ghoshal K Parthun MR Jacob ST 《Journal of the American Society for Mass Spectrometry》2005,16(10):1641-1653
The acetylated isoforms of histone H4 from mouse lymphosarcoma cells treated with HDAC inhibitors trichostatin A (TSA) and depsipeptide (DDP) were separated by acetic acid urea-polyacrylamide gel electrophoresis (AU-PAGE), in-gel digested, and analyzed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). The acetylation pattern of histone H4 in mouse lymphosarcoma cells induced by TSA was established in which acetylation initially occurred at K16 followed by K12 and then K8 and/or K5. An identical order of acetylation was found for cells treated with DDP. 相似文献
87.
Germanium nanoislands grown by radio frequency magnetron sputtering: Annealing time dependent surface morphology and photoluminescence
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Structural and optical properties of ~ 20 nm Ge nanoislands grown on Si(100) by radio frequency (rf) magnetron sputtering under varying annealing conditions are reported. Rapid thermal annealing at a temperature of 600℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO 2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density (~ 10 11 cm-2 ). The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown (~ 3.29 eV) and annealed (~ 3.19 eV) samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift (~ 0.10 eV) of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics. 相似文献
88.
Swadesh Kumar Ghoshal Sankar Sengupta 《Journal of Quantitative Spectroscopy & Radiative Transfer》1982,27(1):107-108
The Hulburt-Hirschfelder potential function is capable of reproducing a potential hump in the excited 1Σu+ state of the argon dimer, as expected from experimental findings of Tanaka and Yoshino. 相似文献
89.
Summary An attempt is made to study the thermoelectric power of the carriers in quantum well of A
3
II
B
2
V
semiconductors, taking Cd3As2 quantum well as an example. It is found, on the basis of newly derived 2DE−k
s
dispersion relation by including various types of anisotropies in the energy spectrum that the thermoelectric power decreases
with increasing electron concentration and decreasing film thickness respectively. In addition, the corresponding well-known
results for bulk specimens of isotropic parabolic energy bands are also obtained from the expressions derived. 相似文献
90.
We show that matter effects change the numu-->nutau oscillation probability by as much as 70% for certain ranges of energies and path lengths. Consequently, the numu-->nutau survival probability also undergoes large changes. A proper understanding of numu survival rates must consider matter effects in Pmutau as well as Pmue. We comment on (a) how these matter effects may be observed and the sign of Delta31 determined in atmospheric neutrino measurements and at neutrino factories, and (b) how they lead to heightened sensitivity for small theta13. 相似文献