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31.
Detailed structural analysis of the X-Ray diffraction pattern of La0.9Gd0.1FeO3 (LGFO) synthesized via the solid state reaction reveals distorted perovskite structure. Magnetization studies show a characteristic of weak ferromagnetism which is believed to be induced by canted anti-ferromagnetically coupled spins. When explored in a wide temperature and frequency range, AC electrical properties reveal interesting relaxation mechanisms. LGFO exhibits relatively high dielectric permittivity (ε′~4×103) close to room temperature. Temperature dependent magneto-dielectric response appears (magnetodielectric ~−5.5%) even at low magnetic field ~5 kOe. Attractive electrical, magnetic and magnetoelectric properties of the present LGFO at relatively higher temperature makes it a very promising material for application in devices. 相似文献
32.
Zusammenfassung Eine Lösung der Gleichungen der eindimensionalen Plasmaströmung in Anwesenheit eines externen magnetischen Feldes senkrecht zur Strömungsrischtung wird entwickelt im speziellen Fall: (i)P
r
=3/4, (ii)c
p
-constant und (iii)T=T(u). 相似文献
33.
We have made an investigation to study the photodetachment of positronium negative ion (Ps
−) interacting with exponential cosine-screened Coulomb potentials (ECSCP) within the framework of dipole approximation. The
dipole transition matrix elements are calculated using the asymptotic form of highly accurate initial wave function of the
bound ionic state and plane wave for final electron–positronium state. Results for photodetachment cross section in ECSCP
are reported for the screening parameter in the range [0.0,0.35] (in a0-1{a_0^{-1}}). Our results for the unscreened case agree nicely with some of the most accurate results available in the literature. Furthermore
we make a comparative study of the photodetachment of Ps
− in ECSCP with the photodetachment of Ps
− in screened Coulomb potential. To the best of our knowledge, such a study on the photodetachment of Ps
− in ECSCP is carried out for the first time in the literature. 相似文献
34.
Arijit Chakrabarty Gennady Samorodnitsky 《Stochastic Processes and their Applications》2018,128(7):2297-2324
We investigate what happens when an entire sample path of a smooth Gaussian process on a compact interval lies above a high level. Specifically, we determine the precise asymptotic probability of such an event, the extent to which the high level is exceeded, the conditional shape of the process above the high level, and the location of the minimum of the process given that the sample path is above a high level. 相似文献
35.
Kumar Niraj Rodriguez Jassiel R. Pol Vilas G. Sen Arijit 《Journal of Solid State Electrochemistry》2019,23(5):1443-1454
Journal of Solid State Electrochemistry - Here, we present a unique morphology comprising a blend of ultrafine 1D MnO2 and graphene oxide as an efficient anode material to overcome the issue of... 相似文献
36.
Tan G Ford C John VT He J McPherson GL Bose A 《Langmuir : the ACS journal of surfaces and colloids》2008,24(3):1031-1036
The solubilization of phenols in micelles of cetyltrimethyl ammonium bromide leads to microstructural changes from spherical micelles to wormlike micelles and then to vesicles. These microstructures are then used to template silicas. There is a transition from highly ordered hexagonal mesoporous silicas of the M41S family to lamellar structures, as the phenolic dopant concentration is increased. The results have implication to the removal of phenols from aqueous waste streams through the micellar enhanced ultrafiltration process. The entrapment of phenols in mesoporous silicas provides a way to sequester such contaminants in concentrated form. 相似文献
37.
In a quest to track down the origin of coherent vibrational motions observed in femtosecond pump-probe transients, whether they arise from ground/excited electronic state of solute or are contributed by the solvent, we demonstrate a method for extricating vibrations under resonant and non-resonant impulsive excitations using a diatomic solute in condensed phase (iodine in carbon tetrachloride) with aid of spectral dispersion of the chirped broadband probe. Most importantly, we show how a sum over intensities for a select region of detection wavelengths and Fourier transform of data over select temporal window untwine contributions from vibrational modes of different origins. Thus, in a single pump-probe experiment, vibrational features specific to solute as well as solvent are disentangled that are otherwise spectrally overlapping and are non-separable in conventional (spontaneous/stimulated) Raman spectroscopy employing narrowband excitation. We envision wide-ranging applications of this method to unveil vibrational features in complex molecular systems. 相似文献
38.
Segmented conjugated macromolecules containing silicon and boron: ADMET synthesis and luminescent properties 下载免费PDF全文
Arijit Sengupta Ami Doshi Frieder Jäkle Ralf M. Peetz 《Journal of polymer science. Part A, Polymer chemistry》2015,53(14):1707-1718
Boron‐ and silicon‐containing conjugated homo‐ and copolymers could be synthesized using acyclic diene metathesis (ADMET) condensation of bis‐styryl monomers. Both, tri‐and tetra‐coordinated boron monomers were successfully polymerized forming homopolymers, or random copolymers (if polymerized together with a silicon containing co‐monomer). Polymer molecular weights Mn were measured at ~6000 to 15,000 g/mol (NMR end group analysis) with molecular weight distributions Mw/Mn ~1.8 to 2.2. The polymers absorbed at λmax ~317 to 406 nm and emitted at λmax ~370 to 494 nm with fluorescent quantum efficiencies ~24 to 48%. The copolymer with tri‐coordinate boron showed highly efficient fluorescence quenching in the presence of fluoride ions at ratios boron/fluoride ~5/1, demonstrating its potential as anion sensor. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1707–1718 相似文献
39.
Gold(I)/Chiral Brønsted Acid Catalyzed Enantioselective Hydroamination–Hydroarylation of Alkynes: The Effect of a Remote Hydroxyl Group on the Reactivity and Enantioselectivity 下载免费PDF全文
Valmik S. Shinde Manoj V. Mane Dr. Kumar Vanka Arijit Mallick Dr. Nitin T. Patil 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):975-979
The catalytic enantioselective hydroamination–hydroarylation of alkynes under the catalysis of (R3P)AuMe/(S)‐3,3′‐bis(2,4,6‐triisopropylphenyl)‐1,1′‐binaphthyl‐2,2′‐diyl hydrogenphosphate ((S)‐TRIP) is reported. The alkyne was reacted with a range of pyrrole‐based aromatic amines to give pyrrole‐embedded aza‐heterocyclic scaffolds bearing a quaternary carbon center. The presence of a hydroxyl group in the alkyne tether turned out to be very crucial for obtaining products in high yields and enantioselectivities. The mechanism of enantioinduction was established by carefully performing experimental and computational studies. 相似文献