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991.
Amrita Mukherjee S.S. Bhattacharyya M. Marik B.K. Chaudhuri K.C. Majumdar 《Phase Transitions》2013,86(11-12):908-915
Detailed dielectric relaxation behavior of a bent core liquid crystalline material showing B2 phase has been investigated. Only one relaxation mode is detected in the dielectric relaxation spectrum which was attributed to the long-axis rotation process. Though the field-dependent dielectric study does not reveal any other relaxation mode, the appearance of two humps in the dielectric permittivity–voltage spectrum, similar to the antiferroelectric (AFLC) case, confirms the signature of weak AFLC ordering in the B2 phase. 相似文献
992.
On the structure and chemistry of complex oxide nanofeatures in nanostructured ferritic alloy U14YWT
D. Bhattacharyya P. Dickerson G.R. Odette S.A. Maloy A. Misra M.A. Nastasi 《哲学杂志》2013,93(16):2089-2107
The remarkable radiation damage resistance of nanostructured ferritic alloys (NFAs) is attributed to the large numbers of matrix nanofeatures (NFs) of various types, which can enhance the recombination of displacement defects and trap transmutant helium in fine scale bubbles. Characterizing the chemistry, crystallographic structure and orientation relationships of the NFs is critical to understanding how they enhance the radiation damage resistance of NFAs. Conventional and high-resolution transmission electron microscopy and energy-dispersive spectroscopy were used to characterize the various types of NF and larger oxide phases in a model 14Cr–3?W–0.4Ti–0.25Y2O3 NFA (14YWT) hot isostatic pressed (HIP-ed) at 1150°C. Large CrTiO3 precipitates (50–300?nm) and small diffracting NFs (<5?nm) were found in this alloy. One major new result is the observation of an additional type of nanofeature (10–50?nm), orthorhombic in structure, with a square center cross-section, which constitutes a new kind of Y–Ti-oxide phase with lattice parameters different from those of known Y and Ti complex oxides. The interfaces of these particles seem to be semicoherent, while manifesting a possible orientation relationship with the BCC matrix. The ratio of Y to Ti varies between <1 and 2 for these larger NFs. 相似文献
993.
994.
The reactions of [Ru(H)(Cl)(CO)(PPh3)3] with 3,5-di-tert-butyl-o-benzoquinone (dbq) and 3,4,5,6-tetrachloro-o-benzoquinone (tcq) have afforded the corresponding semiquinone complexes [RuII(dbsq)(Cl)(CO)(PPh3)2] and [RuII(tcsq)(Cl)(CO)(PPh3)2], respectively. The reaction of [Ru(H)2(CO)(PPh3)3] with tcq has furnished [RuII(tcsq)(H)(CO)(PPh3)2]. Structure determination of [Ru(dbsq)(Cl)(CO)(PPh3)2] has revealed that it is a model semiquinonoid chelate with two equal C---O lengths ( 1.291(6) and 1.296(6) Å). The complexes are one-electron paramagnetic (1.85μB) and their EPR spectra in fluid media display a triplet structure (g2.00) due to superhyperfine coupling with two trans-31P atoms (Aiso17 G). The stretching frequency of the CO ligand increases by 20 cm−1 in going from [Ru(dbsq)(Cl)(CO)(PPh3)2] to [Ru(tcsq)(Cl)(CO)(PPh3)2] consistent with electron withdrawal by chloro substituents. For the same reason the E1/2 values of the cyclic voltammetric quinone/semiquinone and semiquinone/catechol couples undergo a shift of 500 mV to higher potentials between [Ru(dbsq)(Cl)(CO)(PPh3)2] and [Ru(tcsq)(Cl)(CO)(PPh3)2]. 相似文献
995.
In the present paper, a mathematical model, originally proposed by Danziger and Elmergreen and describing the thyroid-pituitary
homeostatic mechanism, is modified and analyzed for its physiological and clinical significance. The inuence of different
system parameters on the stability behavior of the system is discussed. The transportation delays of different hormones in
the bloodstream, both in the discrete and distributed forms, are considered. Delayed models are analyzed regarding the stability
and bifurcation behavior. Clinical treatment of periodic catatonic schizophrenia is discussed in presence of transportation
delays. Numerical simulations are presented to support analytic results. 相似文献
996.
We attempt in this paper to deal with some aspects of the direct photon production phenomenon mainly in the Pb+Pb and Au+Au collisions on the basis of a model for production of the same particle species in PP collisions. The results have, thereafter, been converted to those for a few AB/AA interactions through an appropriate mechanism. Comparison of the theoretical results obtained on the basis of model-based calculations with measured data on the relevant observables leads to a fair agreement between them. This reflects modestly the fair achievements attained by the models that are made use of in the present work. 相似文献
997.
An emission band system in the region 5700–6700 Å from Dergaon stoney iron meteorite which fell at Dergaon, India on March 2, 16.40 local time (2001) was excited with the help of a continuous 500 mW Ar+ laser. The band system is attributed to silicate (olivine), a major component of the meteorite. 相似文献
998.
A mathematical model describing a single species fishery is presented. The coupling effect of intra-species interaction delay of the harvested species and the spatial non-homogeneity of the aquatic environment is studied. The analysis is performed in a finite domain with the help of Neumann boundary value problem which resembles a closed-habitat fishery. Existence, uniqueness and regularity of solutions are demonstrated using the method of upper-lower solution pair. Stability criteria of the system is derived and interpreted from a bio-economic viewpoint. 相似文献
999.
Gautam Bhattacharyya 《Pramana》2007,69(5):903-907
We consider the UED scenario and study the detectability of the first KK electron-positron pair at the ILC. A few hundred
GeV KK electron decays into a nearly degenerate KK photon, which carries away missing energy, and the standard electron. The
mass splitting between the KK electron and KK photon is controlled by the bulk-and brane-induced radiative corrections. We
look for the signal event e
+
e
− + large missing energy for √s = 1 TeV and observe that with a few hundred fb−1 luminosity the signal can be deciphered from the standard model background. We briefly outline how the UED signals may be
distinguished from the supersymmetric signals.
This talk is based on a work the author did with Paramita Dey, Anirban Kundu and Amitava Raychaudhuri [1]. 相似文献
1000.
P. Guptaroy Bhaskar De S. Bhattacharyya D. P. Bhattacharyya 《Acta Physica Hungarica A》2002,15(1-2):103-116
The present work pertains to the production of some very important negatively charged secondaries in lead-lead and gold-gold collision at AGS, SPS and RHIC energies. We would like to examine here the role of the particular version of Sequential Chain Model (SCM), which was applied widely in the past in analysing data on various high-energy hadronic collisions, in explaining now the latest findings on the features of particle production in the relativistic nucleus-nucleus collisions. The agreement between the model of our choice and the measured data is found to be modestly satisfactory in cases of the most prominent and abundantly produced varieties of the secondaries in the above-stated two nuclear collisions. 相似文献