2,299 research outputs found

    Superconductivity in 2-2-3 system Y2Ba2Cu2O(8+delta)

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    Researchers synthesized a new high T(sub c) 2-2-3 superconductor Y2Ba2Cu3O(8+delta) by a special preparation technique and characterized it by ac-susceptibility measurements. Diamagnetism and Meissner effect sets in at low fields and superconducting transition onsets at 90 K. The systematic investigation of the real and imaginary components of ac-susceptibility as a function of temperature and applied ac magnetic field reveals that the magnetic behavior is that of a granular type superconductor

    QQˉQ\bar Q (Q{b,c}Q\in \{b, c\}) spectroscopy using Cornell potential

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    The mass spectra and decay properties of heavy quarkonia are computed in nonrelativistic quark-antiquark Cornell potential model. We have employed the numerical solution of Schr\"odinger equation to obtain their mass spectra using only four parameters namely quark mass (mcm_c, mbm_b) and confinement strength (AccˉA_{c\bar c}, AbbˉA_{b\bar b}). The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are computed perturbatively to determine the mass spectra of excited SS, PP, DD and FF states. Digamma, digluon and dilepton decays of these mesons are computed using the model parameters and numerical wave functions. The predicted spectroscopy and decay properties for quarkonia are found to be consistent with available experimental observations and results from other theoretical models. We also compute mass spectra and life time of the BcB_c meson without additional parameters. The computed electromagnetic transition widths of heavy quarkonia and BcB_c mesons are in tune with available experimental data and other theoretical approaches

    Računanje vrpčaste strukture nelokalnim pseudopotencijalima

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    Energy bands of Rb and Cs have been calculated for the first time using average or effective pseudopotentials obtained from non-local ones. It is shown that the results so obtained compare well to those obtained with full non-local calculations.Načinili smo prve račune energijskih vrpci Rb i Cs primjenom prosječnog ili efektivnog pseudopotencijala koji smo izveli iz nelokalnih pseudopotencijala. Pokazuje se dobra suglasnost ishoda tih računa i računa primjenom potpunih nelokalnih pseudopotencijala

    Effective interactions and charges in <SUP>58</SUP>Ni

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    The structure of the low-lying states of 58Ni has been calculated in shell model by assuming an inert 56Ni core plus two valence nucleons in the p3/2, f5/2 and p1/2 orbitals. The two-body matrix elements are first expressed in terms of seven radial matrix elements and these are then parametrized to give best fit between the computed and the observed energies of the levels below 4 MeV. The wave-functions obtained using these two-body matrix elements are used to study the concept of effective charges. It is found that a single effective charge is not sufficient to predict the B(E2) rates equally well for the thirteen known transitions for which experimental values are available. Assumption of state-dependent effective charges gives a far better agreement. An analysis using wave functions obtained with Kuo's two-body matrix elements also gives a similar result

    PDF model based on Langevin equation for polydispersed two-phase flows applied to a bluff-body gas-solid flow,

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    The aim of the paper is to discuss the main characteristics of a complete theoretical and numerical model for turbulent polydispersed two-phase flows, pointing out some specific issues. The theoretical details of the model have already been presented [Minier and Peirano, Physics Reports, Vol. 352/1-3, 2001 ]. Consequently, the present work is mainly focused on complementary aspects, that are often overlooked and that require particular attention. In particular, the following points are analysed : the necessity to add an extra term in the equation for the velocity of the fluid seen in the case of twoway coupling, the theoretical and numerical evaluations of particle averages and the fulfilment of the particle mass-continuity constraint. The theoretical model is developed within the PDF formalism. The important-physical choice of the state vector variables is first discussed and the model is then expressed as a stochastic differential equation (SDE) written in continuous time (Langevin equations) for the velocity of the fluid seen. The interests and limitations of Langevin equations, compared to the single-phase case, are reviewed. From the numerical point of view, the model corresponds to an hybrid Eulerian/Lagrangian approach where the fluid and particle phases are simulated by different methods. Important aspects of the Monte Carlo particle/mesh numerical method are emphasised. Finally, the complete model is validated and its performance is assessed by simulating a bluff-body case with an important recirculation zone and in which two-way coupling is noticeable.Comment: 23 pages, 10 figure

    Relationship between genetic divergence and phenotypic stability in chickpea

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    In this investigation, by and large, genotypes included in the same cluster had identiea means but the linear responses were not the same. However, genotypes included in the same cluster had almost identical non-linear responses. Therefore, grouping of material into different clusters based on regression analysis was found to be reliable as that of Mahalanobis' D2 Statisti

    Superconductivity in 2-2-3 Y2Ba2Cu3O(sub 8+ delta)

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    Researchers synthesized a new high T(sub c) 2-2-3 superconductor (Y2Ba2Cu3O8+delta) by a special preparation technique and characterized it by ac-susceptibility measurements. Diamagnetism and Meissner effect sets in at low fields and superconducting transition onsets at 90 K. The systematic investigation of the real and imaginary components of ac-susceptibility as a function of temperature and applied ac magnetic field reveals that the magnetic behavior is that of a granular type superconductor

    PHARMACOGNOSTICAL AND PHYTO-CHEMICAL EVALUATION OF PIPPALYADI YOGA: A POLYHERBAL FORMULATION

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    Pippalyadi Yoga is Churna Kalpana described by Acharya Chakrapani in Vandhyatva (infertility). Ovulatory dysfunction is the prime cause of Infertility among the world, Pippalyadi Yoga is useful in patients especially having Anovulation which is known as Abeejatva in Ayurveda. So a new pharmaceutical preparation Pippalyadi Yoga in the form of Churna (powder) was tried to standardize which is economical in terms of time and machinery usage. Pharmacognostical and phyto-chemical observations revealed the specific characters of all active constituents used in the preparation. The present work was carried out to standardize the finished product of Pippalyadi Yoga to confirm its identity, quality and purity. The presence of stone cells, oil globules, olio resin cells, parenchymatous cells, oval &amp; beaker shaped starch grains, pollen grains were the characteristic features observed in the microscopy of the prepared drug. Phyto-chemical analysis showed Loss on drying 10.07 % w/w, ash value 6.55 %w/w, water soluble extract 14 % w/w, methanol soluble 13.40 % w/w, particle consistency above 60 mesh 4.10 % w/w, between 60-85 mesh 9.20 % w/w, between 85-120 mesh 13.30 % w/w &amp; below 120 mesh 73.37 % w/w &amp; pH 5.0. HPTLC of Pippalyadi Yoga is the preliminary quantitative analysis which shows 8 prominent spots at Rf. 0.09, 0.61, 0.67, 0.74, 0.80, 0.86, 0.91, 1.00 in UV 254 nm and 7 prominent spots at Rf. 0.06, 0.17, 0.63, 0.67, 0.75, 0.82, 0.88 in UV 366 nm. Pippalyadi Yoga, a polyherbal formulation of 4 ingredients was prepared and HPTLC finger print profile was developed and it can be considered pharmacopial standard of Pippalyadi Yoga
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