11,073 research outputs found
An effective Nuclear Model: from Nuclear Matter to Finite Nuclei
The momentum and density dependence of mean fields in symmetric and
asymmetric nuclear matter are analysed using the simple density dependent
finite range effective interaction containing a single Gaussian term alongwith
the zero-range terms. Within the formalism developed, it is possible to
reproduce the various diverging predictions on the momentum and density
dependence of isovector part of the mean field in asymmetric matter. The finite
nucleus calculation is formulated for the simple Gaussian interaction in the
framework of quasilocal density functional theory. The prediction of energies
and charge radii of the interaction for the spherical nuclei compares well with
the results of other effective theories.Comment: 10 pages, 3 figures, 2 tables, To appear in the Proceedings of the
11th International Conference on Nucleus-Nucleus Collisions (NN2012), May
27-June 1, 2012, San Antonio, Texas, US
Synthesis of thiazole, benzothiazole, oxadiazole, thiadiazole, triazole and thiazolidinone incorporated coumarins
3-Bromoacetylcoumarin-(2)obtained by brominationof 3-acetylcoumarin (1)was condensed with2-amin0-4-phenylthiazole,2-aminothiazole,2-aminobenzothiazole, 2-
amino-4-phenyloxadiazole, 2-aminothiadiazole, 3-aminotriazole to form the corresponding heteroaryl aminoacetylcoumarins (3a-f).The reaction of 2 withthiourea
furnished 2-amino-4-(coumarinyl-3) thiazole (4) which further reacted with phenyli$othiocyanate forming the unsymmetrical thiourea (5). The thiourea on cyclocondensation withchloroacetic acid gave the thiazolidinone (6)which on further reaction with differen~aromaUcaldehydes resulted inthe formationofthe corresponding arylidene compounds (7). The structures of the products were confirmed from their analytical and spectraldata
Mineralogical characterization and sorption properties of goethite rich iron ore from daitari, Orissa, India
The present study was an attempt to find alternative uses of goethite rich iron ore, usually not used as raw material for iron extraction, as an adsorbent for removal of anionic contaminants from water. Mineralogical characterization by optical microscope, XRD revealed the presence of substantial amount goethite in the iron ore which was also supported from the TG-DTA and FT-IR results. On heating in air, the goethite content was completely converted to hematite at 400°C. The sorption behaviour of the untreated (GRI-0) and heat treated iron ore were studied using aqueous phosphate solution as the adsorbate with respect to effect of pH, initial phosphate concentration, amount of adsorbent, interfering anions and heat treatment. Phosphate uptake was seen to increase with increasing temperature of heat treatment, attains a maximum value at 300°C and thereafter decreased on further increase of temperature. The experimental equilibrium adsorption data were fitted well to Langmuir isotherm model. The complete desorption of adsorbed phosphate at pH ≥ 12.0 indicated the adsorption of phosphate was reversible and may be reused further. The results obtained could be useful for considering GRI-0 as adsorbent for removal of phosphate ions from contaminated water bodies
Carrier Selectivity and Passivation at the Group V elemental 2D Material--Si Interface of a PV Device
This study investigates the interfacial characteristics relevant to
photovoltaic (PV) devices of the Group--V elemental 2D layers with Si. The
surface passivation and carrier selectivity of the interface between
and allotropes of arsenene, antimonene, and bismuthene monolayers with
Si (100) and Si(111) were estimated \emph{via} first--principles calculations.
Amongst the various interface configurations studied, all of the Si(111)--based
slabs and only a couple of the Si(100)--based slabs are found to be stable.
Bader charge analysis reveals that charge transfer from/to the Si slab to
(As)/from (Sb and Bi) in the 2D layer occurs, indicating a strong interaction
between atoms across the interface. Comparing within the various configurations
of a particular charge (electron or hole) selective layer, the structural
distortion of the Si slab is the lowest for --As/Si and -Bi/Si.
This translates as a lower surface density of states (DOS) in the band gap
arising out of the Si slab when integrated with --arsenene and
--bismuthene, implying better surface passivation. All-in-all, our
analysis suggests -As as the best candidate for a passivating electron
selective layer, while -Bi can be a promising candidate for a
passivating hole selective layer
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