Short range correlations in relativistic nuclear matter models

Short range correlations are introduced using unitary correlation method in a relativistic approach to the equation of state of the infinite nuclear matter in the framework of the Hartree-Fock approximation. It is shown that the correlations give rise to an extra node in the ground-state wave-function in the nucleons, contrary to what happens in non-relativistic calculations with a hard core. The effect of the correlations in the ground state properties of the nuclear matter and neutron matter is studied. The nucleon effective mass and equation of state (EOS) are very sensitive to short range correlations. In particular, if the pion contact term is neglected a softening of the EOS is predicted. Correlations have also an important effect on the neutron matter EOS which presents no binding but only a very shallow minimum contrary to the Walecka model.Comment: 8pages, 4 figure

Alkali Metal & Alkaline-Earth Metal Complexes of Various Amidophosphines having P, N, Chalcogen and Borane as Donor atoms/group – Syntheses, Structures and Ring-Opening Polymerization of Caprolactone

During the last decade, heavy alkaline-earth organometallic chemistry has emerged from obscurity to becoming a vibrant area of research, owing to a number of synthetic pathways that provide reliable access to these highly reactive target compounds. The complexes of heavy alkaline-earth metals were employed in various catalytic applications such as ring-opening polymerization of various cyclic esters, polymerization of styrene and dienes, and hydroamination and hydrophosphination reactions of alkenes and alkynes. Particularly, Group 2 metal complexes have been received considerable attention as initiators for the ROP of cyclic esters and some of them have demonstrated impressive results. Aliphatic polyesters are currently considered as alternatives to synthetic petrochemical-based polymers. Their biodegradable and biocompatible nature along with their mechanical and physical properties make them prospective thermoplastics with broad commercial applications such as single-use packaging materials, medical sutures and drug delivery systems. Ring-opening polymerization (ROP) of cyclic esters promoted by alkaline-earth & rare-earth metal initiators proved to be the most efficient way for preparing polyesters with controlled molecular weight and microstructure and narrow molecular-weight distribution. Therefore, the design and synthesis of new well-defined single-site catalysts that exhibits good activity, productivity and selectivity for cyclic ester polymerization is needed

Structural Carbohydrates and Lignifications Associated with Submergence Tolerance in Rice (Oryza sativa L.)

Role of structural carbohydrate content and lignifications in rice shoot were studied in three indica rice (Oryza sativa L.) cultivars namely FR13A (tolerant to submergence), IR42 (susceptible to submergence) and Sabita (adapted to medium depth, 0-50 cm stagnant flooding), varying degrees of tolerance to submergence under control and 8 days after submergence conditions. During submergence, Sabita and IR 42 accelerated the rate of stem and leaf elongation more than that of FR 13A. Submergence significantly reduces the cellulose and hemicelluloses content. The decrease was more pronounced in susceptible rice cultivar than that of tolerant rice cultivar. Lignifications’ was monitored by measuring the content of lignin and the activities of two enzymes of the lignin biosynthetic pathway, coniferyl alcohol dehydrogenase (CAD) and phenylalanine ammonia-lyase (PAL) in rice shoots. Lignin content and PAL and CAD activity was more in susceptible cv. both under control and 8d after submergence. In conclusion submergence induced elongation of rice shoot might decreased the structural carbohydrate level as our experiment showed a significant negative correlation of cellulose and hemicelluloses with plant height but also positively associated with plant survival under submergence. The content of lignin and activities of CAD and PAL showed negative association with shoot elongation, yet the association of these parameters with survival was non-significant

Gluconate Complexes of Cu(II) & Zn(II)

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