Transition metal clusters containing ferrocenyl diphosphine

ABSTRACT The ligating ability of 1,1-bis(diphenylphosphino)ferrocene (dppf) enables its extensive coordination chemistry to transition metals. To study the various ligating modes of dppf with chalcogenide transition metal clusters, three new compounds were synthesised and their mode of bonding has been studied. [Fe3Te2(CO)9{(PPh2)(C5H4)Fe(C5H4)(PPh2)}] (Te2Red3) was synthesised in room temperature , 31 P NMR spectra shows a singlet denoting dppf adopts a chelating mode of bonding, [Fe3Te2(CO)9{(PPh2)(C5H4)Fe(C5H4)(PPh2)}] (Te2Red1) was synthesised at 0o C and [Fe3Se2(CO)8(į1-dppf)] (Se2Black1) was synthesised at room temperature. From the 31 P NMR spectra it was found that one of the phosphorus was coordinated to the iron metal and the other phosphorus was hanging . The uncoordinated phosphorus was used for further cluster growth reactions with W(CO)5THF and the dppf ligand adopts inter-bridging mode of bonding in the compound [Fe3Se2(CO)8dppfW(CO)5]

Probing Internal Stress and Crystallinity in Wet Foam via Raman Spectroscopy

In this article, we correlate the internal stress and the characteristics of a vibrational mode in wet foam. Using microscope images, we estimate the average size of the bubbles in wet foam, at specific time intervals, over a duration of twenty four hours. Raman spectra are also recorded at the same time intervals, over the same time frame. We show that the internal stress, originated from the macroscopic structural change of foam with ageing, can be related to the observed Raman shift of the low frequency methylene rocking mode of the constituent surfactant molecules in foam. In this report we also show the capability of the Raman spectroscopy to reveal the crystallinity in foamy materials, when studied for a longer period of time.Comment: 16 pages, 7 figure

Inventory model of deteriorating items for nonlinear holding cost with time dependent demand.

The objective of this model is to investigate the inventory system for perishable items where time proportional deterioration rate is considered. The Economic order quantity is determined for minimizing the average total cost per unit time. Time dependent demand rate is used with finite time horizon. Nonlinear holding cost  with shortage is considered. The result is illustrated with numerical example

Evolution of Generalized Brans-Dicke parameter within a Superbounce scenario

We have studied a superbounce scenario in a set up of Brans-Dicke (BD) theory. The BD parameter is considered to be time dependent and is assumed to evolve with the Brans-Dicke scalar field. In the superbounce scenario, the model bounces at an epoch corresponding to a Big Crunch provided the ekpyrotic phase continues until that time. Within the given superbounce scenario, we investigate the evolution of the BD parameter for different equations of state. We chose an axially symmetric metric that has an axial symmetry along the x-axis. The metric is assumed to incorporate an anisotropic expansion effect. The effect of asymmetric expansion and the anisotropic parameter on the evolving and the non-evolving part of the BD parameter is investigated.Comment: 10 pages, 5 figures, accepted version of the journal Symmetr

Assessment of heavy metals in the surrounding soils and their bioconcentrations in few plants near Kathajodi river, Odisha, India

The present study was carried out mainly concentrate on assessment of heavy metal in the surrounding soils and their bioconcentration in the different plants near Kathajodi River. Soil and plant samples were collected along the Kathajodi river, Odisha, India. It was found that the dominance of heavy metals follows a decreasing order. The metal concentrations measured in soil at all location generally decreased in the order; Fe > Mn > Ni> Pb> Cu> Zn> Cd. Highest heavy metal concentration in river bank soil Cd (0.72±0.05 mgkg-1); Ni (3.85±0.15 mgkg-1); Cu (1.66±0.15 mgkg-1); Zn (1.54±0.16 mgkg-1); Pb (4.11±0.14 mgkg-1); Fe (142.0±1.16 mgkg-1); Mn (37.30±1.16 mgkg-1) at different site . Among all the grass species I. laxum has the higher affinity for the accumulation of Cd (0.85±0.05) followed by Zn, Pb and Cu. This study indicates that bio concentration of heavy metals in the study area show preferential Cd uptake in the plants followed by Zn, Pb and it may lead to accumulates in the exposed plant part posing risk along the food chain. This calls for immediate action to be implemented to carry out necessary environment mitigation measures for the river as it can be attributed the discharge of untreated domestic waste and effluents in the river