Studies on radiation pasteurisation of medium fatty fish 1. Control of radiation induced oxidative changes in white pomfret (Stromateus cinereus) by vacuum packaging

Marked differences were observed in proximate biochemical compositions of the skin and muscle of white pomfret. The skin showed comparatively higher content of extractable lipids and was more susceptible to radiation-induced oxidative changes like development of rancid odours and yellow discolouration than the muscle. Irradiation of skin samples under vacuum suppressed these changes. The present paper also reports on the efficacy of vacuum packaging in controlling oxidative rancidity and yellow discolouration in white pomfret skin subjected to irradiation and subsequent storage at 0-2°C

Studies on radiation pasteurisation of medium fatty fish 3. Storage properties of white pomfret (Stromateus cinereus) fillets

White pomfret fillets packed under aerobic conditions had a limited shelf life of 8 days as against 10 days for samples packed under vacuum and stored at 0-2°C. Irradiation and subsequent storage of the fillets under vacuum at 0-2°C exhibited shelf lives of 30, 50 and 60 days for radiation doses of 0.1, 0.3 and 0.5 Mrad respectively in contrast to aerobically packed fillets which showed only 20, 35 and 50 days of storage life for the same levels of radiation doses and developed yellow discolouration and rancid odours

Image forces on screw dislocations in multilayer structures

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26533/1/0000072.pd

Investigating the Temperature Effects on ZnO, TiO2, WO3 and HfO2 Based Resistive Random Access Memory (RRAM) Devices

In this paper, we report the effect of filament radius and filament resistivity on the ZnO, TiO2, WO3 and HfO2 based Resistive Random Access Memory (RRAM) devices. We resort to the thermal reaction model of RRAM for the present analysis. The results substantiate decrease in saturated temperature with increase in the radius and resistivity of filament for the investigated RRAM devices. Moreover, a sudden change in the saturated temperature at a lower value of filament radius and resistivity is observed as against the steady change at the medium and higher value of the filament radius and resistivity. Results confirm the dependence of saturated temperature on the filament size and resistivity in RRAM

Atomistic Studies of Defect Nucleation during Nanoindentation of Au (001)

Atomistic studies are carried out to investigate the formation and evolution of defects during nanoindentation of a gold crystal. The results in this theoretical study complement the experimental investigations [J. D. Kiely and J. E. Houston, Phys. Rev. B, v57, 12588 (1998)] extremely well. The defects are produced by a three step mechanism involving nucleation, glide and reaction of Shockley partials on the {111} slip planes noncoplanar with the indented surface. We have observed that slip is in the directions along which the resolved shear stress has reached the critical value of approximately 2 GPa. The first yield occurs when the shear stresses reach this critical value on all the {111} planes involved in the formation of the defect. The phenomenon of strain hardening is observed due to the sessile stair-rods produced by the zipping of the partials. The dislocation locks produced during the second yield give rise to permanent deformation after retraction.Comment: 11 pages, 13 figures, submitted to Physical Review

Investigating the Temperature Effects on ZnO, TiO2, WO3 and HfO2 Based Resistive Random Access Memory (RRAM) Devices

In this paper, we report the effect of filament radius and filament resistivity on the ZnO, TiO2, WO3 and HfO2 based Resistive Random Access Memory (RRAM) devices. We resort to the thermal reaction model of RRAM for the present analysis. The results substantiate decrease in saturated temperature with increase in the radius and resistivity of filament for the investigated RRAM devices. Moreover, a sudden change in the saturated temperature at a lower value of filament radius and resistivity is observed as against the steady change at the medium and higher value of the filament radius and resistivity. Results confirm the dependence of saturated temperature on the filament size and resistivity in RRAM

Optimization of the Strength-Fracture Toughness Relation in Particulate-Reinforced Aluminum Composites via Control of the Matrix Microstructure

The article of record as published may be found at http://dx.doi.org/10.1007/s11661-998-0119-9The evolution of the microstructure and mechanical properties of a 17.5 vol. pct SiC particulatereinforced aluminum alloy 6092-matrix composite has been studied as a function of postfabrication processing and heat treatment. It is demonstrated that, by the control of particulate distribution, matrix grain, and substructure and of the matrix precipitate state, the strength-toughness combination in the composite can be optimized over a wide range of properties, without resorting to unstable, underaged (UA) matrix microstructures, which are usually deemed necessary to produce a higher fracture toughness than that displayed in the peak-aged condition. Further, it is demonstrated that, following an appropriate combination of thermomechanical processing and unconventional heat treatment, the composite may possess better stiffness, strength, and fracture toughness than a similar unreinforced alloy. In the high- and low-strength matrix microstructural conditions, the matrix grain and substructure were found to play a substantial role in determining fracture properties. However, in the intermediate- strength regime, properties appeared to be optimizable by the utilization of heat treatments only. These observations are rationalized on the basis of current understanding of the grain size dependence of fracture toughness and the detailed microstructural features resulting from thermomechanical treatments.United States Army Research OfficeArmy Research LabratoryUnited States Air Force Office of Scientific ResearchWright Materials LabratoryDWA Composite

Surface termination dependent structural and magnetic properties of (0001) SmCo5 slabs

We employ first principles calculations to understand the surface termination dependent structural and magnetic properties of (0001) SmCo5 surface slabs. For our study, three different sub-layer terminated surface slabs, namely Co3– (SmCo2–Co3)n, SmCo2–(Co3–SmCo2)n, and (Co3–SmCo2)n with thicknesses varying from n ¼ 1 to n ¼ 10, are considered. Our results revealed that the Co3 sub-layer terminated surface slab (first case) has higher structural stability, spin polarization, and work function when compared to the other two cases and such terminated surface slabs can be potentially used for fabricating exchange-coupled magnet