8,858 research outputs found
Development and application of rice starch based edible coating to improve the postharvest storage potential and quality of plum fruit (<i>Prunus salicina</i>)
The study investigated the possibility of enhancing the shelf life of plum fruit coated with rice starch-ι-carrageenan (RS-ι-car) composite coating blended with sucrose fatty acid esters (FAEs). Film solution (starch 3%, carrageenan 1.5% and FAEs 2%) was prepared by mixing the ingredients and properties of stand-alone films (physical, mechanical, barrier and surface morphology) were studied before applying the coating on fruit surface. Fruit were stored at 20 °C for 3 weeks and analyzed for weight loss, ethylene production, respiration rate, color change, firmness, and titratable acidity (TA) and soluble solid content (SSC). Surface morphology of stand-alone film and fruit surface (after applying on the plum fruit) was studied using scanning electron microscopy (SEM). Phytochemical analysis was performed during the storage period and total phenolic content (TPC), total antioxidant capacity (TAC), flavonoid content (FC) and free radical scavenging activity were determined. The rice starch composite coating was shown to be effective in reducing both weight loss (WL) and respiration rate and inhibiting the endogenous ethylene production when compared to the uncoated control fruit stored at room temperature (p < 0.05). TPC, TAC, FC and free radical scavenging activity was unaffected in the coated fruit throughout the storage period (p < 0.05). The findings reported in this study indicate that the RS-ι-car-FAEs coating prolongs the shelf life and maintains the overall quality of plum fruit during storage and could potentially be commercialized as a new edible coating for the plum fruit industry
Bumper catch of Pampus chinensis (Euphrasen, 1788) landed at New Ferry Wharf, Mumbai
Pomfrets are considered a valuable seafood
delicacy and enjoy great market demand in
Maharashtra. An unprecedented high catch (Plate 1)
of Pampus chinensis commonly known as ‘Chinese
pomfret was landed by trawlers at New Ferry Wharf
on 20-10-07. The fishing ground was towards northwest
at a depth of 30-40 m
Exchange bias in GeMn nanocolumns: the role of surface oxidation
We report on the exchange biasing of self-assembled ferromagnetic GeMn
nanocolumns by GeMn-oxide caps. The x-ray absorption spectroscopy analysis of
this surface oxide shows a multiplet fine structure that is typical of the Mn2+
valence state in MnO. A magnetization hysteresis shift |HE|~100 Oe and a
coercivity enhancement of about 70 Oe have been obtained upon cooling (300-5 K)
in a magnetic field as low as 0.25 T. This exchange bias is attributed to the
interface coupling between the ferromagnetic nanocolumns and the
antiferromagnetic MnO-like caps. The effect enhancement is achieved by
depositing a MnO layer on the GeMn nanocolumns.Comment: 7 pages, 5 figure
On the optical properties of Ag^{+15} ion-beam irradiated TiO_{2} and SnO_{2} thin films
The effects of 200-MeV Ag^{+15} ion irradiation on the optical properties of
TiO_{2} and SnO_{2} thin films prepared by using the RF magnetron sputtering
technique were investigated. These films were characterized by using UV-vis
spectroscopy, and with increasing irradiation fluence, the transmittance for
the TiO_{2} films was observed to increase systematically while that for
SnO_{2} was observed to decrease. Absorption spectra of the irradiated samples
showed minor changes in the indirect bandgap from 3.44 to 3.59 eV with
increasing irradiation fluence for TiO_{2} while significant changes in the
direct bandgap from 3.92 to 3.6 eV were observed for SnO_{2}. The observed
modifications in the optical properties of both the TiO_{2} and the SnO_{2}
systems with irradiation can be attributed to controlled structural
disorder/defects in the system.Comment: 6 pages, ICAMD-201
Evolution of magnetic phases and orbital occupation in (SrMnO3)n/(LaMnO3)2n superlattices
The magnetic and electronic modifications induced at the interfaces in
(SrMnO)/(LaMnO) superlattices have been investigated
by linear and circular magnetic dichroism in the Mn L x-ray absorption
spectra. Together with theoretical calculations, our data demonstrate that the
charge redistribution across interfaces favors in-plane ferromagnetic (FM)
order and orbital occupation, in agreement with the
average strain. Far from interfaces, inside LaMnO, electron localization
and local strain favor antiferromagnetism (AFM) and
orbital occupation. For the high density of interfacial planes ultimately
leads to dominant FM order forcing the residual AFM phase to be in-plane too,
while for the FM layers are separated by AFM regions having
out-of-plane spin orientation.Comment: accepted for publication as a Rapid Communication in Physical Review
A method for measuring the Neel relaxation time in a frozen ferrofluid
We report a novel method of determining the average Neel relaxation time and
its temperature dependence by calculating derivatives of the measured time
dependence of temperature for a frozen ferrofluid exposed to an alternating
magnetic field. The ferrofluid, composed of dextran-coated Fe3O4 nanoparticles
(diameter 13.7 nm +/- 4.7 nm), was synthesized via wet chemical precipitation
and characterized by x-ray diffraction and transmission electron microscopy. An
alternating magnetic field of constant amplitude (H0 = 20 kA/m) driven at
frequencies of 171 kHz, 232 kHz and 343 kHz was used to determine the
temperature dependent magnetic energy absorption rate in the temperature range
from 160 K to 210 K. We found that the specific absorption rate of the
ferrofluid decreased monotonically with temperature over this range at the
given frequencies. From these measured data, we determined the temperature
dependence of the Neel relaxation time and estimate a room-temperature
magnetocrystalline anisotropy constant of 40 kJ/m3, in agreement with
previously published results
- …