20 research outputs found
Glass forming ability and soft-magnetic properties of Fe-based glassy alloys developed using high phosphorous pig Iron
Glass forming ability (GFA) and soft-magnetic behaviour of melt-spun Fe69C5.5P11.5Mn0.4Si2.3Cr1.8Mo1B8.5
(alloy 2) and Fe68C9P12Mn1Si3Nb2B5, (alloy 3) alloys prepared using high phosphorous pig iron (h-PI,
Fe80C14P2.2Mn0.4Si3.4) has been studied. The glass formation, thermo-physical and soft-magnetic properties
of the alloys were analyzed for different quenching rates by varying wheel speed as 23, 26, 33, 39
and 43 m/s. The simultaneous incorporation of alloying elements (Cr, Mo, Nb) and metalloids (C, B, P, Si)
transforms h-PI to complete glassy alloy, even at low quenching rates. The melt quenching rate influences
the thermal parameters and Curie temperature of glassy ribbons in an opposite way. Amongst
all, FeCPMnSiCrMoB glassy alloy show superior combination of higher glass transition temperature of
788 K, super cooled region of 34 K, glass Curie temperature of 552 K, coercivity less than 13 A/m and
maximum saturation magnetization of 1.1 T. In addition, the annealing treatment at 758 K improves
magnetic softness (1.7 A/m) of the alloy by relaxation of quenched-in stresses. The comparison of
developed glassy alloy with similar Fe-glassy alloys and SENNTIX type alloys show best combination of
thermo-physical and magnetic properties. The glassy alloy prepared using blast furnace high phosphorous
pig iron can be used for uniformly gapped soft-magnetic cores
Taking stock of 10 years of published research on the ASHA programme: Examining India’s national community health worker programme from a health systems perspective
Background: As India’s accredited social health activist (ASHA) community health worker (CHW) programme enters its second decade, we take stock of the research undertaken and whether it examines the health systems interfaces required to sustain the programme at scale.
Methods: We systematically searched three databases for articles on ASHAs published between 2005 and 2016. Articles that met the inclusion criteria underwent analysis using an inductive CHW–health systems interface framework.
Results: A total of 122 academic articles were identified (56 quantitative, 29 mixed methods, 28 qualitative, and 9 commentary or synthesis); 44 articles reported on special interventions and 78 on the routine ASHA program. Findings on special interventions were overwhelmingly positive, with few negative or mixed results. In contrast, 55% of articles on the routine ASHA programme showed mixed findings and 23% negative, with few indicating overall positive findings, reflecting broader system constraints. Over half the articles had a health system perspective, including almost all those on general ASHA work, but only a third of those with a health condition focus. The most extensively researched health systems topics were ASHA performance, training and capacity-building, with very little research done on programme financing and reporting, ASHA grievance redressal or peer communication. Research tended to be descriptive, with fewer influence, explanatory or exploratory articles, and no predictive or emancipatory studies. Indian institutions and authors led and partnered on most of the research, wrote all the critical commentaries, and published more studies with negative results.
Conclusion: Published work on ASHAs highlights a range of small-scale innovations, but also showcases the challenges faced by a programme at massive scale, situated in the broader health system. As the programme continues to evolve, critical comparative research that constructively feeds back into programme reforms is needed, particularly related to governance, intersectoral linkages, ASHA solidarity, and community capacity to provide support and oversight
Investigations on the role of alkali to obtain modulated defect concentrations for Cu2O thin films
An economic successive ionic layer adsorption and reaction (SILAR) method has been investigated for depositing thin Cu2O layers on steel. The mole ratios of the Cu' ions to OH- ions in the alkali bath were varied and the changes in the properties were characterised by X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and Ultraviolet-visible spectroscopy techniques. The increase in the binding energy values of the Cu 2p peaks in XPS established that an optimum copper vacancy concentration can be obtained for a Cu-70H- mole ratio between 1:10 and 1:15; SEM studies confirmed a dense, uniform microstructure for Cu20 thin films coated with these compositions. The strongest absolute peak intensity counts in PL for the peak at 580 nm along with low energy peaks (1.2-1.4 eV) due to Cu vacancy was found to be most prominent for thin film made with Cu-70H- mole ratio 1:15. The role of alkali concentration has been explained in relation to create a stable Cu2_30 structure with optimum copper vacancy. This is an easy way to modulate surface reactivity of the Cu2O thin layers and the concept can be utilised for large area device integrations for various electrical and mechanical applications. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserve