5,210 research outputs found
Synthesis and properties of nickel-cobalt-boron nanoparticles
morphous cobalt nickel boride nanoparticles were synthesised by chemical reduction synthesis in aqueous solution. Careful control of synthesis conditions and post reaction oxidation enabled the nanoparticles to be converted into a core-shell structure comprising of an amorphous CoâNiâB core and an outer metal oxide sheet. These particles had interesting magnetic properties including saturation magnetisations and coercivities of the order of 80 emu/g and 170 Oe respectively, making them suitable for a potential use as an exchange-pinned magnetic material
Tectonic overview of the West Gondwana margin
The oceanic southern margin of Gondwana, from southern South America through South Africa, West Antarctica, New Zealand (in its pre break-up position), and Victoria Land to Eastern Australia is one of the longest and longest-lived active continental margins known. It was the site of the 18,000 km Terra Australis orogen, which was initiated in Neoproterozoic times with the break-up of Rodinia, and evolved into the Mesozoic Australides. The Gondwana margin was completed, in Late Cambrian times, by closure of the Adamastor Ocean (between Brazilian and southwest African components) and the Mozambique Ocean (between East and West Gondwana), forming the Brasiliano-Pan-African mobile belts. During the Early Palaeozoic much of the southern margin was dominated by successive episodes of subduction-accretion. Eastern Australia, Northern Victoria Land and the Transantarctic Mountains were affected by one of the first of these events â the Late Cambrian Ross/Delamerian orogeny, remnants of which may be found in the Antarctic Peninsula â but also contain two accreted terranes of unknown age and origin. Similar events are recognized at the South American end of the margin, where the Cambrian Pampean orogeny occurred with dextral strike-slip along the western edge of the RĂo de la Plata craton, followed by an Ordovician active margin (Famatinian) associated with the collision of the Precordillera terrane. However, the central part of the margin (the Sierra de la Ventana of eastern Argentina, the Cape Fold Belt of South Africa and the Ellsworth Mountains of West Antarctica) seem to represent a passive margin during the Early Palaeozoic, with the accumulation of predominantly reworked continental sedimentary deposits (Du Toit's âSamfrau Geosynclineâ). In many of the outer areas, accretion and intense granitic/rhyolitic magmatism continued during the Late Palaeozoic, with collision of several small continental terranes, many of which are nevertheless of Gondwana origin: e.g., southern Patagonia and (possibly) âChileniaâ in the South AmericanâSouth African sectors, and the Western Province and Median Batholith terranes of New Zealand. The rhyolitic PermoâTriassic LIP of southern South America represents a Permo-Triassic switch to extensional tectonics, which continued into the Early Jurassic, and was followed by the establishment of the Andean subduction margin. Elsewhere at this time the margin largely became passive, with terrane accretion continuing in New Zealand. In the Mesozoic, the Terra Australis Orogen evolved into the accretionary Australides, with episodic orogenesis in the New Zealand, West Antarctic and South American sectors in Late TriassicâEarly Jurassic and mid-Cretaceous times, even as Gondwana was breaking up
Scaling-up Early Learning in Ethiopia: Exploring the Potential of O-Class
SDG Target 4.2 identifies âpre-primary educationâ as a strategy to strengthen school readiness and contribute to the quality and outcomes of education, which is supported by the powerful evidence from evaluation research. The challenge faced by many countries is to deliver the proven potential of well-planned, quality programmes to scale. This working paper summarises Ethiopiaâs growing commitment to pre-primary education and reports recent Young Lives engagement with the Ministry of Education in Ethiopia and other partners to support scale-up. Ethiopiaâs most recent ambitious targets for early learning have been set out in the Fifth Education Sector Development Programme (ESDP V 2015), with pre-primary classes (known as O-Class) within primary schools being seen as the most rapid route to scale-up.
The paper reports on the progress and the challenges in delivering ambitious targets. We report key findings from exploratory fieldwork on two key themes, namely the response of Regional Education Bureaus in planning, financing, management and ensuring human capacity for scale-up; and the potential of Ethiopiaâs Colleges of Teacher Education to supply sufficient trained teachers to work with young children, especially in the rapidly expanding O- Classes.
The final section draws on parallel experiences of other countries, notably Grade R in South Africa, and reports on six key challenges for scale-up; equity; age-appropriateness; cross- sectoral coordination; capacity building; and research and evidence. Other key challenges go beyond the scope of this working paper, notably the models for governance and financing that can deliver quality early education for all. While Ethiopiaâs initiative to scale-up O-Class is a welcome indicator of policy commitment to SDG Target 4.2, we conclude that there is a risk that low quality pre-primary programmes will not deliver on the potential of early childhood education and that children (especially poor children) will be the losers
The use of coated piezoelectric crystals for the determination of CO and CO[subscript 2]
Imperial Users onl
Religious Culture: Faith in Soviet and Post-Soviet Russia
The former Soviet Union is undergoing a religious revival. People inside and outside the Russian Orthodox church are reexamining its ancient ways, rediscovering its long-forgotten saints, searching its institutional memory for answers to urgent questions facing the nation. The Western reaction to this remarkable resurgence of religion in Russia has been mixed. All observers welcome the fact that free inquiry about religion and free religious worship have been restored in the Russian Federation. At the same time, many are concerned about the xenophobic tendencies that have accompanied the religious revival in Russia and that became especially evident after the liberal forces suffered a defeat in the December 1993 parliamentary election. Calls to restore the great Russian empire sounded by the winners brought to mind the old slogan, Moscow, the Third Rome, that had spurred Muscovy in the 16th-17th centuries to expand its dominion over neighboring countries. The situation is further exacerbated by a few Archbishops and Metropolitans who exhort the Russian people to bring the orthodox, unchanging faith -- Pravoslavie -- to the world
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