477 search results
Cold Pressing and Sintering of Powders
Science, Maths & Technology

Cold Pressing and Sintering of Powders

...compositions are cold compacted and sintered. The main additions to iron powder (usually a sponge-type powder) include the following elements: graphite (carbon), 0.3–1.0 wt%; copper (infiltration), 1.5–11.0 wt%; nickel, 1.0–8.0 wt% Typical sintered properties of steels are as follows: Tensile strength (MPa) Yield strength (MPa) Elongation (%) Fe-0.5C (density 6.8 g...
View article Cold Pressing and Sintering of Powders
Article 5 mins
Electrochemical Machining (ECM)
Science, Maths & Technology

Electrochemical Machining (ECM)

...composition and pressure, spark resistance, cost, etc. Most common electrolytes are sodium chloride (60–240 g l – 1) and sodium nitrate (120–480 g l –1), which requires special safety precautions. Electrolyte flow rate is approximately 1 l min- 1 (100 A) –1 with a velocity of 1500–3000 m min- 1 and a temperature of 25–45°C. Inlet pressures are 137–2060 k...
View article Electrochemical Machining (ECM)
Article 5 mins
Writing from the heart
Education & Development

Writing from the heart

...compositions. Their comments reflected the personal dimension of writing, its connection to the writer, to voice and ownership. The teachers were frequently invited to look back and remember; to lean on their lives as a rich resource and they recalled and re-voiced tales and incidents related to (for example) family practices around names and naming, their memories of...
View article Writing from the heart
Article 10 mins
Strange coloured teeth; strange coloured bones
Science, Maths & Technology

Strange coloured teeth; strange coloured bones

...composition of the bones was altered over the thousands of years they spent in the cave. Specifically, the colour change appears to have been brought about by heating following the incorporation of the metal manganese (oxidizing it to the Mn5+ valence state, which forms blue-coloured salts). This mechanism also appears to explain the origins of turquoise-like ivory...
View article Strange coloured teeth; strange coloured bones
Article 5 mins
Why Cilla Black was more than just a light entertainment star
History & The Arts

Why Cilla Black was more than just a light entertainment star

...sang on stage with some, was dubbed “Swinging Cilla”, and John Lennon persuaded Beatles manages Brian Epstein to give her an audition. One was unsuccessful, but a second led to him offering her a contract. Her first (minor) hit was a cover of a Lennon-McCartney song (Love of the Loved), framed by a rather try-hard press release dubbing her the “bird in a...
View article Why Cilla Black was more than just a light entertainment star
Article 5 mins
Toyota diffusion (TD)
Science, Maths & Technology

Toyota diffusion (TD)

...composition of the base material. Process times range from 30 min up to 10 h to obtain optimum thicknesses in the range 5–15 µm. No expensive vacuum chambers are required such as those used for PVD processes, and no gas-tight reaction vessels are required such as those used for CVD processes. No unpleasant by-product gases, as produced by CVD processes. Materials: TD...
View article Toyota diffusion (TD)
Article 10 mins
Climate change's causes, effects and geographies of responsibility
Society, Politics & Law

Climate change's causes, effects and geographies of responsibility

...composition of the river water around the village was more saline. [Dhaka Bangladesh] Dhaka, Bangladesh There was one question that we asked all of our interviewees: what did they know of climate change, its causes and effects? We asked this of the professionals we interviewed in Dhaka, as well as the villagers of Paikgacha. Almost all our interviewees said that climate...
View article Climate change's causes, effects and geographies of responsibility
Article 10 mins
Practising science: Reading the rocks and ecology
Science, Maths & Technology

Practising science: Reading the rocks and ecology

...composition recognise the difference between a body fossil and a trace fossil...Practising science: reading the rocks and ecology: 1 Earth Sciences: reading the rocks - The Earth Sciences concern every part of our planet – from the centre of the metallic core, 6400 km below our feet, through its solid and liquid regions (see Figure 1 on the next page) to the outer...
View course Practising science: Reading the rocks and ecology
Level 1: Introductory 14 hrs