Material thinking

Learning takes time and effort. Daily skim the text and other study material, think about it, visualize key points and concepts, write down important information, make outlines, take notes, study sample problems, etc. All of these help, but some may help you more than others, so focus on these modes of learning, but not at the exclusion of the other aspects. 

More, because k has units of 1/length and e is dimensionless, the coefficient of k2 must have units of length squared. What length to associate with this coefficient The only length available is some characteristic spacing in the material. Think, for example, of an interatomic spacing a ... 

You ll need to keep track of the material you re citing. If you are taking notes on published text, make it clear that you are copying someone else s work. Note the source, put it in quotes, make the font purple—do whatever it takes to make sure that six months from now, you don t go back to this material, think that you ve written it yourself, and incorporate it into narration, only to find out that you ve lifted entire sentences from someone else. This is also true of material you cut and paste from the web. It is never permissible to use it without attribution. 

Carter, P. (2004) Material Thinking The Theory and Practice of Creative Research, Melbourne Melbourne University Press. 

Vacuum forming is a variation of a classic forming technique, where a sheet of material is heated slightly (not melted) to make it pliable, and then placed over a mold. In the classic technique, the material simply drapes over the mold, as a result of gravity and the mechanics of the material. (Think of a piece of leather, and a wooden shoe mold.) In vacuum... 

The field of fullerene chemistry expanded in an unexpected direction in 1991 when Sumio lijima of the NEC Fundamental Research Laboratories in Japan discovered fibrous carbon clusters in one of his fullerene preparations This led within a short time to substances of the type portrayed in Figure 11 7 called single-walled nanotubes The best way to think about this material IS as a stretched fullerene Take a molecule of Ceo cut it in half and place a cylindrical tube of fused six membered carbon rings between the two halves... 

Since the diffusion coefficient is constant for a given material, Eq. (2.63) shows that the time required for a displacement increases with the square of the distance traveled. This can be understood by thinking that the displacement criterion would be met by finding the diffused particle anywhere on the surface of a sphere of radius x after time t if it started at the origin. The surface area of a sphere is proportional to the square of its radius. 

A new edition of any book presents an opportunity which an author welcomes for several reasons. It is a chance to respond to constructive criticisms of the previous edition which he thinks are valid. New material can be introduced which may be useful to teachers and students in the light of the way the subject, and the teaching of the subject, has developed in the intervening years. Last, and certainly not least, there is an opportunity to correct any errors which had escaped the author s notice. 

This is a standard friction problem. A glance at Fig. 25.5 shows that, when polymers slide on metals and ceramics, x can be as low as 0.04. Among the polymers with the lowest coefficients are PTFE (Teflon ) and polyethylene. By coating the ski or sledge runners with these materials, the coefficient of friction stays low, even when the temperature is so low that frictional heating is unable to produce a boundary layer of water. Aircraft and sports skis now have polyethylene or Teflon undersurfaces the Olympic Committee has banned their use on bob-sleds, which already, some think, go fast enough. 

One thinks of aluminium as a cheap material - aluminium spoons are so cheap that they are thrown away. It was not always so. Napoleon had a set of cutlery specially made from the then-new material. It cost him more than a set of solid silver. 

The way to think of them all is as Si04 tetrahedra (or, in polymer terms, monomers) linked to each other either directly or via a metal ion (M) link. When silica is combined with metal oxides like MgO, CaO or AI2O3 such that the ratio MO/SiOj is 2/1 or greater, then the resulting silicate is made up of separated Si04 monomers (Fig. 16.4a) linked by the MO molecules. (Olivene, the dominant material in the Earth s upper mantle, is a silicate of this type.)... 

In addition to being useful for side studies, the process specification sheets can be used as a file to capture the latest thinking for each individual unit of major material for cost estimation and final design. Vendor quotes are expedited if data is provided to them on standard-type process specification sheets. 

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