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    Time to achieve specific heat transfer for fluid flowing in a pipe

    http://en.wikipedia.org/wiki/Heat_transfer_coefficient#Heat_transfer_coefficient_of_pipe_wall http://en.wikipedia.org/wiki/Convective_heat_transfer#Newton.27s_law_of_cooling
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    Internal stress in the Al extrusion

    work hardening I would think. Prefer the least amount of stress...I think it would be an aluminium that has undergone significant Ostwald ripening.
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    One-Way Piezoelectric Material

    I imagine if you had the piezoelectric material mounted on a substrate. And it was segregated. then when you bent it to be convex, the piezo electric elements would have gaps in between it and thus be under significantly less stress.
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    Ultra high stretch cycle elastics?

    To add, You will have to analyse the force the spring will be under, then convert it to a force/area to get the tension. This can be compared to the fatigue limit of spring steel to see if its under. If it isn't then one will have to choose a spring with a larger diameter wire.
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    Ultra high stretch cycle elastics?

    The process of failure is fatigue. In turn fatigue also has a temperature dependent process called creep. You'd have to select a material that can withstand the cycles at the specified max temperature. Having said that, many steels possess a fatigue limit, which is loosely defined as a cyclic...
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    How much weight can .75 sq tube tripod handle

    This is more a mechanical engineering problem than materials. quite a range of materials would do, but practically speaking that's not what you want to know about. I suggest you do a bit of reading on truss's to get an idea of the forces involved https://en.wikipedia.org/wiki/Truss...
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    Semi-compressible encapsulated gas suspension as a working fluid

    Thanks. I understand the connotations of the site, but I am not that way inclined. I tend to have more follow through than a typical 'baker'. This idea, if feasible, would be a potential research project at my university.
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    Ultra high stretch cycle elastics?

    Could a spring be more appropriate?
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    Semi-compressible encapsulated gas suspension as a working fluid

    Been playing with this idea http://www.halfbakery.com/idea/Quasi-aerogel It's been boiled down to some sort of elastomeric beads, filled with a suitable gas/fluid/liquid (depending on pressure/temperature) suspended in a liquid. The idea is to increase pumping and compression...
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    Using magnetism to control the structure of concrete

    So this is my idea: make concrete using iron sand, preferably one with a decent ferromagnetic interaction. As the concrete sets, apply a magnetic field. The ferromagnetic particles align to the field creating a structure within the concrete. Possible to coat the iron sand in a retarding...
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    Calculating electric field produced by micro crystalline piezoelectric grains

    what about a piezomagnetic material? it would produce a changing magnetic field under shock which would induce an electric field
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    Calculating electric field produced by micro crystalline piezoelectric grains

    By not want are you saying it would be electrified? wouldn't the random orientation of the piezo crystals negate each other? so you would only get localized currents.
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    Calculating electric field produced by micro crystalline piezoelectric grains

    In the case of a conducting material, would the space charge be conducted? I am unclear what I'm trying to say, would it redistribute the electron cloud?...curses I think what i mean is will an electron wind be generated?
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    Calculating electric field produced by micro crystalline piezoelectric grains

    if its that small, how do electric lighters form such a spark?
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    Calculating electric field produced by micro crystalline piezoelectric grains

    I found some examples of calculations on here. so thats good. a quartz crystal of 2mm size can produce a field at its surface of 44kV/cm^2. which from looking into electroplastic effect is very useable. Ceramics however tend to be most effected by electroplastic (EP)effect near their glass...
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    Calculating electric field produced by micro crystalline piezoelectric grains

    Hi, I'm researching a potential masters project involving incorporating piezoelectric crystals into a ceramic so that when a load is experienced the electric field generated encourages the electroplastic effect in the bulk phase so that it becomes more plastic and inhibits crack formation...
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