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A glass rod can have higher tensile strength than iron if it is polished properly. So a diamond rod with a perfect crystal lattice will have great tensile strength. But probably not the greatest, maybe a rolled up graphene rod would do better, as more of the bonds can take up tensile force at the same time. A simple chain of carbon atoms with double bonds ...

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Strength of materials is affected by defects. A perfect crystal of iron would be extremely strong. Once a crack starts, it is not so hard to make it advance one atom deeper. Think of tearing open a plastic bag. Much easier once the tear starts. Brittle materials can be easier to break because they stretch less. It is easier to tear a sheet of paper than a ...

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Actually the data presented by You show that iron/steel is more brittle than diamond. Precise tensile strength of diamond is unknown, however values of up to 60000 MPa have been observed. Typical values of tensile strength of iron/steel varies from 100 to 11000 MPa. Therefore diamond can withstand more than iron/steel.

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You can also use Diffractive Optical Elements (AKA Holographic OE) implemented as phase plates. This, to start, provide a uniform reflection-loss transversal profile, as they are flat. They are also thin, so if you are considering bulk absorption, too many elements, etc., this may help. In the cons side... you need monochromatic light. But I think this does ...

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Probably too late to help your particular issue, but here goes. First, there are a lot of possible ternary phase diagrams, most of which are not technologically useful (yet), so there isn't much funding to go look at them. Heck, there are many binary phase diagrams that are not really well researched (I was surprised this week to find that the Pd-Pt ...

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Draw the graph of $\frac 1 x$ . You can see that it is a decreasing function for positive $x$. Hence conductance decreases as resistance increases. We could have defined conductance as any other decreasing function also but $\frac 1 R$ appears in many equations so we defined it that way. You might want to look at derivation of $J=\sigma E$ to get better ...

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The electrical resistance of an electrical conductor is the opposition to the passage of an electric current through that conductor; the inverse quantity is electrical conductance, the ease at which an electric current passes. Consider resistance of $0.0001$ ohms, what is $\frac{1}{0.0001}ohms$? It is equal to $10000$ siemens. I hope this helped you in ...

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Conductance is indeed defined as the inverse of resistance. $$G \equiv \frac{1}{R}$$ To see what this means physically, consider that when the resistance is large (i.e. it is "difficult" for current to get through), then conductance is low, and when resistance is small (i.e. it is "easy" for current to get through), then conductance is high. There's an ...

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Any ordinary LED (a light emitting device) would probably do this, by sourcing an opposing voltage when exposed to light (and the effect / voltage would also be bigger if the source of the light contained the wavelength that would normally be emitted by the device).

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I would make a flag from iron oxide (red), platinum (white), and lazurite (blue). It won't wave in the wind, but it will retain the color. The base would be a platinum plate, of course. I would made a really large one, so that people wouldn't complain that it was too cheap.

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The Apollo 11 flag was included almost as an afterthought. It was just a month or so before liftoff, and someone at NASA slapped themselves on the head and said, "we need an American flag to plant at the landing site!" Someone rushed out to a local store (Sears?) and bought a standard nylon flag, which went to the Moon. Besides being bleached out by solar ...

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the resolution is kλ/NA k is a technical factor

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This is going to be a bit of a long answer, so please bear with me while I develop the explanation fully. You can use energy arguments to prove the bounds on the Lamé parameters (and therefore, the Poisson ratio). Here is the free energy function for a linear elastic solid: $$\psi = \mathbf{\epsilon}:\mathcal{\mathbf{C}}:\mathbf{\epsilon}$$ where ...

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your first equation applies to tension & compression, the second to torsion. http://en.wikipedia.org/wiki/Torsion_(mechanics) the link also shows what theta is. The point where plastic (permanent) deformation occurs. Where it is on the stress strain curve depends on how you define it, wiki shows the various methods: ...

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In principle yes. But to make a good $\text{Zn}_3\text{N}_2$ homojunction LED you need the capability to incorporating both p-type and n-type dopants (normally oxide materials are naturally n-type) which might not be possible. From what I have read, this material has been proposed as a way of making p-type ZnO (which is naturally n-type) by a post growth ...

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Natural diamonds are slightly harder than synthetic diamonds. This is very commonly known in manufacturing (diamond-tipped drills etc) and there is plenty of engineering resources on the subject. However for jewelry purposes, a trained jeweler can almost never pick out a real vs synthetic without special tools for that purpose.

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