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BhavinB

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Everything posted by BhavinB

  1. No...the spacing between the ribs is too large to act as a diffraction grating.
  2. BhavinB

    crystals?

    hahahahahahahaha...this is hilarious. But, in a very indirect way, they use solid state crystals in lasers which in turn creates ultrafast, high peak power optical pulses for fusion. I think.
  3. There is some small amount of energy lost to vibrations. And an atom will not emit only at its transition frequency, but some finite region near that frequency. This is called the 'transition linewidth'.
  4. Not sure what your question is...can you rephrase?
  5. There are references at the bottom of the wikipedia link, here's probably what you're looking for. C. Brans and R. H. Dicke (1961). Mach's principle and a relativistic theory of gravitation. Phys. Rev. 124: 925. EDIT: After looking up this paper, I noticed its been cited 1670 times by OTHER peer reviewed papers. Wow.
  6. BhavinB

    Lightning

    Look up Paschen's curve and the dielectric constant of air...then you can grasp just how much a voltage difference you'll need to create a sizeable 'bolt'.
  7. This sounds like a calibration problem. Why don't you measure the resistance at many displacement points and plot it? Should give you a rough idea what the curve would look like. Then you can do a curve fit to some type of equation thats similar.
  8. Ternary phase diagrams use a 2D method to graph four dimensions....sort of. http://www.sv.vt.edu/classes/MSE2094_NoteBook/96ClassProj/experimental/ternary2.html
  9. ^^ Just to add to your answer is mentioning Fermat's Principle which basically says the path light takes from A to B is the shortest possible one.
  10. I thought Microchip has a free assembly programming software?
  11. Anyone here know anything about the Box-Wilson method of Statistical design and optimization of experiments? I have a few questions about finding the path of steepest ascent.
  12. Actually, what you ask is a very complicated question that is still the topic of research. In research, the topic is called "quantum measurement" and many theorists are looking into a generalized Schroedinger Equation. In this scheme the measuring device has an interaction with the general SE such that it collapses its waveform. So really, its not a trivial question. In fact, you should feel proud knowing that most people who take QM don't question that property at all (myself included).
  13. I remember a physics lab topic was to determine the properties of the neutrino using beta decay. One of the properties I had to find was the mass of a neutrino...lol. Interestingly, that was around the time when scientists started believing neutrino's might be massless.
  14. +1 for Peltier coolers. I use Melcor as my source http://www.melcor.com
  15. It all depends on how big a chamber you want this to happen in. There is a cleanroom device used at my university. It is called a Rapid Thermal Processer (RTP) or Rapid Thermal Annealer (RTA). The chamber is made small enough to encompass small wafers. This might also be a technological consideration. Nonetheless, the device can ramp at 80-100 C/s.
  16. There are no polymers with inherent metallic conductivity. There are however several conjugated polymer/nanoparticle composites which come close. Really close. Just one or two orders of magnitude off (for reference, a semiconductor is 5 orders of magnitude lower than metals). Gonna be an interesting decade I think. But because the materials and processes are progressing much slower than Moore's Law, there will come a point where the density of transistors won't get any larger for some time. Instead, new computation concepts will increase computing power. We are already seeing it in todays newer processers: 64 bit computing, dual cores, increased pipelines, asynchronous logic etc.
  17. second-order nonlinear optical property means the materials refractive index varies with light intensity. Usually we believe the refractive index is a constant, but at sufficiently high intensities, it isn't. so n=n0 + n2*I where I is the intensity of light. I don't know anything about mechanoluminescence. You'll have to describe the property.
  18. Defects do not cause the non-centrosymmetricity. It is inherent in the basis of the crystal. Definition: A crystal is defined by a set of lattice points and a basis. The lattice points are defined by three vectors. A basis is placed at each point. The basis can be just one atom, two atoms spaced a distance apart, a molecule etc. In the case of a crystal that is not centrosymmetric, the basis also has no inversion symmetry (translating all points to their negative does not give the same basis). Also, if the lattice has no inversion center, then neither does the crystal. Here's a webpage with a picture of the 32 crystal classes. 21 have no inversion center. http://newton.ex.ac.uk/research/qsystems/people/goss/symmetry/Solids.html Interesting to know also that alot of other properties cannot happen in crystals with an inversion center. For example, pyroelectricity and piezoelectricity. Also, a crystal with an inversion center cannot have second order non-linear optical properties (if that means anything to you).
  19. Assuming you can somehow sustain so many people, there are a few issues that you can't ignore. a) You can't build this on earth, it would have to be assembled in space. And as of now, doing such is beyond us. b) The ability to get such a massive enclosure to move and maneuver (and slow down) at appreciable speeds is also beyond us. c) Money may be a man-made thing, but human hours are not. Money in its basic form represents human effort and time. Although there are economic factors to somethings cost, basically it comes down to how much time someone spent on something and how much they value their time. You can't ignore this basic fact of existance. So...as Severian said, who is going to 'pay' for this?
  20. I remember reading somewhere that you can generate a pseudorandom address of an internet data packet which is then used to create a pseudorandom number based on the data inside the packet.
  21. Ummm...I thought metals (electrical conductors) have lower specific heat compared to insulators (non-electrical conductors).
  22. 'Gravity at center' and 'Center of gravity' are different things. Yes the 'gravity at center' of a sphere is 0 in all directions, but the 'center of gravity' (and the center of mass) is at the exact center of the sphere.
  23. When you say "barely seen with the naked eye" could mean a robot thats a micron (or several) in dimensions. I think such a 'robot' is more likely within 2 decades or so. But when we say robots that are sub-micron, well, thats asking too much from scientists. True nanotechnology lies in using nanoscale devices and materials for our benefit. For example, I'm working on a quantum dot semiconductor laser. Although the laser itself is millimeters in length, the dots themselves are nano scale making the device "nanotechnology". This is how we'll see nanotechnology affect our lives.
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