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Sensei last won the day on January 14

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585 Glorious Leader

About Sensei

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  • Favorite Area of Science
    Quantum Physics
  1. Visual Studio Express is free since at least 2005. Even if the latest version with the best features (theoretically) might not be free, older versions, or some crippled versions, are still available to download. I recommend downloading entire DVD, and burning it. For example Visual Studio Express 2005 and 2008 free crippled versions can compile C/C++/C# .NET Framework 32 bit executable, but cannot 64 bit (there is needed special hack to make them producing 64 bit executable).
  2. You rather meant "lambda cyhalothrin"..
  3. Google used to be good 15+ years ago. Now it's pretty much rubbish. Who will purchase keyword, is showed first. You can even check how much you need to pay-per-click for given keyword..
  4. Majority of living organisms after death are eaten by other living organisms. Their atoms, molecules, muscles, fat and even bones, are becoming part of other living organisms. Only organisms that died in quite abnormal way, f.e. drowned in swamp, frozen (f.e. mammoth), are becoming fossils. Soil, swamps, coal, are "fossils". Remains of long time dead plants. Calcium carbonate rock is fossil. Remains of long time dead sea living organisms with shells. They are no longer easily recognizable.
  5. According to Special Relativity, while traveling at relativistic velocity, photons coming from f.e. stars are blue-shifted (Relativistic Doppler Effect) and f.e. pair of matter-antimatter e- and e+ is created. Positron will annihilate with surface of spaceship.
  6. Small correction, double-slit experiment was the first time performed by Thomas Young around 1800. https://en.wikipedia.org/wiki/Young's_interference_experiment Davisson and Germer in 1927 just did version for electrons. https://en.wikipedia.org/wiki/Davisson–Germer_experiment
  7. Pseudo-code (sort of .NET Framework Managed C++) to search for topics-posts which have code you're interested in: for( int i = 0; i < count; i++ ) { String ^url = String::Format( L"http://www.scienceforums.net/topic/{0}-old-thread-latex-repair-suggestion/", i ); String ^buffer = System::Net::File:DownloadString( url ); if( buffer->IndexOf( L"[latex" ) != -1 ) { // log to file that post with index i has tag that you want to find.. } }
  8. Tragedy.. Using this forum stopped making sense.. It works at least 10 times slower than previous version. Any thread link click, and I have to wait 10-20 seconds to open any page.. It used to be instant just a couple days ago on old version of software (on 120 Mbps, with reliable ~90 Mbps!) OMG, there is no "preview message" prior sending.. ? That's the most used feature, so we're sure latex tags are properly showing.. This button on the right of toolkit, is some joke from older preview feature.. 10 seconds waiting and it is showing completely white blank page, instead of my reply.. No real "full editor"? Edit: when we attach archive to post, there is no download counter. Go back to older version from backup, when you have chance..
  9. If G = 6.67*10^-11 N*m^2/kg^2 Then why did you use .6*10^-11... ? I have no idea...
  10. The question is which Plutonium isotope is found, According to https://en.wikipedia.org/wiki/Isotopes_of_plutonium "The most stable are Pu-244, with a half-life of 80.8 million years, Pu-242, with a half-life of 373,300 years, and Pu-239, with a half-life of 24,110 years. All of the remaining radioactive isotopes have half-lives that are less than 7,000 years. "
  11. No matter if "winter will be coming" or "warming will be coming", overcrowded Earth, will have so many hungry people, who will eat other hungry and/or dead people, sooner or later..
  12. That's essential. Some people think they will go on diet, then lose weight, and then return to their normal unhealthy diet, and ass in front of tv, after a while... And then surprised because of yo-yo effect..
  13. The same can be said about proton and electron, from two initial particles, you have 118 elements, and 3142 stable and unstable isotopes, after fusion, radioactive decay, and other nuclear transformations.. The same can be said about chemical compounds. From the above 118 elements you have entire chemistry..
  14. Muscles are more dense than fat. You can have the same weight 80 kg as before, but you will look thinner. Walking and biking does not sound like a lot of training. Do you have 5-20 kg dumbbells? If not get them ASAP (adjustable weight), http://www.ebay.com/bhp/adjustable-dumbbells and watch one of these videos: https://www.youtube.com/results?search_query=dumbbell+workout
  15. Light is layman name for photon. Electric charge neutral particle. There is used little gamma letter in equations of reactions with other particles (looks like small Y): [math]\gamma[/math] Photon has energy [math]E=h f[/math] [math]h[/math] is Planck constant 6.62607004*10^-34 J*s = 4.135667*10^-15 eV*s f is frequency in Hz = 1/s In old times there was used letter v [math]E=h v[/math] some still use it. Other equation for energy of photon: [math]E=\hbar \omega[/math] because [math]\hbar=\frac{h}{2 \pi}[/math] and [math]\omega=2 \pi f[/math] [math]\hbar[/math] is reduced Planck constant. In one line it can be written y e hv wh yhwh Easy to remember Photon with enough energy, with frequency f>2 fc fc =1.23559*10^20 Hz (Compton frequency) can change to pair of electron-positron (matter-antimatter particles). It's called pair-production [math]\gamma + 1.022 MeV \rightarrow e^- + e^+[/math] Electron-positron pair can annihilate, giving photons back again: [math] e^- + e^+ \rightarrow \gamma + \gamma + 1.022 MeV[/math] Each of these photons will have energy [math]E=h f_c = 0.511 MeV[/math] Other interactions of photons with matter-antimatter has been presented in f.e. this video