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Externet

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Everything posted by Externet

  1. Hi. What harmless material attached to a moving object or animal, could be useable for tracking by detecting its emission of particles, waves, radiation or anything from the largest possible distance by modern sensing technology, without being electronic at all ? Sort of some tracer to locate/find which in thousands of packages or vehicles passing by carries such material inside ? Like the body heat detection used from aircraft while searching for lost persons in a forest, but not being obstructed by common materials, trees, buildings, and producing a recognizable signature. Miguel
  2. This black sand at a Pacific seashore (not on fresh water rivers) is highly abundant, but has never been tied with precious metals. But its titanium content is large, as heard from knowledgeable people. A good way to magnetically pick soils is by putting the magnets at the bottom of a plastic bag, and removing the bag to collect, the material falls off leaving the magnet clean. Surprisingly, if you look closely with magnifier, many transparent grains of sand are equally attracted by the magnet. Don't know if differs from the black sand composition found on gold bearing areas. Miguel
  3. Can you discern if the black sand picked is not Ti binding with Fe? It's one of those things heard as a kid; the local portland cement factory uses black sand collected from beaches as part of the recipe to improve the clinker. Miguel
  4. Hi. As I know nothing in the subject, am asking if isopropyl is inorganic, and which other alcohols are produced from inorganic chemicals not derived from petroleum. Thanks, Miguel
  5. Hello. Being human diet needs varied, what would happen with an almost only protein diet ? (plus water) Is there any study, or experiment with results of consumption of only -let's say boiled egg whites- even for a limited time of a week? Miguel
  6. Hi. Trying to rephrase: When does a chick starts developing its own body warmth ? A recently (fertile) laid egg does not have its own warmth generation; receives it from the parent. A just hatched chick does. Somewhere in between, the warmth generation starts. Gradually, I suppose. About when or at what embryo development stage? -Thanks for the information; I thought that some animals and living organisms did not have any body heat at all- Lizards and insects I touched are quite cold. Miguel
  7. Hi. A just hatched chick already does have its own body warmth, does it? And when does it start developing warmth ; days before hatching? hours? Miguel
  8. Hi. To turn 1Kg of water at 20ºC into ice at -10ºC, is this calculation correct? : Cooling the water 20ºC = 20 x 1KCal = 20 KCal Freezing 1 Kg = 80 KCal Cooling ice 10ºC = 10 x 500 Cal = 5 KCal Total = 105 KCalories must be extracted. How to calculate the same under 50 mm Hg vacuum ? Miguel
  9. Hi. If it was a mercury column instead of water, then the vacuum chamber will contain mercury vapor. Is the 760mm of Hg actually the barometric pressure minus the Hg vapor pressure at that temperature? If yes, the atmospheric pressure standard of 760mm is a wrong figure because of the unacounted Hg vapor. The real figure should be higher ! In other words, the barometric standard changes with the Hg temperature ¿? Now, to some misconceptions... I do not have it clear... the void is not really total vacuum as I thought, and the standard is not ? If the liquid in the column was some very special fluid not releasing any of its vapor at all, would there ever be a void above it? And to make things harder; would a suction piston move effortlessly attempting to expand vacuum in outer space? Can a volume of nothing be expanded to a larger volume of nothing ? Miguel
  10. Hi. Torricelli's barometer is water in a tube, 34 ft (10.4 m) tall column. The space above the water surface in the tube is vacuum. Isn't the water surface supposed to boil at room temperature under that extreme vacuum ? What about the rest of the water column... progressively less boiling with depth ? And does that boiling water fill the vacuum space with vapor becoming no vacuum any more ? Then what? If vacuum is not perfect anymore, the water column starts decreasing its height? Miguel
  11. Hi. What liquid in which diameter capillary tube of what material would rise the most ? If the vertical rise for a given set is let's say 100mm; and at about 90mm of the capillary column the tube bends 180º downwards as siphon... ¿ will it drip ? Miguel
  12. Hello. Can we make a list of typical household and over-the-counter chemicals that are obtainable without "prescription' in supermarkets, hardware stores, but not from chemical specialty suppliers ? Like: Sodium bicarbonate Rubbing alcohol Acetic acid (vinegar) Turpentine Acetone Gasoline Kerosene Diesel Naphta Butane Sodium chloride (salt) Paint thinner (whatever it is) Sodium hipochlorite? (the water softener stuff) Epsom salt Borax Graphite (pencil leads) Oils Methylethilketone Cyanoacrylate Please add, rename properly and do corrections... Miguel
  13. Hi. Any suggestions on which household chemicals can be used to restore the bright finish to aluminium parts ? It is for my automobile engine; aluminium parts used to be shiny and after washing with degreasers lost its new appearance, dull grey now. Nothing of real concern; but would be great if can be restored with something from under the kitchen sink pile of stuff... ...and your brains... Miguel
  14. Hi. If a container had a 100% perfect reflective interior, sort of a thermo; could light be stored in it ? Miguel
  15. Hello everyone. ¿ Any suggestions on which chemical doped with cations could be applied as a paint, yielding a semiconductor structure similar to silicon when dried ? Thanks, Miguel
  16. Two identical ships next to each other in the middle of a river heading against the current; one at full throttle developing 1000 horsepower just counteracts the current and does not advance at all. The other is anchored. How many horsepower does the anchor produce ?
  17. Hi. Yes, you may say a concrete block to scrub with. Was more inclined to a (finely powdered) alka-seltzer type of compound to be mixed dry with Portland cement; to release microbubbles at the moment of wetting the mix.... A cheap sodium bicarbonate type of compound. Miguel
  18. Hi. What compound would be the most convenient to mix with mortar to expand it to a very lightweight pumice type end product with non-toxic microbubbles? I say micro because I believe that if the bubbles are somewhat large, would surface too easily before the cement cures. Thanks, Miguel
  19. OK. Thanks for responding. The ions would cross the barrier even if the liquids are non miscible ? If the bottom liquid with its +dopant is applied as paint to a metal substrate and left it dry, then the non miscible other liquid with its -dopant painted on top; when dry wouldn't it be a PN junction ? Miguel
  20. Hi everyone. As a doped silicon junction generates a current when photons strike, how could a pair of ¿non-miscible? thin liquid compounds be formulated to generate current under sunlight, each with its electrode ? electrode1 -------xxxxxxxxxxxxx floating layer electrode2 -------zzzzzzzzzzzzz sunken layer Miguel
  21. Hi. What interesting thing to do with it ? It's a light green powder in a glass vial; the box is marked as "radium" and intended to mix with a clear glue also supplied in the kit. Am still alive (I think) after that stuff has been in my house for 30 years. Miguel
  22. Then, from your statement, if aluminium is sawed off/scraped while under water, will yield a nearly explosive or violent reaction ?
  23. Hi. Just found out that acetic acid (vinegar) applied onto recently scraped magnesium will bubble and fizz. It will not happen on aluminium. That's a household chemical easy to try with. ¿Does it make sense? I will try later myself... Thanks, Miguel
  24. Hi. Re-trying to reply, as the text dissapeared while posting... Try a black-matrix LCD VGA display (I have a couple around, has normally shut pixels and will open the commanded ones) with the backlight panel removed, driven on a .pps -slide show- PC program to select a sequential chain of apertures and its locations. I do not see any problem with the source being infrared, but cannot tell for sure what opacity would be achieved. With plain white light they are not that much of opaque, it may actually be better with IR, or polarized IR! Good luck, Miguel
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