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Externet

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Everything posted by Externet

  1. Hi. And where in the land -or soil- did those 'several' studies measured the temperature ? Atmosphere boundary soil surface, 1cm. below surface, 10 cm below surface, 100 cm below surface ? ... I would venture to say that measuring temperature any less than 15 metres depth would be affected by a cloudy or sunny, or snowy, or rainy day in such way that uncertainty would take over such theory. After an earthquake happens and heat is released, the propagation speed of heat in soil is so slow and usual fault depths so great, that such land temperature change would show something months or years later, if ever, also due to heat dissipation and attenuation.
  2. For the 'old' part, I bought 40 years ago, and still have, a kit like this, but the box is orange color and marked "Radium" It behaves as you say about the luminosity, charging by light and losing its 'charge' in about a minute. Perhaps that is what you are asking for ? ----> http://www.orau.org/ptp/collection/radioluminescent/favoritetouchupkit.htm
  3. Hi. Is this correct ? <Polyethylene terephthalate PETE is soluble in phenol, chlorophenol, nitrobenzene and dimethyl sulphoxide> Is there others ?
  4. Geiger counters do not work on firefly guts squished on the floor, or do they ?
  5. Well, if after evaluating samples and not satisfied, an alternative : ---->http://www.aerogel.com/markets/industrial-hot-products.html Check Aspen and Thermoblock brands. Cannot tell if prices will be convincing.
  6. lassez : It is not like window or bottle glass. It is the nearest artificial thing to pumice. I have handled it and weighs near to nothing. Smashing it with a hammer produces crumbs as old bread would, with no dangerous edges, unless you go barefoot... Iñigo can order samples in blocks form, use staggered for covering the hot thingy and evaluate, or carve them with an abrasive wheel-stone-disc if needed to fit unusual surfaces, or leave some air gap to the insulated surface.
  7. Hi Iñigo. Give this some thought : ----> ----> After time stamp 4:30 ----->
  8. OK, I'll bite. In my opinion, garment production by robots in USA would not beat chinese factories. It may make it more expensive than currently is from any existing sweat shops in U.S. Because if those robots are made in USA, * with strambotic costs to produce them, their absurd maintenance and repair fees. (or do you want to buy chinese robots ? ) And the still absolute necessity of personnel handling transportation in and out the factory, feeding the robots; administrative and hidden costs, (or do you want to employ chinese inmigrants ? ) designing the products; (or do you want the chinese to do the design patterns in vogue ? ), the cost of fabrics (or do you plan to import the fabrics from China ? ) The parts to put together/fix robots would likely come from China also, by the same reason * above In the remote chance that U.S. robotic garments come down to competitive prices, the result would be outsourcing to other chinese in the robot manufacturing industry instead of the sewing chinese labor. { Skidding off topic, the problem is in the too high US salaries driven by a multitude of factors and greed. } Having worked in 'automated' electronics factories in US, robots handle only the repetitive actions, yes, at a much faster speed. And those factories I worked at, ended closing doors and outsourcing the production of equipment similar to laptops and iphones to the $%^&@ orientals. No, unable to find a job for 2 years. {Skidding off topic again, certain protesters against the chinese being paid a couple of dollars per day working for US corporations, do not notice that a pound of meat is 20 cents there and in US is $8.999 a pound. So who is being ripped off the most ?} Sorry, delete the rant if necessary.
  9. Hi. Is there a method of calculation for a magnetic field distant from the magnet itself ? Say: ================================================X <--- long iron bar N magnet S ================================================Y <--- long iron bar A magnet at left end, of known field strength, intimately attached to polished surfaces, between long iron bars, produces a magnetic flux between far right points X and Y. How are the bars length a factor in the value of the flux at the far end ? For sure iron purity, spacing, thickness... have an influence too; but let's discuss only the length. Would there be a zero flux at an infinite length ?
  10. Hi. Is the exhalation of CO2 by plants in periods of darkness -as night time- a necessary biological process for their proper growth, or are unaffected growing better/more with full time natural + artificial illumination ?
  11. Thanks. I understand the convenience, elbows, shoulders and hands positioning... not part of the subject. The thing is comparing with another wheelchair with the same base width. Take a 'normal' wheelchair and bring the high of the wheels inward, with same center of gravity. How that improves stability?
  12. If the center of gravity is kept at the same place; the footprint of solid tires is equal and at the same distance, What are the effects of angling the shafts as in this setting, instead of / compared to the 'normal' horizontal shaft Why if the answer is stability ?
  13. Just tried. With isopropyl alcohol at 50% into gasoline. Water does separate. So gasoline has pure alcohol dissolved in it now. Is it fine to suspect the same for other alcohols ? The ethanol that is being added to commercial gasoline has to be very pure, or the bottom of fuel tanks in automobiles would have water; right ?
  14. Hi. Which wood would yield better/more methanol; 'alive' freshly cut timber or 'dry' old dead wood ?
  15. Hi. Ethanol mixes with gasoline, Water mixes with ethanol; What happens if ethanol with some water dissolved in it is mixed with gasoline ? Is there separation ? What are the components that separate ? Is there a ratio when it does not separate ? What if it is methanol ?
  16. Thanks. If it is supposed to be called another way, I do not know. But if a god somehow 'tells' his disciples/followers/leaders to kill a certain population, seems to me it is a religious crime. Would that god be guilty ? Would the fanatics taking blood on their hands be guilty ? Not in front of secular law, but on ethics, as to judge. From the point of view of fanatics, killing may be very well justified/'legal' ; from the point of view of victims, well, the opposite. Fanatics may behave differently as to recognize what may be legal or not. Would that make them equally guilty or not guilty ? Would that lack of recognition/awareness change opinions/concepts about judging their behavior ?
  17. Hi. When a fanatic, group of fanatics, obeying a recognized leader and such leader obeying a god's command, commit genocides, who is guilty ? The leader; the god; the executors of the crimes; or all of them ? Who , if anyone, should not be charged / judged with the religious crime ? (As by following orders) In the case of the military, same question, without god... The top chief, the field commander, the soldiers...
  18. Hi all. Never seen such before yesterday. It is soft, rubbery, wet looks, bright orange, white base, black top. Today it has its point bent down, but still there. There is no more around, nor parts of it as if it was missing something. What is it ??? ----> http://i588.photobucket.com/albums/ss323/Innernet/P1000982.jpg Other pictures ----> http://i588.photobucket.com/albums/ss323/Innernet/P1000983.jpg ----> http://i588.photobucket.com/albums/ss323/Innernet/P1000984.jpg
  19. Thanks, gentlemen. The intention was a chemical to promote dislodging, not dissolving the stuck aluminium dust inside as it would risk the core material too... Well, will try some miscellaneous household mild products and simultaneously attach some mechanical vibration during backwash, as there is no access to mechanical cleaning. If there is a "Do not use such !!" opinion, let me know. Otherwise, I will end at the radiator store for a new one.
  20. Hi all. At some point a car coolant received a dosage of some aluminium powder 'supposed' to do some good. Which way would you suggest to backwash the radiator in order to remove any obstruction caused by such powder ? Would detergent, or borax, a solvent, or gasoline or something else work better without harming the aluminium cored radiator which is healthy but assumed semiobstructed ?
  21. Hi. Which metal made thick walled container, [not foil] about the size of a coffee cup with a lid can be put in a microwave oven so the metal will heat up, heating its content by convection inside ? Would an iron, stainless, aluminium, brass, copper... cup work without damaging the oven nor making fireworks ? Or some other material that will absorb oven microwaves ? Would its shape spherical, no sharp edges... be preferred ?
  22. I believe a limiting factor in developing higher efficiency engines is sticking since day one, to use water as coolant. My point is replacing water based coolant in ICE engines, -An oil cooled engine- with the most convenient transmission fluid. or diesel, or kerosene, or transformer oil, or refrigeration oil, or hydraulic fluid, or some other petroleum derivated, or a blend of the above -but no water content at all- Which can: - Eliminate boiling at 'normal' operating temperatures, - Eliminate rust progress or prevent it, - Eliminate pressurized circuits, - Eliminate freezing, no specialized orange, green, whatever coolant additives, - Increase efficiency with hotter combustion chamber if desired, - Even used transmission fluid at $0 is good enough, - Better heat transfer at hot surfaces due to increased wettability - No more overheating/blown head gaskets perhaps ? - What else ? The thermal conductivity and viscosity properties of some thin oils as transmission fluid that may be near to water, as cooling is its primary task in a transmission, which can run hotter than an engine. Now, are the considerations to observe : - Hoses should be oil resistant, not the kind meant for just hot water, obviously. - There is some rubber and seals in engines cooling passages; as there is rubber inside transmissions too. - Larger volume radiator to compensate difference in heat transfer parameters compared to water ? - Faster circulation pumping to compensate difference in heat capacity compared to water ? - Different pump impellers to compensate difference in viscosity compared to water ? - What else ? -----> In other words, how would you, thermodynamics expert, replace water or water-based coolant with a petroleum-based coolant for an ICE engine ? Few figures I have been able to find: Water Heat capacity = 4.2 @ 100C Thermal conductivity = 0.58 @ 100C Viscosity @ 55C = 0.55 cSt 20W engine oil @ 100C Heat capacity = 3.1 cP Thermal conductivity = 0.15 Viscosity = 6 cSt Kerosene @ 100C Heat capacity = Thermal conductivity = 0.15 Viscosity = 6 cSt Transmission fluid @ 100C Heat capacity = Thermal conductivity = Viscosity = 3.5 to 7 cSt Diesel fuel #2 @ 55C Thermal conductivity = Heat capacity = Viscosity = 1 to 4 cSt Therminol 66 transformer oil Specific heat = 0.4 Viscosity = Refrigeration oil Thermal conductivity = 0.14 Heat capacity = Viscosity =
  23. Hi fellows. What are the parameters of consideration to evaluate the suitability of a fluid used as a closed circuit circulating and pumped cooling media ? Thermal conductivity, specific heat, thermal transfer index, heat capacity, viscosity... what else? The circuit to be a machine that gets hot and a heat exchanger to cool the circulating fluid. To replace a coolant such as transformer oil with plain water, or diesel, or transmission fluid, or other suitable ones. Or reverse, as replacing plain water coolant with kerosene, or very thin oils with viscosity near water.
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