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Externet

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Everything posted by Externet

  1. Is there any new breaktrough development of a material for better containment of helium in weather balloons ? Beyond mylar, with more durable containment, perhaps from nanothechnology ? Or,.... is there any new larger molecule gas, lighter than air which will not escape trough current porous materials in balloons ?
  2. Hi Marc. Having difficulty to discern solids which show significant expansion. If you have suggestions, please come forward. The force exerted by this one at a delta of ~20 degrees Celsius may not be useable to force enough expansion. http://i00.i.aliimg.com/photo/v0/449280688/Bi_metal_thermostat_spiral_coil_on_silicone.jpg Please comment on post #14 above.
  3. See no botanics or agricultural or gardening in the forums, so am planting it here... What happens or not happens in a plant growing upside down that seems not to affect its development, growth and productivity, while being so unnatural ? Getting ready several 3 litre soda bottles and a few commercial brand planters to experiment in the coming spring, and compare with the normal upside up in my vegetable garden. Tomatoes and strawberries are on mind, I would post progress pictures periodically. If there is a plant choice that you know would be more successful than others, or interesting to try, please suggest.
  4. Hi. In an attempt of exploring less complexity and difficult solid materials, let me make a parenthesis at this point, will return to the main solids expansion later. What is your opinion on following the electric route, and as bubbling from electrolysis is not promising, what about using ethanol or an even better behaving liquid in a thermally insulated sealed bellows. Heating it up will become gas causing expansion and buoyancy. Something like 'hand boiler' toys. A volatile liquid that can be easily gasified with little energy from a battery powered heating element. Which could be as simple/available or better performing enthalpy of evaporation than ethanol ? Propane, Acetone, Ethane, Carbon tetrachloride, Chloroform, Ether, Methane .... ? Under depth pressure of ~ 7atm = ~200 feet Will be back...
  5. Thanks again, Marc. Am thinking on your good suggestions, will be back. So far I see a problem with your paragraph " If the bladder is located before the wings, its volume change will not only provide the net up or down force, it will also put the nose up or down." The air volume change due to depth pressure or lower temperature in the nose bladder would not provide surfacing force, as the pressure will reduce the volume, making it dive instead. -----> The root of the problem is that at depth, there is lower temperature, and that causes air volume reduction, sinking it more, and; at depth, there is high pressure, and that causes air volume reduction, sinking it more. Then, to my poor brain, depth pressure and temperature are not useable to provide air expansion to rise to surface. We need the opposite action. I came up with an hysteretic mechanism for nose up/down : A long sealed pipe lengthwise to the fuselage, with a ball bearing inside and weak magnet end caps. Seems to me, sealed bellows are preferable to piston/cylinders. Will be back after digesting your post and evaluating the availability of fancy materials with expanding when cold property.
  6. Thanks, Michel. Your correct wording made a world of difference ! Great help !
  7. Hi. Did not pay enough attention when a 10,000 sq.ft. freezer was added at a facility I worked at many years ago. ...Remember a reinforced concrete slab poured on the ground, then a ~8" layer of styrofoam, and another reinforced concrete slab on top. Forklifts danced all over that floor with no problem. Am I missing details?; what is the building technique to avoid cracking/collapse with such styrofoam sandwich ? How is it done properly int the civil engineering world ?
  8. Thanks, Enthalpy. Very interesting. Such depth pressure piston actuated bimetal dome could shift the ballast position for nose up when a depth is reached, to reverse its action for nose down when reaching zero pressure at surfacing. Nice and 'simple'. The buoyancy cycling is left to deal with. If solar cells on wings/fuselage of the glider charge a battery, could bubbling at an electrolysis chamber triggered by a depth switch work? * ; purging them when reaching surface is sensed , enabling next dive. Surfacing at night, halts everything if battery sensors do not detect full charge. Unless other opinions come up with a bubbler/expanding chamber actuated by depth/temperature/light deltas. *Would bubbling volume by electrolysis be seriously impaired at depth, as to not consider such method ?
  9. Is there any commercial device used in industry, equivalent to mechanical hysteresis ? A device that snaps mechanically or hydraulically, to two states like a toy clicker, or a 'klixon' thermal switch ? -A mechanically bistable device like a wall switch, unstable at its center position-
  10. Thanks. It does not always show the "Attach this file" capability. [image below] This time did ¿? See attached. Retrying... perhaps will attach. Seems does not work on 'quick' replies...
  11. Hi. OK, call it engine. No problem there. But the word 'pixies' does not click in my poor English. An underwater contraption that will travel powered by delta pressure, delta light, delta temperature, delta whatever supplied by sea environment. To simplify, to come up with a device that endlessly dives and surfaces periodically by some clever automatism using the above deltas. I believe would take a 'snap' hysteresis action mechanism triggered from the delta extremes. Like a liquid that vaporizes under pressure and liquifies when not pressurized, as ideal dream. The 'snap' 'toggling' action is what I believe would make it work. Nitinol, solar cells and electrical actions, pressure driven actuators, anything in that line. Sample attached. But open to any suggestions Edited. Unable to attach a picture. Will retry. Edited2 : Lost in space on how to attach a picture on this new forum format. It was just a 'party clicker' image.
  12. Hi John. There is no need to have an engine to propel it forward. The sinking action with nose slightly down will make it advance forward. Same when rising, the nose slightly up will make it to continue advancing forward. Like an airplane with no engine (glider) The mechanism to make it buoyant and nose up could be an electrolysis bubbler running from a seawater battery. When the craft surfaces, bubbles bleed by either a solenoid or a needle valve held closed by its own float, repeats the cycle starting to dive. But there have to be other ways... http://i588.photobucket.com/albums/ss323/Innernet/P1010038_zps089b92e7.jpg
  13. Hi all. Picture a glider model, ballasted to stay near horizontal and near neutral buoyant when placed in the sea. When placed in the warmer water surface, with daylight and little depth pressure, some mechanism makes the nose go down, slightly decreases buoyancy and advances while dives. When reaches a set depth pressure, darkness and cold water, those cause the mechanism to toggle back towards being slightly buoyant and tilt nose up. It will rise and advance. When surfaces, little depth pressure, daylight and warmer sea temperature cause the mechanism to toggle towards slightly decreased buoyancy and nose down. It will sink again and advance. Repeat and repeat... The lengthwise center of gravity shifting and the buoyancy are the mechanisms that can be actuated by solar cells, pressure collapsible chambers/piston, temperature actuators, or whatever else you think may work . Some mechanism that increases buoyancy with cold/depth pressure/darkness/hitting bottom would be needed. Bubble generation and purge... or other clever methods. Come up with ideas,,,
  14. Or, put them all 24 / 7 into calculations to find the next winning lottery numbers. And I expect my percentage of wins, not of the power bills... !
  15. There is no trick, and 19 is wrong because it is wrong, being mathematics an exact science.
  16. 28 bottles come in seven promotional packs of three + one free; which is buying 21 and getting 7 free ?
  17. Are +/- 90 north/south latitude degrees, +/- East/west 180 longitude degrees, 24 hours per revolution; 60 minutes and seconds subdivisions being used when exploring and charting other planets ? Is the absence of the decimal system being carried to other worlds exploration in favor of the senseless duodecimal / sexagesimal / dozenal and earthly time divisions ? Would it be better to start using a rational decimal system for -say 100 hours with decimals time- per revolution; dividing a circle in 'new' 100 degrees with decimals ? Why yes and why not ? <Sorry. title should spell 'committed'>
  18. A zillion years ago, about 8th grade in school, the teacher was demonstrating something and put water in a vessel to boil on a bunsen flame. He placed a glass/mercury thermometer inside to show the reading. I was the only one who warned the teacher that could not the correct way to measure the water temperature, as the thermometer bulb was contacting the bottom of the vessel and would read higher than real water temperature. Then he held the thermometer by hand suspended, touching only the water with an embarrassed red face. Now am thinking if I was wrong. Would the vessel be at the same temperature as the water contacting in it, or would the vessel be hotter as I pointed because it was contacting the flame; or somewhere in between (Which would still be a higher reading) ?
  19. Clear ! Thanks. Then, if in cold air induction A + fuel B, we partially replace some A with some 'E' (exhaust gases recirculated into the intake), the fuel amount B can be reduced accordingly to the amount of oxygen as the amount of A is less. Some amount of E + less mass of cold A + less fuel B ---> E + C CO2 + D others The amount of E, controlled by the engine control unit ECU depending on the ambient air temperature sensor reading. Is that the way it is currently implemented , or exhaust gas recirculation EGR is used only to reduce emissions with no intention to compensate for extra fuel consumption in cold air temperature ?
  20. Thanks. Well, then, comparing same exact driving/road conditions, will winter cold use more fuel than hot summer ? ( having no fast valve closure implemented )
  21. Seems you have not checked / searched for existing equipment, like negative ion generators. One of dozens in the market : http://www.the3q.com/products/3Q-ELECTROSTATIC-IONIC-AIR-PURIFIER-w%7B47%7DDUST-COLLECTION-ROD.html And the chinese production : http://www.alibaba.com/showroom/air-purifier-ionizer-dust-collector.html I unplugged mine as the area around the wall outlet got blackened with dust particles
  22. It's been about 20 years since they do not manufacture automobiles any more; they make computers with wheels since then. The on-board engine control unit measures intake air mass by its flow and its temperature, and sets the fuel amount for combustion. Being cold winter air more massive, does it feed correspondingly more fuel then, than in hot summer thinner air ? If yes, preheating intake air would decrease the fuel ratio, If not, is it because the oxygen content exhaust sensors action ? Hey ! but if there is more air mass intaken, then the 14:1 ratio could not be sustained ! What am I missing ? Is the throttle position working less open in winter for the same performance, or there is another compensating control ?
  23. Smile now ! - as tomorrow will be worse... Shifting labor into manufacturing robots labor will not suffice filling unemployment, and that is if building the robots does not move to China to make it really worse. Corporation greed will always push towards less expenses and more profit by selling crappier-short-lived goods, if 'goods' is the right word.
  24. -- When there is cold weather as in winter, does the atmospheric pressure 'shifts' to a higher range than in hot summer for the same clear sky ? It would make sense, as there is denser atmosphere when cold. -- When the weather reports say as example 'northwest wind' ... do they mean coming from northwest or heading towards northwest? Is there a standard meaning ?
  25. What is not recycled they want it burned ? Hospital refuse ? What else ? The volume of such for the $ amount of such incineration plant does not click well. Let the risky refuse producers install / do their incineration with their $ and do not put the hand in the taxpayer wallet; that money can be better used. Extending recycling to a finer point should be the choice.
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