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Thanks, jdurg ! As am not thinking this for a batch type/test tube laboratory centrifuge, but for a continuous-flow industrial type as in: http://www.alfalaval.com/ecoreJava/WebObjects/ecoreJava.woa/wa/showNode?siteNodeID=5381&contentID=-1&languageID=1 [These machines run at 10 thousand G's, I know their performance from the years I worked at a fishmeal plant where these extract oil from fish 'broth'] ---> Can I interpret your answer as... A centrifuge can be used as a desalinator if fed with seawater ? Would ions respond sustantially different to extreme gravity than water itself ? Which would float, ions or water ? Miguel

Thanks. Well, but if the swamp is drained, it is no more. I mean as in wetland state, gets ignored and stays undisturbed. Or... is there some crops from such places? Miguel

Hello. Can common salt be separated from brine with a centrifugue? How do Cl- and Na+ ions densities compare to water molecules and are affected by hyper gravitational forces? Miguel

Are swamps left alone because are useless for cultivating anything ? Are there any fruit trees, crops or something swamps produce besides mosquitoes ? Miguel

Hi. Unsure if this is the best place for the subject, but, which animal shows the most 'intelligent' behavior ? (life, strategies, skills, self-sufficiency, activities... at its animal level) Miguel

Depends on the location of its center of mass. When a plumb line from its center of mass falls outside the base footprint, it will fall... unless it is glued to the soil. Miguel

Wrong. The well can be much deeper than the surface of its water. That is not even the distance to the water level in the well. The unknown size of the stone poses a much more complex calculation, as the larger it be in relation to the unknown well pipe diameter, causes more air cushioning its falling velocity. The unknown gap between the stone and the well pipe wall can change calculations considerably. Miguel

Shallow geothermics. Always wanted to implement it; now I can and am ready. There is now an unused fresh water well in my backyard, has a suction pump, thus should have a check valve at the bottom of the pipe, then I believe is not 'deep'. Canot be over ~30 feet. (Coastal North Carolina) The well water temperature is somewhere near 60ºF. Inserting an automobile radiator in the return side of the central heating/air conditioner duct, fed by the closed loop from a U in the well with a recirculation pump, should supply the dwelling with ~60ºF air, to the capabilities of BTU exchange minus losses. In summer, for a ~85ºF weather, a delta t of around 25ºF; pretty decent, no airconditioner would be needed. Seems doable. In winter, for a ~35ºF weather, a delta t of around 25ºF ; pretty decent, not much extra heating requiered from the outputted 60ºF to reach 70ºF desired BUT: If the central heating system additional work heats up the house to ~70ºF; about THAT would be the return air temperature; rendering the geothermal plan unuseable, as if the inserted radiator has 60ºF, it would be counteracting and cooling a delta t of 10ºF instead ! Am I wrong somewhere? How could this case be used in winter? Many geothermic sites promote supplementary heating in winter even with not that much delta t. I do not see it possible now:-( . Is it about maintaining the dwelling at 60ºF while nobody is at home, then turning on the standard central heating during occupation hours? (And shutting the geothermal off then ?) D----->R------>Rad----->H----->S----->D For D=dwelling; R=return duct; Rad=radiator; H=heater; S=supply duct Thanks, Miguel

Hi. Too many years since left university, cannot think on how to create the equation. An 8 feet long string, (or rod, or sheet) forming a parabola. The shape will be somewhat like a flattened U. I want the focus at the center between the upper ends of the U. (Or, at the lower tip of the accent on this letter Ú ) How do I come up with the equation? -It's to build a reflector with a 8'x4' sheet and be able to mechanically support the focus between its ends- Miguel

What can be done with a bunch of spent Lithium-ion cells I have ? They are half inch diameter, 3 inches long, out of laptops, should provide a decent amount of Li. Miguel

Hi. I would attempt registering the spin using a storage oscilloscope. Borrow, rent, or... It will keep the waveform for analysis of which sampling approach is more convenient if you still want to involve a PC into it, or if the sensor needs modification to obtain a better amplitude/detail. Miguel

Hi. Be careful not to confuse the terms 'vapor' and 'steam', often frequently misused. The second is the one created over 100 ºC. The first happens at any conditions, as clearly, clouds are not at that temperature. Miguel

They are proposing the same here under the San Francisco Golden Gate bridge; deep enough and massive flows. The problem is reliability and maintenance. Anything submerged in seawater is prone to failure by corrosion and carried debris. Technology and construction must be very reliable for success. Miguel

No, but use protection against the soda bottle exploding...

Truly, envious congratulations CurvKyle on your hearing abilities; but I believe you failed. How do you know the speakers you used for the 'online' hearing test are capable of "24Hz" ? Did you make a mistake meaning 24KHz? Well, 24 Hz is not bad either. herme3: Mostly yes, about 97% of radio stations do it in varied amounts. It is compression, limiting, clipping, multi audio-band equalizing, etc. Soft sounds are pushed up to FCC limits bringing a steady level with little dynamic range (difference between soft passages and loud ones) of about only 7 to 10 decibels. A recognizable extreme example is watching a TV movie, were dialog is at nearly the same level of guns shooting. Yes, sure:rolleyes: . Convincing to those who have never heard a real shot. Of course if the TV speaker was to reproduce the sound level of a shot, it would vomit its guts out at the first .22 cal firing. The specialized audio processing equipment is at: http://www.orban.com. There is some instructive audio articles worth reading, but you have to dig for them at the site. Edit- added : the document is titled "Audio quality in the FM plant" Miguel

My jaw dropped to the floor last week watching a television documental intervieving two blind kids riding bicycles ! and playing basketball ! self guided by continuosly clacking their tongues and listening to echoes. They are able to discern parked cars, pedestrians, obstacles. Perhaps if you do a deep search of the net, something may be transcribed here. It is well worth the effort to find such article. Miguel

Hi. I like your question. Perhaps because I can answer. The difference from FM broadcast and CD is barely audible if you can hear over 15 KHz, which I doubt unless you are 10 years old... If you disagree, do not argue and get a hearing test first; then we can discuss the subject. The Federal Communications Commission FCC sets 15 KHz as maximum frequency response for a 200KHz channel bandwidth for FM stereo stations to avoid interference with adjacent channels and limits spurious emissions from overmodulation. There is many CD recordings that are much worse than FM broadcasting, and there is many radio stations that sound much worse than a CD. There is NO norm. And beyond, there is millions of ears each with a different opinion about what sounds better. Radio stations do use audio processing to make their signal louder by compression and other effects to gain dial market competitivity, deviating from flat and realistic audio reproduction. CDs are too often also recorded with coloration and effects to suit producers demands, disrespecting fidelity in an attempt to make more $ by leaning towards trendy sounds. So, you can't cut all cheeses with the same knife. ALWAYS remember the definition of distortion: Any and all difference from the original sound source. Don't tell me that singer XYZ sounds in front of you the same as in its tricked, equalized CD recording. Miguel Audio-recording engineer -13 years working on audio processing equipment for broadcasting-

Hi. Investigating a little deeper, appears that the compound is ZnS with Cu or other dopants to select the color given off. And seems the nasty habit of naming things wrong as "phosphors" when there is no phosphor at all strikes again. That pisses me off. Misleading information using the word phosphor when they should say plainly luminescent. I do not have a plain old green monitor to aim my IR laser onto it and check if the CRT uses the same compound. But that works with electrons, not photons... I'll try on my oscilloscope. The powder coating inside fluorescent lamp tubes, what is it, exactly? It gives off white light when irradiated with UV, IR, plasma, ions, electrons or by what from inside the tube? EDIT- added- Found this: (Ba,Eu)Mg2Al16O27, blue phosphor for trichromatic fluorescent lamps (Ce,Tb)MgAl11O19, green phosphor for trichromatic fluorescent lamps (Y,Eu)2O3, red phosphor for trichromatic fluorescent lamps (Sr,Eu,Ba,Ca)5(PO4)3Cl, blue phosphor for trichromatic fluorescent lamps (La,Ce,Tb)PO4, green phosphor for trichromatic fluorescent lamps And dopants added to ZnS, what is the doping process; is it just adding a minute amount of what Cu compound and mechanically mixing or something more elaborated? Miguel

Hello What compound would glow when exposed to infrared light? It is used applied as paint on a piece of cardboard to test the illumination from remote controls and infrared beams. Read it is some phosphor compound, but unsure if it is plain white phosphor with something else or not. It is shown here: http://img.alibaba.com/photo/10846815/Infrared__IR__Laser_Test_Card__Anti_stoke_.jpg Thanks, Miguel

Hi. Mixing two cells in series -one charged, the other not- is not a good idea as the charged one may overheat, or dry out. You would be exceeding its charging recommendation time. Two cells in parallel is not a good idea either, as by any unbalance reason current may pass mostly into one and poorly into the other. Cells in parallel is fine for lead-acid and Lithium-ion, but not for Nickels. So what is the charging current measured? I believe for AAA cells should be under 20mA and the red LED can work just fine. If the charger is really limiting the current, should work equally well with only one cell on the bay. Measure the current! It is the case of a shorted cell put to charge; it should not damage the charger nor affect its companion cell, then a resistor or a short could work equally well. Miguel

Hi. Depends on what the batteries chemistry requiere for charging; constant current or constant voltage, and which type of charger it is. No way a common capacitor can be inserted in place of the missing cell. Measure the current on a bay with 2 cells under charge and place a resistor to obtain the same current in place of the missing cell bay. A light bulb could be used too, and if the charge current is under 20mA; a red led could take its place too, as it would provide ~1.5V drop and handle the current. Miguel

Oooops. Sorry, goofed distracted following the refrigerator word stuck to the request. Get a split airconditioner. Will work for distant rooms as the insulated hoses can be of a good lenght; both have already built-in fans for circulation, and provides both heating and cooling areas. Visit your AC shop for an unwanted one going to the dumpster. Miguel

Hi. A working old refrigerator with interior damages should be available free at any refrigerator repair shop. A good way to use it would be inserting the refrigerator in a polyestirene wall dividing areas from your reptiles and your plants, the heat releasing condenser part to keep warmth in one side; and -door removed- the cooling side for the plants. If its thermostat control is working, you are prerfectly set by just adding a fan to the evaporator cooling side... and defrosting periodically. Miguel

This place needs no Mentos... http://www.scienceexperiment.co.uk/experiments/ Enjoy.

Hello 5614 ..."We're talking about making our own charger here"... -->Yes, apply 4.100v to each cell. If you want to make it 'not-home-style'; pick the chip of choice: http://search.national.com/iphrase/query?query=liion+charger&render=1&categories=Product+Folders ..."I don't think it matters whether it is 4V or 4.2V"... --> Yes, it matters. The voltage has to be the one matching the cell chemistry; If too high; degradation takes place; if too low, will not reach full charge. That is why circuitry inside battery packs are so precise, microcontrolled. ..."I would assume they all have equal resistances"... -->Wrong assumption. Miguel