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The Chemistry Of Light Bulbs—And Why CFL’s Are Overrated
Science 2.0 ^ | Mar 26 2011 | Enrico Uva

Posted on 03/30/2011 7:35:54 PM PDT by neverdem

click here to read article


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1 posted on 03/30/2011 7:35:58 PM PDT by neverdem
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To: neverdem

All I know are these new light bulbs suck. I have difficulty reading under them.


2 posted on 03/30/2011 7:39:31 PM PDT by mimaw
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To: mimaw

And we have far too much sex on the television. I keep falling off.


3 posted on 03/30/2011 7:48:10 PM PDT by dangus
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To: mimaw

Seriously, if the light bulbs suck, you probably have them screwed in reverse. Screw them in the opposite direction, and they will emit, instead of sucking. No wonder you have difficulty reading.


4 posted on 03/30/2011 7:49:21 PM PDT by dangus
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To: mimaw
"All I know are these new light bulbs suck. I have difficulty reading under them."

Then you're not buying the ones with the appropriate spectral output. The article is pretty simplistic in its description of CFL's. There are several varieties with different "color temperatures". The normal CFL's have more blue emission, but there are "warm white" versions that duplicate incandescent spectra more closely.

5 posted on 03/30/2011 7:49:32 PM PDT by Wonder Warthog
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To: mimaw

If you have your light-bulb installed to emit, you have a Light Emitting Diode, or LED. If you have your light-bulb installed to suck, you probably have LSD.


6 posted on 03/30/2011 7:50:48 PM PDT by dangus
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To: mimaw
If each household breaks 3 bulbs per year either by accident or indirectly by sending them to a landfill...

What if, say, each of 100,000 households breaks about a dozen CFLs all within a minutes of each other by sending them to a wasteland, such as northeast coastal Japan?

7 posted on 03/30/2011 7:54:49 PM PDT by C210N (0bama, Making the US safe for Global Marxism)
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To: neverdem
We should not be bringing more mercury into our homes.

This is an environmental disaster in the making,

8 posted on 03/30/2011 7:57:41 PM PDT by FatherofFive (Islam is evil and must be eradicated)
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To: neverdem
Although there are still technical challenges ahead, LED lights will probably replace CFC's.

I sure hope so, I have quite a bit of money riding on it....
9 posted on 03/30/2011 8:03:30 PM PDT by WackySam (To argue with a man who has renounced his reason is like giving medicine to the dead.)
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To: FatherofFive

Remember asbestos? They put it in everything when I was a child. I remember being told in school have safe it was because it was permeated with asbestos - the floors, the ceilings.

Just watch. In 20 or so years all of a sudden it’s going to become a huge environmental emergency (all that Hg) and the scam artists that live off the government will suddenly start up all these “Toxic metal removal” companies. And get money from the public purse to do it.

Al Gore’s next scam.


10 posted on 03/30/2011 8:05:20 PM PDT by I still care (I miss my friends, bagels, and the NYC skyline - but not the taxes. I love the South.)
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To: neverdem

They crap out quickly in my part of the world (high and cold), and the light from them is dim through their short lives. LEDs are better for here but mucho expensive.


11 posted on 03/30/2011 8:09:35 PM PDT by familyop ("Wanna cigarette? You're never too young to start." --Deacon, "Waterworld")
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To: FatherofFive
Yup. Just look up how to handle CFLs on the EPA website. Lol.

http://www.epa.gov/hg/spills/

12 posted on 03/30/2011 8:13:16 PM PDT by dhs12345
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To: I still care
I remember being told in school have safe it was because it was permeated with asbestos - the floors, the ceilings

Each lab station in my high school science classroom had a plastic bottle full of mercury. I don't remember what science projects the mercury was for, but we enjoyed rolling it around in our palms. Somehow we've all reached our late 40s apparently unscathed.

13 posted on 03/30/2011 8:27:54 PM PDT by Minn
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To: WackySam

My nephew is working on LEDs at Phillips Luminesce after 20+ years with HP and it’s spin offs developing things like hand held barcode scanners to the camera modules for cell phones. Phillips has experimental LED street lighting in a couple of towns in France that I know of...


14 posted on 03/30/2011 8:29:37 PM PDT by tubebender (Now hiring Tag Line writers. Full time low pay)
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To: Minn

Pure mercury is actually pretty safe because the body doesn’t absorb it well (but it’s nasty if ingested). The real danger comes from mercury compounds that can be absorbed through the skin or lungs.


15 posted on 03/30/2011 8:31:44 PM PDT by Squawk 8888 (Will work for chocolate)
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To: Wonder Warthog
None of the CFL's have a continuous spectrum like an incandescent. The color values of an object depend on the integrated reflectivity over the spectrum, so there will inevitably be differences in color appearance among objects which appear the same color in natural light, which of course is incandescent. There are "holes" in the CFL spectra, and these will match up differently with the reflectivity spectra of various objects.


16 posted on 03/30/2011 8:42:02 PM PDT by dr_lew
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To: neverdem
These first caught Edison’s attention, but he had never time for further investigations; otherwise, as David Bodanis suggests, Edison may have discovered electrons before J.J. Thomson.

Edison could be said to be the grandfather of electronics. During his investigation of aging effects in his incandescent lamps, he added a small metal plate adjacent to the filament (but not touching it), and brought a connection to it out the side of the bulb.

[Edison was the ideal guy to do this, because in the 1880's nobody was better at building evacuated glass bulbs with things like filaments and plates and bringing their connections out through gas-tight seals in the glass.]

Anyway, he noticed that you could get an electrical current to flow from the plate to the filament through the vacuum, provided you connected the + end of a battery to the plate and the - end to one of the filament leads. I don't think that anybody else had thought, at that stage, that such a thing could happen.

Oh, and one other thing about this phenomenon (that came to be called the "Edison Effect"): current would not flow in the other direction. You could hook up the battery - to the plate and its + to the filament, and nothing would happen.

Bear in mind that Edison's electrical system was exclusively DC--direct current. He had no use for a device that admitted current flow in one direction but not the other, because any element in his system would always be passing current in one direction only.

So, after patenting a device that made trivial use of his gadget, he set it aside. A few physicists here and there got copies of the gadget and investigated it, and then they too set it aside.

Meanwhile, radio was invented by the likes of Tesla, Marconi, and Preece.

One of the early problems with radio transmission was that the first receivers were incredibly insensitive. An example was the "coherer" of Edouard Branley, an insulating tube filled with fine iron filings, which could be made to conduct when furnished with a pulse of radio frequency energy from the aerial. As a result of the deafness of the available receivers, transmitters in the first decade of the 20th centry were being built to gargantuan proportions in order to get enough power into the distant receivers for them to operate. In effect, the receivers were directly transmitter-powered.

So the search was on for a better detector, the heart of the receiver that could turn radio waves from the aerial into currents that could operate things such as telegraph sounders.

Around 1904, John Ambrose Fleming, an English physicist, pulled a dusty Edison apparatus out of a drawer. He reasoned that a device that could pass current in only one direction--that is, it could rectify--might the the ticket to a better detector. In a short time, he hooked it up in a receiver and got an astounding improvement in sensitivity.

Although this was not the only innovation in early radio receivers (the Galena crystal and cat's whisker were another), it set radio technology on a rapid growth curve.

About four years later, a young Stanford PhD on the west coast by the name of Lee DeForest reprised Edison's experiments of two decades previous, in order to better understand the behaviour of what was now being called the "Fleming Valve." This time, he inserted a third element between filament and plate which he called a "grid." He discovered that varying potentials on the grid controlled the flow of current from the plate to the filament, and that he could control a given amount of current with a small amount of voltage. Thus, his gizmo was the first electronic device to exhibit gain. And thus not just radio, but electronics itself was finally born.

Had Edison done his work just ten years later, and had he been developing AC systems, he might have been the father and not just the grandfather of electronics. As it was, DeForest was the father and Fleming, you might say, was the midwife.

Postscript: In 1897, amidst the early development of radio, English physicist J. J. Thompson used an early version of the cathode ray tube to discern the nature of the effect that gave the tube its name. In doing so, came up with convincing evidence that the current through the vacuum was being carried by tiny, tiny particles which he called "electrons." Further experiment revealed the charge and mass of the electron, and established that it was a constituent of the atom--the first subatomic particle to be discovered. It was also shortly established that the electron was also the carrier of electric current through ordinary conductors as well.

One final discovery. According a convention in electrical research that was long established even in 1897, Thompson found that the charge on the electron was negative. Therefore, in the various electron devices here described, the "conventional current" was flowing in the device from plate to filament, but in actuality the negative electrons were flowing from filament to plate. A fact that confuses beginning EE students to this very day. ≤}B^)

17 posted on 03/30/2011 9:00:04 PM PDT by Erasmus (I love "The Raven," but then what do I know? I'm just a poetaster.)
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To: Erasmus

RE your post 17: Fascinating, thanks for the lesson!


18 posted on 03/30/2011 9:09:58 PM PDT by theymakemesick ( islam - inspired by Satan www.prophetofdoom.net)
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To: Erasmus

Thanks for the history.


19 posted on 03/30/2011 9:37:39 PM PDT by neverdem (Xin loi minh oi)
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To: neverdem
See my tag line.

I wonder if the young Tea Party hotshots in Congress are going to bring this up and relieve us of the curly light bulbs. I don't hear a peep from them about this.

I know they're handling some other things of importance like the budget and war and all that stuff....but how long would it take to slip in a little light bulb legislation?

I would even write it for them.

Leni

20 posted on 03/30/2011 9:48:00 PM PDT by MinuteGal (Obama....you'll have to pry my incandescent lightbulbs from my cold, dead fingers!)
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