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Disney to Begin Renting 'Self-Destructing' DVDs.

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interesting... i've already thought of several ways to circumvent the problem (must be the troubleshooter in me).

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While we are working hard to get rid of foam/plastic food containers worldwide, here comes another 'brillant' environmental-unfriendly idea to ruin it :angry:

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While we are working hard to get rid of foam/plastic food containers worldwide, here comes another 'brillant' environmental-unfriendly idea to ruin it  :angry:

If you don't aprove, then don't purchase them.

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From what Ive read about these discs, is that the coating starts to degrade once exposed to air, so after a predicable period of time the disc is no longer read able. You could 'cheat' a little perhaps, by storeing the discs in a vaccum or other oxygen free container...

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While we are working hard to get rid of foam/plastic food containers worldwide, here comes another 'brillant' environmental-unfriendly idea to ruin it  :angry:

That's exactly what I thought too. More plastic junk to litter the ground. :(

If you don't aprove, then don't purchase them.

Now how does that solve the problem? If other people destroy the environment, that affects me too.

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You could 'cheat' a little perhaps, by storeing the discs in a vaccum or other oxygen free container...
Perhaps some acid or other chemical could eat it away? Pehaps the cd scratch removing kits could polish the stuff off?

I find it kind of weird that it's cheaper to make these throw away discs rather than process returned discs at blockbuster.

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I find it kind of weird that it's cheaper to make these throw away discs rather than process returned discs at blockbuster.

I don't think that's the point of the exercise.

IMO the point is to hugely increase the number of retail outlets for DVD movies. Imagine how many small retailers (who don't want the extra hassle of becoming a video rental operator in addition to their current business) would be quite happy to stock the top 10 or 20 movies in the form of a throw-away disk?

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I think it's an ingenious and great idea. Many retailers would carry these, many people would rent them and enjoy them, and many people would spend late evenings trying to figure out ingenious and great ways to prevent the self-destruction :)

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This is the dumbest, stupidest, most idiotic idea in quite some time. The previous winner was the idea of using the location tracking ability of cell phones to call somebody up when they happened to pass near a business, and give them a prerecorded telemarketing call from that business. For example, you drive along and pass by Joe's Pizza. Bingo, your cell phone rings and tells you about their specials. Thankfully, that idea never saw the light of day due to the huge potential for driver distraction(and annoyance). Hopefully, the environmentalists will stop this one cold(along with disposable cell phones, cameras, etc.). While we're at it, we should phase out disposable batteries. What is so hard about putting a battery in a charger when it's dead? Children's toys are the worst offenders here with their steady diet of C and D cells but adult toys like digital cameras can eat batteries up pretty fast as well.

Another thing-renting DVDs costs what-$3 to $5? For a few dollars more in many cases you can just buy the movie outright, especially if the movie industry gets smart and lowers prices enough to take the profit of piracy. So what's the point of renting? And what's the point of this whole retarded idea? Another disposable piece of garbage to increase the cash flow of a few businesses perhaps? Start selling real quality products that people need instead of gimmicky garbage if you want to increase your business instead. I for one am sick to death of planned obsolescence and the disposable mentality.

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It will be interesting to see how long before college students figure out a relatively easy way of preventing the oxidation.

Off the top of my head, I'd think that just spraying the surface with a clear enamel or lacquer immediately after intial exposure to air might be be sufficient (provided that the coating doesn't fubar the optical properties); the reaction that degrades the media probably relies on constant exposure to oxygen.

Even if it only requires initial exposure, then I could see students attempting the following experiment:

(I am not an expert or anything, so I'm not recommending that anybody actually try this.)

1. Obtain relatively large ice chest.

2. Pour a quantity of liquid nitrogen into the chest and wait a bit; the resulting nitrogen gas will settle to the bottom of the chest, displacing the air and associated oxygen.

3. Using appropriately insulated gloves and eye protection, open package in nitrogen atmosphere, remove disk and seal with a clear coating. Wait for coating to dry.

I have no idea if this would work, and it is a bit dangerous (LN2 is very cold, so the resulting nitrogen atmosphere will be very cold as well).

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I wouldnt use nitrogen, as it is volitile and can react violent... (ever notice explosive often have "nitro" in the names?) I would use an inert gas like argon. also becuase liquid nitrogen is extreamly cold, its difficult to handle (expensive) and safety would be a major concern around it.

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Hopefully, the environmentalists will stop this one cold(along with disposable cell phones, cameras, etc.).  While we're at it, we should phase out disposable batteries.  What is so hard about putting a battery in a charger when it's dead?  Children's toys are the worst offenders here with their steady diet of C and D cells but adult toys like digital cameras can eat batteries up pretty fast as well.

Disposable cameras? The single use cameras are reused/recyled after the film is processed, unless the consumer decides to throw out the camera.

While there are many good uses for rechargeable batteries, applications that do not require battery changes every 1-3 months would probably do better with primary cells. Applications that require battery changes only annually or less frequently such as smoke detectors, remote controls, clocks, some flashlights and cameras, etc., or any device requiring reliable power should utilize primary cells. And of course many miniature primary cells, such as watch and pager batteries have no secondary replacements.

It is an inconvenience for a typical consumer to put a battery in a charger when it is dead, especially if they have a dozen devices in unknown states of charge. Perhaps secondary batteries would be more accepted if they were more reliable, less expensive, and did not suffer from significant self-discharge. Unfortunately each of the battery chemistries has some disadvantages.

BTW, I am a proponent of rechargeable cells. I started using NiCd cells 35 years ago and started designing chargers 26 years ago, when high-speed chargers were few and primitive.

Bettis

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I wouldnt use nitrogen, as it is volitile and can react violent... (ever notice explosive often have "nitro" in the names?) I would use an inert gas like argon. also becuase liquid nitrogen is extreamly cold, its difficult to handle (expensive) and safety would be a major concern around it.

The vapor pressure of nitrogen caused by the phase change from liquid to gas can cause "explosive" effects. However, nitrogen is relatively inert under the conditions of use. (Nitro compounds are a differnent amtter.) The main hazards of using liquid nitrogen for unskilled or improperly equipped personnel are frostbite and hypoxia. I have no idea if universities have chemical hygiene officers today, but suspect that students are as foolish as ever.

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I wouldnt use nitrogen, as it is volitile and can react violent... (ever notice explosive often have "nitro" in the names?) I would use an inert gas like argon. also becuase liquid nitrogen is extreamly cold, its difficult to handle (expensive) and safety would be a major concern around it.

Yes, argon or another noble gas would be a better environment. However, when I was an undergrad, there were TONS of LN2 dewars readily available (LN2 is relatively inexpensive) while the others were much harder to access. LN2 and even N2 is not all that reactive at the low temperatures involved in this thought experiment (Still, I'd advise against using a coating with toluene as a solvent even at these low temps, as you might end up with an unwanted byproduct - [TNT =trinitrotoluene]).

Argon would be the preferred gas; it is heavier than air at STP; I suppose you could invert my idea and use He instead (i.e. an inverted aquarium workspace).

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(Still, I'd advise against using a coating with toluene as a solvent even at these low temps, as you might end up with an unwanted byproduct - [TNT =trinitrotoluene]).

I don't think so. The nitrogen will not spontaneously oxidize, nor will electrophilic substitution occur. :) TNT is synthesized by repeated nitration of toluene under very acidic conditions (e.g., nitric acid/sulfuric acid) and at high temperatures.

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LOST6200:

I suspected that high temperatures would be required, but how high I couldn't recall anymore; I do remember that commercial ammonia synthesis uses a ton (scientific term) of heat. I was just worried that some wank would drop his smoke in a mixture of concentrated N and toluene and end up with an unexpectedly strong reaction (more than expected from simple ignition of toluene).

My knowledge of chemistry has severly degraded over the decades...thanks for the reassurance that some student won't blow him/herself up trying to tinker with these silly disks. :)

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You guys are making it too hard.. just submerse your whole DVD player and DVD collection in a non cunductive liquid made for this stuff. 3M makes some that I know of.(dont recall the name) :D

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Applications that require battery changes only annually or less frequently such as smoke detectors, remote controls, clocks, some flashlights and cameras, etc., or any device requiring reliable power should utilize primary cells.  And of course many miniature primary cells, such as watch and pager batteries have no secondary replacements.

Here I agree with you for the simple reason that all secondary cells except lithium-ion self-discharge within a period of months, and lithium-ion is still too expensive(with too finicky recharging requirements) for general use. However, throwing away a spent AA from a clock or a 364 cell from a watch every year or two is not the greatest contributor to the landfill problem. Rather, it is the high-drain, frequent use applications using C or D cells which are the greatest problem, and I think childrens' toys are the biggest culprit here. It is these applications that are ripe for rechargeables. NiMH has increased in capacity to the point that in many cases the cells last longer than comparable alkaline cells, so lack of capacity is no longer a valid excuse. Cost certainly isn't as rechargeables save you money, lots of money, over the long run. Self discharge isn't an issue either when in most cases the children using the toys drain the cells within a matter of days anyway. Of course, there is no interest on the part of battery manufacturers to sell rechargeables in large numbers for such applications since it would cut into their cash cow. Therefore, action needs to be taken in the form of laws phasing out these larger primary cells while keeping the smaller ones for the low drain applications where they are needed. As long as these larger primary cells exist, those consumers who can't be bothered sticking a dead battery in a charger will continue to buy them. Adopting rechargeables for low-drain applications can come later when battery manufacturers are able to make low-cost secondary cells with low self-discharge. For now, I'll continue to use AA alkalines in wall clocks but look forward to the day when a rechargeable will work just as well. And acceptance of secondary cells can be increased by having chargers that give a reliable indication of the state of charge of a cell along with an estimated recharge time, so that any unknown cell can be tested just by popping it in the charging and looking at a readout.

I've also been using rechargeables for quite some time, and have designed and built a few chargers myself. Besides saving money and landfill, it's an interesting little side hobby. :)

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jtr, you're such a tree hugger  :P

I'll take that as a compliment. Seriously, though, I see economic value in preserving our environment for the simple reason if we destroy it now, future generations are screwed. Just look how much cleaning up the mess from irresponsible companies in the past is costing us now. I'll even admit I'm not much of a nature freak or outdoor person. In fact, I'll probably never visit any of the wild places I advocate preserving. Nevertheless, there is a value in preserving them. If we continue to develop and remove trees the CO2 problem will only get worse. The resulting climate change will wreak havoc with our economies, and perhaps threaten our very existence. So besides trying to end the landfill problem and switching to zero emission means of generating power(both for vehicles and powerplants), I'm also strongly against suburban sprawl as it represents the worst possible use of land. A suburban house on a half acre probably requires destroying ten acres when you count the land for roads and businesses to service that house. Cities make much more efficient use of land, and have a high enough population density to support more environmentally friendly means of transport than the automobile.

OK, I think I've already took this thread far enough off-topic. ;)

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I wonder when the software manufacturers will begin to use this technology. I bet that MS, et al. would be happy to see installation CDs self destruct after use. :)

JTR:

Yeah, it is a great hobby until one has a little accident. I'll never forget the 1.2A sub-C NiCd that exploded right in front of me back in '78. The top literally bounced off of the ceiling. I suppose the vent was bad. (Of course thaqt's what happens at 2.5C when Vref to the op amp amp is not stable due to HF parasitic oscillations.)

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I was attempting to recharge a 1/2AA lithium cell once after having had some previous success and the same thing happened to me. In fact, it exploded right in my hand. The thing sounded like a large firecracker. Most of the cell's innards ended up as a cloud of white smoke and some black stuff was on the ceiling. I couldn't see anything for a while and at first thought I was blind. I quickly learned not to attempt to recharge lithium cells again. Fortunately, I still have all my fingers. Outside of a slight burn on one finger and a little cut on another I really suffered no ill effects from the incident. I was very, very lucky.

I've had similar problems with parasitic oscillations on op-amps although none with as dramatic an effect as you had. I find sometimes a small capacitor(~1000 pF) between the inverting input and output works wonders where all else fails. This is using the ubiquitous 324 opamp or it's derivatives. Some of the better chips may not have this problem.

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