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Half life of 7.7 x 1015 years. That's roughly 10,000 times longer than forever. (e: re the radioactive cadmium bit on the last page)
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Jul 30, 2014 07:58
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Digiwizzard posted:Can you explain? 113Cd has a half‐life of 7.7×1015 years. For comparison, 238U, used in orange Fiestaware, has a half‐life In fact, 113Cd is closer in half‐life to 209Bi (1.9×1019 yr), which was thought to be stable for the longest time. e: A back‐of‐the‐envelope calculation says that organic carbon is ten times as radioactive thanks to 14C, and carbon is certainly not generally considered “a radioactive element” on that account. Platystemon has a new favorite as of 08:42 on Jul 30, 2014 |
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Jul 30, 2014 08:02
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Digiwizzard posted:Can you explain? It can't be a radioactive element if it has any stable isotopes. I'm not being pedantic here; words have meanings. Without knowing the isotope mixture of a given sample of cadmium, you can't say if it's radioactive or not. But I'm a nuclear engineering student; that article is for chemical engineers and they may have much less stringent definitions for the "radioactive" label.
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Jul 30, 2014 08:03
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Platystemon posted:113Cd has a half‐life of 7.7×1015 years. For comparison, 238U, used in orange Fiestaware, has a half‐life more than one million times shorter Wait, it decays before it's formed? That's a major breakthrough!
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Jul 30, 2014 08:31
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Platystemon posted:113Cd has a half‐life of 7.7×1015 years. For comparison, 238U, used in orange Fiestaware, has a half‐life more than one million times shorter (4.5×109 yr)—and238U is itself not all that radioactive. It’s actually used for radiation shielding against the really dangerous stuff. Ah, thanks. That's fascinating. I knew it had an absurdly long half life but I always thought it was still (very weakly) radioactive because it undergoes decay, but this is why Nuclear Physics isn't my area of expertise.
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Jul 30, 2014 08:36
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I decided to go ahead and look up some numbers. Natural potassium is composed of 0.012% potassium-40, a radioisotope with a half-life of 1.248 billion years. In spite of this tiny amount, this relatively short (on a cosmological scale) half-life gives natural potassium a specific activity of 31.72 Bq/g. Natural cadmium contains 12% cadmium-113, as mentioned in that article. It is also a radioisotope but has a much longer half-life of 7.7*1015 years. I tried to look up natural cadmium's specific activity and couldn't find it; it was so vanishingly small that no one cared enough to list in anywhere. So I ran the numbers myself and came up with 0.00186 Bq/g specific activity in natural cadmium. Are you still going to call cadmium radioactive as a rule? Do you consider bananas to be radioactive too? Keiya posted:Wait, it decays before it's formed? That's a major breakthrough! Huh? 7.7*1015 / 1.0*106 is 7.7*109 which is still longer than U-238's half life of 4.5*109. BattleMaster has a new favorite as of 08:47 on Jul 30, 2014 |
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Jul 30, 2014 08:43
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BattleMaster posted:I decided to go ahead and look up some numbers. No, because only a partial amount of the element decays like you said. Not sure why you're getting up in arms about this.
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Jul 30, 2014 08:47
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Digiwizzard posted:No, because only a partial amount of the element decays like you said. Not sure why you're getting up in arms about this. Because someone was wrong ON THE INTERNET. Edit: Also it took longer for me to write my post than it did for you to reply to anything so I probably came off as more snarky than the situation warranted BattleMaster has a new favorite as of 08:50 on Jul 30, 2014 |
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Jul 30, 2014 08:48
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 my nuclear credibility...
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Jul 30, 2014 08:50
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BattleMaster posted:Huh? I was admittedly a little sloppy with the language. “Times less than” is ill‐defined. “Product A costs five times more than product B” makes perfect sense, but “product B costs five times less than product A” is confusing.
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Jul 30, 2014 08:56
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BattleMaster posted:Are you still going to call cadmium radioactive as a rule? Do you consider bananas to be radioactive too? I was told that eating 1000 bananas increased your risk of death by one micromort.
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Jul 30, 2014 09:10
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moller posted:I was told that eating 1000 bananas increased your risk of death by one micromort. 
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Jul 30, 2014 09:30
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Rev. Bleech_ posted:Aaah, memories. Floppies with a copy of qcrack.exe were all that was necessary for Nerd Stardom back in 1996 It never failed that the only guy around with that disk (not just qcrack.exe, but any sort of dubious software back then) was the most obnoxious piece of poo poo that nobody could stand, who would watch you like a hawk while you were using it to make sure you didn't try to copy it. You know, so if anyone wanted to use the software, they had to invite him over.
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Jul 30, 2014 12:42
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Digiwizzard posted:Can you explain? Basically what others said. Once you reach a certain cutoff limit for half-lives, an element is considered for all intents and purposes stable. Potassium is far more radioactive than cadmium, but we would laugh if they told us to do a rad inventory on the potassium stocks in our lab.
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Jul 30, 2014 19:25
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GOTTA STAY FAI posted:It never failed that the only guy around with that disk (not just qcrack.exe, but any sort of dubious software back then) was the most obnoxious piece of poo poo that nobody could stand, who would watch you like a hawk while you were using it to make sure you didn't try to copy it. You know, so if anyone wanted to use the software, they had to invite him over. Man that's why I used Usenet.
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Jul 31, 2014 16:40
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mints posted:Man that's why I used Usenet.
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Jul 31, 2014 16:56
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Oh man, you're right. I think I just told people in class what newsgroup to browse to find it. It wasn't until college that I became the annoying guy that came around, and that was more to share the weekly Essential Mix.
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Jul 31, 2014 18:53
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I remember around 1999, going to a friend of a friend's house and seeing serious online piracy for the first time. This dude had two or three CRT monitors hooked up and a whole wall of media shelves filled with burned VCDs of anime and pirated movies. He got all his stuff from newsgroups and IRC -- he totally cultivated this elitist attitude of secret knowledge -- and it blew my mind as someone who had only dabbled with things like Napster for a few lovely MP3s. I eventually figured out Newsgroups as well (never did grok IRC for file sharing), but to this day IRC and Newsgroups are still to me what my wife calls "some impressively computery looking stuff". As in, from across the room it looks like you're doing some serious Matrix hacker crap. At the time I thought this dude was a wizard or something.  Now I wonder what he did with all those lovely 700MB-quality VCDs about 4 years later when they became worthless. Another fun newsgroup thing. Comedian Kumail Nanjiani has a new podcast called "The X-Files Files" where he's rewatching the whole series, and he's been going back into the alt.tv.xfiles archives from the time and talking about the fan comments from when the episodes aired. The recent show about the episode "E.B.E." had Dean Haglund of the Lone Gunmen on there, and he had some great anecdotes about the relationship between the show's writers and the newsgroup, and how the few dozen fans posting on there changed the whole show. Imagined has a new favorite as of 19:22 on Jul 31, 2014 |
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Jul 31, 2014 19:15
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Imagined posted:Another fun newsgroup thing. Comedian Kumail Nanjiani has a new podcast called "The X-Files Files" where he's rewatching the whole series, and he's been going back into the alt.tv.xfiles archives from the time and talking about the fan comments from when the episodes aired. The recent show about the episode "E.B.E." had Dean Haglund of the Lone Gunmen on there, and he had some great anecdotes about the relationship between the show's writers and the newsgroup, and how the few dozen fans posting on there changed the whole show. Had to go back a few pages in the Trek thread in TVIV, but someone posted a link to a newsgroup discussion about the first episode of ST:TNG. Nerds never fuckin' change.
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Jul 31, 2014 20:03
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Now I want to dig through old discussions about TNG. Or see if anyone made any posts about summer blockbuster movies back in the mid 80s.
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Jul 31, 2014 21:27
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mints posted:Now I want to dig through old discussions about TNG. Or see if anyone made any posts about summer blockbuster movies back in the mid 80s. 
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Jul 31, 2014 21:29
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Babylon 5 also had a very active group where JMS responded to comments people were making in regards to the show and revealing behind the scenes snippets and thoughts into how he made the show. Lurker's guide Has several of these quotes neatly summed up each episode. And this turned up... https://www.youtube.com/watch?v=PBDKEn-TeQg Somewhere in Robert X Cringely's "Nerds" series there's a part on the early days of webcam girls. However that series is fascinating to look through as it's at the height of the . com boom and he interviews so many startups and firms who's quick buck ideas drowned.
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Aug 1, 2014 00:51
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Imagined posted:never did grok IRC for file sharing It was the best of times it was the blurst of times. IRC file sharing was pretty terrible, but the way to get  before bittorrent was invented. Most ISP didn't provide the alt.binaries hierarchy on usenet, so IRC was the place to go for the latest .mpg of the Simpsons or terrible terrible .rm enocoded anime.There was this huge script for mIRC called Polaris that worked as a fserve or XDCC serve. People with fast connections ran bots with the Polaris scripts that were fileservers. You would join a channel like #futurama-mpeg or #m4ng0st333n_w4r3z and stick around for a bit. A bot would tell you the rules, and if you didn't follow them, got kickbanned. Some channels allowed you to say !list, which would make all compliant bots send you a list of files in a private message. You would then send request to the bot, which placed you in line a file. Then you just had to wait for everyone else to get their files or get dropped from a huge netsplit or some other random glitch. If you were lucky, eventually the bot would set up a binary transfer and send over the requested file. Large files were often divided into chunks of 25M each in a split .rar archive. Other bots would run adds for ftp servers. These were also really annoying. If you got lucky or knew someone you could be let into private IRC channels or get logins for ftp servers with no lines. The few people on fast connections were expected to serve if they wanted to get in on the good stuff. I had a feeling there were a lot of these servers on university Unix accounts. e: 
axolotl farmer has a new favorite as of 19:16 on Aug 1, 2014 |
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Aug 1, 2014 19:12
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I knew one of the guys in that screenshot
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Aug 1, 2014 19:24
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I sort of ran one of those channels for 10 years. Had 800 people at it's peak. Looking back, probably a very bad idea.
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Aug 1, 2014 19:25
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I kinda miss those days a bit. fserves, XDCCs, rewards of voice or half-op status if you really contributed. I remember SysReset and UPP being somewhat popular scripts for mIRC also.
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Aug 1, 2014 19:27
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One surprisingly easy and smooth way of getting warez back in the day was to simply look at usenet, in regular text posts, merely using Outlook Express and my ISP's usenet access. Some people would make a post like "New FTP up, ftp.warez.com:21, user/pass so and so, rules so and so", and one could just connect and start downloading; some requiring a small amount of uploading (maybe a 10:1 download/upload ratio).
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Aug 1, 2014 20:17
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I was too poor to afford a modem so it was all floppies from my friend's Aleph Null has a new favorite as of 20:42 on Aug 1, 2014 |
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Aug 1, 2014 20:40
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Back in high school (late 90s) I was that guy and had a Mac. Which meant piracy was a little different. Or maybe it wasn't, but the go to for that stuff was Hotline and then later Carracho. http://en.wikipedia.org/wiki/Hotline_Communications P2P before P2P was a thing. Software hasn't been updated since 2003, although I'm sure there are still servers out there somewhere.
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Aug 1, 2014 20:45
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G-code, otherwise known as a VCR Plus+, VideoPlus+ and ShowView http://en.wikipedia.org/wiki/Video_recorder_scheduling_code Back in the 90s when VCRs were too complex for mere mortals to program, someone came up with the bright idea of publishing codes in the TV Guides that you'd enter into your VCR and they'd correspond to the time/channel/duration for the program. Worked pretty well as I recall. Made obsolete by Tivo and Bittorrent. The algorithm for decoding the 4-8 digit codes was remarkably complex. For some reason the makers of G-code thought it best to encrypt the codes, I guess so they could sell the information to TV Guide. http://www.straightdope.com/columns/read/782/how-do-the-tv-program-codes-for-vcr-plus-work
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Aug 4, 2014 08:38
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G-Code was so hit and miss as sports or the schedule in general would change unexpectedly, (In Aust, Channel 9 was infamous with this), so you end up recording something else entirely. It was more efficient to just press record when the program was in. On that note there also was the V-Chip, which screened out content set above a particular rating encouraged by misguided reports we were raising a generation of violence addicted kids. Every TV from Jan 2000 had to have it installed, but the result was that barely any parents actually used it or were aware of it but didn't see the point in setting it up as it would otherwise disrupt regular viewing. Also at the time there was almost no real need to buy a new TV so the market was a very very slow adopter. And even today content locks are still rarely used as they interrupt with regular viewing. BogDew has a new favorite as of 10:23 on Aug 4, 2014 |
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Aug 4, 2014 10:17
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WebDog posted:G-Code was so hit and miss as sports or the schedule in general would change unexpectedly, (In Aust, Channel 9 was infamous with this), so you end up recording something else entirely. It was more efficient to just press record when the program was in.
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Aug 4, 2014 15:18
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axolotl farmer posted:Large files were often divided into chunks of 25M each in a split .rar archive. And even today some places still annoyingly do this, especially if you're downloaded something immediately after it airs. Not quite that small but it's still common to see hour long shows broken into 20 or so .rars. How far piracy has come really is amazing, you no longer have to worry about downloading what you think is the Simpsons and getting hosed up porn or an exotic second world virus. Well not as much as in the kazaa and napster days.
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Aug 4, 2014 15:34
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thethirdman posted:See also uranium glass. GWBBQ has a new favorite as of 16:27 on Aug 4, 2014 |
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Aug 4, 2014 16:24
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gleep gloop posted:And even today some places still annoyingly do this, especially if you're downloaded something immediately after it airs. Not quite that small but it's still common to see hour long shows broken into 20 or so .rars. How far piracy has come really is amazing, you no longer have to worry about downloading what you think is the Simpsons and getting hosed up porn or an exotic second world virus. Well not as much as in the kazaa and napster days. They usually came from newsgroups that way.
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Aug 5, 2014 05:10
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GWBBQ posted:I'm the guy who goes through the glassware section at thrift stores with a blacklight pen, uranium glass glows bright green under UV light. They're usually a dollar or two and they either make neat display pieces with a few UV LEDs or can be flipped for $10 or so on eBay. Well I know what I'm doing this Saturday.
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Aug 5, 2014 05:22
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The first 'smart phone' IBM Simon  http://en.wikipedia.org/wiki/IBM_Simon quote:The IBM Simon Personal Communicator was a handheld, touchscreen cellular phone and PDA designed and engineered by International Business Machines Corp. (IBM) and assembled under contract by Mitsubishi Electric Corp. BellSouth Cellular Corp. distributed the Simon Personal Communicator in the United States between August 1994 and February 1995, selling 50,000 units. The Simon Personal Communicator was the first cellular phone to include telephone and PDA features in one device. I kind of want one for laughs
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Aug 18, 2014 08:50
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Humphreys posted:I kind of want one for laughs http://www.ebay.com/itm/IBM-Simon-First-Smart-Phone-Works-/400758781989 Knock yourself out.
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Aug 18, 2014 10:27
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Wanamingo posted:http://www.ebay.com/itm/IBM-Simon-First-Smart-Phone-Works-/400758781989
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Aug 18, 2014 13:54
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I have an obsolete and failed technology to post that I'm very happy to obtain! Dual TG 27 four track tape recorder from 1968. It doesn't work, but I can fix it, and it was only $25 with a reel of tape. I'm going to track/print so much stuff on this old bastard.
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Aug 20, 2014 01:31
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