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December 24[edit]

Happy Holidays![edit]

Just saying, as per Dr Dima, happy holidays to all from here in brown Australia. o<]:-) Julia Rossi (talk) 04:12, 24 December 2008 (UTC)[reply]

Hey, no ranting!! Happy Christmas to you JR from economically and climatically gloomy UK. Richard Avery (talk) 07:25, 24 December 2008 (UTC)[reply]

Happy holidays from the origin of the global economic crisis. Imagine Reason (talk) 13:46, 24 December 2008 (UTC)[reply]

Might as well join in....happy holidays to you all from the southern most tip of the darkest continent, and the most beautiful city in the world! And Julia, better luck in the cricket tomorrow! I sure hope McGrath is enjoying some humble pie with his Christmas lunch :P Zunaid 16:03, 25 December 2008 (UTC)[reply]

deleet! deleet! :-> Julia Rossi (talk) 00:00, 26 December 2008 (UTC)[reply]

Happy holidays from...Canada! So what's your question? ~A H 1^(TCU) 16:49, 25 December 2008 (UTC)[reply]

Happy holidays from (location undisclosed) too! I think this "Question" should go into the "Miscellaneous" RD. ♫Death gle an er 00:43, 27 December 2008 (UTC)[reply]

Test for fullerenes[edit]

How can I test for fullerenes? I remember a chemical experiment I did decades ago when the previously clear liquid very suddenly turned dark black with a shade of violet. I told my chemistry teacher and he repeated the experiment with the same result but could not tell me what it was. Now the vision haunts me that I was creating, well, "some nano stuff" in a cheap and easy way (very probably I wasn't). So how can I have peace by either knowing that it wasn't some precious nano stuff or, preferably, getting famous, rich and wealthy by creating nanos en mass and selling it? 95.112.140.196 (talk) 09:31, 24 December 2008 (UTC)[reply]

I don't know the answer to your question, but I'd just like to say that even if you do find a way to bulk-produce nanos, it's highly unlikely you'll be able to sell them, because they'll probably be extremely impure. AFAIK it's relatively to produce fullerenes, but getting the different kinds separated and tossing out the junk ones isn't something you could just do in your basement without putting a f*ckton of money into the necessary equipment. Yeah, I know you were (probably) kidding about the getting famous, rich and wealthy part, but I figured I'd debunk it anyway.

As for becoming famous, well, you might make the news if you poison or blow up half the block trying to find a cheap way to create fullerenes. ;) --Link ^(t•c•m) 11:30, 24 December 2008 (UTC)[reply]

Looking through the article you linked, getting rich is only within reach if your method would produce pure fullerenes. Since they do appear in nature (albeit in miniscule quantities) in soot and rocks, just making them isn't enough. Look though the list of properties and test your sample for those. That way you should be able to narrow it down if your test tube doesn't contain something like that. 76.97.245.5 (talk) 11:24, 24 December 2008 (UTC)[reply]

Unfortunately the properties stated are not good for testing. If I had the equipment, I could take IR, Raman and UV spectra but still was at loss on what these spectra should look like. What would be the way to distinguish nanos from ordinary soot? And on the pureness I was hoping that by a defined chemical process would lead to a more defined product than the random product generated by the plasma discharge of an electric arc. 95.112.140.196 (talk) 12:07, 24 December 2008 (UTC)[reply]

As to the experiment you did decades ago, I remember that one from high school. It's a clock reaction involving iodine compounds. You mix your reagents and there are two chemicals that would react but the presence of a third chemical inhibits this. However, that chemical reacts slowly with one of the others (or a fourth one in the mix) and is consumed over a few seconds (or up to about a minute, depending on the exact mixture). Once it's all gone, the other reaction happens and you get the dramatic color change. Ah, here we are: iodine clock reaction. No nano needed, nanoo nanoo. --Anonymous, 21:38 UTC, December 24, 2008.

material science[edit]

give examples of nano piezo electric crystals having electro catalytic properties —Preceding unsigned comment added by 202.88.239.150 (talk) 10:30, 24 December 2008 (UTC)[reply]

Sounds like you want us to do your homework for you. StuRat (talk) 15:14, 24 December 2008 (UTC)[reply]

OK then, we'll do it for you: give examples of nano piezo electric crystals having electro catalytic properties - the Wikipedia Reference desk answers all. ;) -hydnjo talk 23:51, 24 December 2008 (UTC)[reply]

HA HA! but that doesn't really help. I don't think this guy knows what he's talking about (I don't either). ♫Death gle an er 00:42, 27 December 2008 (UTC)[reply]

Hardware design[edit]

I've been interested in electronics for a while, and I've recently found myself becoming more and more fascinated by digital hardware design (the kind you hook up to a computer). The problem here: I know very little about it.

Does anyone have any links/book titles regarding layman/DIY hardware design? I'm especially looking for a simple way to pack up numbers and transmit them over USB, since - should I pursue this any further - the first hardware I'll build will probably be sensors and the like. As for the software end, this shouldn't be too great a problem; I'm sure I could write a Linux kernel module that unzips a few numbers and dumps them somewhere in /proc.

I'm aware that most DIY hardware uses RS-232, but that standard is, well, OLD. My computer doesn't even have an RS-232 port. So I thought it'd be better to delve into USB immediately. I've read that USB microcontrollers are pretty cheap anyway.

P.S. I decided to put this here rather than in /Computing, since I'm primarily interested in the non-computer part (except for the SoC part, if you really want to call a microcontroller a computer).

Thanks in advance! --Link ^(t•c•m) 11:18, 24 December 2008 (UTC)[reply]

Lego has a robotics line that comes with lots of useful bits and pieces. I think it's called "mindstorm". You can just get a couple of their gizmos and then see what you can add or build yourself based on that. Should have known we have a page Lego Mindstorms.76.97.245.5 (talk) 11:37, 24 December 2008 (UTC)[reply]

RS-232 is still very common in the DIY world, as you noticed. Ultimately, once you get downstream of the communications controller, it shouldn't matter if you are RS-232 or USB, but I suspect you will have more options for connecting equipment with 232. Incidentally a USB to 232 converter costs about $10. Moving beyond that, if you like very low level hardware design, you might want to look at the LPT interface. Unlike USB and RS-232, LPT allows one to set and hold individual bits for arbitrary lengths of time, which can be very useful for low level digital experimentation. At a higher level, I heavily recommend the products of Rabbit for high-end hobbyist projects. Starting at around $200, Rabbit provides a 40 MHz single board microcomputer that supports ethernet, rs-232, and multiple A-to-D and D-to-A. The Rabbit design runs a single program at a time, written in a variant of C, and is quite versatile. Starting out you'd want a "starter package" which includes manuals and software for doing the programming. We use Rabbit single board computers fairly often for research applications. Dragons flight (talk) 13:11, 24 December 2008 (UTC)[reply]

The PIC microcontroller and the I²C bus are worth a look if you want to get down to basics. Dmcq (talk) 13:41, 24 December 2008 (UTC)[reply]

PIC is OK if you want to build your own board - but ready-made development systems are expensive. I²C is cool though. SteveBaker (talk) 02:07, 25 December 2008 (UTC)[reply]

I strongly recommend the Arduino range of microprocessor motherboards. You can interface to them with USB - they are dirt cheap (Around $25 for a 'developer' board) - there is a HUGE community of users - and the board design is 'opensourced'. The tools work under Linux, Windows and Mac - and those are also OpenSourced. SteveBaker (talk) 14:53, 24 December 2008 (UTC)[reply]

SparkFun.com has a variaety of hobbiest electronics componants, including a few dev-boards with built in USB interfaces. And some USB->serial components. APL (talk) 15:26, 24 December 2008 (UTC)[reply]

The sparkfun boards are around $100 and have nothing like the support or functionality that Arduino cards have at a quarter the price. SteveBaker (talk) 02:07, 25 December 2008 (UTC)[reply]

Arduino seems very interesting. Thanks! --Link ^(t•c•m) 09:08, 25 December 2008 (UTC)[reply]

I noticed this discussion before but wasn't aware of this at the time. You may want to look at the Sanguino instead (technically it's a varienty of the Arduino I guess and is mentioned in the wiki page but you may not have noticed it). While designed for the RepRap project, it's like the Arduino but more powerful in most regards and is mostly compatible. May be a little harder to get some of the components but they are available from the RepRap research foundation Nil Einne (talk) 12:52, 9 January 2009 (UTC)[reply]

on chemistry[edit]

Which is basic manganic oxide? MnO(OH)2 or Mn2O3? —Preceding unsigned comment added by Sriraga (talk • contribs) 14:48, 24 December 2008 (UTC)[reply]

The articles linked from Manganese oxide may be of some help. SteveBaker (talk) 14:50, 24 December 2008 (UTC)[reply]

We don't have a page on Mn(OH)₂, but you will find it listed in the Solubility table or as pyrochroite in the minerals. Homework at X-mas?? 76.97.245.5 (talk) 18:09, 24 December 2008 (UTC)[reply]

My guess is that the alkali article may help. It's been a long time since I studied chemistry, but I think the OH group basically answers the question for you. Nimur (talk) 19:26, 24 December 2008 (UTC)[reply]

A scientist today?[edit]

I'm not sure if this should be in the Humanities section, but I'm looking for a current scientist who captures the characteristics that made Darwin successful, such as compassion, dedication and vision. Who is a current scientist who is expanding the horizons of knowledge today, and how does their work reflect this dedication to science? Thanks. —Preceding unsigned comment added by 98.226.140.27 (talk) 17:36, 24 December 2008 (UTC)[reply]

E. O. Wilson stands out.--Eriastrum (talk) 18:04, 24 December 2008 (UTC)[reply]

Since you didn't say biologist but scientist my money is on Stephen Hawking. If you are looking for s.o. younger this list may have some candidates [1]76.97.245.5 (talk) 18:20, 24 December 2008 (UTC)[reply]

You could go for Rupert Sheldrake, who is famous for unpopular theories which are the subject of much debate: or maybe James Lovelock.

--TammyMoet (talk) 18:26, 24 December 2008 (UTC)[reply]

You might also want to read about Great Man Theory, which explores the idea that heroic accomplishments of single individuals may actually be overstated in importance. Some historians consider that the impact of one man (such as Darwin, or the hypothetical contemporary who you seek) is a defining element of the narrative of history; others consider this perspective as flawed because it elevates small accomplishments into the positive-feedback mechanism that perpetuates the impact and importance of said person. Complicated. Nimur (talk) 19:29, 24 December 2008 (UTC)[reply]

Thomas Edison, I think, has a "Great Man" reputation but of a different kind from an over-rated minor discoverer. He was certainly a very intelligent person and very important practical things were developed in his lab. but it seems impossible that one man could get as many patents as he did. I think many of his patents were inventions of his assistants, and were assigned to Edison. Before he hired an assistant, he gave them an intelligence test to see if they were suitable. What he needed were craftsmen to make models of his inventions, but I think he was also looking for important suggestions from intelligent craftsmen that he could take over as his own. One of the questions on his intelligence test was, "Where is Timbuctoo?" What has that to do with craftsmanship? Edison also had copious financial aid for his R and D work from banker J.P. Morgan, which helped him get all those patents. – GlowWorm —Preceding unsigned comment added by 98.17.46.132 (talk) 21:08, 24 December 2008 (UTC)[reply]

Brings up the principle of what rises to the top... urg. I'm for E.O. Wilson for content over form. Julia Rossi (talk) 22:53, 24 December 2008 (UTC)[reply]

Note that Thomas Edison did not start out with "copious finances." He started out as a penniless itenerant telegrapher who worked after hours on improvements to the device. Business men invested in his projects because he had a track record on improving telegraph devices and inventing new and useful electromechanical devices. As for the view that he just hired smart people and then patented their inventions as his own, the writings of Jehl and others of his workers refutes this. He gave them assignments, then constantly went around working with the many "pairs of hands" at work in his lab. Jehl said that if TAE was sick or away, the pace of invention slowed mightily. His lab notebooks also show the sequence from idea to assignment to improvement. Further, few of his assistants invented anything of note after they left his employment, Nikola Tesla being a notable exception. The phonograph was clearly Edison's invention. The practical incandescent light was a team effort, but he was at the center of it. Dickson's work on the motion picture is something of an exception, with more independent invention by Dickson. Edison (talk) 06:23, 25 December 2008 (UTC)[reply]

As people are talking about Edison, Craig Venter comes to mind. Icek (talk) 06:44, 25 December 2008 (UTC)[reply]

Another thing about Thomas Edison is that he lived at the right time in history for his talent to be of use. Knowledge of electrity and magnetism had advanced to a "tipping point" where many great practical advances suddenly became possible. If he had lived 50 years earlier, his particular talents would have found no outlet and he would have been an unknown. – GlowWorm —Preceding unsigned comment added by 174.130.253.174 (talk) 08:01, 25 December 2008 (UTC)[reply]

Edison said, "Invention is 1% inspiration and 99% perspiration". However, Nikola Tesla worked for Edison for a time, and here is what he said about Edison, "His method was inefficient in the extreme, for an immense ground had to be covered to get anything at all unless blind chance intervened and, at first, I was almost a sorry witness of his doings, knowing that just a little theory and calculation would have saved him 90 percent of the labour. But he had a veritable contempt for book learning and mathematical knowledge, trusting himself entirely to his inventor's instinct and practical American sense." Edison had told employee Tesla that if he could make a certain invention by a certain time, he would pay Tesla $50,000. Tesla did the job within the time limit, but Edison would not pay him. So Tesla had a grudge against Edison; but that does not mean he was wrong in what he said of Edison. I suspect there was ill will between them even before the $50,000 incident. Even today there is sometimes ill will between a talented employee and a manager who is not as good as the employee. It is said that two kinds of people get fired – the very best and the very worst. – GlowWorm —Preceding unsigned comment added by 174.130.253.174 (talk) 14:43, 25 December 2008 (UTC)[reply]

The claim of a $50,000 promise was first mentioned by Tesla decades later and some present scholars doubt its truth. That would have been more than the initial capitalization of the company! It is hard to find what the claimed improvements were, and in fact Tesla left when he was denied a small raise. Sounds like a fantasy. Edison (talk) 16:45, 26 December 2008 (UTC)[reply]

Not that anyone asked, but I would argue that Darwin's compassion had nothing to do with his success. His dedication was far more prominent, with vision as necessary-but-insufficient quality. --98.217.8.46 (talk) 21:12, 25 December 2008 (UTC)[reply]