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Incidentally, all elements have unstable isotopes. Bismuth's are pretty rare, but they do exist!

Bismuth obsessive will rejoice in the web site of the Bismuth Producers Association.

I prefer Tums, myself.

However, intense research of carbon is what led to the discovery of buckyballs and nanotubes. Perhaps there other cool forms of silicon which are yet to be discovered.

On a different topic, how do the NASA researchers propose to connect the nanotubes in a useful way? I can understand growing the tubes on a silicon wafer and filling in the surrounding space, but this just produces a bunch of parallel wires not a designed circuit.

AlpineR

However, intense research of carbon is what led to the discovery of buckyballs and nanotubes. Perhaps there other cool forms of silicon which are yet to be discovered.

On a different topic, how do the NASA researchers propose to connect the nanotubes in a useful way? I can understand growing the tubes on a silicon wafer and filling in the surrounding space, but this just produces a bunch of parallel wires not a designed circuit.

AlpineR

However, intense research of carbon is what led to the discovery of buckyballs and nanotubes. Perhaps there other cool forms of silicon which are yet to be discovered.

On a different topic, how do the NASA researchers propose to connect the nanotubes in a useful way? I can understand growing the tubes on a silicon wafer and filling in the surrounding space, but this just produces a bunch of parallel wires not a designed circuit.

AlpineR

Where did you check?

"Francium's most stable isotope, francium-223, has a half-life of about 22 minutes. It decays into radium-223 through beta decay or into astatine-219 through alpha decay." source

In all three of the most stable isotopes, alpha decay is less likely than beta decay for the first step, and if you look at the decay trees here, you'll see that you are pretty much guaranteed to get some beta decay someplace along the line.

This appears to be the abstract for the announced results. Note the lack of words like "round" in the abstract and article. You may need a subscription to Physical Review Letters to reach it and download the paper.

This appears to be the abstract of the paper of Miller and Frank attempting to explain the phenomena. You will have to accept cookies to get any sort of information out of the APS site.

This seems to be the experimental project page. It doesn't appear to be an informative resource for the uninitiated.

I'd never read a nuclear physics paper before, so I wasn't sure what to expect. It looks like straight pQFT calculation with the Feynman diagrams, etc. would be computationally intractible for these problems, so people are always looking for reasonable approximation schemes. I guess the ones that had been used in the past didn't factor in relativistic effects as much as they should have, and the recent models corrected this.

I'm an intern php faker at thomas jefferson national accelerator facility this summer. I work in the group with the FEL (Free Electron Laser). Anyhow, apparantly if youwere to wave your hand infront of the beam, it'd lop it off and not cauterise it, therefor you'd be handless and bleeding to death. They're making it even more powerful. Put in a new super conducting cryomodule(spelling) yesturday. 3 linear accelerators and shit. the beem moves at near light speed. it's all very impressive.
Anyway, the US Navy funds this project in addition to DOE. Apparantly they used the old one for blowing up missle nose cone material and shit. It would in fact be cool to point that thing at someone. Too bad it's all in this recycled circle thingie, and is the size of the damned building.

Electromagnetic radation (nonionizing) like the microwave is different than particle beams (ionizing).

You're basically correct, although the situation is little more interesting than that. For example, anyone who's ever put a light bulb or an AOL CD into a microwave oven will have seen a fair bit of ionization. There are even industrial ultraviolet lamps that use microwaves to ionize mercury vapor inside a sealed bulb. However, in these cases electrons are being accelerated to high energies by the electric field of the microwave radiation, so it's not really the microwave radiation itself that is doing the ionizing.

Also, red light can be considered "ionizing radiation" if it happens to land on a molecule of chlorophyll. However, this is a special case. Normally electromagnetic radiation has to be in the ultraviolet or above before it is considered ionizing.

Quick review: gamma rays, x-rays, ultraviolet, visible light, infrared, microwaves, and radio waves are all the same thing - electromagnetic radiation. Each "type" above refers to a particular range of frequencies. The energy per photon is directly proportional to the frequency. Microwaves therefore have less energy per photon than visible light, and much less energy per photon than x-rays or gamma rays.

The energy of an electron beam can range from something comparable to an x-ray photon (e.g. 25keV in a television) up to several GeV in nuclear physics research labs.

Some types of radiation, like positrons and neutrons, can affect matter even at near-zero kinetic energy. Positrons will combine with electrons, converting their mass into gamma radiation. Neutrons can be absorbed by an atomic nucleus, causing it to release other radiation or (in some cases, like uranium) fission.

What makes them costly is extracting and refining them, but that is unlikely to be any cheaper on the moon if it involves space travel and rockets.

The Thomas Jefferson National Accelerator Facility in Newport News, VA, has a Linux Farm of a hundred or so boxen running Linux for data processing and storage. Go JLab!

The Thomas Jefferson National Accelerator Facility in Newport News, VA, has a Linux Farm of a hundred or so boxen running Linux for data processing and storage. Go JLab!

As was previously noted, the rules apply to technology created/procured after mid-2001. But it wouldn't hurt to change what you've got anyway.

With thousands of pages, I'd write a program to read through all of them, labeling whether they seem to be okay as is, or if not list what elements may need work, the most common example being "add alt tags to images," but also audio or video files that could use transcription, server-side image maps, and that sort of thing. If all your html files are on one server, this is pretty easy, but you could also modify a web crawler to scan multiple servers. There are web-based checkers that do this sort of thing, including W3C's own HTML validator, but you'll probably want to write your own, dealing only with the issues you find really require changes.

As to what you're looking for, I'd spend some time browsing your sites using lynx. Navigation and comprehension doesn't have to be perfect, but it should seem basically usable. The W3's guidelines give all sorts of specific suggestions, but for the most part, browsing in lynx and applying common sense will obviate the areas that need work.

Some of JLab's pages are very visual, but most just need alt tags added. For pages that need changes, look at http://www.jlab.org, which has essentially one image cut into 30 GIFs to allow pretty mouse-over highlights on its links. There are essentially three choices for this sort of page.

1) Parallel pages. Put a "text-friendly version" link at the top, with a parallel, text-friendly version. This is only necessary for certain pages - keep links on the pages the same and just put alternate versions of each page as it's needed. And I wouldn't go text-only, just text-friendly....

2) Text-only makeover. Redo the page to cut out the unnecessary graphical frills you put so much work into creating, thereby having *only* a text-friendly version.

3) Dual-use makeover. Redo the page to use unnecessary frills, but with text-friendliness in mind as well. This doesn't really take any more work than the doing a text-unfriendly design, but since you're doing it over, text-unfriendly design, but since you're doing it over, it's certainly a hassle.

Ultimately I think dual-use, accessible design is what the legislation in question is trying to encourage.

Jefferson Labs with support from the DoE and Southeastern Universities Research Association have created a the most powerful tunable laser that uses a particle accelerator's electron beam as its source of light. It's called the Free Electron Laser (FEL) and has been able to produce such items as this with a greater quality and at less cost (cost=power consumption). This laser has many potential uses, including usage in military targeting systems for offensive and defensive (like disarming a nuke from miles away) systems. It could also be used to produce man-made fabrics that have been altered at a microscopic level to be as soft as wool (of course, creating such nano-fibers as this article claims to be so unique). Interesting, huh?

Jefferson Labs with support from the DoE and Southeastern Universities Research Association have created a the most powerful tunable laser that uses a particle accelerator's electron beam as its source of light. It's called the Free Electron Laser (FEL) and has been able to produce such items as this with a greater quality and at less cost (cost=power consumption). This laser has many potential uses, including usage in military targeting systems for offensive and defensive (like disarming a nuke from miles away) systems. It could also be used to produce man-made fabrics that have been altered at a microscopic level to be as soft as wool (of course, creating such nano-fibers as this article claims to be so unique). Interesting, huh?

Jefferson Labs with support from the DoE and Southeastern Universities Research Association have created a the most powerful tunable laser that uses a particle accelerator's electron beam as its source of light. It's called the Free Electron Laser (FEL) and has been able to produce such items as this with a greater quality and at less cost (cost=power consumption). This laser has many potential uses, including usage in military targeting systems for offensive and defensive (like disarming a nuke from miles away) systems. It could also be used to produce man-made fabrics that have been altered at a microscopic level to be as soft as wool (of course, creating such nano-fibers as this article claims to be so unique). Interesting, huh?

All this talk is great, but not going to happen within any reasonable length of time. For example, recently there was a law past that says that not only sites that are owned but also sites that are partly FUNDED by ANY government institution MUST comply in every way to the disabled. This decision was passed overnight, and effected hundreds of businesses and government sites. Over here at the Thomas Jefferson National Accelerator Facility www.jlab.org, due to the fact we are funded by the DOE, we were suddenly attacked by the lawyers for the lab for not being able to comply with the vision-impaired web browsers with our current workload and resources. See, for a long time, the only resources available to gov't sites was Pico and a UNIX server. This means no SSI, no C progs, no database, and limited Perl use. Only recently were we allowed to start develop web apps (using ColdFusion and IIS, ironically) and start placing our site into database. Now, every other site in the world can adapt to change very quickly; changing one or two files to alter the design of the site. Govn't facilities cannot do this because of moronic regulations that are ineffective and hampering to the web staff. Another problem, which I am led to believe is a reoccurring theme across gov't sites, is that our web teams are understaffed, under-appreciated, and undersupplied. If it weren't for the fact that 95% of the development here at JLab came from student interns who are working for peanuts, there would never be any progress. And the support of the local community just isn't behind us. They use us to post information and do the dirty work but are slow to act when we need more help. With this kind of crud going on, there is no way in the world that a pre-existing gov't site could possibly conform to the standards set by Congress. The governments goal is not to make a decent web site, it is to serve the people through archaic paper-shuffling and 1on1 "assistance". It is yet to realize the full potential the web has to offer, although Gore and his team did an excellent job this past four years to get .GOV going strong. There is much work to be done on government sites, but alas, there is no real push to get the work completed. HOPEFULLY, they will turn a "blind eye" to the Americans with Disabilities Act clause that effects gov't sites. If not, I'd rather look for a new internship than edit 8000+ HTML pages to add ALT tags.

I've measured it, and it goes so close to dark the difference isn't worth talking about. The phosphors are clearly very short lived (less than a millisecond). The trace from a photodiode looks like abs(sin(x)).