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Comment Re:Is Hydrogen more dangerous than other gasses? (Score 2) 479

Does hydrogen have a lower flashpoint or some other quality which makes it more dangerous?

doi:10.1016/j.ijhydene.2009.04.012
Limits for hydrogen leaks that can support stable flames, International Journal of Hydrogen Energy Volume 34, Issue 12, June 2009, Pages 5174–5182

Hydrogen is an unusual fuel. It has a high leak propensity and wide flammability limits, 4–75% by volume. Among all fuels, hydrogen has the lowest molecular weight, the lowest quenching distance (0.51 mm), the smallest ignition energy in air (28 mJ), the lowest auto-ignition temperature by
a heated air jet (640C), the highest laminar burning velocity in air (2.91 m/s), and the highest heat of combustion (119.9 kJ/g). Hydrogen flames are the dimmest of any fuel. Hydrogen embrittles and attacks metals more than any other fuel.

Mind you, this is from researchers generally inclined towards the use of hydrogen.

Submission + - The Cybersecurity Industry Is Hiring, But Young People Aren't Interested (vice.com)

Daniel_Stuckey writes: Cybersecurity, as an industry, is booming. According to the Bureau of Labor Statistics, jobs as network systems and information security professionals are expected to grow by 53 percent through 2018. Yet, just like Hoffman doesn’t have any interest in plastics in 1963, young people today aren’t interested in getting jobs in cybersecurity. By all accounts it's a growing and potentially secure, lucrative job. But according to a new survey by the defense tech company Raytheon, only 24 percent of millennials have any interest in cybersecurity as a career. Forty percent of respondents would want to be a "TV or movie entertainer," while 26 percent had interest in being a lawyer. (Respondents could pick multiple careers.)

Submission + - Dolphins' Hunting Technique Inspires New Radar Device (ibtimes.com)

minty3 writes: The twin inverted pulse radar (TWIPR) made by a team from the University of Southampton in England uses the same technique dolphins do to capture prey. Like dolphins, the device sends out two pulses in quick succession to cancel out background noise.

Comment Re:Good. (Score 2) 699

Funny that the rise in shingles cases has occurred since varicella vaccination became common.

What's changed is that there is no longer a large amount of chicken pox virus floating around the community, constantly challenging folks' immune systems. To get exposed you now have to go to a doctor and buy it. (This is the "shingles vaccine".)

For many diseases, such as polio and measles, vaccination is undoubtedly a huge good, preventing a huge number of deaths and tragic illness. But for varicella, the vaccine may result in more harm than good.

Comment dot rad (Score 1) 37

The one gTLD that makes sense would be .rad, though I haven't seen this proposed. The idea is to link nationally or internationally assigned radio call signs, to a URL: call_sign.rad.

This is sensible as a gTLD, as there is a one-one correspondence between call signs and legitimate owners. There is a need and value to having a (somewhat) reliable or trustable way to locate the radio stations on the web.

Comment Nuclear winter and the big bombs of the 50's (Score 1) 92

I wonder about the climate impact of the series of multi-megaton surface blasts by the US and USSR in the 1950's and 1960's. These tests put both dust and radionuclides into the atmosphere in large, possibly globally-significant quantities. When we see surface temperature changes over the last 50 years, how much of that is a recovery from an abnormal climate?

Comment Oncologists and the risk of low-dosage radiation (Score 1) 140

Why haven't radiation oncologists produced good data on this? Many, many people are exposed to substantial radiation doses in the treatment of cancer. And their progress and outcomes is tracked by the tremendous statistical measurements of modern oncology. (This statistical rigor is a big chunk of the improvement in cancer treatment over the last generation or two).

Of course there are huge confounding factors, including that the patient already has cancer, is exposed to carcinogenic chemotherapy regimens, and so on. But it would seem to me that with such a large dataset--along with the long-term tracking--the quantitative danger and damage due to smaller and smaller doses of radiation would be measurable.

Comment Nanoscale production of zinc oxide (Score 1) 406

I ran across this paper on nano scale production of zinc oxide by a laser ablation method. If the ZnO is being used as a catalyst, nanostructures are useful for their increased surface area.

This might be useful for those amateur chemists wanting to build their own at home.

Yang, Li, Paul W May, Lei Yin, and Tom B Scott. 2007. “Growth of self-assembled ZnO nanoleaf from aqueous solution by pulsed laser ablation.” Nanotechnology 18(21):215602. Retrieved April 5, 2012. http://www.chm.bris.ac.uk/pt/diamond/pdf/drm17-931.pdf

Comment Preprint on arXiv (Score 4, Informative) 169

A preprint is available on arXiv at http://arxiv.org/abs/1110.2490

A nuclear transition in triply-ionized 229Th has been found which is particularly insensitive to external magnetic fields and electron configuration, which gives the potential for a very stable clock,several orders of magnitude better than current clocks if phase comparisons can be made across a scale of days or weeks. The transition energy is at 163nm (in the ultraviolet). To take advantage of this clock an extremely stable laser at this wavelength (using current best clocks) will need to be created.

Comment Re:Next time read at least the complete summary (Score 1) 1127

It doesn't actually work that way - not in practice, at any rate. That's economics theory over-applied.

Let's suppose child porn didn't exist - a hypothetical situation, but also an admitted impossibility. If child porn didn't exist, why would anyone know to make it? How is this "demand" being demonstrated? If some guy says "I want naked pictures" you are not necessarily going to oblige him unless your intent is to do so anyway, correct?

The whole "you create demand for the creator's work" argument is a bit fallacious, I think.

Now, distribution, on the other hand... yeah, that should carry heavy penalties. And the creators should be publicly executed.

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