* Posts by fortran

72 posts • joined 10 Mar 2013


Beautiful model to explain the universe to physicists



I think it is Case Western Reserve university, not Cape Western Reserve.

Now Google backs everyone's favorite trade pact: The TPP


USA-ians selling items abroad?

TPP is a bad agreement, but it is hardly the only thing holding back USA companies from selling all over the world. ITAR is far worse.

I'm a Canadian, residing in Canada. ITAR regulations made it difficult for me to buy a 9 DOF (gyroscope, 3D accelerometer, magnetic inclinometer) board. Sure, I can see how that might be used in a cruise missile. Those same regulations also showed themselves when I wanted to buy a digital oscilloscope kit (for Arduino) and an educational kit for measuring the capacitance of a capacitor.

I recently tried to buy some 6/64 inch machine screws that are 9/16 inch long from McMaster-Carr. ITAR makes it impossible for them to sell something this potentially damaging to foreign citizens (read terrorists). They can only sell to companies.

The USA is so busy shooting themselves in the foot over foreign terrorism issues, nobody will buy from them because they are too much of a PITA.

Bill Gates cooks up poultry recipe for Africans' paltry existence


Re: Better idea

Having looked a little into permaculture, I would have lumped Guinea Fowl in with chickens. And turkeys, geese, ducks, .... I had read they are noisy. I think having more than one kind of fowl is better than just a single kind.

While many chickens eat grain, chickens are also carnivores, and will eat insects and worms. That is how they evolved.

Yes, disease can be a problem. But it is a problem for other animals as well.

One good thing about chickens (and probably other fowl), is that they are quite efficient at turning food into meat (or eggs).

Linux greybeards release beta of systemd-free Debian fork


bsd and systemd

Concensus I've seen, has it that BSD cannot run systemd. Lately on Debian/stable, I've noticed that bsdutils is not being upgraded. The reason? On Debian/stable, bsdutils now depends on systemd! I've downloaded the source package, and you can compile it with no inclusion of systemd.

I will be moving to Devuan. Including my failed attempt at understanding Gentoo.

India orders 770 million LED light bulbs, prices drop 83 per cent


What kinds of drivers? (not vehicle)

There are quite a few ways of driving LEDs from mains. Are they using ancient technology which generates a ton of heat (wasted electricity)? Or something newer (qr buck?) which is much more efficient? As the LED themselves won't wear out for quite a while, they may have just bought themselves a huge baseload of electricity. Granted, probably less than now, but they could save a while bunch more electricity with something efficient.

Some EE probably has a better description for these new drivers than I used.

Google spews critical Android patch as millions of gadgets hit by Linux kernel bug


On Poor Writing

I starting reading comments on CVE-2016-0805 (and 0819) last night. Trend Micro had a comment which suggested that the issues behind 0805 had been sent to manufacturers quite a while ago, and were dealt with in the patch dated Feb 2, 2016. Now first thing this morning, I read this? With no coffee in the system. This no rooting of phones is an annoying rule, if the reason to root the phone is to get security patches to the OS. Maybe if I drink my coffee, this will all go away?

There is no sense unwrapping the new phone, if it isn't going to be possible to put a secure OS on it for months, or ever.

Microsoft hits the gas in drive to recruit autistic techies


Re: Um, this is ridiculously illegal

As near as I can tell, you are correct. As the laws in most "western" countries stand, this is illegal. Somehow a hodge podge of rules were assembled which seem to do a reasonable job at making it more difficult to discriminate against major and minor elements of society. But it seems that the only way to reduce discrimination against some socially "disabled" people is to have prior knowledge. And as near as I can tell, the characterization of how many people like this are employable, is that they are trace (not major, not minor). And being a trace element of society, they will never have the economic or political power to get attention from government.

When I've had jobs, I seem able to work with my fellow employees reasonably well. There are some problems, but I don't think that is unusual. My problem is with the hiring process itself. Process and rules of thumb used to process applications make assumptions about me, which do not give me a fair chance.

Before people think I am just whinging. I didn't know I was on the spectrum until I had already been in the workforce for about 20 years. And I tried for about another 10 years to find employment knowing that I was on the spectrum, but not saying anything to employers. It doesn't work. Potential employers have to know, in order to give me a chance.

The alternative is a complete rewrite of the hiring API and libraries. Something we've hacked together since the Industrial age began.

It really should be rewritten anyway, but it would be expensive.


If only it wasn't M$

At least some employers are starting. I'm good at computers, but I am good with lots of tools. Computers are just another one. I'm looking for that open minded employer in Materials Science and Engineering. Or that uses Materials Science and Engineering professionals.

Playing with graphene? All the cool kids are using TIN – atom-thick sheets of stanene


The no longer stable isotopes

Sn-112 undergoes double electron capture (somewhere less than 1E21 year half life), Sn-124 undergoes double beta decay (somewhere greater than 1E21 year half life), and Sn-122 has people suspecting it also undergoes double beta decay.

Leaving tin with 7 stable isotopes.

A source for this information is Jefferson Lab. A lot of older web data shoes all 3 isotopes listed as stable.


Picking Nits: TIN versus Tin

Spelling out the element in uppercase is not correct, and is less than useful when the font you are using does not employ arms across the top and bottom for the uppercase 'i'. Which means it gets mistaken for a lowercase 'L', and the number '1'.

Is the person talking about Tin (the element), TiN (titanium nitride), TlN (Thallium nitride doesn't exist, but Tl3N does). It isn't as bad as writing about lead, which usually causes me to write about lead (Pb) to reinforce that I am talking about the metal, and not some form of graphite.

One thing I find interesting about Tin, is that just by changing the vowel, you find how many stable isotopes Tin has (ten), which is the most of any element. Of course, then things like double beta minus decay come along and turn some of the "stable" isotopes into unstable (but very long lived) isotopes.

Pale backside of lovely Luna flits past in imagery from 1 million miles out


Lunar Imaging

At any given time, 50% of the Moon is visible from Earth, and being tidally locked it is (nominally) the same 50%. When libration (correct word?) is taken into account, we can see about 59% of the lunar surface. DSCOVR will have perfect views (in many wavelength bands) many times, and could build up views of the Moon in each of those bands. As DSCOVR orbits L1 (and the Moon wobbles, and has tilt), how much of the lunar surface can eventually be seen by DSCOVR?

New Horizons: We've got a pretty pic of Pluto. Now let's get our SCIENCE on


Deep Space Network?

New Horizons and Philae/Rosetta are both pointing at problems with the "deep space network", and I think Dawn is where part of the answer lies.

A long time ago, UHouston had a robot which could roll across simulated lunar regolith and turn the surface into solar cells. Not very good ones, but there is so much "dry" real estate on the Moon compared to Earth it wouldn't matter. I believe a small amount of iron was recovered (removed) from the regolith, and that could be used for electrical interconnects (with 0 toughness during lunar night).

Ceres is quite a bit further from the Sun than Mars is, but it is still a whole pile of dry real estate.

Land at either pole, and have some robot set up solar cells on the surface to provide power. Probably a person needs to set up microwave and visible dishes in space close to Ceres, to receive signals from the amplitude challenged sources it needs to relay for. Have high amplitude laser and microwave antenna on Ceres, to send data to remote locations. Have a high intensity UV laser on Ceres that is tightly collimated. Lose a lander again, illuminate the target with UV and design parts of the lander to be fluorescent. Maybe just a big mirror (in space) is all that is needed?

I think you need to then setup receiving stations near both poles of the Moon, who can pass data back to Earth.

It may be convenient to place communications satellites in other places. But relays at the Moon and Ceres potentially allow for large power budgets, as there is so much area available to put solar cells on.

How long does a solar cell last on Ceres or the Moon? I haven't a clue.

I still think Philae's last hop found one of those sinkholes, either not yet ready to cave in or just starting to.

Why recruiters are looking beyond IT's traditional talent pool


Expanding appliant qualities is NOT sufficient

The hiring system was never designed. It is patch on patch on patch going back to when the Scots started building steam engines. There has NEVER been a rewrite!

Some functional autistics can find work (but are probably still misunderstood by the HR patch on patch on patch on ...) and some can't. More or less by definition, we are out of the box. Nearly all of the time, there is no way for an autistic who happens to be orthogonal to the hiring process to apply for a job. To use the system everyone uses, is a waste of time, regardless of how well they could do the job. Because of HOW they are out of the box.

I've only ever run across one company which hires engineers (out of Los Alamos I believe) which has a link on the careers page: I need some other way to apply. Name escapes me at the moment.

Most of their jobs relate to "national security", and being Canadian I don't qualify.

The huge flaw in Moore’s Law? It's NOT a law after all


Spelling Police

Two mistakes, a missing s and a missing capitalisation.


Johns Hopkins University - Applied Physics Laboratory

Boffins laser print flexible transistors





Watch: Nasty JPEG pops corporate locks on Windows boxes


Re: What’s going on here?

> Some of your technology may be out of date, which means this video won't play properly. Please install Flash or upgrade your browser.

My browser is up to date. Flash has been removed because it is a security nightmare, just like the fine people at TheRegister recommended.

Boffins FOAMING over a Nickel's worth of hydrogen


Hydrogen loss?

Some of the hydrogen generated, by whatever method, leaks into the atmosphere. What fraction of that is eventually lost from Earth?

NASA wants you to help space mining corp strip mine the Solar System



Who distributes documentation as a .docx file? Have they heard of PDF?

It probably is not a GPU program. The website doesn't seem to say anything on this, and I don't read .docx worth a darn.

I didn't look, but I would not be surprised if the source code is in a Zip archive, instead of a proper tarball. :-)

Canadian bloke refuses to hand over phone password, gets cuffed


Beaver pelts

If weasel, bison and bear are of interest, are moose and wolverine as well? Can we just send the live animals? You skin them. Send us back a movie of you trying to skin a live moose or wolverine.

How about different root (wheel, other) logins? Different logins set different locales. Login with a Klingon locale?

RIP Leonard Nimoy: He lived long and prospered


Maybe visit Vulcan?

Vulcan does exist, and Leonard Nimoy has visited there. If you are even in southern Alberta, Canada consider visiting. Lots of other strange sites in small places nearby, for example: Manyberries is the sunniest place in Alberta, and there is a place called One Four, which is 14 miles from somewhere else (used to be an Ag Canada research station there).

Vulcan is situated at 50.4° North latitude, 113.25° West longitude and 1050 meters elevation above the sea level.

Vulcan is a small community in Canada, having about 1,853 inhabitants.


Thank you for the memories Leonard Nimoy. RIP.

Skin colour's irrelevant. Just hire competent folk on their merits, FFS


Trace components of society?

And I am not talking about what NSA, GCHQ or whatever alphabet soup is doing.

There are economic and political reasons to deal with issues involving groups constituting between about 5 to 70% of the population. If you belong to a group that is smaller than that, it is unlikely there is either an economic or political benefit to fixing any problems.

So much of the hiring process that I have seen, has almost nothing to do with determining competency. There is a large component of the hiring process which assumes the applicant is in the major mode of the multi-dimensional distribution of human quality, and is not too far from the mode (mean, median).

If you belong to a trace element of society (less than 5%), and are not in the mainstream mode, it is difficult to find a way to let your competence be known so that you can find work.

Passing asteroid MOONS the HUMAN RACE



It is possible that all the media people are copying from each other, and the first one shifted the decimal point. The writeups I've read, has the moon being between 20 and 25% of the diameter of the asteroid. In the JPL "movie", this seems unlikely unless the orbit is large. But the parent body is not that massive, so the orbit can't be large, otherwise it would escape.

The original size estimate I seen at Spaceweather, was 680m, and the sizes from JPL are a bit less than half that. If the distance from the surface of the asteroid to the moon is 180m, and this moon is much more reflective than the asteroid is, that would explain why the inital size estimate was off by about a factor of 2.

And the media is just being "professional" in repeating what everyone else in the media are reporting.

But, this isn't my area of expertice, and I could be wrong as well.

India digs deep to bury neutrino-hunting chamber


High Background Area?

While Kerala doesn't have quite the high background as Ramsar (sp?) in northern Iran, this village appears to be on the edge of Kerala. There are no monazite placer deposits, or thorium ores in the vicinity of that village? Or are they counting on that being nearby for some reason?

Kepler's STILL GOT IT! Space telescope spots SUPER-EARTH 180 light years away


Don't forget MOST

Canada has a microsat up there, which has helped in finding planets. And typical of Canada, no (more) funding. MOST needs things to look for.


Eat FATTY FOODS to stay THIN. They might even help your heart


coconut, and muscle

Any paper which brings up coconut, has to add more words. Yes, the fatty acid chains in coconut tend to be saturated. But, the fatty acid chains in coconut tend to be shorter. Nominally, they seem to be classified as medium chain fatty acids, not long chain fatty acids. Is this important? It is different.

I've read/studied a bit about becoming muscular. The idea that to become muscular requires a carnivore diet is pervasive. I've had neighbours with plains bison (buffalo), and I have moose walking through my yard. Both moose and buffalo are extremely muscular animals, and they are vegetarians.

This morning, I found myself trying to scare away a moose who wanted to eat one of my shrubs (it was -35C or so, and we have gotten more snow than usual this winter, especially for so early in the winter).

Trying to scare away a moose is not to be taken lightly. Sorry, can't find the link. But the CBC had an article about an RCMP officer who decided to interpose his vehicle between an ordinary vehicle and a moose in downtown Prince George, BC. The moose decided to dance on the top of the police car, broke most of the windows, and in the process broke the shoulder of the police officer.

Post-pub nosh neckfiller: The MIGHTY Scotch egg


Re: Awkward sod here.

Duck Duck Go found this at food.com. Author has celiac (sp?) disease. There were other hits as well. From doing some food research a while ago, there are quite a few "flours" which can take over from wheat. It seems like the better recipes use a mixture of flours to replace the gluten in wheat, instead of just relying on one. Gums are I believe commonly involved.



Re: Armadillo Eggs

I am from NW Alberta, Canada, but I will take a chance on your questions.

I would suggest something like hot italian sausage (nominally a bratwurst?) would work for spicy pork sausage. In terms of being Texas-like, I would suggest a mixture of dried (and crushed) chillies. A person could use a single kind of chilli, but a mixture tends to have better flavour. I would include chipotle (smoked jalapeno) in this. Cumin.

I think garam masala would work, but I would give it a different name than Armadillo. Likewise, I think jerk seasoning would work (Jamaica Eggs?).

I was wondering about habbenero (or scotch bonnet) peppers myself. I've never had a ghost pepper, but that might work too.

Bisquick is a self rising flour, I don't think it is whole grain in any respect. I've added sourdough (mother) to Bisquick to get it to rise (instead of milk). I asked the manufacturer about this, and got back a snotty response about unapproved uses.

Yes, 1C would be 1 Cup.

Shake and Bake is a mixture of bread crumbs and corn meal (could be corn flakes?). It contains a variety of oils and other things (for binders). The box I have, has 2 bags of mixture in 152 grams of package.

Lights OUT for Philae BUT slumbering probot could phone home again as comet nears Sun


Nuclear battery development

I don't believe a country needs to have nuclear reactors in order to develop a nuclear battery (radioisotopic thermoelectric generator). While it isn't ideal, I believe the Th-228 decay chain could be used for this task. Others have had this idea as well. The presence of a radon species can be good or bad. But, maybe it is possible to take advantage of this, to eject Rn-220 and its daughters from the spacecraft? This would allow one to avoid the monster alpha of Po-212 (almost 9 MeV) and the monster beta of Tl-208. Capturing that alpha wouldn't be much of a problem, but the range of that beta is inconvenient.

Linux systemd dev says open source is 'SICK', kernel community 'awful'


Re: Oh please...

I was running Debian. My server is running Gentoo (make.conf has -systemd) and I am thinking of Dragonfly BSD for my desktop machine.

Lennart, your programs may be useful, they tend to not follow UN*X philsophy. Buy The UNIX Programming Environment and Software Tools. Read them to the point you have almost memorized them. Then if you still want to do programming, do things that follow in that philosophy.

But, I hate pulse, I disable avahi binaries, and in Gentoo my make.conf comment is just the start. I really think you should be working in Redmond for M$.

Reg reader fires up Pi-powered anti-cat garden sprinkler system


Yellow Bellied Sapsuckers?

I wonder if this would work with that "wonderful" woodpecker known as the yellow bellied sapsucker? Or as I like to call them, yellow bellied tree killers. Woodpeckers often hammer at wood, to find a bug to eat. This particular woodpeckers hammers at the wood to get at the sap underneath. And then does so again a cm or so away. And again. It can eventually "ring" a trunk with a checkerboard pattern of holes, which often kills the tree above the "ring"

I think the one commenter was referring to CatStop at Lee Valley Tools for one item, not sure of the other one (didn't visit URLs directly). CatStop has a PIR, and unleashes 124 dB ultrasound at the cat. Are birds afraid of ultrasound?

Tesla's top secret gigafactories: Lithium to power world's vehicles? Let's do the sums


Extracting almost everything?

Most ores seem to revolve around just extracting one or two metals. For example, copper ores. It can happen that the "one metal" has trace amounts of other things of interest, so you can find copper ores where there is enough trace silver or gold to warrant treating the copper in a special way.

But people seldom look for "man" metals all at once in the same location. The "rare earths" are an exception. Even still, there is a tendency to ignore components even with rare earth deposits, which often means ignoring thorium or uranium, which later on causes a problem (I think that uranium, thorium and the rare earths should almost always be considered a single group as far as mining goes).

On Earth, we see significant price differences (pennies per kilogram up to say tens of thousands of dollars per kilogram) across metals of interest. Which is about a range of 1E7:1. To get any material to high orbit (or further) from Earth, tends to cost thousands of dollars per kilogram. Our ratio of expensive to cheap goes from 1E7 to something like 2:1. When I've looked at mining on the Moon, the idea was to cascade as many processes as one could, so that one tries to recover everything.

Maybe someone practising that philosophy could take a stab at lithium?

Venus Express to get final acid bath before crashing to surface


Volatile metallic compounds?

I hadn't really followed VenusExpress, and visiting the site (Javascript required) produced no joy. Was Venus Express outfitted to detect volatile metallic compounds? Nickel carbonyl, Molybdenum oxide, Osmium oxide, ...? If so, did it find any?

BBC hacks – tweet the crap out of the news, cries tech-dazzled Trust



The BBC used to have a good reputation, and perhaps relatively speaking it still might in some ways. Your article about removing customization to become productive applies a bit here in my eyes. In Canada, almost all of the media is concentrated in a handful of companies. It is almost that there are 2 newspapers and maybe 3 TV stations, all serving the same regurgitated crap (in the case of CTV, whatever the CEO of Bell deems worth presenting). The BBC hasn't fallen that far in my eyes.

But BBC Sport is following most all other Sports organizations down their own version of a sewer. If nothing else, the purpose of a Sports organization should not be to get all managers fired every year.

Twitter and facebook really don't mean anything to me in the context of "news".

News articles should be accurate, and they should not be cut and pasted. Any of us could write scripts to generate a "news" article given N news sources. And this random source might even be indistinguishable from articles with human input.

Boffins working on debris float models to track MH370 wreckage


French non-image is different

Looking at a bunch of news articles, there seemed to be a couple of ongoing themes: the French said it was not an image, it was a reflection; and two, positions were not given for where this non-image came from.

I guess another search day has just started (hour or so ago). In one of the reports, something related to a location was let go, this non-image was from 850 km North of the Chinese and American image locations. Is the eastward drift of water that much further north about the same as the first two sites? Which are more or less on top of the Southeast Indian Ocean Ridge. To me, it looks like they are just south of that ridge. Fancy trying to find a plane in an underwater mountain range?

In any event, if the French location is that much further north, maybe it is one of the doors from the 777? Passengers or crew opened the door, and bailed out?

The write up in the news seem to suggest the search aircraft only have a couple of hours of loiter time on site, unless they are carrying internal fuel bladders (and nothing is ending up in the news about that). But, that Canadair aircraft, just on a full load of fuel should have about 8 hours of loiter at the search site. The Grumman 5 (?) might have 4 hours of loiter time. I have no idea how that Airbus 319 is contributing.

I think it would be better if the countries with spy satellites taking pictures of that area, would just dump them somewhere public and let the crowd look. Having a handful of experts take 4 days to find one or two images is not being useful. Having a few thousand people look at pictures has got to generate more hits.

Fukushima radioactivity a complete non-issue on West Coast: Also for Fukushima locals, in fact


Re: Perfectly safe?

The image exists, I seen it in multiple news reports. There is no explanation for how the image was generated. Gamma aerial surveying seems the most likely explanation. My brain fuzzied a number. USGS says on land the signal is nominally from the top 20-25cm. Water is a bit less than half as dense, so 50-60 cm?

There are lots of ways to turn measurements of some kind at a set of positions into a map. To sample enough locations by taking water samples for the image that I pointed to, would have taken quite a while. To fly a plane (or set of planes) over that area is much more feasible.

Everybody knows inverse square law for the point source and point detector. For a point detector and a line source, it is just inverse distance. For a plane source, intensity is independent of distance. (infinite line and infinite plane). If the source extends over more than 120 degrees of angle (2D), the line source effectively is of infinite extent. A similar argument follows for a planar source of large extent.

Sure, the measurement is saying on the order of 1 decay per second per cubic meter of water, and we are guessing that a 661 keV gamma can likely escape from something like 0.63m of water. If the plane is at 1000m altitude, a 90 degree arc defines a surface of Pi million square meters. How many of those 1 meter square surface regions have a gamma being emitted in the direction of the aircraft? The aircraft could easily have a very large NaI(Tl) detector on board. Time to go to sleep. I can't find any study that would have produced such a map, hopefully someone else can.

A 2012 Homeland Security survey in the Bay area, was seeing gross count rates of 3000 and 3500 CPM flying at 300 feet and 70 knots above Fisherman's Wharf and Alcatraz with twelve 2 litre NaI detectors. This survey treated over-water as being indicative of just cosmic ray signals.

A survey of Los Alamos county (presented 2013) showed that the only man-made sources of radioactivity found in the county, were on the Los Alamos Nuclear Reservation. Three of those sites were cesium spills.

700 PBq of Cs-137 were in the 3 damaged cores originally. A particular report says 14-17 PBq were released by the accident into the atmosphere, of which 12-15 have since entered the ocean. 3.6 +/- 0.7 went directly to the ocean. And there was 140 PBq in stagnant water (on site?). The first number I reported here was 360 PBq was total release, which is about half of the 700 that were in the cores to begin with. But I guess this paragraph says that most likely nearly all the Cs-137 that was released is in the ocean now. One slide I see shows 5 ships (1 appears to be a container ship) collecting samples from about 200 sites between 20 N and 55N, between Japan and the west coast of North America up until Oct 2012. In Oct 2011, the surface level of Cs-134 (the shorter lived) was about 25 Bq/M^3, there is a peak of about 3 Bq/m^3 at 140m depth, and a peak of about 3 Bq/m^3 at 300m depth. By June of 2012, this changed to a peak of 4 Bq/m^3 at 50m depth, and a peak of 9 Bq/m^3 at 320m depth. From previous studies of weapons test Cs-137 in the water column, the expectation was surface transport east from Japan towards North America to about the half way point, and then there was a diving current (subtropical gyre?) which was expected to take the Cs-137 down and to the south and west, ultimately towards Indonesia. The Wikipedia article on the North Pacific Gyre shows a different circulation than the IAEA document.

Apparently the total inventory of Cs-137 from weapons tests remaining in the environment in 1970, was about 290 PBq. By 2011 (pre accident) this was down to 69 PBq, of which 3% was from Chernobyl.

IAEA Scientific Forum 17-18 September 2013 Vienna, Austria


I can understand the emotion in both sides. It is disappointing to see the twisting that both sides seem to be doing to data. I just want to find truth.

Good night.


Re: Perfectly safe?

I believe the only fuel is U-235. I don't think that particular kind of reactor breed significant Pu-239.

There are a few nuclei which are described as fissile. If a fissile nucleus absorbs a neutron (being uncharged, it has no barrier to tunnel through), there is a reasonable chance that daughter nucleus will under go fission. U-235 will absorb a neutron to form U-236, and I believe most of the time, U-236 undergoes fission.

Fission literally mean to split into large parts. With the fission of U-235 (the original fuel), the split is into two large chunks, with some leftovers. There are 2 peaks in the atomic mass, 94-95 and about 136. If we add 95 to 136 we get 231. The peak at 136 is wider than the lower mass peak. So, we may find the most common sum for the 2 large fragments is in the 233 to 234 range. With U-235 we typically get some fast neutron production from the fission event, so that is where the that missing 1.x goes to. Where the cesium-137 comes from, is the 137 mass line is right near the higher mass peak. 6.19% of fissions from U-235 result in a 137 mass fragment. My chart of the Nuclides has Te-137 (2.5 s) as the furthest off stability. Te-137 normally decays by beta minus (to I-137), but it sometimes gives rise to a delayed neutron instead (Te-136). I-137 (24.5 s) usually decays by beta minus, but it can sometimes give rise to a delayed neutron (to I-136). And things branch from there, with some of the isotopes produced having measurable fractions of decays giving rise to delayed neutrons, but all the isotopes produced on the neutron rich side tending to decay by beta minus. Some of the 137 line will undergo successive beta minus decays, and end up at Cs-137. Ba-137 and Ba-137m look to be the two most proton rich fission products on that mass line. Cs-137 eventually decays into Ba-137. Some of the larger fission products could end up on the 138, 139, and so on lines, and some of the isotopes along those lines have delayed neutron emission as a decay process. Cs-137 just happens a longish half life, and consequently it gets produced at a reasonable rate in fission, and due to the half life, even over the course of the lifetime of a reactor, maybe a little over half of all Cs-137 produced in a fuel rod may decay to Ba-137.

It really would have been nice, if Lewis (or someone) would have replaced the tsunami wave height image with an image about the gamma aerial surveying of the Pacific and Arctic oceans, such as I had pointed to.


Re: Cs-137 plume

Well, if you looked at the aerial gamma survey image from the fishing article, you would see it is significantly more than 1/10 of the Pacific which is generating signal. The highest concentrations are I believe on the order of 15 Bq/m^3, and that is still close to Japan. What is currently at the BC coast, is I believe about 0.1 Bq/m^3. But, from what you are saying, it looks like the cesium is not diffusing down in the water column. I don't know where the upwelling and down draft currents are, but maybe it takes one of those down drafts to push cesium to the deep ocean.

In terms of hazard to a person in a boat or airplane, nearly all of the hazard is from gamma, but that will only be about the top meter of water due to self-shielding by the water. The radiation field will be almost independent of height above the ocean, as it approximates a planar source.

In terms of hazard to life in the ocean, it is the beta emitted by cesium which is potentially the problem. If a fish, plankton, or what have you ingests Cs-137 atoms, they will tend to follow potassium in the body. If most of the ocean is like a desert with respect to potassium, it is possible that the cesium will have a longer biological half life. But because it is nominally a kind of salt, I would guess its biological half life is probably on the order of a day. So, because some life form takes in a radioactive Cs-137 atom, doesn't mean that the atom is going to decay, and in so doing, possibly have a single beta decay possibly do some damage. And really, a single atom decaying, and in a location not close to DNA, isn't likely to do significant damage to even one cell. The gamma emitted from that kind of scenario will exit the life form in all likelihood without depositing significant energy in any given cell along the path.

It isn't fair to say alpha and beta are of minimal risk (there is no alpha involved with Cs-137). What many have pointed out is typical, and yes the beta from Cs-137 is typical. Having worked at a research reactor, I have made Cl-38 (35 minute half life), and it has a monster of a beta (5 MeV). That thing has a range of 60 feet in air. I the the end of the Th-232 decay chain has a couple of monster particles: a 5 MeV beta and a 10 MeV alpha. An alpha that energetic will penetrate all of the dead skin and make its way into live tissue. I think the rule of thumb cut off on alphas not getting through the dead skin is about 7 MeV. But as I didn't spend much time working with alpha emitters, I didn't memorize much about them. But for most alpha emitters the casual person may be exposed to, 7 MeV is still pretty hard and unlikely. I think the most likely pathway to damage is inhalation, where the alpha emitter is deposited on live lung tissue.

But, whether we are talking Cs-137 or Th-232, it is only in the few nanoseconds when the decay happens, that there is any hazard to living processes in the vicinity of that atom.


Cs-137 plume

I have gone through the calculations in 2 different ways, and get the same answer, so perhaps it is close. :-)

Fishermen on the BC coast are also concerned, and this link at least at one time had an image of what the plume looked like a couple of weeks ago or so.


As Lewis said the rough order of magnitude is one the order of 1 Bq per cubic meter. Most people do not have a clue as to what is dangerous and what is not dangerous. For that matter, lots of technical people don't know either.

The latest figure I seen for total event release of Cs-137 is 360,000 TBq. How much of that partitioned into the ocean, I don't know. Cesium metal has a sg of about 2, and cesium chloride has a sg of about 4. The total mass of Cs-137 released is about 110 kg. The large bags of concrete I believe are 50 kg. So we are talking about an object the size of 2 large cement bags.

If that was a single concentrated mass, it would be an awesome radiation hazard. But it isn't all in one place. Some fraction of that is measurable across something like 25-40% of the surface of the Pacific ocean. I have seen nothing about its distribution with depth. But as an aerial gamma survey result, that signal is only comping from about the top 1 meter of the ocean.

Telling people that the current level is such and such a fraction of values specified in regulations doesn't help. There are places where Brazil Nuts would be considered low level waste, if they weren't food. The regulations are an educated guess, and they completely ignore experience with places like Ramsar, in northern Iran.

We really don't know if 1 Bq/m^3 is bad, good, or indifferent. I believe studies are underway at WIPP (Carlsbad, New Mexico) and Gran Sasso (Italy) looking into radiation effects at very low levels of radiation. I think it would be nice if Snolab (bottom of the Creighton Mine, Sudbury, Canada) was also doing studies. As near as I can tell, there is no biology type stuff going on at Snolab.

But for people asking the question, can we clean the cesium-137 out of the Pacific Ocean, it is unlikely we have the technology to extract 100 kg of anything dissolved in that much water.

China confirms Jade Rabbit lunar rover has conked out

This post has been deleted by a moderator

JavaScript is everywhere. So are we all OK with that?


Why do I have NoScript?

I hate going to a site that comes up as a blank, having to go to the NoScript control, and find that page has javascript for 2 million different web sites on it. Or visiting newspaper sites that only display content with the help of javascript (then I often find w3m works just fine).

Adobe goes out of band to fix frightful Flash flaw


Non issue at Debian

This morning, there were updates for Windows, and if one runs the update-flashplugin-nonfree program on Debian, it does download and install something. But there are no notes in the security, users or flash mailing lists, and nothing in the bug reports.


I am in western Canada. I seen notes of this out of band update a couple of hours ago on another site. On a Windows box, I just updated Firefox, Thunderbird and plugins (maybe 20 minutes ago). The Firefox check for updates did not say there was an update for Flash available.

I also run Debian machines, and it will be a while before those filter through. But, I just did an apt-get update and checked the list of things that are updateable, and nothing flash is there yet.

Is modern life possible without a smartphone?


Nokia 2730 Classic

App? Calendar? I was just looking for something which if I got in an emergency on the highway, I could call for help on. The existing ringtone is annoying, but the idea of _paying_ to change it is not what I am looking for. Apps? If I want an application I will sit down and write one in Perl, C++, FORTRAN or whatever. Oh. my phone won't take applications in FORTRAN? That I wrote myself? Why would I want applications that someone else wrote, if I can't use applications I wrote?

Don't panic! Japan to send nuke fuel rod into MELTDOWN in Fukushima probe


Re: What worries me about this news is ...

Perhaps something in LA-13638 will look like data to you?


A Review of Criticality Accidents

Los Alamos National Laboratory

I've seen the 2000 Revision, perhaps there is a newer version available? This is a publically availabel document.

DARPA seeks game players to join bug-hunt


DARPA is just fishing for exploits for NSA.

Mexican Cobalt-60 robbers are DEAD MEN, say authorities


Re: I don't understand

Too slow on an edit:

I think I seen a report on this, that the source was found 1 mile from the truck (isolated area). Yet another report says there are 6 men at a local hospital complaining of radiation poisoning.

Some of what appears to be facts here, may be in error. It was a dumb thing to steal. If this slug of copper had of ended up in recycle and melted down (cobalt is a good alloying element for copper, at least for some applications), it would have been as annoying as the heat of iron or steel that got contaminated many years ago.


Re: I don't understand

Following up other reports on this, the source is about 3000 Curies of Co-60 as 40 grams of cobalt pellets in a copper cylinder (and copper is worth money, even a piece that is 10cm long by 3 cm in diameter). The field at one m is expected to be around 3000 REM/hour. At 1m distance unshielded, I am guessing LD-50 is 9 minutes.

The reason this cylinder has to be shipped in a truck, is the shipping container is heavy. I would imagine a few hundred pounds anyway.

MY EYES! Earth engulfed by BRIGHTEST EVER killer gamma-ray burst


Comparison to the Oh My God particle

Back on 19911015, a detector in the USA detected a cosmic ray particle (probably a proton, known as the Oh My God particle) with an energy of 3E8 TeV (about the same as a baseball thrown at 55 mph).

Bert and Ernie come in at about 1E3 TeV in energy. A proton has a mass of about 938 MeV, and a neutrino has a mass of about 0.23 eV.. The mass of a proton is about 4E9 more than the mass of a neutrino.

What ever gave rise to Bert and Ernie, was a much more energetic event than gave rise to the Oh My God particle. At least in my humble understanding as a materials scientist.

Magnetic slurry could deliver heatsink-as-a-service



As far as I know, the general name for this kind of fluid property is ferrohydrodynamics.

I've read of some neat applications in shock dampening, and in locking seals on doors.

Volvo: Need a new car battery? Replace the doors and roof


Fire, Scrapes and Corrosion

There are fire resistant matrices for composites, probably in large part driven by the aircraft industry. Cheap fire resistant matrices, probably not.

Some reinforcements can handle surface scratches, some can't. Your carbon fibre probably needs a thin surface layer of glass, just to handle incidental scrapes (or sanding in production). The extra layer of glass and matrix helps with the following.

Carbon fibre is noble to everything. Connections to metallic parts have to be electrically isolated. If panels have holes, the hole is probably oversized and then lined with epoxy to isolate the carbon fibres.


Biting the hand that feeds IT © 1998–2019