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July 24[edit]

Arctic flora?[edit]

Is rock samphire found anywhere in the Canadian Arctic, e.g. Nunavut?

Also, is there an English umbrella term or descriptor for plants like rock samphire and purple saxifrage, i.e. plants whose roots seem to grow through rock?

--Sonjaaa (talk) 04:29, 24 July 2008 (UTC)[reply]

Here[1] talks about survival food in parts of Canada including Nunavut. Part 2, found they are "seaside plants" (somewhere said related to carrots but can't find it again). Rock samphire includes culinary uses and it was known as "Crest Marine". Some common names could turn up here[2]. Julia Rossi (talk) 06:46, 24 July 2008 (UTC)[reply]

Sunglasses[edit]

When I wear my sunglasses, I notice two interesting effects. The first is that when I look at either the sky or my laptop screen, tipping my head to the side makes it brighter or darker. I know why that is--because my lenses are polarized, only waves at a certain angle get through. The second effect, though, is a mystery. Certain screens (calculators, parking meters, some cell phones, some iPods, etc.) appear all rainbow-y and the rear window of my car appears to be covered in dark splotches (not the other windows, though). I don't see how this could be a result of the polarization (though it may be and I'm just missing something), but I don't know what other property of my sunglasses could alter light in such strange ways. Explanations? Cherry Red Toenails (talk) 05:40, 24 July 2008 (UTC)[reply]

Read Polarized light#Polarization effects in everyday life. The effect you saw in your rear window should be present in all windows except the front windshield (polarized light reveals the stress pattern in tempered glass). Perhaps you're not looking at the proper angle. --Shaggorama (talk) 06:15, 24 July 2008 (UTC)[reply]

This is somewhat off the topic, but polarization + tipping your head while looking at your laptop and the sky, made me think of Haidinger's brush. J kasd 06:32, 24 July 2008 (UTC)[reply]

As for the screens; LCD screens use polarized light as part of how they work. See Liquid crystal display. --Random832 (contribs) 13:15, 24 July 2008 (UTC)[reply]

I know LCD screens are polarized, but why rainbows? It's like it's bending and separating the light instead of just filtering it. How does that happen? Cherry Red Toenails (talk) 06:51, 27 July 2008 (UTC)[reply]

BTW, have you noticed that if you look at a rainbow with polarized glasses at a certain angle it disappears? --Itub (talk) 17:30, 30 July 2008 (UTC)[reply]

Nano water[edit]

There is some product on the market called "nano water",claiming that it is made of "smaller water molecules" which can be more easily absorbed by human body. Well, aren't all molecules of some kind have excatly the same size? How come nano tech can change this without changing the chemical property of water?--218.103.243.132 (talk) 07:25, 24 July 2008 (UTC)[reply]

Bunk. Pure bunk. Don't even think of spending your hard-earned money even just to try it out. Have a read of this - more than you probably ever wanted to know about pseudoscientific water-related products. --Kurt Shaped Box (talk) 07:58, 24 July 2008 (UTC)[reply]

How would being more easily absorbed be beneficial anyhow? --Bowlhover (talk) 08:10, 24 July 2008 (UTC)[reply]

O₂ enriched water, tachion absorbing mouse pads, the pyramide effect and many other things are invented to earn money not to have an effect. If the water molecules would be 10% smaller than usual you would die very soon, because the folding of proteins is vitaly conected to hydrogen bridge bonds mediated by water molecules and the equilibrium constants for all reactions including this water would be significantly different. You have a similar effect if you drink heavy water upto a certain percentage no big problem, but than......--Stone (talk) 08:47, 24 July 2008 (UTC)[reply]

To be completely fair, from what I can find online, they're not saying they restructure or alter the molecules, but rather are [supposedly] breaking up "clusters" of molecules. --Random832 (contribs) 13:24, 24 July 2008 (UTC)[reply]

Nano water is one of the most shameful marketing idea. They just flush water pass through strong magnetic, neodymium type. The water will be ionized a little, which can reduce some scale problem in the hard water. Or some even believe the germs can be killed by that ions. And the ions in the water may make someone feel refreshment like some electric fan claimed the anion wind blow. But to say changing molecular shape of water is no science intelligent wording. And H2O is smallest unit of water which has been nano unit already. Always remind yourself one thing when talking about nano technology, most of them is related to solid matter, liquid may be emulsion only.......NINJAW —Preceding unsigned comment added by 124.120.205.180 (talk) 17:05, 24 July 2008 (UTC)[reply]

You may be interested in Penta Water. 81.132.215.251 (talk) 20:26, 24 July 2008 (UTC)[reply]

Can hydrogen peroxide destroy a man?[edit]

The other week someone told me of an industrial accident that one of their friends had witnessed a few years ago. Supposedly, a man at wherever this was meant to have happened was sprayed from head to toe with concentrated hydrogen peroxide from a leaky thingamajig. Within seconds, he 'simultaneously ignited, dissolved and exploded', leaving only his boots, a few unidentifiable chunks of flesh/bone and a pool of sizzling goop behind.

Tall tale, or a possible, genuine risk when handling H2O2? --Kurt Shaped Box (talk) 08:14, 24 July 2008 (UTC)[reply]

If you jump into a tank of H₂O₂ the organics are converted to CO₂ and the carbonate of the bones and all inorganic salts are oxidized but most of them are not very volatile, so you will have a layer of salts on the bttom of the container. This will take a little while to disolve the whole man, and the iron salts catalyse the destruction of H₂O₂. This is basically a good thing for a mythbusters test, because theoretically it is possible.--Stone (talk) 08:21, 24 July 2008 (UTC)[reply]

Thew youtube video Wasserstoffperoxid in Schweineblut gives a impression on how H₂O₂ reacts with the blood of a pig.--Stone (talk) 08:33, 24 July 2008 (UTC)[reply]

The hydrogen peroxide you buy in a drug store is only 3% concentration, and can still bubble when applied to a wound, so it's easy to see how 100% concentration would dissolve flesh entirely. StuRat (talk) 11:59, 24 July 2008 (UTC)[reply]

I'm skeptical about the speed of the process. Also don't forget that it's probably just the oxygen bubbling out of the H2O2 on the wound (catalyzed by substances on the wound) not the products of dissolving the body. Finally, expect bones to not react at all with H2O2. --Ayacop (talk) 14:13, 24 July 2008 (UTC)[reply]

Ayacop beat me to it. H2O2 sizzles on a wound because of the catalytic effect of hemoglobin, which is the same reason H2O2 is used in forensics to find blood. And the visible bubbles isn't any evidence of solvency as StuRat suggested, the H2O2 is just being broken down into water and oxygen gas. On unbroken skin, store concentration H2O2 does zilch. I can believe getting burns from the stuff though if a high concentration was sprayed on you: H2O2 is relatively unstable, so if a high concentration was sprayed out at a high pressure, O2 might rapidly evolve and if there was an ignition source nearby, could cause a fire. If the H2O2 was on someone, then the fire could be localized to the surface of their body. I vote for calling mythbusters. --Shaggorama (talk) 14:22, 24 July 2008 (UTC)[reply]

Not quite zilch (3% H2O2 on unbroken skin); if you get it on your skin and leave it there you're likely to get a little white spot, sort of a burn I guess you'd say, but it doesn't usually hurt. With 30% the burn looks the same, but does hurt. --Trovatore (talk) 17:58, 24 July 2008 (UTC)[reply]

I once soaked my feet in some 3% H₂0₂, and I only felt a slight tingle at first. Then a type of slow burn set in, and they were in pain for days afterwards. The stuff's a lot nastier than it would seem. StuRat (talk) 02:59, 25 July 2008 (UTC)[reply]

I agree with the above. Oxygen fires can be pretty nasty things. shoy (reactions) 16:05, 24 July 2008 (UTC)[reply]

Why would it leave his boots, but not his skin, which are both made of the same stuff? Also, anything you hear that your friend's friend saw is probably wrong. — DanielLC 15:08, 24 July 2008 (UTC)[reply]

Concentration of H2O2 in industrial application is about 35%only, there is a note that if more than 65%concentration will be dangerous for fire and explosion matter (but never found in industry). It also dosed with some kind of retarder to slow down its O2 releasing. To activate it, staffs in factory may adjust pH. U can see details of danger from website link below:

http://www.h2o2.com/intro/MSDS_35_Arkema.pdf

If someone got spraying of concentrated H2O2 (which available in the market) on him, the problems occured with him will be as below cautions:-

DANGER!CAUSES EYE BURNS. MAY CAUSE BLINDNESS.CAUSES SKIN BURNS.CAUSES RESPIRATORY TRACT BURNS.HARMFUL IF SWALLOWED.STRONG OXIDIZER.

Something, which may cause body dissolving, should be strong acid or base most likely...........NINJAW —Preceding unsigned comment added by 124.120.205.180 (talk) 16:49, 24 July 2008 (UTC)[reply]

Can someone search the MythBusters forum? When I get back to a computer with Flash I plan on submitting this. Those guys are geeky enough that they might like the Wikipedia angle. Plasticup ^T/C 17:51, 24 July 2008 (UTC)[reply]

ANNOUNCEMENT: I now have further clarification from my associate. The substance in question was apparently High test peroxide for military use and the accident occurred while the stuff was being transferred from a tanker. --Kurt Shaped Box (talk) 00:19, 25 July 2008 (UTC)[reply]

Helicopter: blades vs. turbine[edit]

Why do all helicopter (at least the ones that I have seen so far) have blades? Couldn"t we build a helicopter with a turbine in the middle? (and perhaps some other minor turbines for controlling the balance). —Preceding unsigned comment added by Mr.K. (talk • contribs) 10:32, 24 July 2008 (UTC)[reply]

Are you talking about blowing the air through the center of the helicopter instead of around the sides ? If so, that sounds like a less useful design in that the space for passengers and cargo would be reduced and in a weird hollow cylinder shape. You could also put two turbines on opposite sides, mounted on wings, to get something like the V-22 Osprey. StuRat (talk) 11:46, 24 July 2008 (UTC)[reply]

I think he means that blades vs turbine so to say V-22 Osprey vs Dornier Do 31. And he is right if you substitute the blades by a jet engine and make them turnable you get a Vertical Take-Off and Landing aircraft. I do not recognize any jet engine driven Helicopter which neglegted the posibility to turn the exhaust of the jet around to convert itself to a jet airplane.--Stone (talk) 12:22, 24 July 2008 (UTC)[reply]

Ultimately, the "why" is a matter of efficiency. As noted near the top of our helicopter article, "The lift from the rotor also allows the helicopter to hover... more efficiently than other forms of vertical takeoff and landing (VTOL) aircraft." The advantages posed by VTOL turbines do not offset this fundamental deficiency for the roles that helicopters fill. There was a related discussion about why we don't make similar aircraft designs some time ago. — Lomn 13:59, 24 July 2008 (UTC)[reply]

Lunar Landing Research Vehicle sounds like an example of what you're talking about. There are a number of problems with this arrangement, the big ones being safety (a helicopter can autorotate if the engine fails, while an LLRV can't) and fuel consumption (the LLRV can fly for ten minutes on a thousand pounds of fuel). --Carnildo (talk) 22:04, 24 July 2008 (UTC)[reply]

The efficiency problem is due to the size of the turbofans. They are naturally smaller than a big rotor, and a big rotor is more efficient. The turbofans do have advantages over rotors though. They have a higher thrust to weight ratio than a rotor of the same size. They can be vectored easily so they can turn the VTOL into a jet airplane which means much higher velocities compared to helicopters. Since the fans can be vectored, it also means greater manuverability than either a helicopter or airplane. Eliminates the exposed rotor which can accidentally strike something when landing. It means you can land in less open areas than a helicopter. You basically get the best of both airplanes and helicopters, and even some additional advantages depending on the design. But until there are some major innovatinos in energy sources, main rotors will be used because fuel efficiency is a priority. ScienceApe (talk) 19:34, 25 July 2008 (UTC)[reply]

Several dozen at least ?[edit]

how many atoms are there in the universe? —Preceding unsigned comment added by 218.186.12.11 (talk) 12:58, 24 July 2008 (UTC)[reply]

You may be interested in Observable_universe#Matter_content. -- Coneslayer (talk) 13:25, 24 July 2008 (UTC)[reply]

Hi. On the other hand, if you want to know how many elements there are in the universe, see periodic table, but note that only 94 are found to be naturally occuring, of which 10 occur only from radioactive decay, and 118 in total if you count the synthetic elements up to ununoctium, some of the higher elements have never been sucesfully produced, and more than that if the purely theoretical elements (beyond ununoctium) are counted. Thanks. ~A H 1^(TCU) 18:20, 24 July 2008 (UTC)[reply]

Whew AH, thanks indeed! ;-) -hydnjo talk 02:36, 25 July 2008 (UTC)[reply]

Seeing colours where there are none[edit]

Sometimes when I stare at objects which have a high degree of repetitiveness I will soon start to see a rainbow of sparkling colours. This quickly gives me a headache. The objects involved are almost always white. A good example would be a very fine white mesh net. Or a piece of paper with many alternating thin black on white stripes. Is there a name for this optical illusion? PvT (talk) 14:28, 24 July 2008 (UTC)[reply]

It may be related to Fechner color; that requires motion, but perhaps the natural motions of your head are enough. -- Coneslayer (talk) 14:30, 24 July 2008 (UTC)[reply]

I don't think fechner colors explains this, although i'm not sure what does. My guesses are more along the lines of lateral inhibition, in which case you should take a look at the grid illusion and mach bands articles. You might also want to read McCollough effect. Another idea I had is that you might be staring so fixedly as to effectively kill the capacity of your eyes' saccadic motion to copmensate for hyperpolarization of cone cells. --Shaggorama (talk) 15:47, 24 July 2008 (UTC)[reply]

Well one thing is for sure that figure in the top right of the McCollough effect article sure induces rainbow fireworks in my brain. It almost becomes wavelike and the aftereffect lasts quite long. PvT (talk) 19:52, 24 July 2008 (UTC)[reply]

Quasers[edit]

According to the latest developments in the field of Radioastronomy, Quasers have been discovered. But along with their discovery, a question arises in my mind. It is well-known that light emitted from them is a bit reddish in colour. There can be two possible reasons for this, namely:-\ 1)The Doppler Effect 2)The Einstein-Shift Principle But if the first concept is right, then the Quasers must be very far away. Hence they are not present in our locality. This proves 'Steady-State Theory' wrong. But if the second concept is correct, then light from Quasers appear to be reddish because of being released from very powerful gravitational fields. This on the other side proves the Steady-State Theory right. Which is the more probable cause of this event, the Doppler effect or the Einstein-Shift? —Preceding unsigned comment added by Asim Chatterjee (talk • contribs) 14:42, 24 July 2008 (UTC)[reply]

You may want to read quasar (note spelling). Their discovery is hardly a new development, and it is well-established by this point that their redshift is cosmological in origin. -- Coneslayer (talk) 14:52, 24 July 2008 (UTC)[reply]

The lack of quasars "locally" is because their formation is a less common phenomenon than other stellar processes. In any given region of space, the chance of finding a quasar is low. Superpositioned with the weak anthropic principle, it's even less likely to have intelligent-life-sustaining planets near them. I don't see how the absence of a quasar "in our locality" proves or disproves a steady-state universe hypothesis. Nimur (talk) 15:05, 24 July 2008 (UTC)[reply]

The OP is saying that the existence of a cosmological redshift is incompatible with a steady-state theory of the universe. This is true, but it's also old news, and nobody has believed in a steady-state universe for decades. But in response to your statement, note also that the peak of quasar activity was a long time ago, at redshift 2.5–3. They really are much less common in the modern era (which is synonymous with the local universe, due to the finite speed of light) than they used to be. -- Coneslayer (talk) 15:15, 24 July 2008 (UTC)[reply]

You'll have redshift in any expanding universe and you can have an expanding steady state universe, it just requires the constant creation of matter (to fill in the gaps, so to speak). The lack of nearby quasars could disprove steady state if it was due to quasars only existing in the early universe (when we look far away we see the universe as it was long ago) - the early universe being different from the current universe is the exact opposite of what steady state is all about. I'm not sure that is the case with quasars, though, although I'm sure it has been theorised at some point. --Tango (talk) 01:41, 25 July 2008 (UTC)[reply]

I took "steady state universe" to mean non-expanding, as in Einstein's universe. Apparently, that's not what it means—I apologize for mixing up the names of discredited theories. Anyway, as I wrote above, the quasar population absolutely shows time evolution; there were more of them, and they were more luminous, at earlier redshifts. This has been known for decades, and is not merely something that people have theorized about. My PhD thesis involved measuring the faint end of the QSO luminosity function at redshift 3, so this is a topic with which I have some familiarity. -- Coneslayer (talk) 02:10, 25 July 2008 (UTC)[reply]

Building projects[edit]

Are systems engineers involved in large scale building projects along with civil engineers? If so, what do they do in such projects? Clover345 (talk) 17:46, 24 July 2008 (UTC)[reply]

Ah another Systems engineering question.. The answer is yes, thought they may not call themselves/be called 'systems engineers'.

More likely is this in large/very large projects such as building the channel tunnel or making a airport terminal, but also in design of warehousing etc - in fact anywhere where the building/construction is built for a specific purpose and needs to be designed to operate efficiently when built and also when the project is complex and requires a lot of management to be done safely/on time/etc...

So they may be managers or designers or both.87.102.86.73 (talk) 18:02, 24 July 2008 (UTC)[reply]

I find it difficult to understand the concept of systems engineering. To me it seems simply to be project management, which is an already well established field. Many engineers claim they have never heard of such a field as systems engineering. Clover345 (talk) 18:47, 24 July 2008 (UTC)[reply]

No, project management (as typically intended) is quite distinct. Management is the high-level application of administrative skills to a given project. Systems engineering is better described as the high-level application of technical skills. That said, I find that it's often an appendage of another engineering discipline. SE on a large construction project is likely better filled by someone with a civil or industrial engineering background as opposed to an electrical or computer engineering background. SE on a highly electronic project would reverse the preference. In any event the systems engineer is likely to be treating many highly-technical portions of the program, themselves complex programs in their own right, as something approaching black boxes that must themselves be engineered to function together. — Lomn 19:18, 24 July 2008 (UTC)[reply]

Yes, and No. I tend to feel that 'systems engineering' is/was just a new buzzword. It does include project management, as well as ... well , basically everything else. (I bit like how 'bin men' or 'garbage collectors' are now called 'waste management logistics operatives'.) - now everyone is a systems engineer.

Oh and a systems engineer could also be a 'designer' or just a truck driver .. at the basic level getting your truck into a depot without blocking all deliveries for the rest of the day or running anyone over, or not demolishing one of the supporting structures of the delivery bay can be described as a 'successful systems engineering procedure'.. (I might be exaggerating)

You could describe 'systems engineering' as a field of bullshit, nevertheless it is being beginning to be taught at some levels as a concept - so I might as well be respectful.87.102.86.73 (talk) 21:17, 24 July 2008 (UTC)[reply]

The above wasn't intended to be overly negative, systems engineering does give a framework to systematically study the behavior of complex multi-part things, especially useful to spot potential problems that might (in a less systematic study) only become apparent 'in the field' - nevertheless it does tend to result in a hell of a lot of paperwork, eg Systems_engineering_process,System of systems,System of systems engineering,Enterprise systems engineering, Systems thinking etc etc. which makes many people sigh at the vast number of fields that now have 'system' inserted into their name..87.102.86.73 (talk) 11:52, 25 July 2008 (UTC)[reply]

Pre Bigbang Theory[edit]

In the Pre Bigbang theory, it has been said that at the beggining of the creation of the Universe,only one superforce was there, which later split up into two forms i.e the Electronuclear force and the Gravitational Interaction. But the Electronuclear force also split up to form Electroweak force and Strong Interaction, the former of which further fragmented to generate Electromagnetic Force and the Weak Interaction. But even the Theory of Relativity can not answer what was before 10^-43 seconds of creations of the Universe, as we then need to face the Unexplainable Singularity. It is also said by Stefen W. Hawking that Bigbang will be followed by Bigcrunch, which will be the contraction of the universe to an unimaginably dense and small ball of energy floating in space. But this process will start only when the value of Ά (the Relative Density of the Universe) exceeds 1. But at the end of this process of contraction, will all the forces meet up to form the Cosmic Superforce again? And if they combine, will the unification of the forces take place just before 10^-43 seconds of the Bigcrunch? —Preceding unsigned comment added by Asim Chatterjee (talk • contribs) 19:04, 24 July 2008 (UTC)[reply]

Yes. I mean, you are missing some details and assuming certain theories to be true, but if there is a Big Crunch the Universe will experience conditions similar to those 10^-43 seconds after the Big Bang. Plasticup ^T/C 19:26, 24 July 2008 (UTC)[reply]

As noted at our Big Bang article, generally-accepted scientific theory does not reach as far as the singularity, much less prior to it. No real consensus about a theory of everything and a resultant "superforce" exists. As for Stephen Hawking's putative support of a Big Crunch, I find little evidence -- the Big Crunch is thought unlikely based on present understanding, though virtually all cosmologists acknowledge it as a possibility. Given all of this, no meaningful answer can be given to your questions. We don't know (or have significant confidence in a guess) if your scenario will occur at all, much less whether it will play out as you've indicated.

ec with User:Plasticup -- As noted at Big Crunch, a crunch is not a "bang-in-reverse". Additionally, even if final conditions closely resemble the initial conditions of the Bang, we don't know if said initial conditions are what Asim suggests above. — Lomn 19:32, 24 July 2008 (UTC)[reply]

Apothecary symbols[edit]

I am reading some early 19th century apothecary recipes and am stuck on one of the symbols. There are two consecutive underlined letter a's followed by the sign for one ounce. What do the underlined a's stand for? —Preceding unsigned comment added by Wityoungbod (talk • contribs) 19:28, 24 July 2008 (UTC)[reply]

Could it be referring to an Apothecaries' system Ounce. The symbol doesn't look the same, but I suspect things weren't particularly standard at the time Nil Einne (talk) 21:16, 24 July 2008 (UTC)[reply]

An image would help - or a link to the book? - could those a's be two s instead ? meaning half?87.102.86.73 (talk) 11:00, 25 July 2008 (UTC)[reply]

Is there any drug that does this?[edit]

Is there any drug that produces a feeling anything like orgasm or 'sexual pleasure'? 199.133.19.254 (talk) 19:50, 24 July 2008 (UTC)[reply]

Normally only orgasm is the result of genital excitement. However, there are many drugs that produce euphoria, but taking them would probably be illegal as you can't go to the doctor and say you want medicine for "euphoria". Such illegal drugs include opiates, amphetamines, cocaine, methamphetamine and MDMA (see Euphoria_(emotion)). 81.132.215.251 (talk) 20:22, 24 July 2008 (UTC)[reply]

Sure. Some anti-depressants, at least, have been known to produce spontaneous orgasms in women. There may well be other drugs that have similar effects, though I can't think of any off the top of my head. Also note that numerous recreational -- both legal and illegal -- drugs have an effect of increasing sexual desire and/or making sex more pleasurable; while they don't really produce orgasms in themselves, a bit of physical stimulation can go a long way while under their influence. -- Captain Disdain (talk) 20:32, 24 July 2008 (UTC)[reply]

Aphrodisiacs. Surprisingly, despite the commercials, Viagra has no effect on the brain. --Bowlhover (talk) 20:36, 24 July 2008 (UTC)[reply]

Clomipramine#Side_effects. --Allen (talk) 21:53, 24 July 2008 (UTC)[reply]

You don't need drugs to do this. Self hypnosis can make you fell exactly the way you want to feel. But I'm not sure it can induce orgasm. Any way, the feeling you get is better than orgasm and lasts longer! —Preceding unsigned comment added by 79.76.239.220 (talk) 02:35, 25 July 2008 (UTC)[reply]

Wow Allen, good find! That's ::yawn:: crazy! --Shaggorama (talk) 20:11, 26 July 2008 (UTC)[reply]