Wikipedia:Reference desk/Archives/Science/2007 May 6

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May 6

Uses of propynol

I live on rain water and had a water tampering and found high levels of sulfer and iron and also propynol at 20-30ppm in a 1lt jar, the water was acidic at 4.1. My question is does sulfrik acid contain propynol or what everyday things in our home would contain it? The police are of no use out here in the country and queensland health could only tell me thier findings, I suspect that sulfrik acid or concrett lime was placed inside the tank but I am having trouble finding full list of poisions in the product list. regards Kenpeds 03:41, 6 May 2007 (UTC)

From here;

"Propargyl alcohol has several major use areas. They include: reactant/chemical intermediate; pharmaceutical intermediate; agricultural chemical intermediate; corrosion inhibitor; solvent stabilizer; and polymer modifier (ACGIH, 1992; Kuney, 1994; Lewis, 1993; STN International, 1995b). Some examples of these uses and some specialty or potential new uses are presented in Table 2. In addition to the above uses, ACGIH (1993) and Lewis (1993) list "soil fumigant" as a use for propargyl alcohol. However, further literature and database searching failed to substantiate this use; and, responding to a request for information, Dr. Bill Burnham of EPA's Office of Pesticide Programs (OPP) reported that he was unable to locate any record of this chemical being used as a fumigant (Burnham, 1995)."

Propargyl alcohol is a synonym for propynol. There's a bit of a list of more synonyms here. Aaadddaaammm 04:57, 6 May 2007 (UTC)

This sounds rather serious, like somebody is trying to kill you. I'd set up cameras and motion detector lights to catch anyone who attempts to poison you again. StuRat 07:54, 6 May 2007 (UTC)

If someone is actually trying to kill you, don't play amateur detective. Seek professional assistance; see my comment below. TenOfAllTrades(talk) 18:21, 6 May 2007 (UTC)

The most immediate concern is to prevent this from happening again, which is why the lights and cameras are needed, this will discourage another poisoning, or at least make you aware when it happens, much like tamper-evident packaging. Also, if you can produce footage of a neighbor dumping something into your water supply, this would also likely justify a search warrant, and/or arrest, by the police. StuRat 05:08, 7 May 2007 (UTC)

I have all the set up camers and lights ect ect now and I know who the person was but proving it is different, I looked up the info you sent but has anyone got the making of what the propynol would have come in? I was thinking sulfurik acid becorse of the smell and fumes being a steem like vaper coming out of the tank. the tank was full 25,000 ltrs which run the whole house and the propynol was 20 to 30 ppm in a 1 ltr sample, so I am trying to work out how much was used and how long was I drinking and washing in it before the chem reaction happend? my 21 month old girl was very sick and my wife who just had surgery was also sick with bleeding internal. I am just concerned for the long time health my little girl. Kenpeds 08:43, 6 May 2007 (UTC)

Is there any possibility this could be acid rain ? That would be the case if you sometimes get rain falling through gases in the air released by industrial areas in major cities. StuRat 17:56, 6 May 2007 (UTC)

No. Acid rain does not contain propynol, and a pH of 4.1 is quite a bit too low for rain in rural Queensland. TenOfAllTrades(talk) 18:21, 6 May 2007 (UTC)

If you believe that you have been poisoned (deliberately or accidentally), your best bet is to see your physician (and your daughter's pediatrician). Be sure to bring a copy of the water testing report and the MSDS: link. Propynol is a common ingredient in corrosion inhibitors; it is widely used in industry. (Is it possible that there was some sort of accidental backflushing of a heating or cooling system liquid loop into your water? Such systems often contain corrosion inhibitors and various other nasty chemicals.)

For your reference, a single bottle containing 500 mL to 750 mL (a pint to a pint and a half) of propynol would be sufficient to produce a concentration of 20 to 30 ppm when uniformly mixed into 25 000 liters of water. It is not going to be an ingredient in sulfuric acid; the two chemicals are incompatible.

If you have reason to suspect that the contamination was deliberate, go to the police. Be prepared with the water testing report, MSDS for propynol, any medical reports on health problems you believe (or your physician believes) are related to possible propynol exposure, and a description of your water system's design. Your physician may also – with your permission – be willing to speak directly to the police. If you feel that the local police are not providing sufficient assistance, the Queensland Police Service website provides contact information for police headquarters as well as instructions for registering complaints.

While the suggestion above to include security lighting is not a bad idea from a general security standpoint, please don't assume that it's your responsibility to play Remington Steele and do all the investigation yourself. Your health is too important to leave to amateur detective work, and I am aghast that someone would suggest you deal with all this on your own. TenOfAllTrades(talk) 18:21, 6 May 2007 (UTC)

But before getting all worked up and starting a legal case, please first consider StuRat's idea about acid rain for one more moment. The few measurements of rain pH in rural tropical Australia have shown an average pH of 4.5, similar to Sydney levels, largely from natural vegetation sources of acidity [1]. A few values as low as 3.5 have been measured. The rain pH is highly seasonally dependent in tropical Australia, with the lowest pH values occurring in November at the beginning of the wet season. Thus a pH of 4.1 isn't extraordinary. Where in Queensland are you located, and when did you collect the water? Are you in the tropical region? Are you near or downwind from any human acidity source, such as the Mt. Isa smelter or some local power plant? As for the Propynol, note its use as a polymer modifier. Do you by any chance use a plastic tank? Or do you pipe the water through plastic tubing? If so, you might consider whether the propynol could have simply leached out of the plastic. Modifiers such as plasticizers are notorious for leaching or outgassing from plastics. The water presumably spends a lot of time sitting around in the tank and tubing. As for health effects of propynol, the US Environmental Protection Agency, based on very limited data, suggests a reference dose (a concentration estimated to yield "negligible" risk of health effects over a lifetime of exposure) of 2 micrograms per kg of body weight. That would correspond to only a few grams daily intake of your tank water. So you may want to fix the problem, if the concentration is reproducible. Before freaking out too much, however, note that the EPA reference value was based on an "uncertainty factor" (a factor they lower the reference value by when they don't have clear toxicity data, in the spirit of "better safe than sorry") of 8000. --mglg_(talk) 19:31, 6 May 2007 (UTC)

Hi all, no the tank is steel and qld health advised me that the leavals they found was to high to be in acid rain, I have found that Hydrochloric acid uses Propynol as a solvent and that might explain my eyes burning and blisters, also the rooten egg smell and viper like a steem coming from the tank??? as far as I can work out we where exposed for probely 3-4 days before I noticed the vipper from the tank. I live outside of Kilcoy 1hr from brisy and no factery or industral sights near us. The water was all 100% rain collected and the tank overfloed the day I found the affects. We are waiting on QLD police complaints to get back to us (public holiday today) as for my lighting and security camers all I can prove with them is what I capture at that time and it might only be simple tresspassing. At less I have gotten more ideas and info in the last 24hrs of this sight then all my questions and surching over the last 6 weeks on others. also everyone in my area are on tank water and no other complints or pollution have been reported. a house 2 doors down had a falling out with this man 3 years ago and the next day he found a white substance in his gutters testing was done on his water and the powder but nill to report as not anougth was found (same police still) and to him it is all just a pain in the ass. again thank you all for your help and ideas and keep them coming as the more info I have the more situations I can discount Kenpeds 21:57, 6 May 2007 (UTC)

Do you live close to a mine? Acid mine water from mines is incredibly acidic (pH values of -3.3 are common); only a few millilitres leaching into your water tank could reduce the pH to 4.5, and it's quite possible that propynol might be used in the mining industry, getting mixed in with the runoff. Laïka 11:44, 7 May 2007 (UTC)

With that acidity, if it is Hydrochloric acid, wont the zinc dissolve as well? Is this persons tank at risk of damage? (should the water be dumped and pay for more water rather that risk tank damage?).Polypipe Wrangler 22:14, 7 May 2007 (UTC)

I have found that Propynol is used in Hydrochloric acid so I must have assumed the wrong acid. The tank water has been dumped (25000ltrs) and the tank is getting replaced. New question is how much acid in that size tank I am taking a guess but would 10 ltrs be a ball park?? Kenpeds 02:30, 8 May 2007 (UTC)

Brainstorming specific examples for biology themes

Hi,

I'm trying to create a list of specific examples for the following themes in biology. I've got a couple of examples, it would be great if you could add to the list. Alex Ng 04:28, 6 May 2007 (UTC)

Energy Transfer Concept that energy flows from the sun into plants and into animals that eat them. Could look at energy currency in the cell (ATP)

Continuity and Change/Evolution

Relationship between Structure to Function

(Polymers) Cellulose: Beta-linking of glucose monomers results in firmness in plants

(Different organs/parts of organs and their functions)

Neuron:	Narrow shape (high SA/V ratio allows for quick change in Na/K ion concentration.
Node of Ranvier	increases speed of impulse transmission
Na/K Pump	maintains resting potential/restores resting potential
Villi:
Smaller microvilli	increases surface area for reabsorption
Single cell epithelial	faciliates reabsorption of nutrients
Alveoli	Massive, branching surface area allows for rapid oxygen uptake, carbon dioxide dumping.
Single cell epithelial	faciliates diffusion of oxygen and carbon dioxide
Moist membrane	faciliates diffusion of gases

PROTEINS. The structure of proteins dictates their function. Their 3D (tertiary) structure is dictated by their primary structure (amino acid sequence) which is dictated by the gene.

You could look at gross anatomy stuff, like um... long legs -> running, egg shell shape -> can't break it, gills -> breath underwarter, structure of the skin keeps stuff out (and in!)...

I would actually phrase it - lungs ->breath above water, since, you know, it's newer ;-) I'm not even gonna make a guess on where insect breathing apparatus fits in, though :-/ Someguy1221 05:26, 6 May 2007 (UTC)

Regulation/Homeostasis:

Blood glucose concentration (insulin lowers blood glucose levels by storing glucose as glycogen, glucagon increases blood glucose levels by doing the opposite) Maintaining proton gradient in mitochondria to keep ATPase making ATP. Glutathione reductase keeps glutathione reduced which keeps the right proteins disulfide-linked.

Interdependence in Nature

Examples of Relationships in Nature:

Relationship	Example
Neutralism (no affect on both)	A lizard resting on a tree root, neither ones really gives a damn.
Amensalism (one is negatively affected)	Bread mold Penicillium secrete penicillin that kills bacteria
Commensalism (one is positively affected)	Can't recall the general name, but plants that live on the bark of trees. The former gets a place to live, the latter is unaffected so long as the former isn't eating it.
Synnecrosis (both negatively affected)	One animal eating some other, poisonous animal.
Mutualism (both positively affected)	Cellulose digesting bacteria in cows steal food from the cow but help them digest grass.
Predation/Parasitism (one positive, one negative)	ANY PARASITE, but i like tapeworms

Re: Today's Feature Picture

"evidence of large bodies of liquid methane on Titan"

....according to the images taken by the Cassini orbiter.

My questions are:

1. Has methane been scientifically and absolutely identified?
2. What could be the source of such substance in a place like Titan?
3. Whence the carbon atom in methane????????????????
4. Has wave activity been recorded on the surface of the "75 large bodies of liquid" ??
5. What is NASA's "definitive evidence opf lakes fillled with methane" on Titan??

Thank you,

(email removed to prevent spam)

(Note: Question reformated to be easier to read, but words were not altered in any way by Sifaka ^talk)

3) Carbon is common on small bodies throughout the solar system. It also exists on larger bodies (Jupiter, Saturn, Uranus, Neptune, and the Sun), but is rare compared with the huge volumes of hydrogen and helium such bodies retain due to their higher gravitational attraction. StuRat 07:43, 6 May 2007 (UTC)

Our sub-article: Titan (moon)#Liquids on Titan says scientists have "definitive evidence of lakes filled with methane on Saturn's moon Titan" and provides this source. Rockpocket 07:50, 6 May 2007 (UTC)

As for (1), you can confirm what element something is just by looking at it - see emission spectrum / absorption spectrum. --h2g2bob (talk) 08:37, 6 May 2007 (UTC)

Exactly, there were a number of elements that were discovered this way, such as helium whose emission spectra was first identified in the Sun, hence the name. And if I'm not mistaken, this was prior to its discovery on Earth--VectorPotential^Talk 18:00, 6 May 2007 (UTC)

You are not mistaken. That's why the name is wrong: -ium is a metal suffix, but helium is a non-metal. Most elements are metals, I suppose, so it was a reasonable guess. Algebraist 10:32, 7 May 2007 (UTC)

Watts

Hi, I'm trying to work out how many watts a household device is, but dont have any specialist tools. I baselined the current house load by timing the electricity meter outside, then turned on the device and measured again.

The meter wheel measures in kwh (kilowatt-hour) where 266.6 turns = 1kwh

The initial baseline measurement was 43.3 seconds for a single turn.

After the device was turned on, it changed to 25.97 seconds for a single turn.

I'm figuring I should be able to do some math to figure out the wattage, but dont seem to be able to. Please help. E!

Let's see:

43.3 secs for a turn means 3600/43.3 or 83 turns per hour. That's 83/266.6 or 0.312 kw or 312 watts.

26 secs for a turn means 3600/26 or 138 turns per hour. That's 138/266.6 or 0.520 kw or 520 watts.

So, I get 208 watts. Anyone care to check my math ? StuRat 07:36, 6 May 2007 (UTC)

Much appreciated StuRat, the math looks good. I guess I just realised that a watt-hour and a watt are the same thing!! E!

They're not quite the same thing. If you leave a 100 watt light bulb on for an hour, that is 100 watt hours. If you leave the 100 watt light bulb on for a half hour, that is 50 watt hours. StuRat 08:23, 6 May 2007 (UTC)

1 watt-hour is equivalent to 3,600 joules. This is because 1 Watt is 1 joule per second. It already has time built in. Watt x Time = Energy (joules). So Kwh is just a measure of energy used. So, I dont think the math is right. Let's see if I can figure out what I mean.

43.3 secs for a turn means 3600 secs/43.3 secs per turn = 83 turns per hour. That's 83 turns per hour/266.6 turns per KWH or 0.312 kw-hours per hour. Ah, so the hours cancel and you are left with just kilowatts. So, the above math seems to be right. Mrdeath5493 14:07, 6 May 2007 (UTC)

Just to be thorough, this method of measurement seems very susceptible to error, but it looks to be the best you can do for now. Mrdeath5493 14:12, 6 May 2007 (UTC)

If you are going to do those kinds of tests, I'd make sure to unplug your refrigerator, freezer and turn off any electrical heating or air-conditioner (don't forget water heaters) for the duration of the test. Those things are on thermostats and may turn on and off at random during your experiment. Since they are all high wattage devices, that would drastically mess up your readings. But User:StuRats math seems solid to me. SteveBaker 14:20, 6 May 2007 (UTC)

Please look for a kh factor inscribed on the meter. It allows a direct conversion from seconds per revolution to watts. P.S. I doubt that anyone can accurately time revolutions to the hundredth of a second as claimed. Edison 05:21, 7 May 2007 (UTC)

Sure you can - count 100 revolutions - a stopwatch is accurate to a second - divide the answer by 100 - accuracy for one revolution is now 1/100th of a second. All it requires is patience. SteveBaker 23:40, 7 May 2007 (UTC)

I got some complexes in dealing with complex ions

Up to 5 minutes ago I used to believe that precipitates where covalent substances and now I discovered that there're neutral complex ions. I wanted to ask you how can you distinguish between neutral complex ions and covalent substances? Also in atmospheric oxidation eg Fe(OH)2 ---> Fe(OH)3 is it right to say that the oxidation was followed by a ligand substitution?

Oh also anybody know why negative mercury complex ions aren't called hydragates?Bastard Soap 15:20, 6 May 2007 (UTC)

Yup, something precipitates when it's not soluble...can be inorganic or organic and have ionic or covalent character, or be ionic with covalent ligands (or even covalent ions). Dissolve as much table salt as you can in a cup of boiling water, then cool it down, you'll get NaCl crystals. Regarding distinguishing a covalent from a net-neutral ionic, what's the form of the material (do you have some solid precipitate, trying to figure out whether it's ionic, or do you have a structural/chemical formula and trying to figure out what it is, etc)? Regarding naming, dunno. DMacks 19:58, 7 May 2007 (UTC)

My question was about how to figure between covalent dative compounds and simple covalent compoundsBastard Soap 10:50, 8 May 2007 (UTC)

Our dative bond page teaches that there's only a theoretical or academic difference between it an a covalent bond. Could you give some examples of pairs of things you'd like to distinguish? DMacks 13:26, 8 May 2007 (UTC)

So basically there are no experiments that prove dative bonding? Only theoretical inferences?Bastard Soap 13:07, 9 May 2007 (UTC)

According to the article, a dative bond is a covalent bond, the difference in names referring to a (slight) difference in how the bond formed in the first place. Algebraist 14:19, 9 May 2007 (UTC)

Yes, I knew that. What I want to know is if there are some experiments that prove dative bonding is actually taking place.Bastard Soap 18:17, 9 May 2007 (UTC)

Paper hydrolysis??

What happends to the bonds in a piece of paper when it is soaked in water?Bastard Soap 16:13, 6 May 2007 (UTC)

It's the same as the process of dissociation of salts and sugars in water. Water is capable of bonding to the components of the paper, and thus it is no longer so energetically stable for the paper to remain bound to itself. Someguy1221 17:32, 6 May 2007 (UTC)

So it's just partially dissolved? But I would imagine that some water molecules would get in between the structure of the paper as well, correct?Bastard Soap 18:19, 6 May 2007 (UTC)

Yes, and once they're there the paper would rather bind to the water than to itself. The only thing truly seperating this from the dissolution of table sugar is how huge the molecules are, and so you can think of the molecules as long strands bound together, that losen as water pulls them apart. But since they might be wrapped up in some odd fashion, it won't just desintegrate like sugar crystals. Someguy1221 02:10, 7 May 2007 (UTC)

False color satellite imaging

Why do most if not all photos taken by a satellite or any other unmanned vehicle in space are in false color? Why can't they send a true-color camera to take pictures? Examples being pictures of Mars and such. Never understood that. —The preceding unsigned comment was added by 99.244.236.45 (talk) 16:13, 6 May 2007 (UTC).

Many spacecraft do have "true-color" capability. However, they also captyre wavelengths beyond the spectrum visible to humans in hte near-infrared and ultraviolet wavelengths.To allow humans to guage certain realationships a scientist will map the recorded spectrum onto the visible spectrum.For instance: you cannot see the different temperatures of seawater, but hte infrared camera can detect the difference. We then map hotterto red and cooler to blue to show the differences.

The other reason to map colors is for aesthetics: a great many objects in the solar system are visually very boring, subtle shades of gray (for asteroids and the Moon) or brown (for Mars.) By remapping the colors, we can more easily see the subtle distinctions. -Arch dude 16:34, 6 May 2007 (UTC)

Additionally if you are taking pictures through a heavy atmosphere (i.e. Venus) then visual wavelength isn't useful at all. And there are plenty of true color pictures of Mars as well — Google Image search "mars surface" and you'll see a lot of them. --24.147.86.187 17:01, 6 May 2007 (UTC)

For most purposes, you need multispectral images in order to extract the maximum amount of information from the data. They often take photos at a range of different wavelengths - some visual some not. Most of the time the interesting data is available all across the spectrum - and if you are looking outside of the human visual range then you can pull more information out of the images using false color. But on some missions with a particular scientific goal the additional weight and power requirements for a visual spectrum camera may not be justified. Depends on what you are trying to find. SteveBaker 17:47, 6 May 2007 (UTC)

It would be very weird to *not* use imaging outside the human visual spectrum, since that's a totally arbitrary slice of the EM spectrum that happens to have evolved here on Earth where it's useful due to us being diurnal air-dwellers under a UV-blocking atmosphere. There's nothing special or more "natural" about 400 to 700 nm wavelengths. --TotoBaggins 18:32, 6 May 2007 (UTC)

There actually is. Earth's atmosphere is particuarly transparent in the 400-800 nm range. See Optical window for details. Out in space you are of course not bound by such contraints. Dr Zak 18:37, 6 May 2007 (UTC)

Yes, that's what I meant: we didn't evolve to use UV since it's so well blocked, and we didn't evolve to use infrared because we're diurnal, so it's just an accident of fate that the 400-700 nm range is "natural color" to us. --TotoBaggins 20:13, 6 May 2007 (UTC)

Well, not precisely an 'accident'. As omnivores - with a significant diet of fruit, we need color vision in order to be able to see when fruit is ripe - and when it's rotten. Carnivores don't need this ability - which is why (for example) cats and dogs don't have full color vision - it's more efficient not to have things you don't need. Similarly, we don't have UV or IR vision because we don't need it. However, honey bees can see in the ultraviolet and many carnivores (owls for example) can see into the near infra red so there is no particular reason why we couldn't have evolved to see outside of the 400-700nm range if there was a need for that. SteveBaker 05:09, 7 May 2007 (UTC)

Here's a few example links to browse on the topic of satellite hyperspectral, or multi-spectral, remote sensing. NASA's Terra (satellite) has several imaging devices on board. The MODIS sensor scans in 36 wavelength bands in the visible infrared range. The ASTER device scans in 14 different wavelengths in the visible range and infrared. These are not your ordinary RGB digital cameras! Meanwhile NASA's Aqua (satellite) has scanners like the AMSU, which scans 15 to 20 wavelengths, none in the visible light range (all microwave range I think). The QuickBird satellites, used for a lot of the imagery on Google Earth and Google Maps, are less data hungry, scanning in just the blue, green, red, and near-IR ranges. For other planets, there is the Mars Global Surveyor with its TES hyperspectral sensor.

Anyway, there's a few links to browse. One could spend a lifetime learning about this stuff, and some people do! Pfly 04:13, 7 May 2007 (UTC)

Earth's Spin

The previous question started me thinking. If you theoretically attached a giant rocket booster on the earth's crust to counter rotation (imagine that the booster wouldn't just break away with a piece of crust into space) and you blew up the moon to avoid it's annoying tides, the earth would never star spinning again?Bastard Soap 16:26, 6 May 2007 (UTC)

Well, one assumes that stopping the mantle from rotating wouldn't stop the vast liquid iron core from continuing to rotate. So when you turned off the motors, the friction between core and underside of mantle would gradually bring everything back spinning again. But I guess if you left the motors firing - adjusting the thrust to keep the earth from spinning, you'd eventually stop the core from spinning too. At that point, the earth would not start spinning again. SteveBaker 17:42, 6 May 2007 (UTC)

Being hit by a giant meteor might start the Earth spinning very slowly. StuRat 17:47, 6 May 2007 (UTC)

Many satellites are tidally locked to their gravitational big-neighbor the way the Moon is to the Earth. In the absence of spinning, perhaps the Earth would be lock onto the Sun, which would set it spinning at 1 revolution per year. --TotoBaggins 18:41, 6 May 2007 (UTC)

Also, that's going to take a *lot* of rocket fuel to stop the Earth from spinning. Maybe a mass-driver made with a supergun would be more environmentally sound? --TotoBaggins 18:45, 6 May 2007 (UTC)

A supergun uses fuel to propell a bullet which would impose a reaction of the earth, I'm not sure but I think in using rocket fuel you would have less losses of forcesBastard Soap 20:51, 6 May 2007 (UTC)

ahh heres a quick little experiment you can try for this. grab a regular egg spin it and then place your finger on the middle *gently* to stop the egg. release the egg and it will start spinning slowly again! its pretty awsome try it. User:Maverick423 Im in ur science steeling ur gravity 00:55, 7 May 2007 (UTC)

That's because the contents continue to spin, and quickly get the shell to spin again, too. StuRat 02:50, 7 May 2007 (UTC)

Which is the point of the experiment, and why Maverick suggested it... Skittle 19:59, 8 May 2007 (UTC)

Agreed, but it didn't seem so obvious that the original poster and all subsequent readers would necessarily understand without an explanation. StuRat 23:25, 9 May 2007 (UTC)

I don't think fuel is going to cut it (I can't find info on the energy content of rocket fuel, so I'm using petrol). According to my calculations, the earth has a rotational energy of about 2.6*10^29J. That's equivalent to about 7.4*10^21 litres of regular gasoline. So if we dug out all the earth's oceans to about 20km (about twice their current maximum depth), got rid of the water, and filled them with petrol, we would have about enough fuel for the task. If we could use it with 100% efficiency. </silly calculations> I think this plan is going to take UWTB. Algebraist 10:29, 7 May 2007 (UTC)

How about all the nuclear fuel in the world? (it was all just theoretical though mac)Bastard Soap 23:16, 7 May 2007 (UTC)

According to uranium, a kilo of uranium can produce 20TJ if you somehow completely fission it. So we're looking at about 10^17kg of uranium, i.e. 100 trillion tonnes. According to some random webpage, the earth's crust contains about 65 trillion tonnes. I'm too lazy to check up Thorium and suchlike possible fuels, so lets guess that they could make up the difference (my figure for the energy need is an overestimate anyway). So now all we need is a magic wand for extracting all uranium from the crust and putting it in our perfect reactors. Progress! (btw, who or what is mac?) Algebraist 14:17, 9 May 2007 (UTC)

You is mac. Then we can always cover up all the surface of the earth with a solar pannel Bastard Soap 18:49, 9 May 2007 (UTC)

Apnea

Are there any exercises which are specific to increase lung capacity and general respiratory pigment content in the body?Bastard Soap 16:30, 6 May 2007 (UTC)

Exercising at altitude will result in increased haemoglobin concentration in the blood. See Altitude sickness#Altitude acclimatisation for details of physiological adaptions (healthy and otherwise). David Ruben ^Talk 16:53, 6 May 2007 (UTC)

If a person has sleep apnea and is obese, then any exercise which helps them lose weight is likely to help. StuRat 17:45, 6 May 2007 (UTC)

Thanks but I was interested in particular exercises done at normal altitude which would have a particularly pronounced effect on lung capacity and respiratory pigment. I already knew about altitude aclimitasation and had thought about buying a hypoxic air generator but it's way too costly for a poor assed student such as me'self.Bastard Soap 17:55, 6 May 2007 (UTC)

I would guess that holding your breath would increase lung capacity, as would aerobic exercises, like jogging. StuRat 02:47, 7 May 2007 (UT

Blood doping by storing blood and adding it later works. So do certain hormones (EPO) that stimulant blood production. It's normally used to treat cancer or win the Tour de France. --Tbeatty 03:59, 7 May 2007 (UTC)

holding your breath helps alot. then stretch your chest by pushing it out while holding your breath. its what i do and it works for me. youll feel some pain but remember pain is weakness leaving the body =) User:Maverick423 Im in ur science steeling ur gravity 14:42, 7 May 2007 (UTC)

don't get anaemia.

And don't get an enema. (It's unlikely to help your lung capacity). StuRat 03:09, 9 May 2007 (UTC)

At least you will smell fresh inside :p Bastard Soap 12:36, 9 May 2007 (UTC)

42.2

I'm sure that the number 42.2 is important in atomic physics somehow, I just can't think where. Can anyone help me out? 128.243.220.42 19:37, 6 May 2007 (UTC) (User:Ollie)

I suspect 42.2 is just a pretentious version of 42, which is the most important number to the life, the universe, and everything. alteripse 19:55, 6 May 2007 (UTC)

Nah, this is proper physics I'm talking about ;) 128.243.220.42 19:57, 6 May 2007 (UTC)

42 (number), and [2] ? -- Consumed Crustacean (talk) 21:30, 6 May 2007 (UTC)

Could be one of the atomic weights of something? --h2g2bob (talk) 22:46, 6 May 2007 (UTC)

No, none of the above. I've now got home and had chance to look through my books and lecture notes, and I think I am making things up. All I can think is that I was getting mixed up with 54.4, the second ionisation energy of helium. Anyhow, many thanks for your suggestions. →Ollie (talk • contribs) 22:54, 6 May 2007 (UTC)

"Acrylic has an index of refraction of 1.49 for visible light4. Because the refractive index of

air is 1, total internal reflection occurs when the angle of the incident light ray is equal to or greater than 42.2°" (from here? —The preceding unsigned comment was added by Aaadddaaammm (talk • contribs) 02:19, 7 May 2007 (UTC).

Flower Identification

Can this flower be identified? J Are you green? 20:09, 6 May 2007 (UTC)

It looks like Foxglove.199.126.28.71 22:01, 6 May 2007 (UTC)

Sorry, 199.126, it is not foxglove. --mglg_(talk) 00:43, 7 May 2007 (UTC)

The flower does look like a foxglove to my untrained eye, but the stem isn't very foxglove-eque. Aaadddaaammm 02:27, 7 May 2007 (UTC)

Might it be a snapdragon? It's certainly a much better resemblance to the snapdragons we have in Australia, than the picture at that article. I can't say I've seen a snapdragon with this pinky-lilacy colour before - but then, IANAB (I am not a botanist) and IANMOAG (I am not much of a gardener). -- JackofOz 02:53, 7 May 2007 (UTC)\

Could it be a Texas Bluebonnet, or other type of Lupin? Bluebonnets are not always blue, just to nip that argument in the bud, so to speak. Where was the photograph taken? --LarryMac 14:58, 7 May 2007 (UTC)

The photograph was taken in the Mid-eastern US. However, it was in a garden, so I'm not so sure if that is helpful. J Are you green? 20:52, 7 May 2007 (UTC)

I do not think this is a lupin; the leaves grow alongside the flowers. J Are you green? 02:31, 8 May 2007 (UTC)

Dimensions

How come objects exist only in the 3rd dimension, and not anything higher? A response on my talk page or to let me know thus would be greatly apprieciated, thank you.199.126.28.71 21:54, 6 May 2007 (UTC)

Well, for a start, they don't, because there are at least four dimensions to space-time (although under general relativity you can't really say that there are three dimensions of space and one of time, although you can usually treat three of them as "spacelike" and one as "timelike"). Secondly, string theory generally suggests that there are at least six more, but they're curled up tightly so we don't notice them. (To visualise this, imagine you lived on a cylinder of infinite height but finite radius, so your world has two dimensions - along the height dimension and around the circumference. Now shrink the radius to something incredibly small, so it seems as though there is only one dimension left, although there may still be enough indirect evidence for you to discover the second dimension.) So it's not that objects only exist in four dimensions, but that we can only perceive four (and our perception of time is quite different to our perception of space). Recommended reading: Flatland: A Romance of Many Dimensions. Confusing Manifestation 22:54, 6 May 2007 (UTC)

(edit conflict)

That is just an observational fact: the world we see appears to have 3 spatial dimensions. There is no (known) fundamental reason for the number 3. In fact, according to some physical theories there are fundamental reasons for the number of spatial dimensions to be much larger, maybe 10 or 11. These theories sweep the extra dimensions under the rug (make them undetectable) through a trick called compactification. --mglg_(talk) 22:58, 6 May 2007 (UTC)

I thank you for trying to explain, but your explaination is confusing.199.126.28.71 23:55, 6 May 2007 (UTC)

We live in a three dimensional paradigm, nothing more. It doesn't make it real or true, it's just the best way we have found to explain it at the moment. Just like when we thought the world was flat, until someone found enough evidence to support a new model and contradict the current one. Fortunately if you see problems with the current three dimensional model at least you can discuss your ideas without the fear of being burned at the stake. Vespine 00:00, 7 May 2007 (UTC)

See Hypercube. We only perceive 3 dimensions. It is our limitation. There certainly could be 4 or more physical (i.e. not time) dimensions. We just don't perceive them. We lack the spatial imagination. I have see constructs of a "shadow" that a 4 dimensional object creates (it's 3 dimensional). Mathematically it can be described. A 4th physical dimension is orthogonal to the 3 physical dimensions we perceive. I believe string theory currently predicts at least 9 physical dimensions exclusing time. --Tbeatty 04:12, 7 May 2007 (UTC)

So, please explain WHY 'We just don't perceive them.'? Why is it our limitation? Thanks.199.126.28.71 05:53, 7 May 2007 (UTC)

I don't think that's known. We may perceive them in ways that we don't understand yet. For example, mass warps space into a fourth physical dimension. We perceive this as the earth orbiting the sun in a circle. But we are really moving in a straight line in four dimensions. we didn't realize this until the General Theory of relativity was published. The interesting thing is that is impossible (at least for me) to physically imagine 4 dimensions. I always have to move it to two dimensions warped into the third. For example, imagine a 2 dimensional plane wrapped around a sphere (i.e. the surface of the earth). It is easy to visualize moving in a straight line but travelling in a circle. It is really hard to take that to the 3 dimension case and imagine three dimensions warped into a 4th. Where does it warp too? This is where mathematics solves the problem. Mathematics exists where imagination fails. Imagining 4 lines that are all orthogonal to each other is impossible, but describing them mathematically is not. --Tbeatty 06:28, 7 May 2007 (UTC)

Well, were talking about spatial dimensions, not einsteinian dimensions. Could aliens see, per se, in 4 dimensions? If we had bigger brains would we or even, could we see in 4 dimensions?142.244.52.207 17:53, 8 May 2007 (UTC)

If you are interested in this stuff, you should try to get your hands on The Elegant Universe, which is a really interesting documentary on string theory and what not, and from what I recall, they did talk about the number of dimensions in the universe. - Akamad 12:07, 7 May 2007 (UTC)

Imagine you are a "point" - then you only have length and you can only move down a straight line. This line is your world. Then next imagine you are a set of points, or a line. Then you have length and breadth and you can only move around on a flat surface. Your world is flat :) Then imagine you are a box with length, breadth and height. Now your world is not flat anymore. You can jump and dive etc. YOU are this box. Your world is thus. Now imagine if you are a "superbox"' with an extra fourth dimension. To reach another superbox, you don't have to travel along a surface to reach another superbox. Your world has connection points between all superboxes that makes travel faster (or instantaneous depending on who you argue with) - so in the old world a box was a collection of planes, now a superbox is a collection of boxes. If this had to translate to our world, we would travel to other points of the world with ease. Sandman30s 13:54, 7 May 2007 (UTC)

Oh! I love answering this question - it's one of my favorites!

First - be totally clear about this - we don't see in three dimensions - for all purposes of this discussion, we may consider each of our retinas to be a 2 dimensional projection screen covered with teeny-tiny point light sensors. No different in principle from a TV camera. Each eye sees only a 2D image - our brains have learned from experience how to guess the 3D nature of the world from two 2D images which are oriented in slightly different directions and positioned a couple of centimeters apart. It's REALLY easy to fool this primitive mechanism (think of any of dozens of 3D optical illusions that fool us). So - we are already 'understanding' a world that has one more dimension than we can see!

So if the world was four dimensional (that is to say 'four spatial dimensions' - calling time a dimension is just wrong in this context), it wouldn't look any different than the 3D world - which in turn looks exactly the same as a 2D world. Our eyes are separated in 3D space - which helps with our limited 3D perception - if the world was 4D and our eyes were separated in that fourth dimension also - then perhaps we would notice that things were moving and had size in that 4th dimension too - but it wouldn't look much different from 3D.

What would a 4D world look like? Well, we already know - you can draw a 4D object using a computer and project it onto a 2D screen that matches EXACTLY how a 4D world would project onto your 2D retinas. If you draw even a 3D object on a computer - you have to make some decisions as to how to drop that extra dimension to get the image onto a 2D screen. We use the rules of perspective (or maybe we use orthographic representations) and tricks like 'depth cuing' (fog!) to indicate the third dimension in a way that completely fools our brains. We can easily model objects inside the computer in 4D,5D,6D or even 100 dimensions - the computer doesn't care much. But in the end, everything has to drop down into 2D to get it shoved through the limited capability of our eyes - and whatever decisions you make about how you drop those extra dimensions to get from 3D, 4D or 5D to 2D completely determines how 3D, 4D or 5D "looks".

If the world was 4D, and if we had a third eye that was separated from the other two in that 4th dimension - then our brains could probably evolve tricks to deal with it - just as we've managed to learn how to get some kind of 3D information from a pair of 2D eyeballs. But the more dimensions you lack information about, the more difficult the world would be to sort out - so with increasing dimensions, the world would get progressively more difficult to perceive - optical illusions would get more and more commonplace until we'd be unable to see anything unambiguously.

So - why doesn't the world have more dimensions? Maybe it does...but they'd have to be "small". What the heck is a "small dimension"?

String theory (which demands large numbers of dimensions that we clearly can't detect) suggests that the missing dimensions are very, very small. Imagine a world where one of our normal dimensions was curved around on itself. In a way, it is - the surface of the earth can be imagined as a 2D surface that's curved in the 3rd dimension. If you head off to the east and keep going - you eventually come back from the west to your starting point. If space were curved that way too - then a laser beam fired off to the East would shine back at you from the West. If you took a powerful telescope and pointed it off to the East - you'd be able to see the back of your own head. OK - so let's grab that 4th dimension and make it smaller. suppose the 4th dimension is like that - but the radius of the 4th dimension was (say) 10 meters instead of the radius of the earth. Looking off in the 4th dimension would reveal vast numbers of identical copies of everything - repeating every 10 meters forever. If the radius of the 4th dimension was just a bit bigger than your body - then looking off into the 4th dimension would reveal a very cramped world in that direction.

But string theory suggests that the 4th through 16th dimensions (or is it 15 or 26? Well, however many it is this week) are so tiny that they are VASTLY smaller than an atom - much, much smaller than an electron. So if you could see into the extra dimensions - all you'd see would be infinite numbers of copies of the 'normal' world - repeated at a spacing much much smaller than the smallest thing that science can detect. This is really tough to imagine - but not impossible. I think it would look exactly like the world actually looks - these extra dimensions simply wouldn't be noticable because looking in "that direction" would look no different.

Cool or what? SteveBaker 23:07, 7 May 2007 (UTC)

Consfusing... maybe? Well, would better discribe it??129.128.67.22 19:37, 8 May 2007 (UTC)

hudrochloric acid

if hydrochloric acid is added to a ph level of 6.5-7.0 water what would be the outcome?

propynol is used as a solvent for hydrochloric acid and my guess would be that the acid would quickly brack down in water leaving traces of propynol?? would it also rise the iron and sulfer leavels of the water?? regards Kenpeds 22:58, 6 May 2007 (UTC)

Umm .. hydrochloric acid is a solution of hydrogen chloride in water. If you add it to water you get a different concentration of hydrochloric acid. That's all.

You could get propynol if you started out with some. There's nothing about water and HCL which is going to synthesise it. --ColinFine 23:26, 6 May 2007 (UTC)

We do not do homework, but look at the article on pH, What do you think will happen to the pH? -Arch dude 09:23, 7 May 2007 (UTC)

Its not home work but if you care to look in yesterdays Propynol you could see why I was asking, I have lab results back but the police can not give me the answers.... Kenpeds 10:57, 7 May 2007 (UTC)

The concentration of the HCl and volume of water it is added to are important; very dilute hydrochloric, like that found in the stomach, would have a pH of 1.5-2, while fuming hydrochloric acid can have a pH of -1. Assuming completely neutral water (and using the values given in the previous question), adding 1 litre of conc. HCl (-1 pH) (about 1 bottlesworth) to 25,000 litres would give you a pH of 3.39; that's pretty strong, but not as strong as the hydrochloric acid in your stomach. Laïka 11:37, 7 May 2007 (UTC)

I apologize for the "homework" assumption. I saw a mis-spelled title, followed by an unsigned one-sentence question, followed by what I thought was an answering paragraph signed by you that appeared to be the sort of ellipitical response we usually give to homework questions. And now to work: if the miscreant added enough HCl to make the propynol noticable, then I suspect the pH was in fact altered at least for a period of time. A change in pH will in fact alter the overall chemistry of a holding tank by quite a bit, and this can in turn change the sulfur and iron chemistry. My house has a swimming pool,and I use a copper/silver system instead of chlorine to disinfect it. Occasionally, my maintaninence company will hire a new employee who does not know the difference. The newbie adds chlorine, and all hell breaks loose. The experts then come out and wrestle with the chemistry to get it back in balance. The basic problem: the chlorine causes the metals to form chlorides, which precipitate. Even when no chlorine is added, you can still get fairly major changes in the solubility of metal salts when the pH changes. If your miscreant added HCl, we should expect to see such changes. I suspect that this could explain the sulfer, also. -Arch dude 00:57, 8 May 2007 (UTC)