Domain: elmhurst.edu
Stories and comments across the archive that link to elmhurst.edu.
Comments · 16
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What happens when methane combusts?
This is what happens. You get CO2 and water vapor.
Much better solution as you're outputting far less CO2 versus burning coal.
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Re:limitations of GC
Your points are generally correct, but your test for the non-GC-able prtion is not accurate. Compounds with boiling points well above the temperature of the column can be eluted from GC by having a high enough phase ratio, or a high enough flow, or waiting for a long enough time. A boiling point of 450 degrees C is reached at around C-30 , and I have seen presentations of GC of alkanes up to C-60, in I think I have heard about GC of up to C-100. In that range, it becomes more a question of thermal stability, but anything present in oil will have experienced prolonged periods of elevated temperature, so nothing particularly thermally labile should be left. However, this does not go for the degradation products.
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Can some humans digest fiber better than others?
Good point, AC! Certainly cows and termites can break down fiber with different gut bacteria (and different gut architecture).
http://www.elmhurst.edu/~chm/vchembook/547cellulose.html
"Animals such as cows, horses, sheep, goats, and termites have symbiotic bacteria in the intestinal tract. These symbiotic bacteria possess the necessary enzymes to digest cellulose in the GI tract. They have the required enzymes for the breakdown or hydrolysis of the cellulose; the animals do not, not even termites, have the correct enzymes. No vertebrate can digest cellulose directly."That said, somehow I doubt humans could do it because we are not multi-stomached ruminants, but it would be great to see more science studies about it. Maybe you will be proven right and some humans with the right bacteria can do it better than other?
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Re:The meaning of random
No, the solubility of carbon dioxide decreases as the temperature of water increases. This is generally the case with gasses. On the other hand, the oceans have not been saturated with carbon dioxide... yet.
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Re:re Increase or decline?
Allow me to extensively quote John Cook (http://www.skepticalscience.com/What-do-the-hacked-CRU-emails-tell-us.html), as he is closer to the topic than I am.
What do the suggestive "tricks" and "hiding the decline" mean? Is this evidence of a nefarious climate conspiracy? "Mike's Nature trick" refers to the paper Global-scale temperature patterns and climate forcing over the past six centuries (Mann 1998 http://www.elmhurst.edu/~richs/EC/FYS/Mannetal.OriginalPaper.pdf), published in Nature by lead author Michael Mann. The "trick" is the technique of plotting recent instrumental data along with the reconstructed data. This places recent global warming trends in the context of temperature changes over longer time scales.
The "decline" refers to the "divergence problem". This is where tree ring proxies diverge from modern instrumental temperature records after 1960. The divergence problem is discussed as early as 1998, suggesting a change in the sensitivity of tree growth to temperature in recent decades (Briffa 1998 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1692171/pdf/43XA8LK6PCMVMH9H_353_65.pdf). It is also examined more recently in Wilmking 2008 ( http://www.clim-past-discuss.net/4/741/2008/cpd-4-741-2008.pdf ) which explores techniques in eliminating the divergence problem. So when you look at Phil Jone's email in the context of the science discussed, it is not the schemings of a climate conspiracy but technical discussions of data handling techniques available in the peer reviewed literature.
In the skeptic blogosphere, there is a disproportionate preoccupation with one small aspect of climate science - proxy record reconstructions of past climate (or even worse, ad hominem attacks on the scientists who perform these proxy reconstructions). This serves to distract from the physical realities currently being observed. Humans are raising CO2 levels ( http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm ). We're observing an enhanced greenhouse effect ( http://www.skepticalscience.com/empirical-evidence-for-co2-enhanced-greenhouse-effect.htm ). The planet is still accumulating heat ( http://www.skepticalscience.com/global-cooling.htm ). What are the consequences of our climate's energy imbalance? Sea levels rise is accelerating ( http://www.skepticalscience.com/sea-level-rise.htm ). Greenland ice loss is accelerating ( http://www.skepticalscience.com/greenland-cooling-gaining-ice.htm ). Arctic ice loss is accelerating ( http://www.skepticalscience.com/Arctic-sea-ice-melt-natural-or-man-made.htm ). Globally, glacier ice loss is accelerating ( http://www.skepticalscience.com/himalayan-glaciers-growing.htm ). Antarctic ice loss is accelerating ( http://www.skepticalscience.com/antarctica-gaining-ice.htm ).
When you read through the many global warming skeptic arguments ( http://www.skepticalscience.com/argument.php ), a pattern emerges. Each skeptic argument misleads by focusing on one small piece of the puzzle while ignoring the broader picture. To focus on a few suggestive emails while ignoring the wealth of empirical evidence for
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string analogues
"The point is that we have two different kinds of systems capturing the same kind of physics," says string theorist Clifford Johnson
Back in the day it was commonplace to construct analogs of mechanical systems, for instance, using electronic components. If the differential equations describing the two systems are similar, so will their solutions be.
That the topic is string theory is also reminiscent of how soap works. Half of a soap molecule is soluble in water, the other half insoluble - thus bridging between wet and oily substances. Very yin and yang.
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Re:This picture puts all in perspective
Considering that a gallon of gold is about 1/20th the cost of scorpion venom, I'm surprised we don't start wearing little capsules of the stuff around our necks.
Your comment got me thinking so I did some quick calculations in case anyone is interested...
The price of gold right now is $800/troy oz. and a troy ounce is 31.1 grams
Therefore a gallon of gold by weight would be.
( ( 128 * 28.35 ) / 31.1 ) * 800 = $93345.33
A gallon of gold by volume is another story.
A gallon is 3,785.4 cc and the density of gold is 19.3 g/ml.
Therefore a gallon of gold by volume is...
( ( 3785.4 * 19.3 ) / 31.1 ) * 800 = $1,879,311.12
Also, this gallon of gold would weigh 161 lbs. Someone please correct me if I made any mistakes. -
Re:Oy vey gevault.You're right in implying there's an element of deception in the global warming "debate". People mistake correlation for causation all the time, often because they're told to and they're unable to think for themselves.
It is true that there is deception in the "debate." Calling it a debate is the deception.
Many mistake global warming correlating with higher CO2 with a global warming caused by CO2. Having perused material on the matter, and discussed it with colleagues who track this, there is no evidence to suggest that higher CO2 causes the global warming we are seeing today.
Correlation does not imply causation. Correlation does, however, suggest that something is going on, and offers a good place to start looking. Correlation combined with a good hypothesis backed up by experimentation, does give you a reason to suspect causation.
CO2 is a greenhouse gas, that is *not* debatable, simple physics tells you that (water vapor is to, but we aren't anthropormorphically changing its level like we are with CO2).
Worse is that the lack of balanced scientific debate on the topic, and the number of lemmings who blindingly need to point a finger without any actual evidence, is undermining the ability to observe and make rational opinions.
I have an idea, why don't we let the scientists work on it, and come to a consensus? That way we don't have ignorant (in the non pedantic connotation) slashdotters bitching about a lack of "balance." Oh, right, that's been done.
However, it's Slashdot. It's a populous opinion. Don't take it personal when the lemmings come and mod you down for, God forbid, positing something contrary to the convenience of their finger-pointing! :)
Not sure what that wonderful game has to do with this, but I'm all for early 90's references. Posting contrary ideas is all fine and good, but when the topic is a scientifically determinable question, and you are on the incorrect side, you're gonna catch shit. Arguing that evolution is wrong, or that gravity is only a 'theory' will do the same thing.
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Re:Global Hubris
Nor should you. Look at the second graph down. CO2 is almost linearly more soluble in a colder liquid than a warmer one. It has nothing to do with the absolutely minute volumetric changes in a liquid from those relatively minor temperature changes. Carbon Dioxides actually DOES "magically" leak OUT of beer as it gets warmer, because it's less able to stay dissolved.
Looks like they let some idiots have mod points again. I'd have modded it down, but no one would have known why. C'est la vie. -
Re:Three Points
If the ice on top of Greenland melted, the Earth's oceans would rise 6 to 7 meters
Oh dear, I read that too, in some pro-GW article in the Guardian. And if you do the math, or even estimate the result, you will realise it is pure bull.
The increase in volume of ice over the same amount of water is about 9%.
Approximate area of all oceans 105,000,000 square km
Area of ice in Greenland is is 1,755,637 square km
So average depth of ice on Greenland needed raise global sea level by 6 meters (without taking the increase in sea area into account):
105,000,000 / 1,755,637 * 0.006 * 1.09 = 266,953,106 km
Do I think we should reduce polution and find a way to stop using fossil fuels? Hell yeah.
Do I think that "the sky is falling!" eco-nutjobs are prepared to lie to promote their cause, and in the process unwittingly bring the whole eco movement into disrepute? Damn straight. -
Water-repellant ?
Sure, it's water repellant, but doesn't mineral-oil float on top of water, thus ruining the MB you have on the bottom of the acquarium
... ?
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Water-repellant ?
Sure, it's water repellant, but doesn't mineral-oil float on top of water, thus ruining the MB you have on the bottom of the acquarium
... ?
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Re:Bad "science"
Maybe you shouldn't jump to conclusions on the validity of the science on the basis of an NYT article.
One of the many ways of studying past climate patterns is by looking at ice cores.
We have pretty good data on long term climate patterns in cold places. Some links here:
http://www.elmhurst.edu/~chm/vchembook/globalwarmA .html
http://www.secretsoftheice.org/icecore/warming.htm l
http://www.brighton73.freeserve.co.uk/gw/paleo/pal eoclimate.htm -
Mod parent (-1: needs a college micro course)What a day to be without mod points.
Please do a quick Google for antibiotic families and modes of action. You will find pages like this and this.
Penicillin and derivitaves are still prescribed, but virtually every bug in the world (+ dog) is resistent to them.
One evening of watching the Discovery channel does not a B.S. in Microbiology confer.
The "natural" antibiotics to which you refer are still being found by the dozens. The problems are not (primarily) with patents. You have to:
You have to find an organism that has some antibiotic activity. Not as easy as you might thing. Searches go on CONSTANTLY, and the major drug companies grab soil samples from everywhere they can to test for organisms in the soil that exhibit unknown antibiotic properties.
You've spent several years and have found a likely candidate. Now you have to test the snot out of it. How does it do what it does? Is it a cell wall synthesis inhibitor? Does it go after 23S ribosomes? How about side effects? After all, bleach is one of the best antibiotics in the world. It's used for disinfection in BSL3 and BSL 4 microbiology labs. However, it wouldn't do you much good if you were to drink it, either. Drug interactions? If it kills someone that is taking a common drug (or worse, an uncommon drug), you're still in trouble.
Now, you have to start the FDA certification process. Do you think the FDA reimburses you for the millions you've spent to this point if things go bad? Nope. Do you think they're even going to reimburse you for the millions you're going to spend in clinical trials? Not likely. Remember Martha Stewart and IMClone? The bottom fell out of ImClone because they'd sunk a good chunk of their cash into a drug that was not going to be approved (granted, IIRC it was a cancer drug and not an antibiotic, but the principle applies).
Yes, pharmaceutical companies are businesses. They are for-profit. But it is not so much corporate greed that causes some of the outrageous drug prices as it is them having to pay for the research costs involved with the 99 drugs that didn't make it to market with the money made from the one drug that did.
Please do some research before making statements like the ones you've made.
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Re:How fast is too fast? (Warning, physics ahead)
I'm sorry, that graph may have been misleading since it gave concentration as p(negative log). Here is clearer graph http://www.elmhurst.edu/~chm/vchembook/images2/17
4 solublegas.gif. -
Re:Not a chemist1) fructose is a "left-handed" molecule -- your bodie's enzymes are "right-handed".
2) fructose collapses into a 5-membered ring structure, with an attached methanol group. the sugars which your body likes have a 6-membered ring structure (glucose, sucrose, &c.) which have an ether bond, rather than a c-c bond closing the ring.
now, I am not a bio-chemist (IANABC?), but I don't think that the (normal) human body actually makes use of fructose (krebb's cycle, &alia) for ATP production, at all... however...
fructose is not the only (or even, necessarily, the *primary*) sugar which you will find in fruits. beet sugar, cain sugar, &c. are glucose based.
for a brief summary of carbohydrates, you could check out Di-poly-carbohydrates