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Ozone

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About Ozone

  • Rank
    Meson

Profile Information

  • Location
    Crawfish Land
  • Interests
    Acquiring lab equipment, Photography, beer making
  • College Major/Degree
    PhD Candidate, Chemistry
  • Favorite Area of Science
    Carbohydrates
  • Occupation
    Research Chemist
  1. Ozone

    Co2

    Lookup the "critical point" or critical temperature. the phase transition you are worried about (liquid) only occurs at elevated pressure. At atmospheric pressure, CO2 will go straight to solid (and vice-versa) at -78 °C. In the cylinder, the CO2 is supercritical (in excess of the critical point) and it is a liquid. When opened to atmospheric pressure, it will go straight to solids (dry-ice flakes, for example). If dispensed into a sealed container (which can tolerate the pressure), you will have liquid. This liquid is used for extractions (of, say caffeine from coffee to mafe decaff--yark!), which is nice because opening to STP rapidly eliminates the solvent (dichloromethane was used before). So, also see "supercritical fluid extraction (SFE)". Cheers, O3
  2. From what I understand, they are at least considering the application of amorphous metal in golf club drivers! Whew! O3
  3. I have a neat demo kit from the University of Wisconsin (IIRC) which demonstrates what they call "liquid metal". It is, in fact, an alloy with a sufficient number of metals with sufficiently different atomic radii which, when supercooled, yields a product which is distincty non-crystalline. It is...amorphous. The demo consists of two polycarbonate tubes with stainless steel inserts/weights at one end (the bottom). Affixed to one of these inserts is a this (maybe 3mm) thick disk of the amorphous alloy. When a steel bearing is dropped into the tube from some distance, it bounces off of the steel insert several times and comes to rest. When the identical bearing is dropped onto the "liquid metal" it will continue to bounce for a minute or more. In a crystalline solid, there are cleavage planes which will slide (thus dispersing some of the incident kinetic energy at heat). These are sometimes called slip-planes. In the amorphous material, these slip-planes do not exist, so much less of the energy is dispersed. It is apparently also very tough. Some alloys cannot be cut with shears despite bearing a thickness similar to Al° foil. Check out: http://www.liquidmetal.com/technology/ Cool stuff! Cheers, O3
  4. Indeed! http://dictionary.reference.com/search?q=lemmings http://www.abc.net.au/science/k2/moments/s1081903.htm http://www.snopes.com/disney/films/lemmings.asp http://ask.yahoo.com/ask/20010725.html The list goes on. It surprises me that the same strategy has worked so well for Gore. Cheers, O3
  5. Well, at least it was not "K3wl". Cheers, O3
  6. LEMMINGS! http://en.wikipedia.org/wiki/Lemming Cheers, O3
  7. Fill a Dean-Stark trap with 4A molecular sieves. Distill off a few mL (the water will come over). Discard this fraction then swap out your still head for the trap and distill the rest of your DMSO directly on to the sieves. Pull your dried solvent from the bottom of the trap (stopcock)right before use. The only real worry is getting some into a heating mantle where it burns and smells *nice*. Take care, O3
  8. Less waste! Value-added for the CO2 spewing Cows of the Apocalypse! If anything, it should be viewed as a model of efficiency. Hamburgers and fuel, oh my! IIRC, they have been rendering turkey offal for sometime (in conjunction with a Butterball processing facility). The product was a "carboxylic oil" which could, no doubt, be esterified to yield a Greasle. I am not so sure, however, how close I would like to live to such a facility. To hell with tofurkey! Cheers, O3
  9. OK, animal fat (mostly C18) can be treated as plant fat when regarding the synthesis of methyl-biodiesel (methylstearate, etc.). 1. The fat should be rendered (melted) away from the water and protein (which you have there). 2. Why use H2SO4 (catalyst) to hydrolize ( not reduce) the triacylglycerides into glycerol and 3 equivalents of fatty acid when a direct transesterification with methanol would suffice? 2a. prepare a small amount of sodium methoxide (NaOMe). Add this to the methanol (which you have not referred to). This is reacted with the rendered fat directly. 3. Resins (sulfonated styrene-DVB) might be used for acid catalyzed esterification (which is two step, involving first, hydrolysis). 4. Experience? yes. 5. Economics are limited by the source of oil (a full 747 aircraft fueled with 20 % BD will cost ~ 80,000 USD in soybeans alone) energy expended in operation and value-added. Value-added will likely arise from the huge amount of glycerol which will be made when the process is carried out at industrial scale (for every 10 gallons of BD expect ~ 1 gallon or nasty, worthless crude glycerol). Cheers, O3
  10. Why would you want to do this? The energy put into (natural gas in the U.S.) making the ammonia (when coupled with the heat needed to split it) will exceed the energy recovered from combustion of the H2 so obtained. The most efficient routes (that I know of) include: 1. Recovery of H2 from reformer gas (low BTU gas) 2. Electrolysis At present, many facilities (including the carbon black plant nearby) reduce organic material to C and then flare the H2/CO (mostly H2, here) unless it feeds directly into a subsequent process (shift/carbonylation/reduction, etc.). They do this 24/7. It makes eerie, long purple plumes at night (they are invisible during the day). They might recover this if...It was cost effective--the hydrogen is there, but the energy needed to compress it is the killer. Electrolysis (of water to H2 and O2) is clean and efficient but the energy going to the electrodes has to come from somewhere. Likewise, this method suffers from the compression expense. The electrolytes needed to make it work are corrosive (salt or acid). PEMS might help (more efficient than an ICE) but are expensive and require heaters (and they can be heavy for the minimmum 3kW needed to, say, move a very small car at a useful speed whilst bearing modest cargo). At any rate, the scuttled ammonia facilities (due to the inability to profit over fuel) have recently been re-commissioned (as a result of skyrocketing fertilizer costs). This means that if you want to make H2, NH3 is not a cost-effective choice of feed. Cheers, O3
  11. Ozone

    Science News

    In addition to the massive quantity of science related email I receive from colleagues, I also regularly assay C&CEN, SCIAM, and Science, in that order. Discover is also a decent prologue (e.g. superficial reference). I also search several sites daily, including this one. I have found that a wealth of searchable references are available at any given time. There are also many blogs (pick your topic) that I peruse on my daily rounds. If you are interested, I also like to check out spaceweather.com. Cheers, O3
  12. "Re the results of tighter gun control (as opposed to total bans) - this does not need to be speculated about, since there are numerous nations which have done that. The results are very clear." No, they are not. How many lawful gun owners have been involved with a non-defensive homicide? How many criminals (who will have them anyway)? Human nature dictates that if killing need be done, killing will be done and it will be done using whatever is at hand (fork, soda straw, club, ashtray, bowling ball, etc.). Yesss. I suppose that stabbings and bludgeonings (general smiting) have gone up quite a bit. It would appear, however that this mode of homicide (suicide is rather difficult with a club) is unreliable and messy. O3
  13. Originally Posted by SkepticLance: "Conclusion - permitting guns in the home, and especially hand-guns will dramatically increase the loss of life due to suicide. " Actually, for suicide, a shotgun is a sure thing (rotten.com): Jul 2 1961 In the tile-covered foyer of his home in Ketchum, Idaho, novelist Ernest Hemingway commits suicide with his favorite shotgun. When the body was later found, "only his chin, mouth, and vestigial scraps of his cheeks were still connected to his body." Sounds effective, one shot too! It's good for the environment. Seriously. I suppose we should ban every other instrument that has been, can be used for or might possibly be employed to kill someone. That wouldn't leave much. Banning the guns makes sure of two things: 1. Only criminals will have them (they do not respect the laws, after all). 2. The lawmakers will face less resistance next time they wish to enrich themselves by infringing upon the rights of the "common" man (or woman, as the case may be). I hate to say it, but shooting is a fun and enjoyable past-time *and* is handy if someone decides to break into your house in the dark of night to kill your family (here, there is a new wave of "kill them then take their stuff" type of lazy and disrespectful criminals. Here, at least for now, it has been found that we can (and will) bear arms. Is it any wonder why shooting rampages frequently (nowadays) seem to occur in "gun-free" zones? Best, O3
  14. Remember to push the electrons. Following this convention, the proton will not "go" over to the chloride anion. Then consider which would be the stronger base. In this case, the alkoxide...(it will not likely exist under these conditions). The hydroxyl species is present in enormous excess; it is feasible that it will add to any carbocation that is formed, which will undoubtedly be the 2° moiety (look up the order of stability of carbocations). The Cl- will serve to regenerate your catalyst. (try to get your HCl back). Cheers, O3
  15. For critical drying and CO2 removal, eg. for conditioning GC carrier gas, etc. we usually use a layercake of LiOH and molecular sieves. YT is correct, the carbonate is a problem even in very fresh mixtures and a small peak can always be seen when using it to match eluent with anion exclusion chromatography. This is a plus, however, when you want to know the precise carbonate content so that you can correct titrant concentration. Another fine demonstration if to melt some lithium in a glass container over sand. Nice! Terms like "risk management" and "ambulance chasing lawyer" have largely ruined the fine art of scientific demonstrations. Collapsing cans, colored fire and small explosions tend to gain attention a bit more readily than "computer simulations". Pity. Cheers, O3
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