I've liked these guys for years. I'm afraid I've screwed-up royally by not seeing them. Now it's too late. They're too big.
Sunday, January 29, 2012
El Camino Real
I've liked these guys for years. I'm afraid I've screwed-up royally by not seeing them. Now it's too late. They're too big.
Saturday, January 28, 2012
Friday, January 27, 2012
Wednesday, January 25, 2012
Element Swapping
Chlorophyll |
Sometimes, one element can substitute for another. Chlorophyll contains a central Mg2+ ion surrounded by a porphyrin (above) yet runs at about 70 % efficiency when a Zn2+ ion replaces a magnesium cation. Mg2+ and Zn2+ resemble each other and since the cation isn't doing anything exclusive to magnesium, perhaps this is not surprising. The simple role of native magnesium in chlorophyll is to polarize the electrons in the surrounding molecular scaffold.
Hollywood and Washington D.C. are like the porphyrin scaffold in chlorophyll. A more or less permanent structure surrounds a central star and or an elected official. Most any organizational structure is like that. The surrounding scaffold comprises pundits, critics, enablers, staff, etc., and nurtures but eventually disposes of central atoms for the next one.
Monday, January 23, 2012
Bromine Has A Hangover
Most of the world's bromide is dissolved in the sea, but chloride still outnumbers it by about 500 to 1. Originally dubbed "muride" from the Latin word muria meaning brine,* bromide was renamed after bromos which means stench (of male goats) in Greek.
Elemental bromine is a nasty red liquid (bromine and mercury are the only two liquid elements at ambient temperature and pressure). An electron short of an octet and tranquil stability (as bromide), the fuming element can still suck the electron out of many a juicy nucleophile, as I wrote back here. But its power for doing so is less than chlorine's and much less so than fluorine's power. Bromine can still "oxidize" iodide back to iodine, though.
Bromine's usefulness is diminishing. Its greatest ex-use was as ethylene dibromide--an additive for leaded gasoline (it scavenged the lead). Film photography used to rely on silver bromide, but digital photography is killing off that use. Bromide used to be a mild sedative and hangover cure--until it was outlawed for over-the-counter sales around 1995. The main use for the element today is for making fire retardants--as organobromides which are ubiquitous in electronic products.
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*Cf. Muriatic acid, the original name for hydrochloric acid: link
Elemental bromine is a nasty red liquid (bromine and mercury are the only two liquid elements at ambient temperature and pressure). An electron short of an octet and tranquil stability (as bromide), the fuming element can still suck the electron out of many a juicy nucleophile, as I wrote back here. But its power for doing so is less than chlorine's and much less so than fluorine's power. Bromine can still "oxidize" iodide back to iodine, though.
Bromine's usefulness is diminishing. Its greatest ex-use was as ethylene dibromide--an additive for leaded gasoline (it scavenged the lead). Film photography used to rely on silver bromide, but digital photography is killing off that use. Bromide used to be a mild sedative and hangover cure--until it was outlawed for over-the-counter sales around 1995. The main use for the element today is for making fire retardants--as organobromides which are ubiquitous in electronic products.
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*Cf. Muriatic acid, the original name for hydrochloric acid: link
Saturday, January 21, 2012
Conversations with Henry
[after a particularly tense group meeting at the start-up]
Me: Man, he about took my head off in there. I had to push back like that.
Henry: Well, don't take it too personally. He knows what he's doing. It's for the better.
Me: How so? He made me feel like crap.
Henry: When I was a grad student over at Berkeley, grown men--professors--used to curse and shout at each other over their ideas. It was a downright mean and nasty to watch.
Me: Do you think some of that had do to G. N. Lewis? He was still in charge then wasn't he?
Henry: Lewis was like that, yeah. The thing is that after all that screaming and yelling over what they thought were so very important ideas--the same guys would always simmer down and go out for beers afterwards.
Me: Man, he about took my head off in there. I had to push back like that.
Henry: Well, don't take it too personally. He knows what he's doing. It's for the better.
Me: How so? He made me feel like crap.
Henry: When I was a grad student over at Berkeley, grown men--professors--used to curse and shout at each other over their ideas. It was a downright mean and nasty to watch.
Me: Do you think some of that had do to G. N. Lewis? He was still in charge then wasn't he?
Henry: Lewis was like that, yeah. The thing is that after all that screaming and yelling over what they thought were so very important ideas--the same guys would always simmer down and go out for beers afterwards.
Bromine swings both ways when coupling with double bonds
Here's a little chemical example of my favorite dictum: polarization followed by attack, followed by depolarization.
In certain solvents, molecular bromine, Br2, cracks apart into plus and minus ions: bromide and bromonium (note the cool use of the "ium" suffix for the positively charged ion):
Now Br2 will add to ethylene to make ethylene dibromide, a useful pesticide, but the bromine and ethylene can't simply couple because it's forbidden. Instead, bromonium ion approaches ethylene, sucking at and polarizing her most available electrons (recall I deduced that ethylene was female here). Bromonium's negatively charged doppelgänger (umpolung!) then backside attacks the polarized ethylene, after which her electrons collapse into bromonium's clutches and the partners relax. Here's a visual:
In certain solvents, molecular bromine, Br2, cracks apart into plus and minus ions: bromide and bromonium (note the cool use of the "ium" suffix for the positively charged ion):
Br—Br —> Br- + Br+
Now Br2 will add to ethylene to make ethylene dibromide, a useful pesticide, but the bromine and ethylene can't simply couple because it's forbidden. Instead, bromonium ion approaches ethylene, sucking at and polarizing her most available electrons (recall I deduced that ethylene was female here). Bromonium's negatively charged doppelgänger (umpolung!) then backside attacks the polarized ethylene, after which her electrons collapse into bromonium's clutches and the partners relax. Here's a visual:
Labels:
Bromine,
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hypothesis,
umpolung
Michigan is still well endowed with bromides
Herbert Henry Dow (1866-1930) |
I just ordered an old biography about Herbert H. Dow. I don't own a kindle, so I tend to collect books. I have lots of older books too.
Herbert Dow based his eponymous company in Midland, Michigan because he found lots of bromide ion in the water there. I learned that when I visited there--years ago--to help a company evaluate some technology they were buying from Dow.
Dow originally invented a process for producing bromine from bromide and the story of him beating the Germans at their own game fascinates me. I want to read more.
Wednesday, January 18, 2012
Bastards of Young
The ones who love us best are the ones we'll lay to restH/T: bill of so quoted
And visit their graves on holidays at best
The ones who love us least are the ones we'll die to please
If it's any consolation, I don't begin to understand them...
Tuesday, January 17, 2012
What Is The World's Smelliest Chemical?
Wikipedia corrals some of the suspects here: link I thought I'd put their mugshots up here. Please vote for your favorite in the comments or suggest your own "worst."
(1) Spermidine, the essence of "funky spunk."
Spermidine is related to aptly-named cadaverine and putrescine.
(2) Trimethylamine, the essence of "fish taco:"
(3) Butyric Acid, the essence of vomit:
(4) Skatole, an indole & the essence of poop:
(5) Mercaptans--methyl and butyl thiols--the essence of skunk:
(6) Hydrogen sulfide, H2S, the essence of rotten eggs and bad farts:
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Runner's up which did not make Wiki's list:
(a) Cacodyl, named from the Greek, meaning "evil-smelling."
(b) Bromine, from Greek βρῶμος, brómos, meaning "stench (of he-goats)"
(c) Cyclohexane thiol: This is technically covered under (5), but to my nose smells like the essence of armpit B.O.
(1) Spermidine, the essence of "funky spunk."
Spermidine is related to aptly-named cadaverine and putrescine.
(2) Trimethylamine, the essence of "fish taco:"
(3) Butyric Acid, the essence of vomit:
(4) Skatole, an indole & the essence of poop:
(5) Mercaptans--methyl and butyl thiols--the essence of skunk:
(6) Hydrogen sulfide, H2S, the essence of rotten eggs and bad farts:
_____________________
Runner's up which did not make Wiki's list:
(a) Cacodyl, named from the Greek, meaning "evil-smelling."
(b) Bromine, from Greek βρῶμος, brómos, meaning "stench (of he-goats)"
(c) Cyclohexane thiol: This is technically covered under (5), but to my nose smells like the essence of armpit B.O.
Monday, January 16, 2012
Saturday, January 14, 2012
Conversations with Henry about another Henry
Henry: Henry Moseley really convinced everyone that atomic numbers were real. Atomic number was just Bohr's theory until Henry Moseley proved it true.
Me: Moseley's Law?
Henry: Yes. A theory becomes a law when it gets tested beyond disproof. He proved the atomic number using X-rays.
Me: How come Moseley never got the Nobel Prize like you did?
Henry: He was killed--took a Turkish bullet in the head at Gallipoli in 1915--the same year I was born.
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At the link, Isaac Asimov is quoted: "In view of what he [Moseley] might still have accomplished ... his death might well have been the most costly single death of the War to mankind generally."
Me: Moseley's Law?
Henry: Yes. A theory becomes a law when it gets tested beyond disproof. He proved the atomic number using X-rays.
Me: How come Moseley never got the Nobel Prize like you did?
Henry: He was killed--took a Turkish bullet in the head at Gallipoli in 1915--the same year I was born.
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Henry Moseley (1887-1915) |
Labels:
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Imagine If You Will, Another Dimension of Atoms...
Cobalt and nickel are elements 27 and 28, respectively, but this wasn't always so. Older textbooks often put cobalt and nickel together because they weren't sure which came first. Though there were chemical reasons to believe that cobalt preceded nickel in the Periodic Table, no matter how carefully they measured it, nickel always came out lighter than cobalt, even though it should be heavier.
Scores of new elements were discovered in the 19th century and back then weight measurements were used to identify them and to place them in the table. T. W. Richards won the Chemistry Nobel in 1914 "in recognition of his exact determinations of the atomic weights of a large number of the chemical elements." But realize that while the Periodic Table originally sorted and arranged chemical elements according to their atomic weights, the table actually sorts the elements according to their atomic numbers. The notion of atomic number was unknown to 19th century chemists.
A hypothetical sample of cobalt, nickel, and copper** ions would give a mass spectrum looking something like this:
Natural cobalt is monoisotopic (59Co), while nickel has five isotopes: 58Ni, 60Ni, 61Ni, 62Ni, and 64Ni, with the lightest being the most abundant. Note how 58Ni precedes 59Co. Why cobalt likes neutrons more than nickel does is an interesting question for which I have no answer.
Henry Moseley first showed that cobalt and nickel were correctly ordered despite their anomalous weights. Around the same time, J.J. Thompson invented mass spectrometry which sorts ions according to mass as shown above. Thompson discovered that neon had two isotopes but the concept of isotopes wasn't fully understood until James Chadwick discovered the neutron in 1932. Chadwick's discovery also enabled the subsequent syntheses of elements beyond uranium.
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*Tellurium (element 52) presents a similar weight anomaly because it is on average heavier than iodine (element 53).
**I wrote about copper isotopes back here and included it because it falls close to Ni and Co.
Scores of new elements were discovered in the 19th century and back then weight measurements were used to identify them and to place them in the table. T. W. Richards won the Chemistry Nobel in 1914 "in recognition of his exact determinations of the atomic weights of a large number of the chemical elements." But realize that while the Periodic Table originally sorted and arranged chemical elements according to their atomic weights, the table actually sorts the elements according to their atomic numbers. The notion of atomic number was unknown to 19th century chemists.
A hypothetical sample of cobalt, nickel, and copper** ions would give a mass spectrum looking something like this:
Natural cobalt is monoisotopic (59Co), while nickel has five isotopes: 58Ni, 60Ni, 61Ni, 62Ni, and 64Ni, with the lightest being the most abundant. Note how 58Ni precedes 59Co. Why cobalt likes neutrons more than nickel does is an interesting question for which I have no answer.
Henry Moseley first showed that cobalt and nickel were correctly ordered despite their anomalous weights. Around the same time, J.J. Thompson invented mass spectrometry which sorts ions according to mass as shown above. Thompson discovered that neon had two isotopes but the concept of isotopes wasn't fully understood until James Chadwick discovered the neutron in 1932. Chadwick's discovery also enabled the subsequent syntheses of elements beyond uranium.
_______________________
*Tellurium (element 52) presents a similar weight anomaly because it is on average heavier than iodine (element 53).
**I wrote about copper isotopes back here and included it because it falls close to Ni and Co.
Friday, January 13, 2012
It doesn't matter if you're a scientist or a bra-fitter, Lord Kelvin was right:
"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science, whatever the matter may be."
~Lord Kelvin
~Lord Kelvin
Selènè mooned the Xerox machine*
Selene, the moon goddess |
Chester Carlson put selenium's photoconductivity to practical use by inventing xerography and founding the Xerox corporation. Carlson patented xerography (which means dry writing in Greek) in 1942 and commercialized it. Selenium's role in xerography was to hold an electrostatic image long enough to attract toner ink for transfer to paper--and then to quickly forget what it saw. Selenium is no longer used in commercial copy machines, but the first ones did. A good historical read is here. Television, then a nascent technology, also used selenium early on. link
Though right next door to arsenic, selenium is not nearly as toxic--though its smell can be nauseating. Selenium disulfide puts the stink in dandruff shampoos, though I'm not sure if it's the selenium or the sulfur--both are chalcogens. Toxic in large doses, selenium is also an essential micro-nutrient, replacing sulfur in amino acids like cysteine and methionine and serving as an anti-oxidant.
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*Element 34, Selenium was named for Σεληνη [Selènè], Greek for Moon. Van der Krogt gives more history of the element's naming. Link
Labels:
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Thursday, January 12, 2012
Arsenic's Poisoned Reputation
Arsenic is called the "King of Poisons" and the "Poison of Kings" due to its long history. Interested readers (I'm looking at you, Jason) can GIY or perhaps even suggest a reference in the comments.
Lesser known is arsenic's more recent role in our own poison gas warfare program. I mentioned Lewisite here, but I thought that a more formal introduction was in order. Even a non chemist can recognize arsenic's central role in Lewisite's structure. Here it is:
Lewisite, chemical structure |
We made a lot of Lewisite shortly after WW I but we never deployed it as far as I know. Ridding our stockpiles has taken forever and an old cache was recently found in Washington, D.C. Arsenic just can't doff its nasty reputation, even cloaked in disguise.
Let's take a closer look at those copper atoms
How small can we see? Pretty small, it turns out. We can see atoms (see above)--not with light but with electrons (light is too crude of a yardstick and can't "measure-down" to the job). In Scanning Electron Tunneling Microscopy (STM), a tiny metal wand just an atom or two thick approaches a surface. Electrons, dripping from the tip of the sweeping probe, jump to a surface below, feeding signal back and mapping the atomic topography:
original |
Successive traces of electronic signals become a "photo" of the surface. The way STM works reminds me of the spark of life implied so long ago here. The technique is more fully explained here.
Suppose we could zoom a microscope down onto a pure copper surface to find out what's really there. I mean really there there. We'd find, even for ultra pure copper--heterogeneity. What looks the same is really different. No matter where we look, about one in three copper atoms has two "extra" neutrons because native copper comes in two isotopic flavors: 63Cu and 65Cu.
A while back, Michael Haz mentioned that pure copper native to Upper Michigan was distinguishable from pure copper native to South America. It's true. Copper sources have isotopic signatures. The natural ratio of the two copper isotopes varies slightly from place to place for various reasons. The reason(s) why they vary are complex and altogether unimportant here. The point is that they differ and they do so in a way that can be reliably measured--like fingerprints. A similar isotopic method has been used to trace the influx of South American silver into European coinage: link
Wednesday, January 11, 2012
Is Happiness Overrated?
Happiness is not on my list of priorities. I just deal with day-to-day things. If I’m happy, I’m happy–and if I’m not, I don’t know the difference.
~Bob Dylan (link)Happiness is so important that we're entitled to its pursuit. And yet, the word itself must be carefully parsed lest one feel entitled to equate it with mere gratification or the right to be left alone. Of course one can make that equivalence, but I don't think that's what Jefferson had in mind. What he did have in mind might be found here: Link.
Words change with time. The original concept of happiness is closely linked to luck or good fortune:
Happy
late 14c., 'lucky, favored by fortune, prosperous;' of events, 'turning out well,' from hap (n.) 'chance, fortune' + -y (2). Sense of 'very glad' first recorded late 14c. Ousted O.E. eadig (from ead 'wealth, riches') and gesælig, which has become silly. Meaning 'greatly pleased and content' is from 1520s. O.E. bliðe 'happy' survives as blithe. From Greek to Irish, a great majority of the European words for 'happy' at first meant 'lucky.' An exception is Welsh, where the word used first meant 'wise.'
Blake quotes Will Durant: "Societies enter stoic and exit epicurean."
Added: Sole reader of this blog post, Calypso Facto quips:
'Societies enter stoic and exit epicurean'- Hopefully that was the banner hanging over the secret, star-studded White House Halloween party.
Tuesday, January 10, 2012
More Jeff Beck (for LL)
A favorite scene of Jeff Beck with the Yardbirds from Michelangelo Antonioni's 1966 film Blow-Up. Jimmy Page too! Bonus cameo by Monty Python's Michael Palin at the 39 sec mark (he's to the right of the guy w/ glasses in the audience). I read that the woman in the stripped pants and silver jacket became some famous MP.
I can't seem to embed the video. This video tends to go up and come down quickly, so enjoy while you can: Link
I can't seem to embed the video. This video tends to go up and come down quickly, so enjoy while you can: Link
Sunday, January 8, 2012
You Are My Medicine, Part II
Ron tweeted me this link yesterday which I didn't see until this morning. Ed Sullivan hosted Dick Dale in 1963:
I'm no expert on these things but wasn't Dick Dale kind of "hunky"?
I saw Dale play up in San Juan Capistranolast year in 2010 and I wrote about it here. It was a very emotional show and at the time it looked like it might be one of his last. But thankfully, rumors of his demise were greatly exaggerated.
I'm no expert on these things but wasn't Dick Dale kind of "hunky"?
I saw Dale play up in San Juan Capistrano
Thursday, January 5, 2012
On Queue
Netflix this weekend:
A Woman in Berlin (2008) because commenter Allie recommended it;
Added: [This was a great movie and story. It's particularly poignant because the woman who drafted the original story faced attacks while still alive and stipulated that her identity never be revealed. She was "outed" 2 years after her death. link Her original diaries are still not open. The latter aspect reminds me of the missing originals to the Last Letters From Stalingrad saga. link.]
12 O'Clock High (1949) because I've never seen it; and
Chinatown (1974) because my wife admitted that she never cared about the water rights angle of the story and wants to see it again too.
Added: [I've seen Chinatown several times and it just gets better with age. My wife is reading Colossus (and urging me to read it too). That her got curious about California water rights and so the fictionalized story in Chinatown came up. We're already planning a road trip with the kids to the dam and to Vegas.]
A Woman in Berlin (2008) because commenter Allie recommended it;
Added: [This was a great movie and story. It's particularly poignant because the woman who drafted the original story faced attacks while still alive and stipulated that her identity never be revealed. She was "outed" 2 years after her death. link Her original diaries are still not open. The latter aspect reminds me of the missing originals to the Last Letters From Stalingrad saga. link.]
12 O'Clock High (1949) because I've never seen it; and
Chinatown (1974) because my wife admitted that she never cared about the water rights angle of the story and wants to see it again too.
Added: [I've seen Chinatown several times and it just gets better with age. My wife is reading Colossus (and urging me to read it too). That her got curious about California water rights and so the fictionalized story in Chinatown came up. We're already planning a road trip with the kids to the dam and to Vegas.]
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