A Random 10 for Bill Carroll's National Chemistry Week Extreme Tour
Chemistry (Chemistry)
Modern Chemistry (Motion City Soundtrack)
Chemistry (The Dygmies)
Delicious Chemistry (Juliet Kelly)
Chemistry (Semisonic)
Strong Chemistry (David Wilcox)
Chemistry of Spiders (Corcovado)
Relative Chemistry (Doctor L)
Bad Chemistry (Donna Regina)
Chemistry Lessons (Frenchmen)
random 10 : chemistry
Field of Science
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Change of address1 year ago in Variety of Life
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Change of address1 year ago in Catalogue of Organisms
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Earth Day: Pogo and our responsibility1 year ago in Doc Madhattan
Extreme Chemistry
Tomorrow Bill Carroll, the president of the American Chemical Society, heads out on the National Chemistry Week Extreme Tour. Bill is out to show how much fun chemistry can be, by highlighting this year's NCW theme: The Chemistry of Toys. He's also raising money for Project SEED which supports summer lab research experiences and college scholarships for economically disadvantaged students. Project SEED is in its 37th year and more than 8000 students have been supported.
Check out Bill's progress at the Extreme Tour Blog or catch the Tour's tunes. You can also sponsor one of Bill's many miles by donating to Project SEED.
science : chemistry : American Chemical Society
Check out Bill's progress at the Extreme Tour Blog or catch the Tour's tunes. You can also sponsor one of Bill's many miles by donating to Project SEED.
science : chemistry : American Chemical Society
Smooth Operators
The formulation of quantum mechanics in terms of operators lends it dash of elegance compared to the stodgy differential equations of Newtonian physics. In 1932 John von Neumann brought operator algebra to bear on quantum mechanics. von Neumann was unusually social, for a mathematician, and his home in Princeton the venue for many parties. He was also gifted across a wide range of field in mathematics, doing fundamental work in both my field and that of my husband (and our work is not connected in any way!).
What's an operator? The basic definition is a rule that changes one function into another. A more sophisticated one is a mapping between two function spaces. A function space is a collection of functions, each point in the same corresponds to a function. The functions are collected according to a set of rules, different function spaces have different rules associated with them. For example, the set of all functions that are real-valued on the interval 0 to 1 and have continuos 2nd derivatives would constitute a function space. A famous function space for quantum mechanics is Hilbert space.
You can, of course, construct classical physics in terms of operators as well; and quantum mechanics in terms of differential equations! The pedagogical approach to quantum mechanics generally brings operators explicitly to the table very early one, while the introduction of classical physics is often done without recourse even to the calculus.
Tags: Science, Chemistry, Quantum,Physics
What's an operator? The basic definition is a rule that changes one function into another. A more sophisticated one is a mapping between two function spaces. A function space is a collection of functions, each point in the same corresponds to a function. The functions are collected according to a set of rules, different function spaces have different rules associated with them. For example, the set of all functions that are real-valued on the interval 0 to 1 and have continuos 2nd derivatives would constitute a function space. A famous function space for quantum mechanics is Hilbert space.
You can, of course, construct classical physics in terms of operators as well; and quantum mechanics in terms of differential equations! The pedagogical approach to quantum mechanics generally brings operators explicitly to the table very early one, while the introduction of classical physics is often done without recourse even to the calculus.
Tags: Science, Chemistry, Quantum,Physics
It's a joke, right?
Some physical chemistry jokes collected by one of my p-chem students:
How many physical chemists does it take to wash a beaker?
None. That's what organic chemists are for!
A physical chemist is a student who goes to university thinking he might
want to be a physicist, but gets intimidated by the math.
Physical Chemistry is research on everything for which the negative
logaritm is linear with 1/T -- D.L. Bunker
Thanks to Alessandra!
On a historical note, D.L. Bunker is Don Bunker, a professor of physical chemistry at my alma mater, University of California, Irvine. He died suddenly during my freshman year.
How many physical chemists does it take to wash a beaker?
None. That's what organic chemists are for!
A physical chemist is a student who goes to university thinking he might
want to be a physicist, but gets intimidated by the math.
Physical Chemistry is research on everything for which the negative
logaritm is linear with 1/T -- D.L. Bunker
Thanks to Alessandra!
On a historical note, D.L. Bunker is Don Bunker, a professor of physical chemistry at my alma mater, University of California, Irvine. He died suddenly during my freshman year.
Cracking the Top 100 Podcasts
I found out today, quite by accident, that the podcast of my quantum mechanics lectures has been hovering in Apple iTunes Top 100 list! My students are not subscribing through iTunes (they are using other feed aggregators) - so is quantum chemistry suddenly fashionable?
Let's hope!
Let's hope!
When is red yellow?
I promised my class that by the end of the semester they'd know why flamingos are pink and Cheetos are orange. In that vein, last week's quiz included a question asking them to figure out which of two labels belonged on a bottle of reddish violet solution and which went on the yellowish solution.One student correctly labled the bottles, but wondered if my choice of compounds was a red herring. She noted that the name of the compound that she predicted would produce the reddish solution (canthaxanthin) meant "yellow" in Greek. I told her that, in fact, I hadn't known that xanthin meant yellow and wasn't trying to mislead them!
This sent me on a hunt to discover why a reddish compound was named for "yellow". Turns out canthaxanthin is named for the mushroom species from which it was first extracted (Cantharellus cinnabarinus) and the Greek for yellow (xanthin). Cantharus is Latin for a two horned drinking cup, which the fungus resembles. The color can tend toward the orange, so that may be the source of the "yellow" in the name.
Weird Words of Science 7: nano dreams
Orac is dreaming of an iPod nano.
Where does nano come from? The root comes from the Greek for dwarf. The prefix was formally adopted in the late 1940s to mean 10-9, as in a nanometer. The construction had been floating around since the early part of the 20th century. The OED catalogs the first appearance in English in nanphanerophyte (a small shrub), but the French were using it about 50 years earlier.
Nano along now carries the connotation of the very small, typically on the nanometer scale. A bond between two carbon atoms is about 1/10 of a nanometer.
Where does nano come from? The root comes from the Greek for dwarf. The prefix was formally adopted in the late 1940s to mean 10-9, as in a nanometer. The construction had been floating around since the early part of the 20th century. The OED catalogs the first appearance in English in nanphanerophyte (a small shrub), but the French were using it about 50 years earlier.
Nano along now carries the connotation of the very small, typically on the nanometer scale. A bond between two carbon atoms is about 1/10 of a nanometer.
Quantum jokes?
Q: Why won't Heisenberg's operators live in the suburbs?
A: They don't commute.
To really understand the joke, it's helpful to know the general form of the Heisenberg uncertainty principle. The Robertson-Schroedinger inequality
leads directly to the more general statement of the Heisenberg uncertainty principle. The piece in the little square brackets [A,B] on the right hand side is called the commutator of the operators A and B. When A and B don't commute, [A,B] is non-zero and you end up with uncertain simultaneous measurements.
Commuting operators can be applied in any order and you get the same result.
My 9 year-old says that if you have to explain a joke, it's not a joke. And by this definition, he says, this post is not a joke!
A: They don't commute.
To really understand the joke, it's helpful to know the general form of the Heisenberg uncertainty principle. The Robertson-Schroedinger inequality
leads directly to the more general statement of the Heisenberg uncertainty principle. The piece in the little square brackets [A,B] on the right hand side is called the commutator of the operators A and B. When A and B don't commute, [A,B] is non-zero and you end up with uncertain simultaneous measurements.
Commuting operators can be applied in any order and you get the same result.
My 9 year-old says that if you have to explain a joke, it's not a joke. And by this definition, he says, this post is not a joke!
Flying Objects
One of the major uses of helium is to keep superconducting magnets very cold. The coils must be kept at a chilly 450 degrees Fahrenheit below zero in order to achieve the strong magnet fields necessary for magnetic resonance imaging. MRI is a widely used medical imaging technique, partly because the radiation used is of much lower energy than that need for CT scans, for example. MRI is actually an application of a quantum mechanical phenomena called NMR (nuclear magnetic resonance). The energy states of the nuclei in a magnetic field can be changed by tickling them with very small amounts of energy (radio waves to be precise), and the changes in these states can be used to produce an image of living tissue. The stronger the magnet field, the more easily detected the energy changes are, hence the use of the strong field superconducting magnets.
So how strong are these magnets? They are on the order of 1 Tesla, thousands of times more powerful than your basic horseshoe magnet. If you're not careful with a superconducting magnet of this strength, it can suck up a lot of metal. See the photos here for some stunning examples.
So how strong are these magnets? They are on the order of 1 Tesla, thousands of times more powerful than your basic horseshoe magnet. If you're not careful with a superconducting magnet of this strength, it can suck up a lot of metal. See the photos here for some stunning examples.
Strategic Reserves
President Bush recently announced that the strategic petroleum reserves would be breached to counter gasoline shortages in the wake of Hurricane Katrina. Did you know that government maintains strategic reserves of other materials as well? The strategic helium reserves are kept in Amarillo, TX in a natural formation called the Bush Dome. The He reserve was created in 1925, when the major strategic use was military dirigibles. Helium extraction is incidental to methane (natural gas) production. These days helium is used in magnetic resonance imaging to cool the coils in the magnets so they will superconduct and other cryogenic applications. The reserve contains about 30 billion scm (an scm is a cubic meter at standard conditions -- not a square cubic meter as one report states!)
Camille Minichino visited the chemistry department at Bryn Mawr this week. She is the author of the Periodic Table mystery series. In her second book, The Helium Murder, physicist Gloria Lamerino suspects Congresswoman Hurley has been murdered because of her position on the sale of helium in the reserves.
Standard conditions for a gas are 298 K and 1 atmosphere of pressure.
Camille Minichino visited the chemistry department at Bryn Mawr this week. She is the author of the Periodic Table mystery series. In her second book, The Helium Murder, physicist Gloria Lamerino suspects Congresswoman Hurley has been murdered because of her position on the sale of helium in the reserves.
Standard conditions for a gas are 298 K and 1 atmosphere of pressure.
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