Everyday Scientist

deep-tissue imaging spam?

I assumed that this was spam regarding two-photon or other deep-tissue imaging:

Nope. It’s non-science spam.

fluorescent cognac

I was watching bad TV the other day, and I got bored and started playing with a cool LED pen Thorlabs gave me. I was also drinking some VS (the cheap stuff) Courvoisier cognac. I was surprised to see fluorescence coming from the cognac when illuminated with the blue LED (the fluorescence is the greenish glow):

I suppose that it shouldn’t be surprising, given that cognac is so aromatic! But a visible absorption and green fluorescence isn’t from benzene or something—it’s from a real fluorophore. Cool.

So I wonder what fluorophore is in cognac. I know that coumarin (general structure above) is found in some plants, such as cinnamon, and some coumarins absorb in the blue. And there are a lot of tannins in wooden barrels.

I found these fluorescence spectra of brandy (B), whisky (W), slivovice (S), and juniper spirit (J). Note that the brandy—cognac is a brandy—does fluoresce in the blue/green.

DIY oobleck on a speaker

Remember those Oobleck fingers in PRL? I finally got around to trying it at home.

And a video (more below):

My cousin and I bought a crappy old speaker to $3, tore off the cover, and spread a thin polyethylene bag (like the bags you put vegetables in at the grocery store). We used a free waveform generating software to apply sinusoidal waves at a range of frequencies—anywhere from 10-200 Hz had an effect. The oobleck was just a mixture of corn starch and water.

I was totally surprized that we actually saw those strange finger things! They weren’t as cool as in the PRL paper, but ours was a fairly ghetto setup. I couldn’t get those persistent holes to form, but whatev.

Here are the rest of the videos.

math limit humor

I dunno why, but these really cracked me up:

Hehe.

voted; and an alaska carbon?

I voted this morning. The polls opened at 7, but I slept in. By the time I got to my polling place, there was no line at all. The poor folks that got there at 7 (or before) waited in an hour-long line.

Also, check out that Alaska (?) carbon.* Man, JACS is really screwing up lately.

__________________________

* Heck, this is a Jovian carbon!

are we still here?

It’s important that we all keep up with the dangerous things that are happening in the world. Fortunately, there are people out there willing to slog through the data and pass on the results to the rest of the world. Of course, there is also this, but it has an obvious liberal bias.

(Thanks, Nanoscale Views.)

chem art

I took a metal-casting class last spring. I made a few pieces from Epi tubes, because they were fun to manipulate and melted away in the mold. Here are my contributions to the world of Chemistry Art:

And a pipet tip stabbing a tube:

And a keychain:

I don’t actually hate Epi tubes.

attila szabo’s autobiography

If you want a fun and inspiring story, read Attila Szabo‘s autobiography for his JPCB Festschrift (here). It’s only 4 pages.

Here’s a great except:

How could I get my hands on a little red phosphorus? Who would sell some to a 14 year old boy? Well, Fisher Scientific would.

Enjoy!

olympic FRET

In the spirit of the Olympics, I have a new idea: In order to directly probe the dynamics of the Olympics using fluorescence, we need to label athletes and measure their locations and conformations.

For instance, labeling Michael Phelps with Cy3 and Cy5 will allow us to locate his position in the pool with nanometer precision.

Moreover, we should also be able to watch the FRET trace to observe the conformational changes of his arms. In this fashion, we should be able to determine if Phelps travels down the lane using the widely promoted “butterfly” model, or the more controversial “flagellar” model, which posits that his arms spin like propellers.

This work will be continued and I wish to reserve the field for myself.

the edible laser

The beginnings of the laser age must have been a fun time: crazy new experimental possibilities, beautiful optical demonstrations, dye lasers squirting carcinogens everywhere, and new lasing materials around every corner.

The “edible” laser is a great example:

High-gain directional stimulated emission has been observed for a number of dyes in gelatin with pumping by a nitrogen laser or a liquid dye laser. For some dyes the gel is made with water and gelatin; for others a detergent must be added or glycerin used instead of water. (Source: Hänsch, T.;  Pernier, M.;  Schawlow, A. IEEE Journal of Quantum Electronics 1971, 7, 45-46.)

I probably would not eat that for multiple reasons: I’m vegetarian, the detergents probably wouldn’t taste good, a nitrogen laser in the eye is unappetizing, and I doubt that fluorescein is food-grade. Theodore Hänsch describes some of these fun laser stories in Optics and Photonics News 2005, 16(2), 14-16 (or the PDF here).

It’s a fun read. Or just read the first page, then look at the pictures, like I did.

happy pi day!

Glad we caught this one (unlike last Pi-Approximation Day).

That’s all.

Do Not be Shame Because of Your Instrument Size

From an email I received this morning:

Your chick shack up with your mate that is why you are alone.

By reason of of his instrument size. Chicks love huge device.

Do not worry bro. Today you have good possibility to Increase your machine size.

Lots of men the world over have increase. Now its your turn.

What the hell? My delay line is already 5 ft, quadruple passed. That’s a full 40 ns of pump-probe action. What I lack in girth (of pulse bandwidth), I make up for in S/N. Too bad it wasn’t enough to save my marriage.

Hotel Mauna Kea

Sent to me by my research advisor:

single-molecule feng shui

We just moved to a different apartment, and started doing some decorating. Man, we went all out. You know, lovin’ it.

And I just don’t get enough of looking at single fluorescent molecules while I’m at lab. I miss them when I’m home. So we decorated our living room so that I never have to feel too far away from my fluorophores:

Figure 1. (left) sample under white light, (middle) white light and single-molecule emission overlaid, and (right) single-molecule emission only. We have some problem with background, but we are able get achieve signal-to-background ratios sufficient for imaging.

I really have no idea why my girlfriend let us do this. It was partially her idea, really. Maybe she wanted to keep me home longer, staring at the walls, writing down filenames, instead of heading into lab.

bad chemicals

OK, I know this is old news (Paul already blogged about it), but I just received my very own hard copy in my mailbox, so I have to post it:

I just love this! I want to use it next time I teach gen chem. I know chemistry can be hard. Look, even OUP and ACS get it wrong sometimes. And I mean really wrong.

What I don’t understand is how did they do this?!? Which chemical-drawing program let’s you make a hydrogen join the ring of benzene? Or have oxygen form four bonds? Or… They must have had little red squares all over their screen!