| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| eustatic | "woah! " | Read more » | about 11 years ago | |||
| eustatic | "cool " | Read more » | about 11 years ago | |||
| jeffh | "There are tradeoffs, but it's certainly worth trying violet/UV LEDs. The wavelengths are roughly equivalent, but the LED emits across a broader ran..." | Read more » | about 11 years ago | |||
| warren | "@jeffh - do you think it'd be possible to do such analysis using a blue or ultraviolet LED, instead of a laser? I wonder if it would be safer (for ..." | Read more » | about 11 years ago | |||
| jeffh | "Very nice experiment, and a great set-up for measurements. I bought a 405-nm laser a couple of months ago, and that's a much better wavelength for ..." | Read more » | about 11 years ago | |||
| warren | "@stoft - the reference was just the UV laser. I didn't have an empty vial at the time but you're right that we should do that test. The sample is a..." | Read more » | about 11 years ago | |||
| greggbone | "I would love to be able to characterize oils, olive oil in particular. Two areas of characterization: Adulteration and Quality. A very high perce..." | Read more » | about 11 years ago | |||
| stoft | "Jeff, nice experiment. Yes, UV is the right choice -- the shorter the wavelength the better. I'm assuming that the UV-light 'reference' was with wa..." | Read more » | about 11 years ago | |||
| warren | "This looks great! Now, the tough part -- detecting enough light to get a spectrum. If you let the sample settle for a few days, does it look more c..." | Read more » | over 11 years ago | |||
| warren | "Also, i ended up ordering those crude oil samples online: http://publiclab.org/notes/warren/05-03-2013/crude-oil-samples-for-purchase-online I'm h..." | Read more » | over 11 years ago | |||
| warren | "Hi Scott -- what kind of light are you using? When i've done this, i've let it settle in a clear container so I can see that all the muck has real..." | Read more » | over 11 years ago |