Saturday, December 29, 2007

Apples and Oranges

From a dubiously respected source, we find proof of the validity of the Visual Gestalt ("eyeballing") method of matching chromatograms.


Figure 1: Infrared transmissibility curves

By the Brenna criteria of general arrangement and relative heights of peaks, there appears to be complete isomorphism between the targets, showing that one can indeed compare apples with oranges.

5 comments:

Larry said...

Thanks a lot, TBV. I must now re-examine my entire life and everything I'd thought I'd believed.

GMR said...

Larry, TBV,

While the quantification of the "Granny Smith Apple and the Sunkist Orange" is visually similar, I find the identification portion of the comparing apples and oranges lacking in this example. Sunkist is a cooperative of orange growers and is not a variety of orange. Varieties of oranges include: Navel, Valencia and Blood oranges. This analogy may be very apropos to the missing Mass Spec data.

It is fun read.

--GMR

Russ said...

Wow, pictures can be so misleading!

Hear (from another source) is an analysis for the mineral content of an apple and an orange compared.

www.nutritiondata.com/facts-C00001-01c20TB.html

Apple, raw, with skin (Includes USDA commodity food A343)
1 cup, quartered or chopped (125g)

Minerals:
Calcium 7.5 mg
Iron 0.1 mg 1%
Magnesium 6.3 mg
Phosphorus 13.8 mg
Potassium 134 mg
Sodium 1.3 mg 0%
Zinc 0.0 mg 0%
Copper 0.0 mg 2%
Manganese 0.0 mg
Selenium 0.0 mcg
Fluoride 4.1 mcg

www.nutritiondata.com/facts-C00001-01c20Vm.html
Orange, raw with peel
1 cup (170g)

Minerals: scaled to 125g(x.735):
Calcium 119 mg 87.47
Iron 1.4 mg 1.03
Magnesium 23.8 mg 17.49
Phosphorus 37.4 mg 38.14
Potassium 333 mg 244.76
Sodium 3.4 mg 2.50
Zinc 0.2 mg .15
Copper 0.1 mg .07
Manganese ~
Selenium 1.2 mcg .88
Fluoride ~

Ali said...

Thank God, I was about to launch into a huge Ali exclusive, until I actually read your link.

I can relax into my welcome ignorance comfort zone -- apart from ACDC screaming to me that they're back in black through the head-phones -- a life saver.

Thank god for ACDC. Thank god for rock ...

Lowryder said...

Incidentally, FTIR is Fourier Transform Infrared Spectroscopy.

And all TBV readers should know the difference between spectroscopy and chromatography by now. :)