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Final Data Analysis for My New 0.11mm Entrance Slit Design

by dhaffnersr |

Abstract

This is the final data analysis for my new 0.11mm slit design. I used Eosin Y as my medium for sample analysis since its spectral data is well documented, I have used the Oregon Medical Laser Center again as my reference for Eosin Y in ethanol. The absorption values were collected using a spectral bandwidth of 1.6nm using the DH 4.0 v4 spectrometer, an excitation emission matrix was used to illustrate in detail, the emission peak of the sample (Eosin Y,) in order to clarify in a logarithmic view, the resolution factor of the new entrance slit design.

Figure 1 shows the spectrum of Eosin Y in ethanol from the OMLC (Oregon Medical Laser Center) and my sample (Eosin y in ethanol,) the raw data from my sample scan is included also in that figure. The absorption data is the most interesting, because I am within 0.41nm of the maximum absorption of 524.8nm measured by the OMLC. This means mathematically, I have an error factor of only 0.07 percent.

Figures 3 and 4, are the excitation source I used for fluorescing the Eosin Y sample, a 532nm DPSS 150mW green portable laser. This is what I used as my Blank (ethanol,) to zero out my spectrometer. Although it does NOT depict the spectrometer’s resolution factor, it does show the sharpness and stability of the laser line itself at a FWHM of 0.57387 @ 532nm.

The title picture is the plot illustrating all 5 sample spectra of Eosin Y, I chose sample number 1 because at a concentration level of 39mg, it closely matched that of the OMLC’s spectrum(543nm) both in FWHM and emission peak @ 544nm.

I am convinced, that this final analysis has shown that the 0.11mm Gillette razor blade open-air design entrance slit, has performed in a superior manner to that of the acetate film slits that Plab sells.

Sample preparation and Methodology

EOSIN_Y_pic_smaller.png Eosin Y 1% aqueous solution

Using the Gem50 Smart scale, I first weighed 1 drop of eosin y to determine volume weight of each drop, which equaled 0.039g. 5 sample test tubes (13X100mm glass test tubes with screw tops) were prepared and cleaned with acetone and rinsed with distilled water, to ensure no contamination of the samples. Each test tube was labeled 1 thru 5, starting with test tube #1 with 1 drop of eosin y and so forth until all 5 sample test tubes had the appropriate amount of eosin y. Test tube#1 – 1 drop 39mg g/1000 = mg Test tube#2 – 2 drops 78mg Test tube#3 – 3 drops 117mg Test tube#4 – 4 drops 156mg Test tube#5 – 5 drops 195mg

Each test tube was filled with 10ml of ethanol (lab grade – 95% purity {200 proof}) using disposable plastic pipettes. Next, I prepared 5 UV plastic disposable cuvettes, having a wavelength range of 240 – 2200nm, by setting them in order on a cuvette holder numbered 1 thru 5. I transferred 2.5ml of the dilute sample solutions from each test tube to their respective cuvettes and capped.

_To ensure quality control in transferring the dilute solutions to the appropriate cuvettes, each transfer was done using an individual disposable pipette. _

Emission spectra was collected using perpendicular geometry (90degree angle.) using a DPSS 150mW 532nm green laser source.

Absorption spectra was collected using forward facing geometry, with a Solux 4700K 12vdc tungsten lamp as the radiant light source.

This is the 2D EEM plot (excitation emission matrix) for the Eosin Y sample: EEM_plot_1.png

Next is the Zoomed in view of the same EEM plot, showing the maximum peak @ 544nm for Eosin Y in ethanol, the plot clearly illustrates a highly uniform and un-distorted peak for the 0.11mm metal slit. EEM_plot_2.png

Next is the data for the collected absorption spectra of Eosin Y, with the first table showing the data for my reference on the bottom left corner for the OMLC and the main data for my Eosin Y sample.

Absorption_data.png

Absorption_data_2.png

Next if figure 1, which has the OMLC (Oregon Medical Laser Center) Spectra for Eosin Y in ethanol, plus my collected spectra of Eosin Y in ethanol and it's accompanying raw data.

comparison_omlc_mine_FIG_1.png

Figure 2 is my emission plot for Eosin Y in ethanol showing a maximum peak @ 544nm.

comparison__mine_FIG_2.png

The next graphic are the specifications for the 532nm laser that I use:

SPECS_for_Laser.png

This next plot, is the Blank (ethanol) that I used to "zero" out my spectrometer, and the subsequent plot of the zoomed in view of the laser peak.

LASER_LINE_FIG_3.png

LASER_LINE_FIG_4.png

References

http://omlc.org/spectra/PhotochemCAD/html/061.html

http://cnqzu.com/library/Anarchy%20Folder/Chemistry/MISC/Sample%20Preparation%20Techniques%20in%20Analytical%20Chemistry%20(Wiley,%202003).pdf

http://publiclab.org/notes/dhaffnersr/08-12-2016/snr-data-for-eosin-y-study-on-8-10-2016

http://publiclab.org/notes/dhaffnersr/08-20-2016/eem-2d-spectrums-showing-evidence-of-attenuation-from-imperfections-in-acetate-film-strips

http://publiclab.org/notes/dhaffnersr/08-20-2016/comparison-values-for-0-09mm-and-0-11mm-slit-width



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