Spectroscopic Analysis

EM_Spectrum3-new
Image by NASA [Public domain]

Spectroscopy is but one type of analysis I regularly perform. Below is a description of several of the techniques and the information each technique provides.

Spectroscopy involves the measurements of quantities as a function of frequencies or wavelengths, including how energy interacts with matter. These interactions provide information as to the identity and quantity of the composition of the matter.

Energy Dispersive X-ray Spectroscopy (EDS or EDX)

EDS is used to evaluate the elemental composition of materials within a scanning electron microscope (SEM), exciting the sample with X-rays, and then measuring the energy levels of X-rays emitted, which are specific to each element.

Fourier Transform Infrared (FTIR) Spectroscopy

FTIR spectroscopy is a technique in which infrared energy is used to excite fundamental vibrational and associated rotational-vibrational modes of molecules in the mid-infrared, approximately 4000 to 400 cm-1. These vibrational modes correspond to molecular structures. Attenuated Total Reflectance (ATR) is a technique used with FTIR, which allows liquid and solid samples to be studied directly without further preparation. In ATR-FTIR, an infrared beam is directed through an optically dense crystal at a certain angle and internally reflects through the crystal, producing evanescent waves. When the crystal is pressed against an infrared active material, the infrared radiation from the evanescent waves penetrates typically 1 to 4 micrometers into the sample.

Ultraviolet/Visible (UV/Vis) Spectroscopy

UV/Vis is used to measure electronic transitions of molecules in the ultraviolet to visible spectrum, approximately 180 to 800 nm. These transitions correspond to chemical structures which determine to amount of light energy absorbed, transmitted, and reflected, and can be used to characterize certain compounds and optical properties of materials.

X-ray Fluorescence (XRF) Spectrometry

X-Ray Fluorescence (XRF) is used to identify composition and plating thickness for elements ranging from titanium (Ti, element 22) to uranium (U, element 92). By bombarding a sample with high energy X-rays, secondary (or fluorescent) X-rays can be emitted which are characteristic of the atoms present in the sample.

Lehigh Nano for Business 2010 Conference

Lehigh-Nano-Health-Safety-2010 On May 26, 2010, I attended the Lehigh Nanotech Network’s Nano for Business 2010 Conference. I was invited to speak as a panelist on the “Health and Safety” panel.

In the picture to the left, I’m on the panel with Frank E. Ehrenfeld III, Laboratory Director, nanoTEM and IATL, ASTM D56.03 and Mike McGuiness, Principal, Haskill Toxicology Laboratories, E.I. du Pont de Nemours & Company. I’m in the middle.

More information about the conference can be found here.

Electronics Manufacturing Articles

1280px-Computer_Circuit_Board_MOD_45153621

Photo: Harland Quarrington/MOD [see page for license], via Wikimedia Commons, © Crown copyright 2012

One of my company newsletter articles in EMPFasis, a monthly Navy deliverable from the Electronics Manufacturing Productivity Facility or EMPF, was reprinted in the April 2010 issue of “Printed Circuit Design & Fab / Circuits Assembly”.

Other articles that I wrote have covered:

My First Peer-Review Publication

My first peer-reviewed publication has come out in the Journal of the Electrochemical Society, entitled: Electrochemical Deposition of a New n-Doping Polymer Based on Bis(thienyl)isopyrazole. It is based on some of the work I performed during my postdoc at China Lake. I repeated the synthesis and ran the electrochemistry under different conditions to get more information about the molecule.