DC Baltimore


Baltimore-Washington Section of the Society for Applied Spectroscopy

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April and May Historical Events In Spectroscopy by Leopold May, Catholic University

June Historical Events in Spectroscopy by Leopold May, Catholic University


Okay, so we missed the boat for a Tour Speaker again this year. I tried. Oh! How I tried! But, alas, we weren't on the tour route once again. However, all is not lost! We have students and we have sponsors. Ergo, we have a meeting! Tuesday, May 4th at our favorite (translation: easy to find and reliable) Maryland restaurant, the West End Grill in Bethesda, we are having a Student/Sponsor night (pretty catchy title, hunh?) At this meeting, Mr. Christopher Kidwell from the University of Maryland, College Park and Mr. Michael Minnich from the George Washington University will each receive the 1999 Baltimore-Washington SAS Graduate Student Award. Both Chris and Mike will present the graduate research that won them this coveted distinction.

As if that wasn't enough to mark your calendars, we will also have brief presentations from our local section corporate sponsors! Who are they? Look ahead in this bulletin. Wow! Won't this be neat? This is YOUR chance to talk with the pros about their products and services. Up close and personal. They are there for you. It is an opportunity that only comes along once each year, so don't miss it!

Okay, on to further business. Where are all of my eager volunteers for the vacant officer slots? John Canham, of NASA Goddard fame, has agreed to run for President-Elect. He is currently unopposed, however. Surely someone out there wants to help John make next year the best it can be. Since the TWO delegate slots are also open, whichever candidate is not chosen for President-Elect could still serve the SAS as the local section delegate at FACSS and PittCon. And, if high finance is your specialty, we need a Treasurer, too. Jeb Taylor has done a fine job in this capacity for about three terms now. He deserves a break! So, you see, no one is a loser. This isn't about self-esteem. It's about making a difference. To paraphrase: "Ask not what your local section has done for you. Ask what you can do for your local section." (I'll even give you a hint...run for an office!) Okay, I'm through begging. Next, I start volunteering people. I'm compiling a list. Be afraid! Be very, very afraid. In other sad news, the National office has sent me a "friendly" notice that some people are tardy in paying their dues. Please pay your dues.

The National office also sent me a news brief that one of the founding members of our section, Albert A. DiLeonardi, passed away recently. As I have only been in the area for the past eight years, I am not familiar with Mr. DiLeonardi's contributions to the SAS. However, for those of you who knew him and to his family, you have my deepest sympathy. Lastly, several current members have recently suffered from severe illnesses. They are in our thoughts and prayers for a speedy recovery.

Well, this is likely to be my last newsletter as President of the section. My sincere thanks to Mike Epstein for keeping our web page current throughout the year. I was often told that this site supplied the newsletter much more readily than "snail mail" efforts. We have talked about using e-mail and/or the web site as alternatives to the standard hard copy. If this suggestion meets with enough approval, it may become the norm beginning with the fall editions. As always, your opinions are welcome. This year was quite successful, thanks to the help of my fellow officers: Kris Patterson, David Hill, and Jeb Taylor. It was always a team effort for which I am very grateful. I look forward to a nice turn out for our students and sponsors on Tuesday, May 4. Have a safe and healthy summer.

Respectfully submitted,
Diana Ciurczak

Meeting Announcement


Christopher Kidwell and John Ondov


Michael G. Minnich and Akbar Montaser

Date: Tuesday, May 4, 1999

Place: West End Grill, 7904 Woodmont Ave., Bethesda, MD, 301-951-9696

Time: 6 pm Social Hour, 6:45 pm Dinner, 8 pm Seminar.

Cost: $20 -Choice from the menu. Included with each meal is House Salad, Coffee, Tea, or Soft Drink and Dessert.

Reservations: Please make your reservations by NOON, Friday, April 30, 1999 by calling Diana Ciurczak at work 202-324-1149, or e-mail at dianac@erols.com

Directions: From the Beltway take Wisconsin Ave. south past NIH. Take a right turn on Woodmont Ave. Restaurant is after the 4th light. Use street parking or the parking garage on the right in the next block.



Christopher Kidwell and John Ondov
University of Maryland, Department of Chemistry

A prototype aerosol concentrator has been developed and interfaced to a simultaneous multi-element graphite furnace atomic absorption spectrometer to permit semi-continuous determination of the concentrations of up to 12 elements in ambient aerosol samples. In the prototype concentrator, particles were grown at a flow rate of 100 L/min by condensation of water vapor. Saturation was achieved with an annular steam injector, followed by condensation in a vertical tube, with the grown droplets collected by impaction in a single-jet impactor. The collection efficiency of the system was determined using 0.1, 0.5, 1, and 3 um mono disperse fluorescent polystyrene latex particles. The system was further tested by sampling a test aerosol of NIST Standard Reference Material 1648, Urban Particulate Matter. Up to 12 elements were analyzed in three separate batches by simultaneous multi-element atomic absorption spectroscopy. Elements were grouped according to similar analytical conditions and expected concentrations. Details of the experimental setup and analysis of samples will be presented.


Michael G. Minnich and Akbar Montaser
The George Washington University, Department of Chemistry

Since its introduction, argon inductively coupled plasma mass spectrometry( Ar ICPMS) has proven to be capable of rapid elemental and isotopic analysis of over 70 elements. The determination of some elements, however, is complicated by spectral interferences which occur when the nominal mass of two species is the same. Spectral interferences are particularly troublesome for determinations at trace levels. Polyatomic spectral interferences arise from plasma species (Ar adducts) and solvent species (O adducts from aqueous solutions). Although mathematical corrections using the isotope ratios of the elements are available, it is difficult to correct for the contribution from polyatomics. For some elements, adjusting the operating conditions of the plasma and reducing the plasma potential is necessary to reduce interfering background ions. This results in the generation of a "cool" plasma condition in which the ionization of argon is suppressed. The cool plasma is attained by reducing the rf power, increasing the nebulizer gas flow rate, and increasing the sampling depth of the plasma. The normal plasma spectrum is dominated by O+, Ar+, ArH+, ArO+, and Ar2+. The cool plasma spectrum, however, is dominated by H3O+, NO+, and O2+. The cool plasma allows measurement of the most abundant isotopes of K (m/z = 39), Ca (m/z = 40), Fe (m/z = 56), and Se (m/z = 80) by attenuating 38ArH+, 40Ar+, 40Ar16O+, and 40Ar2+, respectively. All elements except K have usable less abundant isotopes, but sufficiently low detection limits cannot be obtained under normal plasma conditions. The semiconductor industry is particularly interested in this method for evaluating reagent purity.

In this work, the cool plasma conditions suitable for the direct introduction of microliter volume test samples are investigated. The differences between the normal plasma and cool plasma mass spectra will be discussed. Sensitivity, detection limits, and precision will be shown for a wide range of elements under normal plasma and cool plasma conditions. The cool plasma will be applied to the analysis of samples that cannot be measured by the current technology.

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Your Baltimore-Washington Section Officers for 1998-1999:

Chair: Diana Ciurczak

Chair-elect: Larry Pollack, SAIC, 703-333-5548. larryp@saic-cvr.com

Secretary: Dave Hill, USDA, 301-504-8282, hill@307.bhnrc.usda.gov

Treasurer: Jeb Taylor

Delegates: Scott Baker, USDA and Mike Epstein, Hood College

Newsletter Editor: Kris Patterson

Science Fair and Student Award Committee: Bob Koons

I.L. Barnes Award: John Moody

Web page editor: Mike Epstein

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Visit our local section sponsor WWW pages:

The Perkin-Elmer Corporation - Analytical Instruments Division



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Past Issues of the Baltimore-Washington Section Newsletter (including Historical Events in Chemistry)


Spectrum Go to the National SAS Home Page

For more information concerning Baltimore-Washington Section activities, email Diana Ciurczak dianac@erols.com

Page prepared by: Mike Epstein
Last Modified: April 9, 1999