Have LC lab, will travel. Testing propellant stability after Operation

Testing propellant stability after Operation Desert Storm. Gail Y. Stine. Anal. Chem. , 1992, 64 (7), pp 453A–455A. DOI: 10.1021/ac00031a002. Public...
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Have LC lab, Will Travel Testing Propellant Stability after Operation Desert Storm tne conclusion of WDeration Desert Storm, one of the problems facing the U.S. Navy was ensuring that unused propellant was safe to ship home after being in the Saudi Arabian desert. Modern gun propellants had never before been used under such severe desert conditions, and there was no way to predict how the propellant might have been affected. Furthermore, the war lasted 100 hours instead of the expected 100 days, and the majority of the gun ammunition sent to the Gulf was not used but instead was stored temporarily in ammunition dumps. Under normal conditions, the propellant would have been sent to the Naval Surface Warfare Center, Indian Head, MD, to determine the stabilizer content. However, Marine and Navy officials believed that operational readiness would be jeopardized if the propellant were shipped back to the United States before it was tested.

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This article not subject to U.S. copyright. Published 1992 American Chemical Society.

Gail Y. Stine Propellant Analysis Branch Indian Head Division, Naval Surface Warfare Center Indian Head, MD 20640

I had the opportunity last spring to spend 33 days in the desert analyzing gun propellant using a mobile LC laboratory. As manager of the Propellant Analysis Branch at the Naval Surface Warfare Center, I was given two months to design and implement

a mobile lab in the desert of Saudi Arabia. Together with Irma DalCanton, a physical science technician, we decided what resources would be needed for our journey to Saudi Arabia. Once there, we worked amid severe environmental conditions, including heat and blowing sand, and cultural restrictions against women that limited our freedom of movement. We set up the lab at an ammunition dump operated by the Marine

Corps near A1 Mishad, 60 miles south of the Kuwaiti border. Approximately 70% of the gun propellant that was not used during the war was u n loaded there for testing, inventory, and shipment home. We needed to determine whether the propellant could be loaded onto Marine expeditionary ships bound for other missions, shipped home for further tests and storage, or destroyed on site. All instrumentation, equipment, and consumable supplies had to be purchased and shipped to the site within two months. Planning efforts revolved around the fact that there would be no opportunity to procure spare parts or supplies in that part of the world. In addition, instrumentation and supplies had to be packaged to sustain harsh shipping conditions. The crates of equipment remained on the tarmac at Dhahran airport for 10 days before being transported by truck over unpaved roads 150 miles into the desert. The lab was set up in one half of a semitrailer equipped with electricity and an air conditioner. The Marines furnished a portable generator to provide electrical power. A fuel truck came by once a day (if we were lucky)

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h m Caveman to Chemist Circumstances and Achievements hat was the connection between early chemistry and magic? What was the logic that made alchemists think they could make gold out of lead? Why were gases not recognized until the 17th century? Why did it take 49 years before Avogadro’s hypothesis was accepted? In From Caveman to Chemist. author Hugh Salzberg traces the oddities of chemistry, examining cultural and political influences on the ideas of chemists. He follows the evolution of chemistry from the Stone Age beginnings of ceramics and metallurgy, through the rise and decline of alchemy, to the culmination of classical chemistry in the late 19th century. Chapters 1 through 9 lead from prehistoric technology, through ancient and medieval science to the study of chemicals and reactions that resulted in the 16th century birth of scientific chemistry. Subsequent chapters focus on key chemists such as Sala, Boyle, Black. lavoisier. Dalton, Berzelius. laurent. and Arrhenius as they developed the ideas that led to classical chemistry and the concepts of molecules, chemical reactions, homology, valence, and molecular formulas and structures, among others. Twenty topical illustrations enhance the text. Six timelines and two maps help readers understand the influences of early history on chemistry. About the Author Hugh W. Salzberg taught chemistry a t the Citj University of New York for 35 years and offered courses in the history of chemistry over a period of 20 years. From Caveman to Chemist reflects his dual passions for chemistry and history and his profound admiration of the great minds that developed the ideas of chemistry. Hugh W. Salzberg Editor

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to refill the generator. A civilian carpenter constructed lab benches, and we unpacked and set up the instruments and equipment. The laboratory was operating within two days of the equipment’s arrival a t the ammunition dump, and we experienced little downtime because of problems resulting from the harsh shipping conditions. The propellant analysis involved extraction with acetonitrile followed by filtration using 0.45-pm filters and subsequent analysis by HPLC (see Anal. Chem. 1991,63,475 A). We used a Hewlett-Packard 1050 HPLC system equipped with a quaternary pump, autosampler, and U V detector set a t 254 nm. An HP ChemStation was used for data processing and report generation. Stabilizer and stabilizer degradation products were analyzed and total effective stabilizer determined for each propellant lot analyzed. Based on a comparison of initial stabilizer content and the history of the stabilizer depletion rate for each lot, we were able to decide which lots should be destroyed and which were safe for shipment. Using an assembly line approach, we extracted and analyzed samples 12 hours a day, seven days a week. Unfortunately, t h e autosampler could not run unattended overnight because the generator and the fuel supplies were not reliable. Even with this limitation, during a four-week period, we analyzed 450 lots of gun propellant and determined that 15 had below acceptable levels of stabilizer. These lots were destroyed.

Concurrent with our chemical analysis, other members of the Navy’s gun propellant surveillance program began to inventory and inspect the packaging conditions of the propellants shipped to the desert. Most of the 15 lots deemed unsafe for shipping had damaged crates t h a t allowed some propellants to be exposed to the environment. We thus concluded that the propellant lots did not deteriorate as a result of harsh desert conditions unless the packaging container deteriorated or was broken. The propellent was stored in stacks on pallets in the open desert, without any shade or protection, for several months. During winter, temperatures ranged from 40 O F a t night to 70 O F during the day; during spring and summer, temperatures rose as high as 115 O F in the shade. We became concerned not so much about the short-term effects (because the data indicated that temperature was not a problem) but about the possible long-term effects of temperature cycling on propellant stability. All propellant stored in the desert has been marked so that it can be closely monitored during future stability testing. We have established a baseline for this monitoring a s a result of our on-site desert tests. Although the environment did not substantially affect the propellant’s stability, it did test the endurance of the analysts. The instrumentation was air-conditioned and resided in a reasonably sand-free environment. However, the lodging provided by the Marines posed a real challenge for two women civilians. We lived in a

300 pages (1991 ) Clothbound: ISBN 0-8412-1786-6 $24.95 Paperbound: ISBN 0-8412-1787-4 $1 4.95 American Chemical Society Distribution Office. Dept. 88 1 155 Sixteenth St.. N.W. Washington. DC 20036

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Sleeping quarters during our stay in Saudi Arabia. The Marine encampment consisted

of rows of tents with sand dunes bulldozed around them.

ANALYTICAL CHEMISTRY, VOL. 64, NO. 7, APRIL 1, 1992

tent in a temporary base camp where there were three women Marines and more than 200 male Marines. It was difficult to keep clean and wash clothes using bottled water. On most days the smoke from the burning Kuwaiti oil fields blotted out the sun and kept temperatures down to 80 O F , although d u r i n g daylight hours it could get so dark from the smoke t h a t flashlights were r e quired. When the wind shifted and the sun came out, temperatures soared to above 115 O F . Dust storms occurred frequently and coated everything with a fine powder similar to talc, unlike the coarse sand to which most Americans are accustomed. Not only were the flies tenacious, but occasionally scorpions, poisonous spiders, and vipers tried to make their home in our belongings. Because of the cultural restrictions imposed on women, we were forbidden to drive or to be unescorted in public, and our clothing had to completely cover our arms and legs. We overcame these restrictions by wear ing Marine uniforms in public and prevailing upon the male Marines and civilians to act a s our chauffeurs.

Under the harsh environmental conditions it was difficult to keep the sand out of the lab area. We vacuumed the computer every few hours in an effort to keep it clean. Sand clogged the LC pumps, and we faced the dilemma of whether to open the pumps to clean them, risking the introduction of even more sand and grit. Brownouts were frequent, and the computer and the data station malfunctioned when temperatures inside the trailer reached 90 O F . It became imperative to learn how to operate and maintain the generator. Temperature control was the greatest problem. When the s u n came out from behind the smoke, it baked the metal trailer, and inside temperatures rose to close to 100 O F despite air conditioning. This problem was mitigated by using camouflage netting over the entire trailer and operating equipment during the coolest time of day. In the end we were able to analyze the propellant and enable the Marines to load their expeditionary ships in record time. By employing a mobile lab in the desert, we proved that it is feasible to deploy a similar mobile lab elsewhere in the world.

We have designed a mobile lab that will begin operating in late spring. This lab will be used to test the stability of gun propellants stored a t various naval bases around the world. Results generated from this new facility will reduce military response times and logistical problems and at the same time increase the operational readiness of our armed forces.

Gail Y. Stine is an analytical chemist for the Indian Head Division of the Naval Suflace Waflare Center (NSWC) where she manages the Propellant Analysis Branch. She received an M.S. degree in analytical chemistry from Georgetown University and has been employed by the NSWC since 1985. She is currently developing new chromatographic methods and techniques to further characterize propellants and explosives.

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