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Milenski, Helen Marie

Publications and source records attributed to Milenski, Helen Marie.

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Cheesecloth Alternatives Testing

Heat source plutonium oxide (HS-PuO 2 ) enriched with 65% or greater plutonium-238, is recovered and purified using an aqueous nitric acid process. Historically, cheesecloth has been employed for small spill clean-up and for routine housekeeping. However, the 2016 Department of Energy (DOE) Operating Experience report, entitled Nitrate Waste Evaluations, stated that the mixing of nitrate wastes with organic absorbents, such as cheesecloth, may render transuranic waste unacceptable for disposal at WIPP in the future. This report explores the feasibility of replacement of cheesecloth with an alternative sorbent wipe that has similar absorption and cleaning abilities and improved acid resistance. Currently, cheesecloth is used for three different functions in HS-PuO 2 operations: spill cleanup; general housekeeping operations such as cleaning glovebox floors and windows, balances, furnaces, etc.; and decontamination of iridium cladded heat sources containing HS-PuO 2 . Alternatives used for spill cleanup must be able to tolerate high neutron doses found in the HS-Pu gloveboxes. They must also be able to withstand exposure to nitric acid concentrations up to 15.8 M without decomposing. Wipes used for general housekeeping must also be durable enough to clean rough surfaces and remain intact when used for scrubbing. Wipes used for clad decontamination do not need to absorb large amounts of liquid but they must be able to withstand neutron exposures, temperatures of up to several hundred degrees Celsius, and exposure to acid solutions followed by mild scrubbing. Finally wipes used for any purpose must resist chemical reactions with nitric acid that could cause issues for waste disposal such as energetic exothermic reactions or flammable gas build-up. The wipes selected for this study were ranked based on their usability (radiation tolerance, absorbency, integrity in nitric acid, and durability) as well as their chemical compatibility with nitric acid as demonstrated using several types of chemical analyses. Wipes were then ranked based on the combination of their usability and chemical compatibility scores.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Stainless Steel Corrosion Studies Final Report: FY17 End of-Year

Two materials are being considered in applications requiring their contact against stainless steel surfaces. These materials include the solvent methyl ethyl ketone (MEK), and the polymer neoprene (polychloroprene). There is concern that contact of these materials with stainless steel substrates may lead to corrosion. To address these concerns we have undertaken corrosion studies under conditions expected to be more aggressive than in intended applications. These conditions include elevated temperature and humidity, and submersion and suspension in solvent vapors, in an attempt to accelerate any potential deleterious interactions. Corrosion rates below 0.1 mpy have historically been deemed INSIGNIFICANT from a WR Production standpoint; corresponding guidelines for non-production applications are lacking.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Comparative Assessment of Copper-Coated Kapton: Analysis of Microclad from Several Manufacturing Lots

Microclad is a composite material consisting of a thin copper coating applied on a single side over a Kapton substrate. Kapton is the commercial designator for polyimide supplied by DuPont. Microclad is a key material in detonator manufacture and function. Detonators which utilize Microclad function when a large current applied through a thin bridge etched into the copper produces a plasma, accelerating a Kapton flyer into an explosive (PETN) pellet. The geometry and properties of the Microclad are a critical element of this process.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Technical Assistance for Remote Sensor Placement Related Projects for Structural Health Monitoring

The world’s infrastructure is aging and many aspects are cost prohibitive to replace or even repair unless critically necessary. The standard way of determining if these repairs are critical or not is usually dependent on trained visual individual inspection. This process is very time consuming and costly considering the large areas and various structures that need to be monitored. A cost effective solution to this problem is to be able to monitor structures, such as roads, buildings, and bridges with remote sensors. Developing this solution provides some unique challenges such as sensor placement, types of sensors, energy needs for placed sensors, and data retrieval. As for the aspect of sensor placement, one method is to fly semi-autonomous Unmanned Arial Vehicles (UAVs) loaded with a sensor deployment mechanism to the structures so as to place the sensor and perhaps retrieve data from previously placed sensors as well. Many tests need to be run to determine the best UAV structure and deployment system to fulfill this task. It is hoped that through a multidisciplinary engineering scope the most effective process of monitoring the aging infrastructure can be developed.

42 ENGINEERING↗