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Method for creating gas standards form liquid HFE-7100 and FC-72

Irwin, Adriane N.; Thornberg, Steve M.; Brown, Jason R.; Hochrein, James M.

HFE-7100 and FC-72 fluorinert are two fluids used during weapon component manufacturing. HFE-7100 is a solvent used in the cleaning of parts, and FC-72 is the blowing agent of a polymeric removable foam. The presence of either FC-72 or HFE-7100 gas in weapon components can provide valuable information as to the stability of the materials. Therefore, gas standards are needed so HFE-7100 and FC-72 gas concentrations can be accurately measured. There is no current established procedure for generating gas standards of either HFE-7100 or FC-72. This report outlines the development of a method to generate gas standards ranging in concentration from 0.1 ppm to 10% by volume. These standards were then run on a Jeol GC-Mate II mass spectrometer and analyzed to produce calibration curves. We present a manifold design that accurately generates gas standards of HFE-7100 and FC-72 and a procedure that allows the amount of each to be determined.

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TYPE SAND Report YEAR 2007
DOIOSTI

Optimizing the ASC WAN: evaluating network performance tools for comparing transport protocols

Lydick, Christopher L.

The Advanced Simulation & Computing Wide Area Network (ASC WAN), which is a high delay-bandwidth network connection between US Department of Energy National Laboratories, is constantly being examined and evaluated for efficiency. One of the current transport-layer protocols which is used, TCP, was developed for traffic demands which are different from that on the ASC WAN. The Stream Control Transport Protocol (SCTP), on the other hand, has shown characteristics which make it more appealing to networks such as these. Most important, before considering a replacement for TCP on any network, a testing tool that performs well against certain criteria needs to be found. In order to try to find such a tool, two popular networking tools (Netperf v.2.4.3 & v.2.4.6 (OpenSS7 STREAMS), and Iperf v.2.0.6) were tested. These tools implement both TCP and SCTP and were evaluated using four metrics: (1) How effectively can the tool reach a throughput near the bandwidth? (2) How much of the CPU does the tool utilize during operation? (3) Is the tool freely and widely available? And, (4) Is the tool actively developed? Following the analysis of those tools, this paper goes further into explaining some recommendations and ideas for future work.

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TYPE SAND Report YEAR 2007
DOIOSTI

The potential for imaging of in situ damage in inflatable space structures

Nellums, Robert N.

NASA is investigating the use of inflatable habitat structures for orbital transfer and planetary applications. Since space structures are vulnerable to damage from micrometeoroid and orbital debris, it is important to investigate means of detecting such damage. This study is an investigation into methods for performing non-destructive evaluation (NDE) on inflatable habitat modules. Results of this work showed that various electromagnetic imaging modalities from microwaves to terahertz imaging have the greatest potential for a viable, portable, NDE tool which could possibly be deployed aboard an inflatable habitat module.

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TYPE Conference YEAR 2007
OSTI
Results 81001–81100 of 99,299
Results 81001–81100 of 99,299