Engineering topics

Wacker, John F.

Publications and source records attributed to Wacker, John F..

3 records

DOE OSTI2021

Tracking and Protecting High-Value/High-Visibility Assets

Pacific Northwest National Laboratory’s (PNNL’s) Independent Oversight (IO) office led an assessment to evaluate PNNL’s approach to tracking and protecting high-value/high-visibility assets. The approach used by the assessment team included a review of requirements (including records), staff interviews, on-site and virtual walkthroughs of lab spaces, review of data, and the development of three separate workflows to capture PNNL’s current practices in the areas of controlled substances, select toxins, and precious metals. Summary results are provided within the report, including all findings and opportunities for improvement (OFIs).

99 GENERAL AND MISCELLANEOUS↗

NASA NTRS1989

Laboratory simulation of meteoritic noble gases. III - Sorption of neon, argon, krypton, and xenon on carbon - Elemental fractionation

The sorption of Ne, Ar, Kr, and Xe was studied in carbon black, acridine carbon, and diamond in an attempt to understand the origin of trapped noble gases in meteorites. The results support a model in which gases are physically adsorbed on interior surfaces formed by a pore labyrinth within amorphous carbons. The data show that: (1) the adsorption/desorption times are controlled by choke points that restrict the movement of noble gas atoms within the pore labyrinth, and (2) the physical adsorption controls the temperature behavior and elemental fractionation patterns.

Wacker, John F.↗

NASA NTRS1987

Interstellar diamonds in meteorites

Primitive meteorites contain up to 400 ppm of a very fine-grained type of carbon tentatively called C-delta. Evidence is presented here that part of all of the C-delta is primary, not shock-produced, diamond formed by stellar condensation as a metastable phase. It appears that interstellar dust contains diamond.

Lewis, Roy S.↗