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Moore, R. C.

Publications and source records attributed to Moore, R. C..

8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Tin(II)apatite: Synthesis, Characterization, and Challenge with Pertechnetate - 16194

We will report on the synthesis of stannous apatite and the subsequent reductive capacity attained, using a cerium (IV) titration method. Also reported will be the distribution coefficients derived using a Hanford tank supernatant simulant of 7.8 M sodium with chrome (VI) as a contaminant of concern, as a potential non-isotopic oxy-anion and technetium surrogate for reductive capacity determinations. Pertechnetate will be subjected to reduction using hydroxylamine, glucose and threose. The purpose is to take the first step in laboratory analyses to determine the amount of non-pertechnetate species in Hanford tank waste. A proposed sequestration mechanism will be presented as to why the reacted tin(II)apatite does not release technetium once reacted. SEM and EDS spectra will be presented on the crystalline apatite. Areas of incorporation of the tin(II)apatite will be presented for the Hanford tank waste process. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1985

Historical Cost Curves for Hydrogen Masers and Cesium Beam Frequency and Timing Standards

Historical cost curves were developed for hydrogen masers and cesium beam standards used for frequency and timing calibration in the Deep Space Network. These curves may be used to calculate the cost of future hydrogen masers or cesium beam standards in either future or current dollars. The cesium beam standards are decreasing in cost by about 2.3% per year since 1966, and hydrogen masers are decreasing by about 0.8% per year since 1978 relative to the National Aeronautics and Space Administration inflation index.

Remer, D. S.↗
NASA NTRS1977

Open loop digital frequency multiplier

An open loop digital frequency multiplier is described which has a multiplied output synchronized to low frequency clock pulse. The system includes a multistage digital counter which provides a pulse output as a function of an integer divisor. The integer divisor and the timing or counting cycle of the counter are interrelated to the frequency of a clock input. The counting cycle is controlled by a one shot multivibrator which, in turn, is driven by a reference frequency input.

Moore, R. C.↗
NASA NTRS1977

Open-loop digital frequency multiplier

Monostable multivibrator is implemented by using digital integrated circuits where multiplier constant is too large for conventional phase-locked-loop integrated circuit. A 400 Hz clock is generated by divide-by-N counter from 1 Hz timing reference.

Moore, R. C.↗