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Projects/Programs

Displaying 1 - 25 of 59

Advanced Dimensional Measurement Systems

Ongoing
New dimensional measurement technologies provide significant benefits to industry such as increasing measurement throughput, enabling new manufacturing process (such as additive manufacturing) and providing more detailed part information for manufacturing process improvement. However, before

Advanced Metering in Smart Distribution Grids

Completed
Objective: To advance measurement science for the performance of smart meters and associated metering standards and test procedures that will enable accurate and fair electricity metering needed for the smart grid, by 2016. What is the new technical idea? This project will develop test procedures

Aperture area measurements

Ongoing
Aperture area measurements are performed at NIST’s aperture area measurement facility, which combines a precise interferometric motion stage with high-resolution optical microscopy. This non-contact method is especially well suited for the measurement of defining apertures with knife edges that are

Basic Metrology (Archive): New Standardization of Ra-228

Completed
Radium-228 has a half-life of (5.75 years) and decays by emitting a beta particle. It is a radioactive decay product in the thorium-232 decay series, a very difficult and complex decay chain: 232Th→ 228Ra → 228Ac → 228Th → 224Ra → 220Rn → 216Po → 212Pb → 212Bi → 208Tl → 208Pb(stable); with a sub

Basic Metrology: High-Dose Dosimetry Uncertainty Tables

Ongoing
Gammacell™ Calibration Geometry Dose Rate Uncertainty Source Type A (%) Type B (%) Water Calorimetry in Vertical Beam 0.16 0.51 Gammacell/Pool Source Ratio Data 0.10 Pool/B036 Source Ratio Data 0.17 Geometry Correction Factor 0.11 Field Uniformity 0.01 Source Timer (irrad time > 8min) 0.20 Co-60

Basic Metrology: Standard Reference Data on Radiation Interactions

Ongoing
This work continues in the Division's Photon and Charged-Particle Data Center. The compilations of the Data Center rely heavily on evaluating measurements and on their synthesis with available theory to extend the data and provide for comprehensive coverage over broad ranges of energy and materials

Calibration of Force Transducers

Ongoing
The calibration report describes the relationship between the applied force and the measured deformation, either in electrical or mechanical units. A transducer can be calibrated using (1) a readout device furnished by the customer, in which case the transducer and the readout device are calibrated

Calibration Services: High-Dose Dosimetry

Ongoing
NIST developed the alanine dosimetry system in the early 1990's to replace radiochromic dye film dosimeters. Later in the decade the alanine system was firmly established as a transfer service for high-dose radiation dosimetry and an integral part of the internal calibration scheme supporting these

Calibration Services: Low-Energy Photon Brachytherapy Sources

Ongoing
Since 1999, over 1,500 seeds of more than 40 different designs from 18 manufacturers have been calibrated using the WAFAC. On-site characterization at seed manufacturing plants for quality control, as well as at therapy clinics for treatment planning, relies on well-ionization chamber measurements

Calibration Services: New Calibration Facility for X-Ray Air Kerma

Ongoing
The NIST x-ray calibration facility is composed of a suite of rooms that includes the 11 m by 7 m calibration range, a dedicated equipment room, connected by custom shielding ports for communication with the x-ray tubes in the radiation area, an operator control center with a viewing window and

Calibrations: Neutron Device Calibrations

Ongoing
The Neutron Physics Group calibrates neutron radiation detectors used for personnel protection and irradiates personnel dosimeters in standard neutron fields. The fields are produced by unmoderated 252Cf and 252Cf moderated with a D 2O sphere (represented by the gray sphere near the center of the

Calibrations: Neutron Source Strength

Ongoing
Calibrations are performed using the manganous sulfate bath technique in which the emission rate of the source to be calibrated is compared to the emission rate of NBS–1, the national standard Ra–Be photo-neutron source. Neutron source calibrations typically have a relative expanded uncertainty ( k

Color and appearance

Ongoing
The quality of an object—be it fruit at the grocery store, clothes in the department store, or a new car on the dealer's lot—is often judged by its color and appearance. Appearance greatly influences a customer's judgement of the quality and acceptability of manufactured products, as yearly there is

Comparisons (Archive): International Comparison of Tc-99 Activity

Completed
Measurements by NIST on the solution were performed by three methods: viz., liquid scintillation (LS) standardizations (with 3H-standard efficiency tracing); with triple-to-double-coincidence ratio (TDCR) method; and with by 4ηβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) measurements. Impurities