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Journal of Research of the National Institute of Standards and Technology

Electron diffraction using transmission electron microscopy

Electron diffraction using transmission electron microscopy Leonid A. Bendersky Electron diffraction via the transmission electron microscope is a powerful method for characterizing the structure of materials, including perfect crystals and defect structures. The advantages of electron diffraction over other methods, e.g., x-ray or neutron, arise from the extremely short wavelength ([approximately equal to]2 pm), the […]

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Journal of Research of the National Institute of Standards and Technology

NIST GRANTED PATENT FOR A COMPACT COMPRESSOR FOR POLARIZED [He.sup.3] GAS – National Institute of Standards and Technology

NIST GRANTED PATENT FOR A COMPACT COMPRESSOR FOR POLARIZED [He.sup.3] GAS – National Institute of Standards and Technology – Brief Article By using optical methods, it is possible to align the magnetic moments of 3He nuclei with an applied magnetic field producing “polarized [He.sup.3] gas.” Since its first production about 40 years ago, polarized [He.sup.3] […]

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Journal of Research of the National Institute of Standards and Technology

a correction to the heat defect calculations

Water calorimetry: a correction to the heat defect calculations Norman V. Klassen In a recent publication, we used a reaction. model (model III) to calculate the heat defect for the irradiation of aqueous solutions with ionizing radiation at 21 [degrees]C. Subsequent work has revealed that the literature value used for one of the rate constants […]

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Journal of Research of the National Institute of Standards and Technology

Prototype of flexible ball step gauge artifact – News Briefs – National Institute of Standards and Technology, Air Force develop standardized gauge for coordinate measuring machines

Prototype of flexible ball step gauge artifact – News Briefs – National Institute of Standards and Technology, Air Force develop standardized gauge for coordinate measuring machines – Brief Article As part of the program to maintain quality control on coordinate measuring machines (CMMs) for the Air Force, NIST completed a prototype ball step gauge artifact. […]

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Journal of Research of the National Institute of Standards and Technology

X-ray microanalysis in the variable pressure scanning electron microscope

X-ray microanalysis in the variable pressure scanning electron microscope – environmental Dale E. Newbury Electron-excited x-ray microanalysis performed in the variable pressure and environmental scanning electron microscopes is subject to additional artifacts beyond those encountered in the conventional scanning electron microscope. Gas scattering leads to direct contributions to the spectrum from the environmental gas, as […]

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Journal of Research of the National Institute of Standards and Technology

Preparation and comprehensive characterization of a calcium hydroxyapatite reference material

Preparation and comprehensive characterization of a calcium hydroxyapatite reference material Milenko Markovic Numerous biological and chemical studies involve the use of calcium hydroxyapatite (HA), [Ca.sub.10](P[O.sub.4])[.sub.6](OH)[.sub.2]. In this study detailed physicochemical characterization of HA, prepared from an aqueous solution, was carried out employing different methods and techniques: chemical and thermal analyses, x-ray diffraction, infrared and Raman […]

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Journal of Research of the National Institute of Standards and Technology

Mathematics and measurement

Mathematics and measurement Ronald F. Boisvert In this paper we describe the role that mathematics plays in measurement science at NIST. We first survey the history behind NIST’s current work in this area, starting with the NBS Math Tables project of the l930s. We then provide examples of more recent efforts in the application of […]

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Journal of Research of the National Institute of Standards and Technology

Papers and posters presented at the April 2004 International Conference on Precision Measurements with Slow Neutrons at the National Institute of Standards and Technology

Papers and posters presented at the April 2004 International Conference on Precision Measurements with Slow Neutrons at the National Institute of Standards and Technology Muhammad Arif Preface This Special Issue of the Journal of Research of the National Institute of Standards and Technology (Parts 1 and 2) contains papers from the International Conference on Precision […]

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Journal of Research of the National Institute of Standards and Technology

Step Part 28 Workshop Held At Nist – Standard for the Exchange of Product model data – National Institute of Standards and Technology

http://www.looksmart.com/ http://www.findarticles.com/ FindArticles > Journal of Research of the National Institute of Standards and Technology > Nov, 2000 > Article > Print friendly Step Part 28 Workshop Held At Nist – Standard for the Exchange of Product model data – National Institute of Standards and Technology – Brief Article Technical experts from the United States […]

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Journal of Research of the National Institute of Standards and Technology

A Software Tool For Generation Of Monsel Libraries

A Software Tool For Generation Of Monsel Libraries – Brief Article A means of simulating electron trajectories and secondary generation in scanning electron microscope samples is an essential piece of the library-based linewidth measurement system being developed under contract with SEMATECH. The NIST code for doing this, called “MONSEL,” has some important advantages compared to […]