Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 26 for “"X-ray spectrometer"”.
-
An x-ray spectrometer determination of retained austenite in steel
Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Metallurgy, 1952
-
Upgrade of the neon soft X-ray spectrometer for Alcator C-Mod
… temperature, and impurity density, a Neon Soft X-ray Spectrometer (NeSoXs) was installed on the Alcator C-Mod tokamak. This spectrometer used a spherically bent mica crystal as the reflective element in order to separate the spectral and spatial information on the receiving CCD. The original …
-
Radiation management, avionics development, and integrated testing of a Class-D space-based asteroid X-ray spectrometer
The Regolith X-ray Imaging Spectrometer (REXIS) is a student designed and built payload instrument aboard NASA's OSIRIS-REx asteroid sample return mission. The interplanetary target for this mission is a primitive asteroid known as Bennu that is believed to be relatively unchanged since the …
-
I. X-Ray Analysis of Foundry Dusts in Relation to Silicosis and Siderosisii. Application of a New X-Ray Spectrometer to the Analysis of Highly Hydrated Dolomitic Lime Iii. A Critical Study of Instrumental Methods of Evaluation of Oil Film Strengths and Stabilities
Made available in DSpace on 2014-12-05T19:35:45Z (GMT). No. of bitstreams: 1 0004460.pdf: 5943080 bytes, checksum: 6fd91a982a2396463bd12e43c8862695 (MD5) Previous issue date: 1952
-
The L- to H-mode transition and momentum confinement in Alcator C-Mod plasmas
Using a spatially-resolving x-ray spectrometer system, toroidal impurity rotation in Alcator C-Mod plasmas was measured. The propagation of the rotational velocity from the edge to the core of the plasma column was measured during the L- to H-mode transition. Momentum transport was measured in both …
-
Identification and evolution of quantities of interest for a stochastic process view of complex space system development
… to CASTOR, the preliminary design of the REXIS x-ray spectrometer provides the foundation for applying stochastic process approaches during the early phases of system development. Lastly, a spacecraft panel structural dynamics experiment is presented that illustrates analysis techniques commonly …
-
Interaction of stainless steel threaded fasteners with stainless steel locking inserts
… microscope coupled with an Energy Dispersive X-ray Spectrometer. Since high-vacuum environment applications require very limited use (if any) of lubrication for threaded fastening systems, galling between the threaded fastener and the locking insert was determined to be the major concern. …
-
Radiation Damage Analysis of the Swept Charge Device for the C1XS Instrument
… charge coupled device (CCD), for use in the Chandrayaan-1 X-ray Spectrometer (C1XS). C1XS, launched onboard Chandrayaan-1, was designed to detect the X-ray fluorescence, caused by solar flares, from the lunar surface. To ensure the instrument was a success a radiation damage study was performed, …
-
Global momentum confinement times in Alcator C-Mod H- and I- regime plasmas
Using a spatially-resolving x-ray spectrometer system, the toroidal rotation velocity in Alcator C-Mod plasmas is measured and analyzed. At the L-H and L-I transition, there is a co-current movement in the toroidal rotation velocity.The propagation of this rotational velocity from the edge to the …
-
Phase equilibrium investigations of the Adirondack Class basalts from the Gusev plains, Gusev crater, Mars
… site on Mars, determined by the Alpha Particle X-ray Spectrometer on the Spirit Rover (Gellert et al., 2006; McSween et al., 2006). The near-liquidus phase relations were determined over the pressure range of 0.1 MPa to 1.5 GPa and at temperatures from 1105 °C to 1390 °C in a piston cylinder …
-
Chemistry and the Automotive Industry
… by database and internal Energy Dispersive X-ray Fluorescence (XRF) screening, third party laboratory material testing, and the future of the chemist in the United States (U.S.) automotive industry. The third party testing was performed at Western Kentucky University (WKU) via the Materials …
-
Preparation of glass-ceramics largely using steelmaking slags and study on the effect of iron content on properties of glass-ceramics
… agent to recover iron in raw materials. X-ray diffraction analysis (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray spectrometer (EDX) were used to study the microstructure of glass-ceramics formed. Bending …
-
Application of Bayesian-based uncertainty and global sensitivity analyses to spacecraft thermal design
… design methods are applied to the REgolith X-ray Imaging Spectrometer (REXIS), a student built x-ray spectrometer aboard NASA's OSIRIS-REx mission. Uncertainty analysis shows the area of the main instrument's radiator could have been reduced by 11%, as compared to the design obtained from …
-
Improving the design process of the REgolith X-ray Imaging Spectrometer with model-based systems engineering
… historical development of the REgolith Imaging X-ray Spectrometer (REXIS), a student-built instrument on the OSIRIS-REx asteroid sample return mission, against a hypothetical development timeline that incorporates information from system models. The system models, constructed in SysML, capture the …
-
Novel X-Ray and Antinucleus Searches for Dark Matter
… into Standard Model particles, particularly x-rays and antinuclei. A variety of DM candidate particles are expected to decay or annihilate into x-ray photons, which can be detected by space-based telescopes. For example, keV-scale sterile neutrinos arise in many new-physics scenarios, and their …
-
Theoretical and Experimental Studies of Radiation from Z-Pinch Complex Wire Arrays and Applications
… particular a newly developed time-gated hard x-ray spectrometer to gain an understanding as to how these plasmas radiate in time, particularly in the 0.7 - 4.4 Å range. The experiments predominately took place on the 1.7 MA Zebra generator at the Nevada Terawatt Facility (NTF) at the University …
-
Experimental study of plasma transport using X-ray imaging spectroscopy in Alcator C-Mod
The high resolution X-ray spectrometer with spatial resolution (HiReX-Sr) is intensively used in the studies of impurity, momentum and energy transport in Alcator C-Mod. This thesis investigates three phenomena using HiReX-Sr: (1) Non-local heat transport (the breakdown of a local expression for …
-
High-temperature corrosion study of alloys in molten MgCl₂-KCl eutectic salt
… (SEM) equipped with an energy dispersive X-ray spectrometer (EDS). Secondly, the effect of Ni on the corrosion behavior of the alloys is studied in this research. When the alloy is connected with Ni, the corrosion rate is higher than that without connection in the same condition. Thirdly, …
-
Mechanical design, calibration, and environmental protection of the REXIS DAM
The REgolith X-ray Imaging Spectrometer (REXIS) is a joint effort by MIT and Harvard to build the student-collaboration experiment aboard OSIRIS-Rex, an asteroid sample return mission sponsored by the NASA New Frontiers program. OSIRISREx is scheduled to launch to near-Earth asteroid Bennu in 2016. …
-
Enhanced Field Emission Studies on Nioboim Surfaces Relevant to High Field Superconducting Radio-Frequency Devices
… SEM chamber equipped with an energy-dispersive x-ray spectrometer for individual emitting site characterization. Compared to other systems built for similar purposes, this apparatus has low cost and maintenance, high operational flexibility, considerably bigger scan area, as well as reliable …
Page 1 of 2