Download or read book Radiation disorder and Aperiodicity in Irradiated Ceramics written by and published by . This book was released on 1992 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final technical report documents the accomplishments of the program of research entitled Radiation Disorder and Aperiodicity in Irradiated Ceramics'' for the period June 22, 1989--June 21, 1992. This research forms the latest part on an on-going program, begun at MIT in 1983 under DOE support, which has had as its objectives investigation of the responses in radiation environments of ceramics heavily-irradiated with electrons, neutrons and ions, with potential applications to fusion energy technology and high-level nuclear waste storage. Materials investigated have included SiO2, MgAl2O4, Al23O2--N5, SiC, BeO, LiAlO2, Li2ZrO3, CaTiO3KTaO3 and Ca(Zr, Pu)Ti2O--. The program initially proposed for 1989 had as its major objectives two main thrusts: (1) research on defect aggregation in irradiated non-oxide ceramics, and (2) research on irradiation-induced amorphization of network silicas and phosphates.

Download or read book Radiation disorder and Aperiodicity in Irradiated Ceramics Final Technical Report 22 June 1989 21 June 1992 written by and published by . This book was released on 1992 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final technical report documents the accomplishments of the program of research entitled ''Radiation Disorder and Aperiodicity in Irradiated Ceramics'' for the period June 22, 1989--June 21, 1992. This research forms the latest part on an on-going program, begun at MIT in 1983 under DOE support, which has had as its objectives investigation of the responses in radiation environments of ceramics heavily-irradiated with electrons, neutrons and ions, with potential applications to fusion energy technology and high-level nuclear waste storage. Materials investigated have included SiO2, MgAl2O4, Al23O2--N5, SiC, BeO, LiAlO2, Li2ZrO3, CaTiO3KTaO3 and Ca(Zr, Pu)Ti2O--. The program initially proposed for 1989 had as its major objectives two main thrusts: (1) research on defect aggregation in irradiated non-oxide ceramics, and (2) research on irradiation-induced amorphization of network silicas and phosphates.

Download or read book Radiation induced Aperiodicity in Irradiated Ceramics written by and published by . This book was released on 1993 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experimental program is designed to reveal details of the metamict (amorphization, or crystal-to-glass) transformation in irradiated ceramics (silica compounds, less-connected lead phosphates). The silica compounds were amorphized using electrons, neutrons, and ions, while the phosphates were amorphized using ions (primarily) and neutrons. Energy-filtered electron microdiffraction, high-resoltuion transmission electron microscopy, and high-performance liquid-phase chromatography are being used.

Download or read book Radiation induced Aperiodicity in Irradiated Ceramics Progress Report 22 June 1992 1 February 1993 written by and published by . This book was released on 1993 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experimental program is designed to reveal details of the metamict (amorphization, or crystal-to-glass) transformation in irradiated ceramics (silica compounds, less-connected lead phosphates). The silica compounds were amorphized using electrons, neutrons, and ions, while the phosphates were amorphized using ions (primarily) and neutrons. Energy-filtered electron microdiffraction, high-resoltuion transmission electron microscopy, and high-performance liquid-phase chromatography are being used.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1662 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1992 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radioactive Waste Management written by and published by . This book was released on 1981 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy and Water Development Appropriations for 1995 Dept of Energy Federal Energy Regulatory Commission written by United States. Congress. House. Committee on Appropriations. Subcommittee on Energy and Water Development and published by . This book was released on 1994 with total page 2018 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Statuts provisoires de la Compagnie du Chemin de Fer Central Suisse B le written by and published by . This book was released on 1898 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Irradiation on Ceramics for Fusion reactor Applications written by and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study, coordinated with efforts of LANL and Grumman Aircraft, was to lay some basic groundwork to study the irradiation effects on the engineering properties of some useful classes of ceramic materials; ANL's efforts were pointed towards multiphase materials (glass ceramics and partially-stabilized zirconias). The materials were irradiated at 400 and 550°C to fast (E> 0.1 MeV) neutron fluences of approx. 2 x 1022n/cm2. Fluorophlogapite mica based glass ceramics (Macor, etc.) were found susceptible to weakening due to void formtion between mica plates. Composition variations within this class of glass ceramics seemed to cause sharp variations in the magnitude of the effect. Lithium silicate glass ceramic (ReX) showed sharp contrasts between the effects of ionization irradiation and displacement damage, neutron irradiation having little effect on the ReX structure while electron irradiation creating lithium silicate vitrification and rapid structural annealing.

Download or read book Toward Understanding Dynamic Annealing Processes in Irradiated Ceramics written by Michael Myers and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High energy particle irradiation inevitably generates defects in solids in the form of collision cascades. The ballistic formation and thermalization of cascades occur rapidly and are believed to be reasonably well understood. However, knowledge of the evolution of defects after damage cascade thermalization, referred to as dynamic annealing, is quite limited. Unraveling the mechanisms associated with dynamic annealing is crucial since such processes play an important role in the formation of stable post-irradiation disorder in ion-beam-processed semiconductors and determines the "radiation tolerance" of many nuclear materials. The purpose of this dissertation is to further our understanding of the processes involved in dynamic annealing. In order to achieve this, two main tasks are undertaken. First, the effects of dynamic annealing are investigated in ZnO, a technologically relevant material that exhibits very high dynamic defect annealing at room temperature. Such high dynamic annealing leads to unusual defect accumulation in heavy ion bombarded ZnO. Through this work, the puzzling features that were observed more than a decade ago in ion-channeling spectra have finally been explained. We show that the presence of a polar surface substantially alters damage accumulation. Non-polar surface terminations of ZnO are shown to exhibit enhanced dynamic annealing compared to polar surface terminated ZnO. Additionally, we demonstrate one method to reduce radiation damage in polar surface terminated ZnO by means of a surface modification. These results advance our efforts in the long-sought-after goal of understanding complex radiation damage processes in ceramics. Second, a pulsed-ion-beam method is developed and demonstrated in the case of Si as a prototypical non-metallic target. Such a method is shown to be a novel experimental technique for direct extraction of dynamic annealing parameters. The relaxation times and effective diffusion lengths of mobile defects during the dynamic annealing process play a vital role in damage accumulation. We demonstrate that these parameters dominate the formation of stable post-irradiation disorder. In Si, a defect lifetime of 6 ms and a characteristic defect diffusion length of 30 nm are measured. These results should nucleate future pulsed-beam studies of dynamic defect interaction processes in technologically relevant materials. In particular, understanding length- and time-scales of defect interactions are essential for extending laboratory findings to nuclear material lifetimes and to the time-scales of geological storage of nuclear waste. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149330

Download or read book Ion Irradiation Characterization Studies of MAX Phase Ceramics written by Daniel William Clark and published by . This book was released on 2015 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: The family of layered carbides and nitrides known as MAX phase ceramics combine many attractive properties of both ceramics and metals due to their nanolaminate crystal structure and are promising potential candidates for application in future nuclear reactors. This thesis reports on the background, design, and analysis of an experiment focused on determining the effects of energetic heavy ion irradiations on polycrystalline samples of titanium silicon carbide 312, titanium aluminum carbide 312, and titanium aluminum carbide 211. The irradiation conditions consisted of ion doses between 10 and 30 displacements per atom at temperatures of 400 and 700 degrees Celsius, conditions relevant to application in future nuclear reactors, and a relatively unexplored regime for this new class of materials known as the MAX phase. Following irradiation, a comprehensive analysis of radiation response properties was compiled using X-ray diffraction, nanoindentation, scanning electron microcopy, and transmission electron microscopy. In all cases, the materials remain fully crystalline though atomic collisions induce significant damage and disorder into the layered crystalline lattice. X-ray diffraction and nanoindentation show this damage is manifest in anisotropic swelling and hardening at all conditions and in all materials, with the aluminum based MAX phase exhibiting significantly more damage than their silicon counterpart. In all three materials there is little damage dependence on dose, suggesting saturation of radiation damage at levels below 10 displacements per atom, and a high correlation between residual damage and irradiation temperature, with significantly less damage at higher temperatures, suggesting radiation defect annealing. SEM surface analysis showed significant grain boundary cracking and loss of damage tolerance properties in the aluminum based MAX phase irradiated at 400 degrees Celsius, but not in the silicon counterpart. TEM analysis of select samples suggest that interstitials are highly mobile while vacancies are immobile and that all three materials are in the so-called point defect swelling regime between 400 and 700 degrees Celsius. All results are consistent with previous work involving traditional and MAX phase ceramics. Results show that the aluminum MAX phase are not fit for application near 400 degrees Celsius and that the silicon MAX phase is overall more damage tolerant.

Download or read book Advances in Materials Science for Environmental and Energy Technologies II written by Josef Matyáš and published by John Wiley & Sons. This book was released on 2013-08-12 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings contains a collection of 24 papers from five 2012Materials Science and Technology (MS&T’12)symposia. Green Technologies for Materials Manufacturing and ProcessingIII Materials Development for Nuclear Applications and ExtremeEnvironments Materials Issues in Nuclear Waste Management in the21st Century Energy Conversion – Photovoltaic, Concentrating SolarPower, and Thermoelectric Energy Storage: Materials, Systems and Applications

Download or read book Irradiation Spectrum and Ionization induced Diffusion Effects in Ceramics written by and published by . This book was released on 1997 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are two main components to the irradiation spectrum which need to be considered in radiation effects studies on nonmetals, namely the primary knock-on atom energy spectrum and ionizing radiation. The published low-temperature studies on Al2O3 and MgO suggest that the defect production is nearly independent of the average primary knock-on atom energy, in sharp contrast to the situation for metals. On the other hand, ionizing radiation has been shown to exert a pronounced influence on the microstructural evolution of both semiconductors and insulators under certain conditions. Recent work on the microstructure of ion-irradiated ceramics is summarized, which provides evidence for significant ionization-induced diffusion. Polycrystalline samples of MgO, Al2O3, and MgAl2O4 were irradiated with various ions ranging from 1 MeV H to 4 MeV Zr ions at temperatures between 25 and 650°C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructural of the irradiated specimens. Dislocation loop nucleation was effectively suppressed in specimens irradiated with light ions, whereas the growth rate of dislocation loops was enhanced. The sensitivity to irradiation spectrum is attributed to ionization-induced diffusion. The interstitial migration energies in MgAl2O4 and Al2O3 are estimated to be d".4 eV and d".8 eV, respectively for irradiation conditions where ionization-induced diffusion effects are expected to be negligible.

Download or read book A Table Shewing the Exact Value of the Several Forts of Cane Chairs written by and published by . This book was released on 1689* with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: