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LIGHT METAL BOROHYDRIDES and Mg-BASED HYDRIDES for HYDROGEN STORAGE
LIGHT METAL BOROHYDRIDES AND Mg-BASED HYDRIDES FOR HYDROGEN STORAGE by SHENG GUO A thesis submitted to the University of Birmingham for the degree of DOCTOR OF PHILOSOPHY School of Metallurgy and Materials College of Engineering and Physical Sciences University of Birmingham December 2014 University of Birmingham Research Archive e-theses repository This unpublished thesis/dissertation is copyright of the author and/or third parties. The intellectual property rights of the author or third parties in respect of this work are as defined by The Copyright Designs and Patents Act 1988 or as modified by any successor legislation. Any use made of information contained in this thesis/dissertation must be in accordance with that legislation and must be properly acknowledged. Further distribution or reproduction in any format is prohibited without the permission of the copyright holder. Synopsis This work has investigated structural and compositional changes in LiBH4, Mg(BH4)2, Ca(BH4)2, LiBH4-Ca(BH4)2 during heating. The crystal and vibrational structures of these borohydrides/composites were characterized using lab-based X-ray diffraction (XRD) and Raman spectroscopy, with particular attention to the frequency/width changes of Raman vibrations of different polymorphs of borohydrides. The thermal stability and decomposition pathway of the borohydrides was studied in great detail mainly using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), in/ex situ XRD and Raman measurements, whilst the gaseous products during heating were monitored using a mass spectrometry (MS). Hydrogen is the main decomposition gaseous product from all of these compounds, but in some cases a very small amount of diborane release was also detected. -
NNL TSL Evaluations for Yttrium Hydride and Hexagonal Ice
NNL TSL Evaluations for Yttrium Hydride and Hexagonal Ice Michael Zerkle and Jesse Holmes Naval Nuclear Laboratory Cross Section Evaluation Working Group Meeting November 14-16, 2016 Brookhaven National Laboratory The Naval Nuclear Laboratory is operated for the U.S. Department of Energy and the U.S. Department of the Navy by Bechtel Marine Propulsion Corporation, a wholly owned subsidiary of Bechtel National, Inc. NNL TSL Evaluations Material MAT H(YH2) 5 Y(YH2) 55 H(ice-Ih) 10 O(ice-Ih) 50 2 YH2 Background • Yttrium hydride (YH2) is an advanced high temperature moderator • Superior hydrogen density (NH) at elevated temperatures • Keinert (1971) proposed H(YH2) TSL based on simple analytic frequency distributions • Debye-type for acoustic mode • Gaussian-type for optical mode • Higher-fidelity TSLs for H(YH2) and Y(YH2) developed using first- principles calculations • Density Functional Theory (DFT) to calculate interatomic Hellman- Feynman forces for crystal structure Hydrogen in metallic Zr, Ce, Y and Ca in equilibrium with 1 atm H at various temperatures. • Lattice Dynamics (LD) to determine 2 dispersion relations and phonon (Source: Metal Hydrides, Academic Press, p. 442, 1968) density of states (DOS) -22 NH is number of hydrogen atoms/cc x 10 3 Ab Initio Calculation of Phonon Spectra 4 YH2 Structure and Lattice Dynamics • YH2 has a CaF2 type FCC structure • 12 atoms • 4 Y atoms (blue) at vertices and faces of unit cell • 8 H atoms (grey) in tetrahedral holes between Y atoms • Dispersion relations (at right) • Well separated acoustical and optical modes • Lower branches are acoustical modes mainly due to heavy Y atom vibrations • Higher branches are optical modes mainly due to light H atom vibrations 5 YH2 Phonon Density of States 6 YH2 Phonon Density of States High resolution inelastic neutron scattering spectra from Udovic shows similar structure for YH2 centered on 0.127 eV. -
Mission to Jupiter
This book attempts to convey the creativity, Project A History of the Galileo Jupiter: To Mission The Galileo mission to Jupiter explored leadership, and vision that were necessary for the an exciting new frontier, had a major impact mission’s success. It is a book about dedicated people on planetary science, and provided invaluable and their scientific and engineering achievements. lessons for the design of spacecraft. This The Galileo mission faced many significant problems. mission amassed so many scientific firsts and Some of the most brilliant accomplishments and key discoveries that it can truly be called one of “work-arounds” of the Galileo staff occurred the most impressive feats of exploration of the precisely when these challenges arose. Throughout 20th century. In the words of John Casani, the the mission, engineers and scientists found ways to original project manager of the mission, “Galileo keep the spacecraft operational from a distance of was a way of demonstrating . just what U.S. nearly half a billion miles, enabling one of the most technology was capable of doing.” An engineer impressive voyages of scientific discovery. on the Galileo team expressed more personal * * * * * sentiments when she said, “I had never been a Michael Meltzer is an environmental part of something with such great scope . To scientist who has been writing about science know that the whole world was watching and and technology for nearly 30 years. His books hoping with us that this would work. We were and articles have investigated topics that include doing something for all mankind.” designing solar houses, preventing pollution in When Galileo lifted off from Kennedy electroplating shops, catching salmon with sonar and Space Center on 18 October 1989, it began an radar, and developing a sensor for examining Space interplanetary voyage that took it to Venus, to Michael Meltzer Michael Shuttle engines. -
Nuclear Energy: Fission and Fusion
CHAPTER 5 NUCLEAR ENERGY: FISSION AND FUSION Many of the technologies that will help us to meet the new air quality standards in America can also help to address climate change. President Bill Clinton 1 Two distinct processes involving the nuclei of atoms can be harnessed, in principle, for energy production: fission—the splitting of a nucleus—and fusion—the joining together of two nuclei. For any given mass or volume of fuel, nuclear processes generate more energy than can be produced through any other fuel-based approach. Another attractive feature of these energy-producing reactions is that they do not produce greenhouse gases (GHG) or other forms of air pollution directly. In the case of nuclear fission—a mature though controversial energy technology—electricity is generated from the energy released when heavy nuclei break apart. In the case of nuclear fusion, much work remains in the quest to sustain the fusion reactions and then to design and build practical fusion power plants. Fusion’s fuel is abundant, namely, light atoms such as the isotopes of hydrogen, and essentially limitless. The most optimistic timetable for fusion development is half a century, because of the extraordinary scientific and engineering challenges involved, but fusion’s benefits are so globally attractive that fusion R&D is an important component of today’s energy R&D portfolio internationally. Fission power currently provides about 17 percent of the world’s electric power. As of December 1996, 442 nuclear power reactors were operating in 30 countries, and 36 more plants were under construction. If fossil plants were used to produce the amount of electricity generated by these nuclear plants, more than an additional 300 million metric tons of carbon would be emitted each year. -
Fuel Geometry Options for a Moderated Low-Enriched Uranium Kilowatt-Class Space Nuclear Reactor T ⁎ Leonardo De Holanda Mencarinia,B,Jeffrey C
Nuclear Engineering and Design 340 (2018) 122–132 Contents lists available at ScienceDirect Nuclear Engineering and Design journal homepage: www.elsevier.com/locate/nucengdes Fuel geometry options for a moderated low-enriched uranium kilowatt-class space nuclear reactor T ⁎ Leonardo de Holanda Mencarinia,b,Jeffrey C. Kinga, a Nuclear Science and Engineering Program, Colorado School of Mines (CSM), 1500 Illinois St, Hill Hall, 80401 Golden, CO, USA b Subdivisão de Dados Nucleares - Instituto de Estudos Avançados (IEAv), Trevo Coronel Aviador José Alberto Albano do Amarante, n 1, 12228-001 São José dos Campos, SP, Brazil ABSTRACT A LEU-fueled space reactor would avoid the security concerns inherent with Highly Enriched Uranium (HEU) fuel and could be attractive to signatory countries of the Non-Proliferation Treaty (NPT) or commercial interests. The HEU-fueled Kilowatt Reactor Using Stirling Technology (KRUSTY) serves as a basis for a similar reactor fueled with LEU fuel. Based on MCNP6™ neutronics performance estimates, the size of a 5 kWe reactor fueled with 19.75 wt% enriched uranium-10 wt% molybdenum alloy fuel is adjusted to match the excess reactivity of KRUSTY. Then, zirconium hydride moderator is added to the core in four different configurations (a homogeneous fuel/moderator mixture and spherical, disc, and helical fuel geometries) to reduce the mass of uranium required to produce the same excess reactivity, decreasing the size of the reactor. The lowest mass reactor with a given moderator represents a balance between the reflector thickness and core diameter needed to maintain the multiplication factor equal to 1.035, with a H/D ratio of 1.81. -
Delayed Hydride Cracking in Zirconium Alloys in Pressure Tube Nuclear Reactors
IAEA-TECDOC-1410 Delayed hydride cracking in zirconium alloys in pressure tube nuclear reactors Final report of a coordinated research project 1998–2002 October 2004 IAEA-TECDOC-1410 Delayed hydride cracking in zirconium alloys in pressure tube nuclear reactors Final report of a coordinated research project 1998–2002 October 2004 The originating Section of this publication in the IAEA was: Nuclear Power Technology Development Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria DELAYED HYDRIDE CRACKING IN ZIRCONIUM ALLOYS IN PRESSURE TUBE NUCLEAR REACTORS IAEA, VIENNA, 2004 IAEA-TECDOC-1410 ISBN 92–0–110504–5 ISSN 1011–4289 © IAEA, 2004 Printed by the IAEA in Austria October 2004 FOREWORD This report documents the work performed in the Coordinated Research Project (CRP) on Hydrogen and Hydride Degradation of the Mechanical and Physical Properties of Zirconium Alloys. The Project consisted of hydriding samples of Zr-2.5 Nb pressure tube materials used in CANDU-type and RBMK reactors, the measurement of delayed hydride cracking (DHC) rates under specified conditions, and analysis of hydrogen concentrations. The project was overseen by a supervisory group of experts in the field who provided advice and assistance to the participants as required. All of the research work undertaken as part of the CRP is described in this report, which includes a review of the state of the art in understanding crack propagation by DHC and details of the experimental procedures that produced the most consistent set of DHC rates reported in an international round-robin exercise to this date. All of the participants and many of their co-workers in the laboratories involved in the CRP contributed results and material used in the drafting of this report, which contains compilations of all of the results, their analysis, discussions of their interpretation and conclusions and recommendations for further work. -
Catalytic Systems Based on Cp2zrx2 (X = Cl, H), Organoaluminum
catalysts Article Catalytic Systems Based on Cp2ZrX2 (X = Cl, H), Organoaluminum Compounds and Perfluorophenylboranes: Role of Zr,Zr- and Zr,Al-Hydride Intermediates in Alkene Dimerization and Oligomerization Lyudmila V. Parfenova 1,* , Pavel V. Kovyazin 1, Almira Kh. Bikmeeva 1 and Eldar R. Palatov 2 1 Institute of Petrochemistry and Catalysis of Russian Academy of Sciences, Prospekt Oktyabrya, 141, 450075 Ufa, Russia; [email protected] (P.V.K.); [email protected] (A.K.B.) 2 Bashkir State University, st. Zaki Validi, 32, 450076 Ufa, Russia; [email protected] * Correspondence: [email protected]; Tel.: +7-347-284-3527 i i Abstract: The activity and chemoselectivity of the Cp2ZrCl2-XAlBu 2 (X = H, Bu ) and [Cp2ZrH2]2- ClAlEt2 catalytic systems activated by (Ph3C)[B(C6F5)4] or B(C6F5)3 were studied in reactions with 1-hexene. The activation of the systems by B(C6F5)3 resulted in the selective formation of head- to-tail alkene dimers in up to 93% yields. NMR studies of the reactions of Zr complexes with organoaluminum compounds (OACs) and boron activators showed the formation of Zr,Zr- and Zr,Al-hydride intermediates, for which diffusion coefficients, hydrodynamic radii, and volumes were estimated using the diffusion ordered spectroscopy DOSY. Bis-zirconium hydride clusters of type x[Cp ZrH ·Cp ZrHCl·ClAlR ]·yRnAl(C F ) − were found to be the key intermediates of alkene 2 2 2 2 6 5 3 n dimerization, whereas cationic Zr,Al-hydrides led to the formation of oligomers. Citation: Parfenova, L.V.; Kovyazin, P.V.; Bikmeeva, A.K.; Palatov, E.R. -
Uranium (Nuclear)
Uranium (Nuclear) Uranium at a Glance, 2016 Classification: Major Uses: What Is Uranium? nonrenewable electricity Uranium is a naturally occurring radioactive element, that is very hard U.S. Energy Consumption: U.S. Energy Production: and heavy and is classified as a metal. It is also one of the few elements 8.427 Q 8.427 Q that is easily fissioned. It is the fuel used by nuclear power plants. 8.65% 10.01% Uranium was formed when the Earth was created and is found in rocks all over the world. Rocks that contain a lot of uranium are called uranium Lighter Atom Splits Element ore, or pitch-blende. Uranium, although abundant, is a nonrenewable energy source. Neutron Uranium Three isotopes of uranium are found in nature, uranium-234, 235 + Energy FISSION Neutron uranium-235, and uranium-238. These numbers refer to the number of Neutron neutrons and protons in each atom. Uranium-235 is the form commonly Lighter used for energy production because, unlike the other isotopes, the Element nucleus splits easily when bombarded by a neutron. During fission, the uranium-235 atom absorbs a bombarding neutron, causing its nucleus to split apart into two atoms of lighter mass. The first nuclear power plant came online in Shippingport, PA in 1957. At the same time, the fission reaction releases thermal and radiant Since then, the industry has experienced dramatic shifts in fortune. energy, as well as releasing more neutrons. The newly released neutrons Through the mid 1960s, government and industry experimented with go on to bombard other uranium atoms, and the process repeats itself demonstration and small commercial plants. -
Lightweight, High-Temperature Radiator for In-Space Nuclear- Electric Power and Propulsion
University of Massachusetts Amherst ScholarWorks@UMass Amherst Doctoral Dissertations Dissertations and Theses Summer November 2014 Lightweight, High-Temperature Radiator for In-Space Nuclear- Electric Power and Propulsion Briana N. Tomboulian University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/dissertations_2 Part of the Heat Transfer, Combustion Commons, Propulsion and Power Commons, and the Systems Engineering and Multidisciplinary Design Optimization Commons Recommended Citation Tomboulian, Briana N., "Lightweight, High-Temperature Radiator for In-Space Nuclear-Electric Power and Propulsion" (2014). Doctoral Dissertations. 247. https://doi.org/10.7275/5972048.0 https://scholarworks.umass.edu/dissertations_2/247 This Open Access Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. Lightweight, High-Temperature Radiator for In-Space Nuclear-Electric Power and Propulsion A Dissertation Presented by BRIANA N. TOMBOULIAN Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY September 2014 Mechanical and Industrial Engineering Department © Copyright by Briana N. Tomboulian 2014 All Rights Reserved Lightweight, High-Temperature Radiator -
1 Phys:1200 Lecture 36 — Atomic and Nuclear Physics
1 PHYS:1200 LECTURE 36 — ATOMIC AND NUCLEAR PHYSICS (4) This last lecture of the course will focus on nuclear energy. There is an enormous reservoir of energy in the nucleus and it can be released either in a controlled manner in a nuclear reactor, or in an uncontrolled manner in a nuclear bomb. The energy released in a nuclear reactor can be used to produce electricity. The two processes in which nuclear energy is released – nuclear fission and nuclear fusion, will be discussed in this lecture. The biological effects of nuclear radiation will also be discussed. 36‐1. Biological Effects of Nuclear Radiation.—Radioactive nuclei emit alpha, beta, and gamma radiation. These radiations are harmful to humans because they are ionizing radiation that have the ability to remove electrons from atoms and molecules in human cells. This can lead to the death or alterations of cells. Alteration of the cell can transform a healthy cell into a cancer cell. The hazards of radiation can be minimized by limiting ones overall exposure to radiation. However, there is still some uncertainty in the medical community about the possibility the effect of a single radioactive particle on the bottom. In other words, are the effects cumulative, or can a single exposure lead to cancer in the body. Exposure to radiation can produce either short term effects appearing within minutes of exposure, or long term effects that may appear in years or decades or even in future generations due to changes in DNA. The effects of absorbing ionizing radiation is measured in a unit called the rem. -
Synthesis, Reactivity, and Catalysis of Group 3 and Lanthanide Alkyl Complexes
Synthesis, Reactivity, and Catalysis of Group 3 and Lanthanide Alkyl Complexes By Daniel Steven Levine A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor T. Don Tilley, Co-Chair Professor Richard A. Andersen, Co-Chair Professor Alexis T. Bell Summer 2016 Abstract Synthesis, Reactivity, and Catalysis of Group 3 and Lanthanide Alkyl Complexes by Daniel Steven Levine Doctor of Philosophy in Chemistry University of California, Berkeley Professor T. Don Tilley, Co-Chair Professor Richard A. Andersen, Co-Chair Chapter 1. A series of scandium dialkyl complexes, (PNP)ScR2 (R = neopentyl, trimethylsilylmethyl), supported by the monoanionic, chelating PNP ligand (2,5- bis(dialkylphosphinomethyl)pyrrolide; alkyl = cyclohexyl, tert-butyl) was synthesized and the reactivities of these complexes toward simple hydrocarbons was investigated. The scandium– carbon bonds undergo σ-bond metathesis reactions with hydrogen and these complexes are catalysts for the hydrogenation of alkenes. Reactions with primary amines led to formation of amido complexes that undergo cyclometalation via σ-bond metathesis, without involvement of an imido complex intermediate. A variety of carbon-hydrogen bonds are also activated, including sp-, sp2-, and sp3-C–H bonds (intramolecularly in the latter case). Levine, D. S.; Tilley, T. D.; Andersen, R. A. Organometallics 2015, 34 (19), 4647. Chapter 2. Terminal group 3 methylidene complexes are generated by thermolysis of monoanionic PNP-supported scandium and yttrium dialkyl complexes. The reaction mechanism has been probed by deuterium-labeling experiments and DFT calculations. Abstraction of a γ- hydrogen from one alkyl group by the other affords a metallacyclobutane that undergoes [2+2] cycloreversion, analogous to a key step in the olefin metathesis reaction, to generate a methylidene complex and isobutene. -
The Stellarator Program J. L, Johnson, Plasma Physics Laboratory, Princeton University, Princeton, New Jersey
The Stellarator Program J. L, Johnson, Plasma Physics Laboratory, Princeton University, Princeton, New Jersey, U.S.A. (On loan from Westlnghouse Research and Development Center) G. Grieger, Max Planck Institut fur Plasmaphyslk, Garching bel Mun<:hen, West Germany D. J. Lees, U.K.A.E.A. Culham Laboratory, Abingdon, Oxfordshire, England M. S. Rablnovich, P. N. Lebedev Physics Institute, U.S.3.R. Academy of Sciences, Moscow, U.S.S.R. J. L. Shohet, Torsatron-Stellarator Laboratory, University of Wisconsin, Madison, Wisconsin, U.S.A. and X. Uo, Plasma Physics Laboratory Kyoto University, Gokasho, Uj', Japan Abstract The woHlwide development of stellnrator research is reviewed briefly and informally. I OISCLAIWCH _— . vi'Tli^liW r.'r -?- A stellarator is a closed steady-state toroidal device for cer.flning a hot plasma In a magnetic field where the rotational transform Is produced externally, from torsion or colls outside the plasma. This concept was one of the first approaches proposed for obtaining a controlled thsrtnonuclear device. It was suggested and developed at Princeton in the 1950*s. Worldwide efforts were undertaken in the 1960's. The United States stellarator commitment became very small In the 19/0's, but recent progress, especially at Carchlng ;ind Kyoto, loeethar with «ome new insights for attacking hotii theoretics] Issues and engineering concerns have led to a renewed optimism and interest a:; we enter the lQRO's. The stellarator concept was borr In 1951. Legend has it that Lyman Spiczer, Professor of Astronomy at Princeton, read reports of a successful demonstration of controlled thermonuclear fusion by R.