The University of New Mexico has undertaken a study to determine the effects of radiation on Quantum Dot Photonic Integrated Circuits (QDPICs). Over the course of the last year, the constituent III-V active semiconductor materials and Si-photonic components forming these QDPICs have been designed, grown and fabricated. Photoluminescence studies before and after radiation exposure have been conducted on bare wafer samples for the III-V quantum-confined laser materials to isolate the damage to the active semiconductor materials themselves. Further techniques to probe radiation damage at the wafer level have been highlighted as well as methods to assess performance degradation at the device level. These studies should pave the way towards the quantitative assessment of the survivability of next-generation multi-cell processors based on optical interconnects.

关键词：光致发光；量子点；辐射损伤；降解

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This study focuses on the feasibility of using solar energy on Department of Defense (DoD) installations located throughout the Middle East. These DoD installations are currently using electricity generated from the local power grid at commercial rates, or generated by contractor-provided diesel generators. As an alternative, the effective use of solar energy may result in considerable savings and operational efficiency. In contrast to oil prices, the cost of renewable energy has been declining rapidly in recent years. The cost of solar panels, for example, has decreased by more than 60 percent since 2009 (Reichart, 2011). The aim of this paper is to carry out an analysis of the use of solar photovoltaic (PV) panels at DoD installations with respect to their cost-effectiveness in installation, operation, maintenance, security, sustainability, and reliability. We will examine meteorological data that provide the average monthly sunlight levels for different geographical areas, information on the effectiveness of the commercial solar PV panels currently available, electricity consumption levels for DoD installations at different times of the day, and current cost structures. Noneconomic attributes of solar installations also need to be considered to properly assess the feasibility of solar power as a substitute for current sources of electricity. The research is limited to evaluating the feasibility of using solar PV panels for electricity generation in forward operating bases. We have analyzed a trend in levelized cost of electricity (LCOE) for solar PV panels and have come to the conclusion that solar PV panels will become competitive with grid energy around 2020, provided that current growth projections in installed capacity and a corresponding decrease in the cost of solar PV-generated electricity continue. In light of our findings, we are confident that solar PV has the potential to compete with grid electricity in the near future.

关键词：成本效益；电力生产；光伏效应；可再生能源

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The work documented in this report was performed under the Fuel Cycle Research and Development (FCRD) Programs Advanced Fuels Campaign (AFC) FY13 Work Package Number FT-13OR020222, revision 0, Route to production and qualification of FCM fuel - ORNL. The sole milestone in this work package is M2FT-13OR0202221, Report Documenting Production Process, Thermophysical Properties, and QA Process to be Applied to First Irradiation Batch of FCM Fuels, due July 27, 2013. This report satisfies that milestone. As described in Section 1.1 the overall purpose of this document is to provide a bridging Quality Assurance (QA) document internal to the FCRD program enabling the irradiation of test articles of interest to the program. These articles are to be fabricated at the Oak Ridge National Laboratory (ORNL) and passed to the Idaho National Laboratory (INL) for irradiation in the Advanced Test Reactor (ATR) as part of the Accident Tolerant Fuel (ATF) development effort designated the ATF-1 Test Series. These test articles include fully ceramic matrix fuel in zirconium alloy clad, as well as other potential fuel-clad systems under development including advanced steel clad and silicon carbide composite clad. The advance steel and SiC test rodlets will each contain commercial UO2 fuel. In each case these irradiation campaigns will represent first-time irradiation for these materials with experimental goals being irradiation stability, both in terms of dimensional stability and thermo-physical properties, as well as fuel-clad interaction. It is anticipated that post-irradiation evaluation will be carried out at hot-cell facilities at both the INL and ORNL with relevant information provided in this and other reports. This document specifically provides a high-level description of these test articles and a more rigorous description on the control and QA processes to be followed during the production of these articles.

关键词：核燃料；反应堆事故；ATR反应器；燃料循环

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We investigated the activity and stability of n=(1, 2, 3) platinum layers supported on a number of rutile metal oxides (MO2; M=Ti, Sn, Ta, Nb, Hf and Zr). A suitable oxide support can alleviate the problem of carbon corrosion and platinum dissolution in Pt/C catalysts. Moreover, it can increase the activity of platinum if the interaction between the support and the metal is optimal. We found that both the activity and the stability depend on the number of platinum layers and, as expected, both converge toward platinum bulk values if the number of layers is increased. With use of a simple volcano curve for activity estimation, we found that the supported platinum layers could be active for the oxygen reduction reaction, with a few candidates possibly having an activity even greater than that of platinum. Furthermore, we established a correlation between stability and activity for supported platinum monolayers, which suggests that activity can be increased at the expense of stability and vice versa. Finally, the performance of the systems was evaluated against Pt(111) skins on Pt3X (X=Ni, Co, Fe, Ti, Sc and Y) alloys, which are the best catalysts known to date for the reaction.

关键词：金属氧化物；铂；质子；燃料电池；膜；催化剂

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The goal of this paper is to relate numerical dissipations that are inherited in high order shock-capturing schemes with the onset of wrong propagation speed of discontinuities. For pointwise evaluation of the source term, previous studies indicated that the phenomenon of wrong propagation speed of discontinuities is connected with the smearing of the discontinuity caused by the discretization of the advection term. The smearing introduces a nonequilibrium state into the calculation. Thus as soon as a nonequilibrium value is introduced in this manner, the source term turns on and immediately restores equilibrium, while at the same time shifting the discontinuity to a cell boundary. The present study is to show that the degree of wrong propagation speed of discontinuities is highly dependent on the accuracy of the numerical method. The manner in which the smearing of discontinuities is contained by the numerical method and the overall amount of numerical dissipation being employed play major roles. Moreover, employing finite time steps and grid spacings that are below the standard Courant-Friedrich-Levy (CFL) limit on shockcapturing methods for compressible Euler and Navier-Stokes equations containing stiff reacting source terms and discontinuities reveals surprising counter-intuitive results. Unlike non-reacting flows, for stiff reactions with discontinuities, employing a time step and grid spacing that are below the CFL limit (based on the homogeneous part or non-reacting part of the governing equations) does not guarantee a correct solution of the chosen governing equations. Instead, depending on the numerical method, time step and grid spacing, the numerical simulation may lead to (a) the correct solution (within the truncation error of the scheme), (b) a divergent solution, (c) a wrong propagation speed of discontinuities solution or (d) other spurious solutions that are solutions of the discretized counterparts but are not solutions of the governing equations. The present investigation for three very different stiff system cases confirms some of the findings of Lafon; Yee (1996) and LeVeque; Yee (1990) for a model scalar PDE. The findings might shed some light on the reported difficulties in numerical combustion and problems with stiff nonlinear (homogeneous) source terms and discontinuities in general.

关键词：不连续；耗散；反应流；截断误差；非平衡流动

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Seamless integration of distributed/renewable energy into a smart MicroGrid architecture is a hot topic of research for both public and defense applications. It is the DoD's intention to develop a more cost efficient and reliable power architecture on the battlefield. A smart MicroGrid seamlessly integrates an array of locally installed, distributed power sources and couples them using advanced control schemes to improve the reliability at the sources' point of common coupling. These islanded grids must be capable of powering a wide range of conventional and advanced loads including climate control systems, lights, communication systems, and high pulsed power systems such as radars, high power microwave (HPM) weapons, or electromagnetic launchers among others. The latter types of loads draw rapid high power bursts of energy from the grid and are typically powered using their own dedicated power supplies. The impact this type of loading has on the central DC or AC bus of a MicroGrid must be studied and it was the intent of this research to better understand how operation of these advanced loads impacts the quality of the voltage on the main bus of a MicroGrid.

关键词：电流；电力负荷；储能；电压；发电机

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Advances in the understanding of multiphase flow characteristics under variable gravity conditions will ultimately lead to improved and as of yet unknown process designs for advanced space missions. Such novel processes will be of paramount importance to the success of future manned space exploration as we venture into our solar system and beyond. In addition, because of the ubiquitous nature and vital importance of biological and environmental processes involving airwater mixtures, knowledge gained about fundamental interactions and the governing properties of these mixtures will clearly benefit the quality of life here on our home planet. The techniques addressed in the current research involving multiphase transport in porous media and gas-liquid phase separation using capillary pressure gradients are also a logical candidate for a future International Space Station (ISS) flight experiment. Importantly, the novel and potentially very accurate Lattice-Boltzmann (LB) modeling of multiphase transport in porous media developed in this work offers significantly improved predictions of real world fluid physics phenomena, thereby promoting advanced process designs for both space and terrestrial applications.This 3-year research effort has culminated in the design and testing of a zero-g demonstration prototype. Both the hydrophilic (glass) and hydrophobic (Teflon) media Capillary Pressure Gradient (CPG) cartridges prepared during the second years work were evaluated. Results obtained from ground testing at 1-g were compared to those obtained at reduced gravities spanning Martian (13-g), Lunar (16-g) and zero-g. These comparisons clearly demonstrate the relative strength of the CPG phenomena and the efficacy of its application to meet NASAs unique gas-liquid separation (GLS) requirements in non-terrestrial environments.LB modeling software, developed concurrently with the zero-g test effort, was shown to accurately reproduce observed CPG driven gas-liquid separation phenomena. The design and fabrication of a micropost plate-lamina Hele-Shaw (HS) cell was performed which served as a computationally attainable geometric structure facilitating direct comparison between physical phenomena observed in our laboratory and the LB software predictions.

关键词：计算流体力学；流量特性；地面试验

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An isolated power system consisting of battery energy storage system and fuel cell is able to maintain stable operation with constraints. One is the battery energy storage system must keep a state of charge within a certain range, and the other is the fuel cell must keep a limited rate for power change. We propose a coordinated operation method for the isolated power system taking into account both constraints.

关键词：燃料电池；电池储能系统；电力系统

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A mathematical model of a Molten Carbonate Fuel Cell (MCFC) is shown.The model is used to simulate an experimental lab-stand single fuel cell unit measuring 55 cm2.The comparison of simulated data against the experimental results is shown and commented on.

关键词：数学模型；熔融碳酸盐燃料电池；实验室支架

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We have pursued a number of research activities between April 2010 and April 2011: A detailed study on n-type doping in Cu2O by Br; An analysis of natural resource limitations to terawatt-scale solar cells; Attempt to achieve a 1.4-eV direct band gap in Ni sulfides (NiSx); First-principles studies of doping in Cu2O and electronic structures of NiSx. The following is a more detailed description of these activities.

关键词：太阳能电池；掺杂材料；原子结构；铜氧化物

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