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At least 1,063 records · Page 59

Powder Metallurgy of Uranium Alloy Fuels for TRU-Burning Reactors Final Technical Report

Overview Fast reactors were evaluated to enable the transmutation of transuranic isotopes generated by nuclear energy systems. The motivation for this was that TRU isotopes have high radiotoxicity and relatively long half-lives, making them unattractive for disposal in a long-term geologic repository. Fast reactors provide an efficient means to utilize the energy content of the TRUs while destroying them. An enabling technology that requires research and development is the fabrication metallic fuel containing TRU isotopes using powder metallurgy methods. This project focused upon developing a powder metallurgical fabrication method to produce U-Zr-transuranic (TRU) alloys at relatively low processing temperatures (500ºC to 600ºC) using either hot extrusion or alpha-phase sintering for charecterization. Researchers quantified the fundamental aspects of both processing methods using surrogate metals to simulate the TRU elements. The process produced novel solutions to some of the issues relating to metallic fuels, such as fuel-cladding chemical interactions, fuel swelling, volatility losses during casting, and casting mold material losses. Workscope There were two primary tasks associated with this project: 1. Hot working fabrication using mechanical alloying and extrusion • Design, fabricate, and assemble extrusion equipment • Extrusion database on DU metal • Extrusion database on U-10Zr alloys • Extrusion database on U-20xx-10Zr alloys • Evaluation and testing of tube sheath metals 2. Low-temperature sintering of U alloys • Design, fabricate, and assemble equipment • Sintering database on DU metal • Sintering database on U-10Zr alloys • Liquid assisted phase sintering on U-20xx-10Zr alloys Appendices Outline Appendix A contains a Fuel Cycle Research & Development (FCR&D) poster and contact presentation where TAMU made primary contributions. Appendix B contains MSNE theses and final defense presentations by David Garnetti and Grant Helmreich outlining the beginning of the materials processing setup. Also included within this section is a thesis proposal by Jeff Hausaman. Appendix C contains the public papers and presentations introduced at the 2010 American Nuclear Society Winter Meeting. Appendix A—MSNE theses of David Garnetti and Grant Helmreich and proposal by Jeff Hausaman A.1 December 2009 Thesis by David Garnetti entitled “Uranium Powder Production Via Hydride Formation and Alpha Phase Sintering of Uranium and Uranium-Zirconium Alloys for Advanced Nuclear Fuel Applications” A.2 September 2009 Presentation by David Garnetti (same title as document in Appendix B.1) A.3 December 2010 Thesis by Grant Helmreich entitled “Characterization of Alpha-Phase Sintering of Uranium and Uranium-Zirconium Alloys for Advanced Nuclear Fuel Applications” A.4 October 2010 Presentation by Grant Helmreich (same title as document in Appendix B.3) A.5 Thesis Proposal by Jeffrey Hausaman entitled “Hot Extrusion of Alpha Phase Uranium-Zirconium Alloys for TRU Burning Fast Reactors” Appendix B—External presentations introduced at the 2010 ANS Winter Meeting B.1 J.S. Hausaman, D.J. Garnetti, and S.M. McDeavitt, “Powder Metallurgy of Alpha Phase Uranium Alloys for TRU Burning Fast Reactors,” Proceedings of 2010 ANS Winter Meeting, Las Vegas, Nevada, USA, November 7-10, 2010 B.2 PowerPoint Presentation Slides from C.1 B.3 G.W. Helmreich, W.J. Sames, D.J. Garnetti, and S.M. McDeavitt, “Uranium Powder Production Using a Hydride-Dehydride Process,” Proceedings of 2010 ANS Winter Meeting, Las Vegas, Nevada, USA, November 7-10, 2010 B.4. PowerPoint Presentation Slides from C.3 B.5 Poster Presentation from C.3 Appendix C—Fuel cycle research and development undergraduate materials and poster presentation C.1 Poster entitled “Characterization of Alpha-Phase Sintering of Uranium and Uranium-Zirconium Alloys” presented at the Fuel Cycle Technologies Program Annual Meeting C.2 April 2011 Honors Undergraduate Thesis by William Sames, Research Fellow, entitled “Uranium Metal Powder Production, Particle Distribution Analysis, and Reaction Rate Studies of a Hydride-Dehydride Process"

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Solid Lighting Core Technologies

The overall objective of this project is to demonstrate an ultra-effective light extraction mechanism that can be universally applied to all top-emitting white OLEDs (TE-WOLEDs) and can be integrated with thin film encapsulation techniques. The scope of work proposed in this project includes four major areas: (1) optical modeling; (2) microlens and array fabrication; (3) fabrication, encapsulation, and characterization of TE-WOLEDs; and (4) full device integration and characterization. First , the light extraction efficiency in a top-emitting OLED with or without a microlens array are modeled using wave optics. Second , individual microlenses and microlens arrays are fabricated by inkjet printing of microdroplets of a liquid thiol-ene monomer with high refractive index followed by photopolymerization. Third , high efficiency top-emitting white OLEDs are fabricated, and fully characterized. Finally , optimized microlens arrays are fabricated on TE-WOLEDs with dielectric barrier layers. The overall light extraction efficiency of these devices, as well as its wavelength and angular dependencies, are measured by comparing the efficiencies of devices with and without microlens arrays. In conclusion, we have demonstrated the feasibility of applying inkjet printed microlens arrays to enhance the light extraction efficiency of top-emitting white OLEDs. We have shown that the geometry (contact angle) of the printed microlenses can be controlled by controlling the surface chemistry prior to printing the lenses. A 90% enhancement in the light extraction efficiency has been achieved with printed microlens array on a top-emitting white OLED, which can be further improved to 140% using a more close-packed microlens array fabricated from a molding process. Future work will focus on improvement of the microlens fabrication process to improve the array fill factor and the contact angle, as well as use transparent materials with a higher index of refraction. We will also further optimize the procedures for integrating the microlenses on the top-emitting white OLEDs and characterize the overall light extraction enhancement factor when the microlens array is attached.

36 MATERIALS SCIENCE↗

Machining Elimination through Application of Thread Forming Fasteners in Net-Shaped Cast Holes

The ultimate objective of this work was to eliminate approximately 30% of the machining performed in typical automotive engine and transmission plants by using thread forming fasteners in as-cast holes of aluminum and magnesium cast components. The primary issues at the source of engineers reluctance to implementing thread forming fasteners in lightweight castings are: • Little proof of consistency of clamp load vs. input torque in either aluminum or magnesium castings. • No known data to understand the effect on consistency of clamp load as casting dies wear. The clamp load consistency concern is founded in the fact that a portion of the input torque used to create clamp load is also used to create threads. The torque used for thread forming may not be consistent due to variations in casting material, hole size and shape due to tooling wear and process variation (thermal and mechanical). There is little data available to understand the magnitude of this concern or to form the basis of potential solutions if the range of clamp load variation is very high (> +/- 30%). The range of variation that can be expected in as-cast hole size and shape over the full life cycle of a high pressure die casting die was established in previous work completed by Pacific Northwest National Laboratory, (PNNL). This established range of variation was captured in a set of 12 cast bosses by designing core pins at the size and draft angles identified in the sited previous work. The cast bosses were cut into nuts that could be used in the Ford Fastener Laboratory test-cell to measure clamp load when a thread forming fastener was driven into a cast nut. There were two sets of experiments run. First, a series of cast aluminum nuts were made reflecting the range of shape and size variations to be expected over the life cycle of a die casting die. Taptite thread forming fasteners, (a widely used thread forming fastener suitable for aluminum applications), were driven into the various cored, as-cast nuts at a constant input torque and resulting clamp loads were recorded continuously. The clamp load data was used to determine the range of clamp loads to be expected. The bolts were driven to failure. The clamp load corresponding to the target input of 18.5 Nm was recorded for each fastener. In a like fashion, a second set of experiments were run with cast magnesium nuts and ALtracs thread forming fasteners, (a widely used thread forming fastener suitable for magnesium applications). Again all clamp loads were recorded and analyzed similarly to the Taptites in aluminum cast nuts. Results from previous work performed on the same test cell for a Battelle project using standard M8 bolts into standard M8 nuts were included as a comparator for a standard bolt and nut application. The results for the thread forming fasteners in aluminum cast holes were well within industry expectations of +/- 30% for out of the box and robustness range testing. The results for the dry and lubed extreme conditions were only slightly higher than industry expectations at +/- 35.6%. However, when compared to the actual Battelle results (+/- 40%) for a standard bolt and nut the tread forming fasteners performed slightly better. The results for the thread forming fasteners in magnesium cast holes were all well within industry expectations of +/- 30% for all three conditions. The robustness range (.05mm larger and smaller holes than the expected wear pattern of a die casting die at full life cycle) results also fell within the industry expectations for standard threaded fasteners. These results were very encouraging. It was concluded that this work showed that clamp load variation with thread forming fasteners is consistent with industry expectations for standard steel bolts and nuts at +/- 30%. There does not appear to be any significant increase in clamp load variation due to the application of thread forming fasteners in as-cast holes of aluminum or magnesium over the effective life of a die casting mold. The fully implemented potential benefit of thread forming fasteners in as-cast holes of aluminum and magnesium is estimated to be 6 trillion Btu per year for North America. Economic benefit is estimated to be nearly $800 million per year. Environmental benefits and quality improvements will also result from full implementation of this technology.

36 MATERIALS SCIENCE↗

Technical Assistance from NREL to Wind Tower Technologies

This effort will use NREL capabilities in techno-economic analysis to evaluate a technology developed by Wind Tower Technologies (WTT) for an onsite process for building concrete towers using a precast mated mold process. This technology enables tall towers by circumventing transportation limits that constrain the size of conventional steel monopole towers. NREL researchers will provide relevant expertise in techno-economic analysis and assessment of innovative technologies for wind energy applications.

17 WIND ENERGY↗

6.26 Low Cost Basalt Fiber for Automotive Applications

Vehicle lightweighting is an essential component to the automotive industry to improve fuel economy of internal combustion engine (ICE) vehicles to meet ever improving emission standards and to improve the range of electric vehicles (EV). Composite materials offer high specific modulus and specific strength, which makes them appealing for these light weighting efforts. Sheet molding compounds (SMC) are particularly interesting from an automotive perspective because of the relatively low cost and high volume of producing SMC parts. Traditionally, composite materials for automotive application are glass fiber reinforced because of the attractive price - performance ratio, but basalt fibers are a cost and recycling competitive reinforcement alternative in this market. The aim of this project was to examine the feasibility of utilizing basalt fiber for automotive applications. More specifically, an effort was made to examine different fiber sizings on basalt fiber combined with vinyl-ester (VE) resin, and their performance as part of an SMC process. In addition to offering vehicle lightweighting with fiber reinforced polymer composites, basalt fiber is a fully recyclable material and thus supports the IACMI technical goal of: Demonstrate that the technology is capable at a sufficient scale for >80% recyclability or reuse of fiber reinforced polymer composites in five years into useful components with projected cost and quality at commercial scale competitive with virgin materials on a pathway to 95% recyclability or reuse starting in ten years. Three different fiber sizings were applied to a continuous roving of basalt fiber and compared to a traditional Electrical/Chemical Resistance (E-CR) glass fiber that is typically used in these types of applications. Fiber tows were examined for Loss on Ignition percentage (LOI%), Tex, and tow strength. Some sizings clearly outperformed others, and the ability to process these fibers on a pilot scale SMC line was demonstrated. A test plan for the manufacturing and mechanical testing of SMC panels was developed. This work continues outside the time frame allocated for this project. When this work is completed, it will be added to this report and posted as Appendix C. Glass fiber reinforced SMC materials have already proven feasible as a light weighting method for traditionally steel parts like the Volkswagen (VW) Atlas lift-gate (Figure 1); this project team is seeking the feasibility of basalt fiber as a drop-in replacement for glass fiber reinforced SMC. Sizing development for basalt fibers has proven that the mechanical properties are better than E-glass and closer to S-glass, which makes it an interesting material for SMC applications. Better mechanical properties translate to less material needed to achieve load case requirement for target applications. The business case has already been demonstrated for 100,000 parts per year of glass fiber reinforced SMC Atlas lift-gates compared to traditional steel manufacturing processes. Reduced overhead and assembly costs are offset by glass fiber SMC higher cost per kg beyond 100,000 parts per year, which is still a relatively low volume for the automotive industry. For basalt fiber reinforced SMC to become feasible for automotive applications, the price-performance ratio has to be precisely determined. Based on the mechanical performance it is possible to establish a range of applications and technical solutions in which the potential of basalt SMC can be utilized, while the price of the material can be used to compile the business case for such applications. Based on these business cases and the sustainability indicators, glass fiber reinforcement (or other) materials can be directly substituted. Volkswagen’s commitment to reducing carbon emissions cannot be understated. Basalt fiber shows promise of reducing the carbon footprint in SMC materials, especially if sizing optimizations can be made with thermoplastic based SMC. To fully realize the value of basalt fiber reinforced materials, a lifecycle cost analysis should be performed on basalt’s production and recycling, and then compared against E-glass. From this assessment, a true judgement can be made on the commercialization potential of this material. Figure 1. Example of Fiber Reinforced Polymer Composite Liftgate As a conclusion, we can state that Mafic basalt fiber is not a direct replacement for E-glass or E-CR glass based on price, but should be considered a technical solution when E-glass does not provide adequate performance in a composite design and S-glass, aramid and carbon fibers are too costly. Mafic basalt fiber can be placed on the high-performance fiber spectrum next to S-glass for performance but at one third the price. It should be considered for more technically challenging structural designs wherein the performance can demonstrate 20-25% performance enhancement over E-glass to elicit more strength or a weight reduction. Both Michelman and Mafic produce thermoplastic sizings which, in combination with Nylon and polypropylene resin and fibers, can further advance high speed composite implementations while maintaining an eco-friendly manufacturing process.

36 MATERIALS SCIENCE↗

A Succinct Study of Silastic J

Silastic TM RTV-4130-J Base and Curing agent, also known as Silastic J, is a two-part addition cure silicone commonly used for molding due to its dimensional stability. The material has a wide variety of applications that the paper will address.

36 MATERIALS SCIENCE↗

Reducing Deferrals by Integrating Health Homes with Weatherization

The U.S. Department of Energy’s Weatherization Assistance Program (WAP) improves energy efficiency and household health for low-income families, yet a substantial number of otherwise eligible homes are deferred from due to health and safety concerns in their homes, including mold, moisture damage, or structural deficiencies. These deferred homes are often occupied by marginalized or otherwise vulnerable residents who may be exposed to elevated indoor air pollutant concentration. Integrating Healthy Homes (HH) interventions with weatherization has been proposed as a strategy to reduce deferrals, address environmental justice concerns, and improve health outcomes. However, limited data on the health and economic implications of such integration exist. This study aimed to assess the potential health benefits and savings-to-investment ratio (SIR) associated with integrating Healthy Homes interventions into weatherization programs for homes typically deferred from WAP services. We collected indoor air pollutant data from homes undergoing health home renovations, including fine particulate matter (PM 2.5 ), nitrogen dioxide (NO 2 ), carbon monoxide (CO), and formaldehyde, with sampling times up to one month. Except for fomaldehyde, which was measured using passive UMEx badges, the other metrics were measured using the airQ Pro indoor air quality monitor.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Improving the performance of high-strength steel castings by specialized cooling

The influence of microcooling and external cooling on the structure and mechanical properties of moderately alloyed high-strength special-purpose steel and also on the morphology of its nonmetallic inclusions is investigated. The properties of castings obtained in different molds and in different conditions are compared. The influence of hybrid (external and internal) modification of the casting process on the quality of heavy housing castings is investigated.

42 ENGINEERING↗

Glass-filled polyurethane in manufacturing

The physicomechanical and operational properties of glass-filled polyurethane obtained by long fiber injection molding (LFI) and fiber composite spraying (FCS) are investigated. It is clear that glass-filled polyurethane may be used in producing components with different surface texture (dashboard, door trim, armrests) in the auto industry.

42 ENGINEERING↗

Mechanical Response and Processability of Wet-Laid Recycled Carbon Fiber PE, PA66 and PET Thermoplastic Composites

The interest in recycled carbon fiber (rCF) is growing rapidly and the supply chain for these materials is gradually being established. However, the processing routes, material intermediates and properties of rCF composites are less understood for designers to adopt them into practice. This paper provides a practical pathway for rCFs in conjunction with low cost and, for the most part, commodity thermoplastic resins, namely polyethylene (PE), polyamide 66 (PA66) and polyethylene terephthalate (PET). Industrially relevant wet-laid (WL) process routes have been adopted to produce mats using two variants of WL mats, namely (a) high speed wet-laid inclined wire to produce broad good ‘roll’ forms and (b) 3DEPTM process patented by Materials Innovation Technologies (MIT)-recycled carbon fiber (RCF), now Carbon Conversions, which involves mixing fibers and water and depositing the fibers on a water-immersed mold. These are referred to as ‘sheet’ forms. The produced mats were evaluated for their processing into composites as ‘fully consolidated mats’ and ‘non-consolidated’ as-produced mats. Comprehensive mechanical data in terms of tensile strength, tensile modulus and impact toughness for rCF C/PE, C/PA66 and C/PET are presented. The work is of high value to sustainable composite designers and modelers.

compression molding↗

Retrospective Analysis of NIST Standard Reference Material 1450, Fibrous Glass Board, for Thermal Insulation Measurements

Thermal conductivity data acquired previously for the establishment of Standard Reference Material (SRM) 1450, Fibrous Glass Board, as well as subsequent renewals 1450a, 1450b, 1450c, and 1450d, are re-analyzed collectively and as individual data sets. Additional data sets for proto-1450 material lots are also included in the analysis. The data cover 36 years of activity by the National Institute of Standards and Technology (NIST) in developing and providing thermal insulation SRMs, specifically high-density molded fibrous-glass board, to the public. Collectively, the data sets cover two nominal thicknesses of 13 mm and 25 mm, bulk densities from 60 kg∙m -3 to 180 kg∙m -3 , and mean temperatures from 100 K to 340 K. The analysis repetitively fits six models to the individual data sets. The most general form of the nested set of multilinear models used is given in the following equation: λ(ρ, T) = α 0 + α 1 ρ +α 2 T + α 3 T 3 +α 4 e - ($\frac{T-a_{5}}{a_{6}}$) 2 = where λ(ρ,T) is the predicted thermal conductivity (W∙m -1 ∙K -1 ), ρ is the bulk density (kg∙m -3 ), T is the mean temperature (K) and $a_i$ (for i = 1, 2, … 6) are the regression coefficients. The least squares fit results for each model across all data sets are analyzed using both graphical and analytic techniques. The prevailing generic model for the majority of data sets is the bilinear model in ρ and T. λ(ρ, T) = α 0 + α 1 ρ +α 2 T One data set supports the inclusion of a cubic temperature term and two data sets with low-temperature data support the inclusion of an exponential term in T to improve the model predictions. Physical interpretations of the model function terms are described. Recommendations for future renewals of SRM 1450 are provided. An Addendum provides historical background on the origin of this SRM and the influence of the SRM on external measurement programs.

regression analysis↗

Release of the NASA Parallel Electric-Gas Architecture with Synergistic Utilization Scheme (PEGASUS) OpenVSP Model

The Open VSP model represents the geometry of PEGASUS as is currently modeled. PEGASUS is a concept vehicle that will not be physically produced. As such, the baseline model is subject to change without notice or requirement that updates are provided external to NASA. The current baseline is derived from the outer mold line (OML) of the ATR 42-500. As such, planform areas for the wing, fuselage, vertical tail, and horizontal tail mimic those published in public ATR 42 literature. NASA Aeronautics Systems Analysis Branch (ASAB) does not contain any proprietary data on the ATR 42, thus the PEGASUS model does not contain any proprietary or sensitive information. Further, model details that are required for an actual aircraft such as airfoils, twist distributions and propeller geometries are unknown at this time, and generic stand-ins are used within the OpenVSP model. The intent is to provide this model to Georgia Tech ASDL to allow the ASDL team to model the impact of the propulsion system at the wingtip’s impact on structural characteristics. The ASDL will be using the model to generate estimated aerodynamic load and structural members for analysis.

PEGASUS↗

Process Development for Stamping Á-Pillar Covers with Aluminum

In this work, performed in close collaboration with PACCAR and Magna International, a 6XXX series aluminum alloy was used for the development of A-Pillar cover for the cab of a typical heavy-duty Class-8 truck. The use of Al alloy for the A-pillar cover represents an approximately 40% weight savings over its steel or molded fiberglass composite counterpart. For the selected Al alloy, a small amount of cold work (5% tensile strain), following prior hot-forming, was found to significantly improve the subsequent age-hardening response. The role of solutionizing temperature and rate of cooling on the age-hardening response after paint-bake treatment were investigated. For the temperature range selected in this work, higher solutionizing temperature correlated with greater subsequent age-hardening and vice-versa. However, the age-hardening response was insensitive to the mode of cooling (water quench vs. air cooling). Finally, a two-step forming process was developed where, in the first step, the blank was heated to solutionizing temperature, quenched, and then partially formed at room temperature. For the second step, the pre-form was re-heated and quenched as in the first step, and the forming was completed at room temperature. The resulting A-pillars had sufficient residual ductility to be compatible with hemming and riveting

A-pillar cover↗

Infusible Thermoplastic Composites for Wind Turbine Blade Manufacturing: Fatigue Life of Thermoplastic Laminates under Ambient and Low-Temperature Conditions

Traditionally, thermoset resins such as polyesters (PE) and epoxies are used as the polymer matrix for construction of wind turbine blades. However, concern about their end-of-life treatment garners interest to use thermoplastics for increased recyclability. However, the high viscosity of molten thermoplastics inhibits their use in manufacturing wind turbine blades with injection or compression molding. A recently developed, infusible, reactive thermoplastic resin overcomes this technological barrier. Toward verifying that this recyclable resin is suitable for use in wind turbine blades, a dataset of R?=?0.1 and R?=?10 fatigue data for glass fiber-reinforced acrylic composites is provided and equal fatigue life to industry standard epoxy and unsaturated PE resin systems is demonstrated. Specifically, R?=?0.1 fatigue data for acrylic composites at room temperature and -30?degrees C for verification of low-temperature performance are tabulated. To elucidate failure mechanisms, in situ mechanical testing with X-ray computed tomography demonstrates that damage accumulation occurs by crack propagation along the fiber-matrix interface under cyclic loading. Infrared (IR) thermography predicts failure points in composites specimens with porosity defects introduced from nonideal manufacturing processes. Furthermore, these manufacturing defects are shown to compromise the fatigue life of the acrylic laminates by an order of magnitude.

effect of defects↗

Deformable, Programmable, and Shape-Memorizing Micro-Optics

The use of shape memory polymers is demonstrated for deformable, programmable, and shape-memorizing micro-optical devices. A semi-crystalline shape memory elastomer, crosslinked poly(ethylene-co-vinyl acetate), is used to prepare various micro-optic components, ranging from microlens and microprism arrays to diffraction gratings and holograms. Here, the precise replication of surface features at the micro- and nanoscale and the formation of crosslinked shape memory polymer networks can be achieved in a single step via compression molding. Further deformation via hot pressing or stretching of micro-optics formed in this manner allows manipulation of the microscopic surface features, and thus the corresponding optical properties. Due to the shape memory effect, the original surface structures and the optical properties can be recovered and the devices be reprogrammed, with excellent reversibility in the optical properties. Furthermore, arrays of transparent resistive microheaters can be integrated with deformed micro-optical devices to selectively trigger the recovery of surface features in a spatially programmable manner, thereby providing additional capabilities in user-definable optics.

36 MATERIALS SCIENCE↗

A new class of renewable thermoplastics with extraordinary performance from nanostructured lignin-elastomers

In this study, a new class of thermoplastic elastomers has been created by introducing nanoscale-dispersed lignin (a biomass-derived phenolic oligomer) into nitrile rubber. Temperature-induced controlled miscibility between the lignin and the rubber during high shear melt-phase synthesis allows tuning the material s morphology and performance. The sustainable product has unprecedented yield stress (15–45 MPa), strain hardens at large deformation, and has outstanding recyclability. The multiphase polymers developed from an equal-mass mixture of a melt-stable lignin fraction and nitrile rubber with optimal acrylonitrile content, using the method described here, show 5–100 nm lignin lamellae with a high-modulus rubbery interphase. Molded or printed elastomeric products prepared from the lignin-nitrile material offer an additional revenue stream to pulping mills and biorefineries. Research was sponsored by the Technology Innovation Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Department of Energy. TEM (J.C. and C.D.T.) and SAXS (J.K.K.) experiments were conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.

36 MATERIALS SCIENCE↗