Evaluate Si layers based on heteroepitaxial Si growth on RABITS textured metal substrates coated with textured buffer layers..

关键词：硅太阳能电池区；异质外延；图层；金属

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Photonic structures can exhibit significant absorption enhancement when an object s length scale is comparable to or smaller than the wavelength of light. This property has enabled photonic structures to be an integral component in many applications such as solar cells, light emitting diodes, and photothermal therapy. To characterize this enhancement at the single particulate level, conventional methods have consisted of indirect or qualitative approaches which are often limited to certain sample types. To overcome these limitations, we used a bilayer cantilever to directly and quantitatively measure the spectral absorption efficiency of a single silicon microwire in the visible wavelength range. We demonstrate an absorption enhancement on a per unit volume basis compared to a thin film, which shows good agreement with Mie theory calculations. This approach offers a quantitative approach for broadband absorption measurements on a wide range of photonic structures of different geometric and material compositions.

关键词：吸收光谱；光热性质；定量分析；宽带

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While examining fuel-reforming technology for fuel cells onboard aircraft, Glenn Research Center partnered with Garrettsville, Ohio-based Catacel Corporation through the Glenn Alliance Technology Exchange program and a Space Act Agreement. Catacel developed a stackable structural reactor that is now employed for commercial hydrogen production and results in energy savings of about 20 percent.

关键词：燃料电池；能量流失；能源节省

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This document describes the statement of work for National Renewable Energy Laboratory (NREL) as a subcontractor for Applied Nanotech, Inc. (ANI) for the Phase II SBIR contract with the Department of Energy to build silicon solar cells using non-contact printed, nanoparticle-based metallic inks. The conductive inks are based upon ANIs proprietary method for nanoparticle dispersion. The primary inks under development are aluminum for silicon solar cell back plane contacts and copper for top interdigitated contacts. The current direction of silicon solar cell technology is to use thinner silicon wafers. The reduction in wafer thickness reduces overall material usage and can increase efficiency. These thin silicon wafers are often very brittle and normal methods used for conductive feed line application, such as screen-printing, are detrimental. The Phase II program will be focused on materials development for metallic inks that can be applied to a silicon solar cell using non-contact methods. Uniform BSF (Back Surface Field) formation will be obtained by optimizing ink formulation and curing conditions to improve cell efficiency.

关键词：太阳能电池；铝；铜；效率；金属

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Methanol continues to be the most likely practical fuel for fuel cells operating at low internal temperatures. Enhanced knowledge of the electrochemistry of the anodic oxidation of methanol at platinum electrodes could assist in the attempts to improve the platinum-based electrocatalysts that are commonly employed in that technology. Numerous studies of the overall kinetics of the methanol anode have included identifying dissolved products and adsorbed species but little has been reported on the quantitative rate of the adsorption process. In the lower range of potentials, where no oxidative products are released to the electrolyte, the adsorption is initiated by an electrochemical dehydrogenation and follows Elovich kinetics. Specifically, adsorbed anions affect both the rate of methanol adsorption and its oxidation to desorbed products.

关键词：吸附；电极；基甲醇；阴离子；阳极；燃料电池

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Heat transfer of phase change material (PCM) in an open cell micro- foam structure was numerically studied. A high constant temperature was specified at the top surface of the structure. Each unit of the micro-foam is a body-centered-cubic (BCC) lattice embedded with spherical micro-pores. Two different simulation methodologies were applied. One is the high-fidelity direct numerical simulation (DNS), which allows for the effective thermo- physical parameters to be derived. The other methodology is a volume-averaged simulation based on one- and two-temperature models. Our results show that the volume-averaged simulation can accurately and efficiently capture the phase change process in PCM/micro-foam systems, with the effective thermal conductivity derived from direct simulations and expressed as a power law of porosity.

关键词：储电池；储能材料；热转化

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This presentation summarizes the results of NREL's analysis of hydrogen fuel cell performance in the key early markets of material handling equipment (MHE) and backup power.

关键词：备用电源；储能；燃料电池；氢能

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This report documents the demonstration of a self-adhering, thin-film photovoltaic (PV) technology applied to a new aluminum-zinc coated standing-seam metal roof (SSMR) with a high-performance coating. The demonstration took place at Kilauea Military Camp (KMC), HI, which has a uniquely corrosive environment due to the periodic presence of volcanic gases. It also has high electric utility costs and limited grid capacity. The corrosion performance of the roof and PV solar array was evaluated by periodic visual examination, onsite atmospheric coupon testing, and accelerated weathering laboratory tests of material coupons. Sensors were also installed at the interface between the PV membrane and roofing material, mounted in outdoor exposure at the site, to record any developing signs of corrosion. Af-ter a year in service, the PV appliqu modules were found to have no deleterious effect on the new SSMR, and the PV system performed as expected. However, due to the high first-costs related to procuring the thin-film PV components, the 30 year return on investment (ROI) ratio was only 0.19. Although the system is not economical enough to warrant Army-wide implementation, it may be specified in individual cases where energy sustainability is a higher priority than ROI.

关键词：光伏发电系统；太阳能；能量转换

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Under direct impact from ballistic loads, acoustic waves typically propagate throughout a structural component causing damage to sensitive areas. For structures with intelligent embedded monitoring systems, such as mounted piezoelectric actuators, a direct impact between 150 200 m/s of small-caliber rounds has produced catastrophic results. This report focuses on redirecting acoustic waves using non-traditional structural configurations. The technical approach utilizes periodic and graded metamaterials (produced from auxetic cellular, lattice topology and material composition), which are lightweight and can be assembled for extreme anisotropy and phononic bandgaps, which can be exploited to alter the propagation path of high amplitude stress waves. This research focuses on the initial stage of understanding how to tailor periodic lattices for highly concentrated impact and blast loads, which generally produce a broadband frequency response and yield only partial bandgaps. Specific attention is given to square, hexagonal, re-entrant, and modified re- entrant topologies. As a baseline comparison, a solid aluminum plate is examined against uniform and graded re-entrant unit cell lattices. The plates are individually subjected to both in- and out-of-plane direct impact loading conditions of a 0.22-caliber fragment simulating projectile traveling at 300 m/s. A less than 10% marginal difference in peak stress amplitude exists between the loading conditions for a given single through-the-thickness unit cell.

关键词：声波；弹道；结构组件；执行器；爆炸荷载

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Seven major instruments were purchased: (1) A DXR Smart Raman spectrometer, (2) A Bruker Tensor 27 FT Infrared Spectrometer, (3) An Alpha-Step D-120 Profilometer from KLA Tencor Corp., (4) A Rame-Hart model 250 Goniometer/Tensiometer, (5) an Agilent Diffuse Reflectance Accessory, (6) a Jelight Co. UVO cleaner, and (7) a Laurell Technologies Spin Coater. These instruments were used to characterize a variety of photoswitchable Donor-Acceptor (DA) dyads that were designed, synthesized, and evaluated as Interfacial Layers (ILs) in Organic Photovoltaic (OPV) devices and in Dye-Sensitized Solar Cells (DSSCs). Proof of the original proposal concept, photoswitched ILs, was unambiguously established.

关键词：有机光伏电池；数字转换；太阳能电池

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