With the intent of increasing the efficiency of laser-gas interactions, an external bidirectional multipass optical cavity has been developed for use with counterpropagating high energy pulsed lasers. By exploiting the closed-path recirculation of two counterpropagating laser pulses, obtained through polarization-dependent trapping of the pulses inside the cavity via a Pockels cell, such an optical cavity allows the counterpropagating pulses to repeatedly and concurrently interact within a specific region in space. This cavity allows the setup to exhibit an effective pulse repetition frequency much higher than the loading laser. This increased repetition frequency permits greater sensitivity in probing a medium or increased energy deposition, depending on application, over the single pass case. Pulses from a 12 mJ, frequency doubled, 5 ns FWHM, pulsed Nd:YAG laser were split and injected into opposing sides of a symmetric multipass 2.44 m (96 in) optical ring cavity. Using a Pockels cell, the counterpropagating pulses were 'locked' into the cavity for cavity round trips. This represents an 8 fold increase in the interacting laser energy over the single pass case. This cavity concept suggests a variety of potential applications ranging from established cavity processes, e.g. laser-based absorption spectroscopy studies and x-ray production, to new processes which can benefit from the counterpropagating feature of this design, such as non-resonant optical lattice gas heating and time-resolved coherent Rayleigh-Brillouin scattering diagnostic studies of a rapidly evolving flow.

关键词：实验设计；高能量激光；激光腔

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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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Ennoblement, a positive shift in corrosion potential, due to biofilm formation is the basis of patents for biofilm monitoring and power generating devices. Ennoblement is a global phenomenon that is routinely cited as a mechanism for microbiologically influenced corrosion of some passive alloys. Increased corrosion is attributed to acceleration of the oxygen reduction reaction via several potential mechanisms that have been debated for decades. Because the phenomenon is predictable and reproducible at specific locations, ennoblement is the basis for patented methods and devices for monitoring biofilm formation and relating ennobled potentials to increased likelihood of corrosion and for evaluating cleaning and biocide treatments. Furthermore, when anodes and cathodes can be separated, as in a microbial fuel cell, biofilm formation on the cathode increases the potential difference between the two and the resulting power output. Most patented fuel cells using metal cathodes do not refer specifically to ennoblement in the disclosures.

关键词：腐蚀；能源；指标；阴极；燃料电池

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Microbial fuel cells, in which living microorganisms convert chemical energy into electricity, represent a potentially sustainable energy technology for the future. Here we report the single-bacterium level current measurements of Geobacter sulfurreducens DL-1 to elucidate the fundamental limits and factors determining maximum power output from a microbial fuel cell. Quantized stepwise current outputs of 92(+ or -33) and 196(+ or -20) fA are generated from microelectrode arrays confined in isolated wells. Simultaneous cell imaging/tracking and current recording reveals that the current steps are directly correlated with the contact of one or two cells with the electrodes. This work establishes the amount of current generated by an individual Geobacter cell in the absence of a biofilm and highlights the potential upper limit of microbial fuel cell performance for Geobacter in thin biofilms.

关键词：细菌；;电流；电化学；电极

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The United States Department of Energy (DOE) Fissile Materials Disposition Program (FMDP) is pursuing disposal of surplus weapons-usable plutonium by reactor irradiation as the fissile constituent of MOX fuel. Lead test assemblies (LTAs) have been irradiated for approximately 36 months in Duke Energy's Catawba-1 nuclear power plant (NPP). Per the mixed oxide (MOX) fuel topical report, approved by the U.S. Nuclear Regulatory Commission (NRC), destructive post-irradiation examinations (PIEs) are to be performed on second cycle rods (irradiated to an average burnup of approximately 45 GWd/MTHM). The Radiochemical Analysis Group (RAG) at Oak Ridge National Laboratory (ORNL) is currently performing the detailed destructive post-irradiation examinations (PIE) on four of the mixed uranium and plutonium oxide fuel rods. The analytical process involves dissolution of designated fuel segments in a shielded hot cell for high precision quantification of select fission products and actinide isotopes employing isotope dilution mass spectrometry (IDMS) among other analyses. The hot cell dissolution protocol to include the collection and subsequent alkaline fusion digestion of the fuels acid resistant metallic particulates will be presented. Although the IDMS measurements of the fission products and actinide isotopes will not be completed by the time of the 51st INMM meeting, the setup and testing of the HPLC chromatographic separations in preparation for these measurements will be discussed.

关键词：混合氧化物燃料；钚氧化物；铀；锕系元素原子核

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GaAs Laser Power Converters (LPC) were simulated in 2D and 3D under 10 W/cm2 illumination of 810 nm light using Synopsys Sentaurus software revealing significant dependence of effciency on grid metal finger spacings, S, and finger dimensions. Efficiency results were comparable to an experimental efficiency of 53.4% cited in the literature for an LPC under 43 W/cm2 of 810 nm laser light. 2D devices were simulated with S of 20 - 1000 micrometer revealing an efficiency drop, Delta(n), with increasing spacings. The efficiency drop was reduced from Delta(n) of 39.43% at S = 740 micrometer to Delta(n) of 14.38% at S = 1000 micrometer when modifying the window layer to include a highly doped lateral conduction layer (LCL). In the 3D simulations, resistive losses in the grid metal fingers were reduced by thickening the grid metal from 3 micrometer x 0.5 micrometer with an efficiency of 26% at an effective length of 0.5 cm up to 10 micrometer x 5 micrometer, achieving an efficiency of 44.89% at an effective finger length of 1 cm. An LCL and thicker fingers are shown to be critical for designing large area LPCs to convert laser light to electrical power for devices such as small RPAs and tactical sensors.

关键词：光伏反应；太阳能电池；电阻损失

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Abundant for most of the year in most parts of the world, solar energy is the ultimate renewable zero-emission energy source. Combined with improved means of energy storage, it has the potential to supply a quickly increasing fraction of our energy needs. However, its widespread use for electricity generation requires a significant further decrease in cost, which will be difficult to meet with conventional crystalline silicon technology. Allowing for the use of inexpensive, high-speed, large-scale roll-to-roll manufacturing processes, organic photovoltaics (OPV) have a significant chance of quickly becoming an essential factor in electricity generation1, but additional improvements in performance and life-time are needed before large-scale implementation. OPV devices, also called polymer-solar cells (PSC) or polymer-fullerene composite solar cells, are lightweight and can be flexible, opening the possibility for a range of new applications including largearea pliable devices. While power-conversion efficiencies of up to 7.9% have been reported at a laboratory scale, practical maximum efficiencies between 20 and 25% appear to be reasonable. Nanoscale morphology has been identified as an important factor in the optimization of OPV. In addition to tuning the optical and electronic properties of the materials used for light harvesting, carrier generation, transport, and collection, control of the nanoscale morphology of the active layer can alone provide a clear path to power conversion efficiencies of >10%. Tandem devices can certainly dramatically improve overall efficiencies but taking into account their complexity, additional gains can and must be made in single-layer devices.

关键词：复合材料；电；储能；有机材料;；光伏电池

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Materials capable of responding to external stimuli including pH, temperature, magnetic and electric field, undergoing conformational changes are considered to be one of the most exciting and emerging classes of advanced materials receiving considerable scientific interest especially in the biomedical field. Stimuli-responsive polymers in the form of micro- or nanofibers have received great attention during the last 10 years and have been exploited in a diverse range of biomedical applications such as drug delivery, tissue engineering, bioseparation and biosensing. One of the most popular and versatile fiber fabrication methods used for the production of fibers is electrospinning. Its simplicity, cost-effectiveness and applicability not only to pristine synthetic and natural polymers but also to composites, enables the development of polymer-based fibrous nanocomposites via the combination of polymers with inorganic nanofillers. Among such nanoadditives, magnetic nanoparticles capable of interacting with an externally applied magnetic field, are particularly attractive owing to their potential biomedical applications including magnetically-triggered drug delivery, magnetic cell seeding, magnetic bioseparation, hypothermia cancer treatment and contrast enhancement in magnetic resonance imaging. In this chapter, an introductory section on electrospinning and on different parameters influencing this process is initially provided. The different fabrication routes for generating electrospun magnetoactive polymer-based (nano)fibrous materials are briefly discussed and finally the applicability of these materials in the biomedical field including tissue engineering, drug delivery, hypethermia treatment and biosensing is reviewed.

关键词：电池材料；磁极活性；纳米材料

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The presentation, 'NREL Fuel Cell and Hydrogen Technologies Program Overview,' was presented at the Fuel Cell and Hydrogen Energy Expo and Policy Forum, April 24, 2013, Washington, D.C.

关键词：燃料电池；氢能；能源系统

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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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