关键词：机械；催化；核电

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The aluminum nanoparticles (Al NPs) are demonstrated to serve as active photothermal media, to enhance and control local photothermal energy deposition via the photothermal effect activated by localized surface plasmon resonance (LSPR) and amplified by Al NPs oxidation. The activation source is a 2-AA-battery-powered xenon flash lamp. The extent of the photothermally activated movement of Al NPs can be approx. 6 mm. Ignition delay can be approx. 0.1 ms. Both scanning electron microscopy and energy-dispersive X-ray spectroscopy measurements of motion-only and after-ignition products confirm significant Al oxidation occurs through sintering and bursting after the flash exposure. Simulations suggest local heat generation is enhanced by LSPR. The positive- feedback effects from the local heat generation amplified by Al oxidation produce a large increase in local temperature and pressure, which enhances movement and accelerates ignition.

关键词：电池能源；光热光谱分析；等离子体

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A Forward Operating Base (FOB) is designed to support combat operations in an austere environment, which often lacks pre-existing infrastructure. On-site diesel generators are the primary source of FOB electricity. Traditionally, each generator is connected to its own set of loads and operates independently from other generators. The benefits of transitioning from traditional generator employment to an alternative architecture using an Energy Management System (EMS) were investigated in this thesis. The EMS provides an interface between power sources, loads, and energy storage elements to form a microgrid. Using power electronics and programmable logic, the EMS provides capabilities such as power source selection, power metering, flow control, and peak power management. These capabilities enable more efficient generator utilization by matching real-time load demand to the smallest capable power source, reducing overall fuel consumption. The EMS offers redundancy as it can connect any one of multiple power sources to critical loads. A hardware- based laboratory experiment demonstrated the ability to transition from one power source to another while providing uninterrupted current to the load. The results of the experiment validate a Simulink model of the EMS. An example load profile was applied to the model to compare overall fuel consumption between the traditional architecture and the EMS-enabled microgrid.

关键词：柴油燃料；发电机；能源管理

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A low voltage,low power up-conversion mixer is presented here for 2.4GHz wireless sensor networks (WSN).It was based on a double-balanced Gilbert cell type.The current-reuse technique was used to reduce the power consumption and negative-resistance compensation technique was used to improve the conversion gain.The mixer was designed in 0.18μm RF CMOS technology,and was simulated with Cadence SpectreRF.The simulation results indicate that the conversion gain is 6.37dB,the noise figure is 15.36dB and the input 1dB compression point is -10.3dBm,while consuming 1mA current for operating voltage at 1V.

关键词：混频器；电流再利用；低电压；低功耗

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In this report we explore claims that phase conjugation of high energy lasers by stimulated Brillouin scattering (SBS) can compensate optical aberrations associated with severely distorted laser amplifier media and aberrations induced by the atmosphere. The SBS media tested was a gas cell pressurized up to 300 psi with SF6 or Xe or both. The laser was a 10 Hz, 3J, Q-switched Nd:YAG with 25 ns wide pulses. Atmospheric aberrations were created with space heaters, helium jets and phase plates designed with a Kolmogorov turbulence spectrum characterized by a Fried parameter, ro, ranging from 0.6 6.0 mm. Phase conjugate tests in the laboratory were conducted without amplification. For the strongest aberrations, D/ro approx. 20, created by combining the space heaters with the phase plate, the Strehl ratio was degraded by a factor of approx. 50. Phase conjugation in SF6 restored the peak focusable intensity to about 30% of the original laser. Phase conjugate tests at the outdoor laser range were conducted with laser amplifiers providing gain in combination with the SBS cell. A large 600,000 BTU kerosene space heater was used to create turbulence along the beam path. An atmospheric structure factor of Cn2 = 5x10-13 m2/3 caused the illumination beam to expand to a diameter 250mm and overfill the receiver. The phase conjugate amplified return could successfully be targeted back onto glints 5mm in diameter. Use of a lenslet arrays to lower the peak focusable intensity in the SBS cell failed to produce a useful phase conjugate beam; The Strehl ratio was degraded with multiple random lobes instead of a single focus. I will review literature results which show how multiple beams can be coherently combined by SBS when a confocal reflecting geometry is used to focus the laser in the SBS cell.

关键词：激光；畸变；放大器；光散射

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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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In this report, we present results of an ongoing study aimed at measuring and optimizing the nonradiative lifetime and the internal radiative quantum efficiency of molecular beam epitaxy (MBE)-grown gallium arsenide (GaAs) solar cells that are grown at the U.S. Army Research Laboratory (ARL) using different substrate growth temperatures and arsenic (As)/gallium (Ga) flux ratios to determine the growth parameters that maximize the bulk GaAs minority carrier nonradiative lifetime. We report a significant increase in the nonradiative lifetime and the internal radiative quantum efficiency of MBE- grown GaAs/aluminum gallium arsenide (AlGaAs) double heterostructure (DH) structures grown at ARL with a growth temperature of 595 C and an As/Ga flux ratio = 15. Our results show that the nonradiative lifetime and internal radiative quantum efficiency of the DH structures grown using these parameters are comparable to those of the highest quality reported MBE-grown GaAs.

关键词：铝镓砷化物；外延生长；量子效率；太阳能电池

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A pre-irradiation grafting method is a fascinating technique for direct introduction of new functional graft polymers (grafts) into polymer substrates without any damages. The radiation technique has been widely applied to the preparation of high performance fuel cell polymer electrolyte membranes (PEMs) for mobile electricities, vehicles, and domestic co-generation systems. The PEMs of aromatic hydrocarbon polymers, so-called "super engineering plastics" including poly (ether ether ketone) (PEEK), have useful characteristics such as high mechanical strength, gas barrier property, and radiation resistance. Thus, in this work, we investigated the humidity dependence of proton conductivity and mechanical strength at 80 ℃ and relative humidity (RH) from 30 to 95%, which are the most important characteristics for power generation efficiency and durability under real operating conditions in fuel cell systems.

关键词：燃料电池；电解质材料；聚合物

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Our main project objective was to implement Plug-in Electric Vehicles (PEV) and charging infrastructure into our electric distribution service territory and help reduce barriers in the process. Our research demonstrated the desire for some to be early adopters of electric vehicles and the effects lack of education plays on others. The response of early adopters was tremendous: with the initial launch of our program we had nearly 60 residential customers interested in taking part in our program. However, our program only allowed for 15 residential participants. Our program provided assistance towards purchasing a PEV and installation of Electric Vehicle Supply Equipment (EVSE). The residential participants have all come to love their PEVs and are more than enthusiastic about promoting the many benefits of driving electric.

关键词：混合动力；电动汽车；电池充电；推进系统

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Various modes of severe plastic deformation (SPD), such as high-pressure torsion (HPT) at cryogenic temperature, equal channel angular pressing (ECAP) and dynamic channel-angular pressing (DCAP), have been applied for nanostructuring of Ni, and the thermal stability of the structure obtained has been studied. The nanocrystalline structure with average grain sizes of 80 nm and the microhardness of 6200 MPa is produced by HPT in liquid nitrogen. DCAP and ECAP result in the submicrocrystalline structure of a mixed type, with ultra-fine grains separated by high-angle boundaries along with deformation bands and coarse cells with low-angle dislocation boundaries. The thermal stability of the structures obtained by ECAP and DCAP is approximately the same, and it is higher than after the HPT at cryogenic temperature.

关键词：电极材料；纳米晶体；塑性形变

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