It is shown by magnetic field dependent ac susceptibility, magnetic force microscopy, and ferromagnetic resonance that exposure of C(sub 60) to fluorine at 160 deg C produces a stable ferromagnetic material with a Curie temperature well above room temperature. The exposure to fluorine is accomplished by decomposing a fluorine rich polymer, trifluorochloroethylene, F(sub 2) (C-CFCl)(sub n) which has C(sub 60) imbedded in it. Based on previous experimental observations and molecular orbital calculations, it is suggested that the ferromagnetism is arising from crystals of C(sub 60)-F.

关键词：铁磁性；铁磁谐振；聚合物；拉曼光谱

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Metamaterials are artificially constructed materials. When electromagnetic waves propagate through metamaterials they display properties different from those found in natural materials. These different properties can include negative refraction (light is bent in the opposite direction from that expected from general laws of physics), flat lens focusing, and subwavelength imaging. The use of meta-materials to direct electromagnetic beams is a highly promising approach to overcome current limitations of conformal antennas by improving the radiation characteristics of antenna elements, especially those at the edge of phased array antennas.

关键词：超材料；碳纳米管；保形天线；镜片；高分子材料

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The development of a bulk nano-grained tungsten material has been the subject of ongoing research at the U.S. Army Research Laboratory (ARL), Aberdeen Proving Ground, MD. While it has been shown that a powder metallurgy approach can lead to bulk nano-grained tungsten material, it has been a persistent challenge to achieve full density. Commercially available tungsten must undergo complex multi-step processes (both hot and cold working) to obtain a fully dense part. Similar procedures may need to be developed to produce fully dense nano-crystalline tungsten. One problem with post-processing procedures is that bulk nano-grained materials are often less ductile than their large grained counterparts. With conventional commercial tungsten, the brittle nature of the material is overcome by incorporating multi-step hot working procedures. However, for nano-tungsten, recrystallization and grain growth become an issue during processing at elevated temperatures. Commercially, rhenium is often added to tungsten to improve ductility and high temperature stability. By adding rhenium to nano-tungsten, enough ductility might be developed to allow for hot working at temperatures low enough to prevent grain growth. Prior to swaging, it needs to be determined whether or not the rhenium addition does impart ductility to nano-tungsten and, if so, at what temperatures and conditions. In order to test the mechanical properties of nano- tungsten with rhenium at high temperatures, the Gleeble unit (a digital version of the 1500 model produced by Dynamic Systems Incorporated, Poestenkill, New York) at ARL was used. The Gleeble is a process simulation machine designed to mimic the thermal and mechanical conditions that arise during processing.

关键词：粉末冶金；钨；细粒物料；冷加工

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The National Institute for Occupational Safety and Health (NIOSH) Engineering and Physical Hazards Branch (EPHB) and the University of Massachusetts Lowell (UMass Lowell) Environmental Health and Safety Team assessed nanoparticle emissions in a chemical laboratory at UMass Lowell. The laboratory conducted bench-top scale product development using 20-30 nm diameter bundles of single-walled carbon nanotubes (CNTs). The tasks evaluated in this study included weighing, mixing, sonicating, coating, drying, and cutting, which are common activities in most research and commercial production facilities. Weigh-out, mixing, and sonication were conducted on the bench-top without engineering controls, while coating, drying, and cutting were conducted inside a fume hood or a ventilated enclosure. The study results provide information on exposure potential and control for common nanomanufacturing processes.

关键词：空气污染；空气污染监测；碳纳米管；纳米颗粒；排放量

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In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot- and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

关键词：生物质热解；催化剂；化学分析；转换；生物质能

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In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot- and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. The economic results of these analyses are in the process of further refinement and will be published in FY13 and FY14 design reports. This report summarizes the preliminary technical data used for the models and identified data gaps. This technology pathway case investigates the cultivation of algal biomass followed by further lipid extraction and upgrading to hydrocarbon biofuels. Technical barriers and key research needs have been assessed in order for the algal lipid extraction and upgrading pathway to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.

关键词：藻类;血脂;提取;烃;生物质种植;生物质能

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We use x-ray spectroscopy and density functional theory to investigate the hydrogenation-induced electronic structure changes in graphene on Pt(111). The atom-specific properties of the spectroscopy allow for a direct projection of the band structure onto the carbon atoms; this was compared with the calculated density of states. Instead of the generally expected band opening behavior, we observe states at the Fermi level in the carbon-projected density of states. Hydrogenation is accompanied by pinning of the graphene to the substrate through the formation of local CPt bonds which cause the graphene layer to become metallic upon hydrogenation.

关键词：加氢；可逆；石墨烯

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CO2 hydrogenation to olefins and ethylene oligomerization was investigated in efforts to improve catalyst composition and reaction conditions needed for scale-up. The hydrogenation of CO2 to hydrocarbons is investigated over -alumina-supported iron-based catalysts modified with manganese and potassium promoters and a silica-stabilized coating under fixed-bed reactor conditions to produce unsaturated hydrocarbons as feedstock chemicals for jet fuel synthesis. The stabilizer is introduced by impregnating the K/Mn/Fe on Al2O3 catalyst with tetraethylorthosilicate (TEOS) to minimize the deactivating effects of water on catalyst activity in CO2 hydrogenation. The K/Mn/Fe on Al2O3 catalyst modified with the TEOS and reduced in CO produced a lighter end fraction of olefins compared with the catalyst reduced in H2. To increase the chain length of the olefins formed in the CO2 hydrogenation step, investigation of oligomerization reaction is conducted in a separate experiment, where pure ethylene is used as a model olefin. Ethylene oligomerization over pelletized amorphous silica-alumina (ASA)-supported Ni catalysts demonstrated high conversion and selectivity towards the jet fuel fraction (C8-C16) at very low MHSV.

关键词：加氢；二氧化碳；氢；两步骤过程

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Organophosphate compounds are used as pesticides and in chemical warfareagents such as nerve agents. VX ((O-ethyl S- 2-(diisopropylamino)ethyl) methylphosphonothioate) is one of the most toxic and environmentally persistent of these nerve agents. This research examined the fate of malathion, a pesticide and surrogate of VX O-ethyl S- 2-(diisopropylamino) (ethyl)(methylphosphonothioate), in bench-scale activated sludge (AS) sequencing batch reactors. Sorption kinetics and sorption equilibrium isotherm experiments indicate that sorption to AS biomass was not a statistically important removal mechanism. However, approximately 90of the initial 4.25 mg L-1 malathion concentration degraded primarily via heterotrophic activity.

关键词：农药；马拉硫磷；活性泥；污水处理；有机磷农药

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The HHE Program evaluated surface contamination from spills of sea lamprey pesticides that occurred in the 1960s and 1970s at a biological station. HHE Program investigators took samples of carpet that were thought to have been contaminated with pesticide and took wipe samples from surfaces. Yellow stains were seen on carpet, walls, and unsealed concrete floors. The carpet had been installed over unsealed concrete. Pesticide was found on the carpet and wipe samples from areas that were visibly stained. HHE Program investigators recommended that the stained carpet be removed and that the concrete slab floor be cleaned and sealed prior to the installation of new flooring. Walls that had visible stains should be cleaned, sealed, and repainted. Investigators also measured temperature, relative humidity, carbon monoxide, and carbon dioxide and checked the heating, ventilation, and air-conditioning system in the offices and laboratory. Room air flowed from the offices into the workshop which helped keep potentially contaminated air from entering the office space. The exhaust fan in the laboratory solvent storage room was not always turned on which allowed air to flow into the nearby laboratory. This fan should be run continuously to reduce the amount of solvent vapors that can enter nearby work areas. Investigators recommended that the employer stop sampling soil and concrete that may have been contaminated during past spills. Employees were encouraged to wash their hands with soap and water after handling pesticides and avoid touching surfaces that are visibly stained. Employees should not go into offices while wearing clothes, shoes, or materials that may have pesticides on them. Investigators also recommended that the employer notify all employees about plans to renovate the building and follow up with employees after projects are completed to ensure that these activities have eliminated visible pesticide contamination on carpet, floors, and walls.

关键词：农药；健康风险；农药污染；生物站；海七鳃鳗

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