WorldWideScience

Sample records for research area silicon

  1. LASSA: Large Area Silicon Strip Array

    Science.gov (United States)

    Davin, B.; Desouza, R. T.; Yanez, R.; Church, J.; Gelbke, C. K.; Liu, T.; Lynch, W. G.; Moehlenkamp, T.; Tan, T.; Tsang, M. B.; Wagner, A.; Charity, R. J.; Sarantites, D. G.; Sobotka, L. G.

    1998-04-01

    An IU-MSU-WU collaboration is designing and building a new array for detecting isotopically resolved intermediate mass fragments (IMF: 3<=Z<=10) and light charged particles (LCP: Z<=2) with good spatial resolution and low energy thresholds. The first element of each telescope consists of a 5 cm x 5 cm 65 μ m passivated silicon detector. This thin silicon detector is backed by a 500 μ m detector of the same area. These silicon detectors are mounted in a compact geometry which minimizes dead area. To allow detection of LCP, the silicon detectors are backed by 6 cm thick CsI(Tl) crystals with photodiode readout. The 65 μ m silicon has 16 strips on its front surface while the 500 μ m has 16 strips on the front surface with an additional 16 strips oriented orthogonally on the back surface which allows two dimensional position information for both IMFs and LCPs. The array has nine telescopes in a 3x3 arrangement to optimize the measurement of small angle IMF-IMF coincidences in heavy-ion induced multifragmention reactions. Design details, efficiency calculations, and early prototype results will be presented.

  2. Research Areas: Liver Disease

    Science.gov (United States)

    ... Advisors, and committees that coordinate research activities Research Areas Overview of NIDDK activities in each major research area, including research advances, research coordination, and health information ...

  3. Low Cost Solar Array Project cell and module formation research area. Process research of non-CZ silicon material. Final report, November 26, 1980-September 30, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, R.B.

    1983-01-01

    The primary objective of the work reported was to investigate high-risk, high-payoff research areas associated with the Westinghouse process for producing photovoltaic modules using non-Czochralski sheet material. These tasks were addressed: technical feasibility study of forming front and back junctions using liquid dopant techniques, liquid diffusion mask feasibility study, application studies of antireflective material using a meniscus coater, ion implantation compatibility/feasibility study, and cost analysis. (LEW)

  4. University Crystalline Silicon Photovoltaics Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    Ajeet Rohatgi; Vijay Yelundur; Abasifreke Ebong; Dong Seop Kim

    2008-08-18

    The overall goal of the program is to advance the current state of crystalline silicon solar cell technology to make photovoltaics more competitive with conventional energy sources. This program emphasizes fundamental and applied research that results in low-cost, high-efficiency cells on commercial silicon substrates with strong involvement of the PV industry, and support a very strong photovoltaics education program in the US based on classroom education and hands-on training in the laboratory.

  5. Ice Engineering Research Area

    Data.gov (United States)

    Federal Laboratory Consortium — Refrigerated Physical Modeling of Waterways in a Controlled EnvironmentThe Research Area in the Ice Engineering Facility at the Cold Regions Research and Engineering...

  6. Silicon-based microreactors as research tools in chemistry

    NARCIS (Netherlands)

    Tiggelaar, Roald M.; Gardeniers, Johannes G.E.; van den Berg, Albert

    In this contribution suitability of silicon-technology based microreactors for performing research on reactions where temperature control is essential is discussed. The versatility of silicon micromachining technology is elucidated by describing the fabrication and performance of two types of

  7. Basic research challenges in crystalline silicon photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Werner, J.H. [Max-Planck-Institut fuer Festkoerperforschung, Stuttgart (Germany)

    1995-08-01

    Silicon is abundant, non-toxic and has an ideal band gap for photovoltaic energy conversion. Experimental world record cells of 24 % conversion efficiency with around 300 {mu}m thickness are only 4 % (absolute) efficiency points below the theoretical Auger recombination-limit of around 28 %. Compared with other photovoltaic materials, crystalline silicon has only very few disadvantages. The handicap of weak light absorbance may be mastered by clever optical designs. Single crystalline cells of only 48 {mu}m thickness showed 17.3 % efficiency even without backside reflectors. A technology of solar cells from polycrystalline Si films on foreign substrates arises at the horizon. However, the disadvantageous, strong activity of grain boundaries in Si could be an insurmountable hurdle for a cost-effective, terrestrial photovoltaics based on polycrystalline Si on foreign substrates. This talk discusses some basic research challenges related to a Si based photovoltaics.

  8. Silicon-on-ceramic coating process. Silicon sheet growth development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Silicon Solar Array Project. Quarterly report No. 8, December 28, 1977--March 28, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W. Zook, J.D.; Heaps, J D; Maclolek, R B; Koepke, B; Butter, C D; Schult, S B

    1978-04-20

    A research program to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon is described. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 12 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A dip-coating method for putting silicon on ceramic (SOC) has been shown to produce solar-cell-quality sheet silicon. This method and a continuous coating process also being investigated have excellent scale-up potential which offers an outstanding cost-effective way to manufacture large-area solar cells. A variety of ceramic materials have been dip-coated with silicon. The investigation has shown that mullite substrates containing an excess of SiO/sub 2/ best match the thermal expansion coefficient of silicon and hence produce the best SOC layers. With such substrates, smooth and uniform silicon layers 25 cm/sup 2/ in area have been achieved with single-crystal grains as large as 4 mm in width and several cm in length. Solar cells with areas from 1 to 10 cm/sup 2/ have been fabricated from material withas-grown surface. Recently, an antireflection (AR) coating has been applied to SOC cells. Conversion efficiencies greater than 9% have been achieved without optimizing series resistance characteristics. Such cells typically have open-circuit voltages and short-circuit current densities of 0.51 V and 20 mA/cm/sup 2/, respectively.

  9. Large-area silicon nanowires from silicon monoxide for solar cell applications.

    Science.gov (United States)

    Zhang, Ming-Liang; Mahmood, Iram; Fan, Xia; Xu, Gang; Wong, Ning-Bew

    2010-12-01

    Large-area upstanding silicon nanowires (SiNWs) were synthesized by hot-filament chemical vapor deposition (HFCVD) using silicon monoxide (SiO) powder as Si source under high vacuum (1.2 x 10(-5) Torr). Gold nanoparticles (AuNPs) were employed as catalyst, which were formed on Si substrate by in-situ reduction of gold chloride (AuCl3). The size and distribution of the Au nanoparticles can be easily controlled through chemical reaction conditions. Consequently, the diameter, length and density of SiNWs could be varied in certain range. The SiNWs obtained are single crystalline with growth directions predominantly along [01-1]. Silicon nanowires in large-scale and diameter less than 10 nm can be grown on different Si substrates with this method. Organic inorganic hybrid solar cells based on SiNWs arrays have been demonstrated.

  10. Low cost silicon solar array project large area silicon sheet task: Silicon web process development

    Science.gov (United States)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Blais, P. D.; Davis, J. R., Jr.

    1977-01-01

    Growth configurations were developed which produced crystals having low residual stress levels. The properties of a 106 mm diameter round crucible were evaluated and it was found that this design had greatly enhanced temperature fluctuations arising from convection in the melt. Thermal modeling efforts were directed to developing finite element models of the 106 mm round crucible and an elongated susceptor/crucible configuration. Also, the thermal model for the heat loss modes from the dendritic web was examined for guidance in reducing the thermal stress in the web. An economic analysis was prepared to evaluate the silicon web process in relation to price goals.

  11. Selective-area laser deposition (SALD) Joining of silicon carbide with silicon carbide filler

    Science.gov (United States)

    Harrison, Shay Llewellyn

    Selective Area Laser Deposition (SALD) is a gas-phase, solid freeform fabrication (SFF) process that utilizes a laser-driven, pyrolytic gas reaction to form a desired solid product. This solid product only forms in the heated zone of the laser beam and thus can be selectively deposited by control of the laser position. SALD Joining employs the SALD method to accomplish 'welding' of ceramic structures together. The solid reaction product serves as a filler material to bond the two parts. The challenges involved with ceramic joining center around the lack of a liquid phase, little plastic deformation and diffusivity and poor surface wetting for many ceramic materials. Due to these properties, traditional metal welding procedures cannot be applied to ceramics. Most alternative ceramic welding techniques use some form of a metal addition to overcome these material limitations. However, the metal possesses a lower ultimate use temperature than the ceramic substrate and therefore it decreases the temperature range over which the joined part can be safely used. SALD Joining enjoys several advantages over these ceramic welding procedures. The solid filler material chemistry can be tailored to match the type of ceramic substrate and therefore fabricate monolithic joints. The SALD filler material bonds directly to the substrate and the joined structure is made in a one step process, without any post-processing. The research documented in this dissertation focused on SALD Joining of silicon carbide structures with silicon carbide filler material. A historical progression of gas-phase SFF research and a literature review of the most prominent ceramic joining techniques are provided. A variety of SiC substrates were examined, as were various conditions of gas precursor pressures and mixtures, laser beam scan speed and joint configuration. The SALD material was characterized for composition and structure by x-ray diffraction, transmission electron microscopy and nuclear magnetic

  12. Large area amorphous silicon x-ray imagers

    Science.gov (United States)

    Street, R. A.; Wu, X. D.; Weisfield, R.; Ready, S.; Apte, R.; Nguyen, M.; Nylen, P.

    Large two dimensional amorphous silicon imaging arrays are of interest for electronic document input and x-ray imaging. The device is a matrix-addressed array of light detectors fabricated from hydrogenated amorphous silicon on a glass substrate. Each imaging pixel consists of a light sensor and a thin film transistor (TFT). X-ray imaging is accomplished by placing a phosphor in contact with the image sensing surface, or by direct detection with a thick photoconductor. The imager technology is now capable of 10 in. arrays with image capture at greater than 10 frames/sec and with resolution of 4-6 lp/mm. We describe our new high resolution imaging system, comprising the sensor array with an active area of approximately 8 × 10 in. having nearly 3 million pixels, and the accompanying readout electronics. Key technological issues and alternative array designs are discussed.

  13. Research Areas - Clinical Trials

    Science.gov (United States)

    Information about NCI programs and initiatives that sponsor, conduct, develop, or support clinical trials, including NCI’s Clinical Trial Network (NCTN) and NCI Community Oncology Research Program (NCORP) initiatives.

  14. Research Areas: Diagnosis

    Science.gov (United States)

    Accurate information derived from diagnostic tools is crucial for making decisions at all stages of cancer care. NCI supports research on the development of tests and imaging technologies that can provide specific information about an individual’s cancer.

  15. Research and Application Progress of Silicone Rubber Materials in Aviation

    Directory of Open Access Journals (Sweden)

    HUANG Yanhua

    2016-06-01

    Full Text Available The research progress of heat resistance, cold resistance, electrical conductivity and damping properties of aviation silicone rubber were reviewed in this article. The heat resistance properties of silicone rubber can be enhanced by changing the molecular structure (main chain, end-group, side chain and molecular weight of the gum and adding special heat-resistance filler. The cold resistance of aviation silicone rubber can be enhanced by adjusting the side chain molecular structure of the gum and the content of different gum chain. The electrical conductivity of silicone rubber can be improved by optimizing, blending and dispersing of conductive particles. The damping property of silicone rubber can be improved by designing and synthesizing of high-molecular polysiloxane damping agent. Furthermore, the application of aviation silicone rubber used in high-low temperature seal, electrical conduction and vibration damping technology are also summarized, and the high performance (for example long-term high temperature resistance, ultralow temperature resistance, high electromagnetic shelding, long-term fatigue resistance vibration damping, quasi constant modulus and so on of special silicone rubber is the future direction of aviation silicone rubber.

  16. Research Paper Silicon alleviates salt stress, decreases ...

    African Journals Online (AJOL)

    A greenhouse experiment was conducted to investigate the effects of different levels of silicon (Si) application on cut rose (Rosa xhybrida L.) 'Hot Lady' under two levels of salt stress. Four Si concentrations (0, 50, 100 and 150 ppm) as Si were combined with a 25 mM NaCl (EC 3.8) level in the nutrient solution supplied to ...

  17. Silicon on ceramic process. Silicon sheet growth development for the Large-Area Silicon Sheet Task of the Low-Cost Silicon Solar Array Project. Annual report No. 2, September 17, 1976--September 19, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Zook, J.D.; Heaps, J.D.; Maciolek, R.B.; Koepke, B.; Butter, C.D.; Schuldt, S.B.

    1977-09-30

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. In the past year significant progress was made in all areas of the program. The physical and chemical properties of the standard mullite refractory used for the majority of the coating runs (McDanel MV20 and Coors S1SI) have been characterized. A number of experimental compositions have been identified and procured from Coors. Characterization of the standard compositions revealed that the thermal expansion of mullite depends on both relative amounts of glass phase and on the impurity level in the glass. Since the thermal expansion in mullite exceeds that of silicon, the silicon coating should be in a state of compression. This was confirmed by x-ray measurements. After modifying and cleaning the dip-coating facility, silicon on ceramic (SOC) solar cells were fabricated which demonstrate that the SOC process can produce silicon of solar cell quality. SOC cells having 1 cm/sup 2/ active areas demonstrated measured conversion efficiencies as high as 7.2 percent. Typical open-ciruit voltages (V/sub oc/) and short-circuit current densities (J/sub sc/) were 0.51 volt and 20 mA/cm/sup 2/, respectively. Since the active surface of these solar cells is a highly reflective ''as-grown'' surface, one can expect improvement in J/sub sc/ after an anti-reflection (AR) coating is applied. Results of an economic analysis of the SOC process are presented.

  18. Silicon on ceramic process. Silicon sheet growth for Large-Area Silicon Sheet Task of the Low-Cost Solar Array Project. Annual report No. 4, September 29, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P W; Zook, J D; Heaps, J D; Koepke, B; Grung, B L; Schuldt, S B

    1979-10-31

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. The effort is divided into several areas of investigation in order to most efficiently meet the goals of the program. These areas include: (1) dip-coating; (2) continuous coating; (3) material characterization; (4) cell fabrication; and (5) theoretical analysis. Progress in all areas of the program is reported in detail. (WHK)

  19. Silicon-on ceramic process. Silicon sheet growth and device developmentt for the Large-Area Silicon Sheet Task of the Low-Cost Solar Array Project. Quarterly report No. 13, October 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P W; Zook, J D; Grung, B L; McHenry, K; Schuldt, S B

    1980-02-15

    Research on the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon is reported. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 11 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A variety of ceramic materials have been dip coated with silicon. The investigation has shown that mullite substrates containing an excess of SiO/sub 2/ best match the thermal expansion coefficient of silicon and hence produce the best SOC layers. With such substrates, smooth and uniform silicon layers 25 cm/sup 2/ in area have been achieved with single-crystal grains as large as 4 mm in width and several cm in length. Crystal length is limited by the length of the substrate. The thickness of the coating and the size of the crystalline grains are controlled by the temperature of the melt and the rate at which the substrate is withdrawn from the melt. The solar-cell potential of this SOC sheet silicon is promising. To date, solar cells with areas from 1 to 10 cm/sup 2/ have been fabricated from material with an as-grown surface. Conversion efficiencies of about 10 percent with antireflection (AR) coating have been achieved. Such cells typically have open-circuit voltage and short-circuit current densities of 0.55V and 23 mA/cm/sup 2/, respectively.

  20. The STAR silicon vertex tracker: a large area silicon drift detector

    CERN Document Server

    Lynn, D; Beuttenmüller, Rolf H; Caines, H; Chen, W; Dimassimo, D; Dyke, H; Elliot, D; Eremin, V; Grau, M; Hoffmann, G W; Humanic, T; Ilyashenko, Yu S; Kotov, I; Kraner, H W; Kuczewski, P; Leonhardt, B; Li, Z; Liaw, C J; Lo Curto, G; Middelkamp, P; Minor, R; Munhoz, M; Ott, G; Pandey, S U; Pruneau, C A; Rykov, V L; Schambach, J; Sedlmeir, J; Soja, B; Sugarbaker, E R; Takahashi, J; Wilson, K; Wilson, R

    2000-01-01

    The Solenoidal Tracker At RHIC-Silicon Vertex Tracker (STAR-SVT) is a three barrel microvertex detector based upon silicon drift detector technology. As designed for the STAR-SVT, silicon drift detectors (SDDs) are capable of providing unambiguous two-dimensional hit position measurements with resolutions on the order of 20 mu m in each coordinate. Achievement of such resolutions, particularly in the drift direction coordinate, depends upon certain characteristics of silicon and drift detector geometry that are uniquely critical for silicon drift detectors hit measurements. Here we describe features of the design of the STAR-SVT SDDs and the front-end electronics that are motivated by such characteristics.

  1. Silicon-on-ceramic process: silicon sheet growth and device development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Solar Array Project. Quarterly report No. 11, January 1-March 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W.; Zook, J.D.; Heaps, J.D.; Grung, B.L.; Koepke, B.; Schuldt, S.B.

    1979-04-30

    The purpose of the research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 12 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A dip-coating method for putting silicon on ceramic (SOC) has been shown to produce solar-cell-quality sheet silicon. This method and a continuous coating process also being investigated have excellent scale-up potential which offers an outstanding, cost-effective way to manufacture large-area solar cells. Results and accomplishments are described.

  2. Silicon integrated circuits advances in materials and device research

    CERN Document Server

    Kahng, Dawon

    1981-01-01

    Silicon Integrated Circuits, Part B covers the special considerations needed to achieve high-power Si-integrated circuits. The book presents articles about the most important operations needed for the high-power circuitry, namely impurity diffusion and oxidation; crystal defects under thermal equilibrium in silicon and the development of high-power device physics; and associated technology. The text also describes the ever-evolving processing technology and the most promising approaches, along with the understanding of processing-related areas of physics and chemistry. Physicists, chemists, an

  3. Silicon-on ceramic process. Silicon sheet growth and device development for the large-area silicon sheet and cell development tasks of the low-cost solar array project. Quarterly report No. 12, April 2, 1979-June 29, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W.; Zook, J.D.; Heaps, J.D.; Grung, B.L.; Koepke, B.; Schuldt, S.B.

    1979-07-31

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon. We plan to do this by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. During the quarter, significant progress was demonstrated in several areas: (1) a 10-cm/sup 2/ cell having 9.9 percent conversion efficiency (AM1, AR) was fabricated; (2) the Honeywall-sponsored SCIM coating development succeeded in producing a 225-cm/sup 2/ layer of sheet silicon (18 inches x 2 inches); and (3) 100 ..mu..m-thick coatings at pull speed of 0.15 cm/sec wer$obta9ned, although apoproximately 50 percent of the layer exhibited dendritic growth. Other results and accomplishments during the quarter are reported in detail. (WHK)

  4. Large area sheet task. Advanced dendritic web growth development. [silicon films

    Science.gov (United States)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Hopkins, R. H.; Meier, D.; Frantti, E.; Schruben, J.

    1981-01-01

    The development of a silicon dendritic web growth machine is discussed. Several refinements to the sensing and control equipment for melt replenishment during web growth are described and several areas for cost reduction in the components of the prototype automated web growth furnace are identified. A circuit designed to eliminate the sensitivity of the detector signal to the intensity of the reflected laser beam used to measure melt level is also described. A variable speed motor for the silicon feeder is discussed which allows pellet feeding to be accomplished at a rate programmed to match exactly the silicon removed by web growth.

  5. High surface area silicon carbide-coated carbon aerogel

    Science.gov (United States)

    Worsley, Marcus A; Kuntz, Joshua D; Baumann, Theodore F; Satcher, Jr, Joe H

    2014-01-14

    A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust. Carbon aerogels can be coated with sol-gel silica and the silica can be converted to silicone carbide, improved the thermal stability of the carbon aerogel.

  6. Dip-coating process. Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project. Quarterly report No. 7

    Energy Technology Data Exchange (ETDEWEB)

    Zook, J.D.; Heaps, J.D.; Maciolek, R.B.; Koepke, B.; Butter, C.D.; Schuldt, S.B.

    1977-12-30

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. During the past quarter, significant progress was demonstrated in several areas. Seeded growth of silicon-on-ceramic (SOC) with an EFG ribbon seed was demonstrated. Different types of mullite received from Coors were successfully coated with silicon. A new method of deriving minority carrier diffusion length, L/sub n/, from spectral response measurements was evaluated. ECOMOD cost projections were found to be in good agreement with the interim SAMIS method proposed by JPL. On the less positive side, there was a decrease in cell performance which is believed to be due to an unidentified source of impurities. Also, operation of the new coating system fell behind schedule but is expected to improve in the coming quarter, since construction has now been completed.

  7. Application research on the sensitivity of porous silicon

    Science.gov (United States)

    Xu, Gaobin; Xi, Ye; Chen, Xing; Ma, Yuanming

    2017-09-01

    Applications based on sensitive property of porous silicon (PSi) were researched. As a kind of porous material, the feasibility of PSi as a getter material was studied. Five groups of samples with different parameters were prepared. The gas-sensing property of PSi was studied by the test system and suitable parameters of PSi were also discussed. Meanwhile a novel structure of humidity sensor, using porous silicon as humidity-sensitive material, based on MEMS process has been successfully designed. The humidity-sensing properties were studied by a test system. Because of the polysilicon layer deposited upon the PSi layer, the humidity sensor can realize a quick dehumidification by itself. To extend service life and reduce the effect of the environment, a passivation layer (Si3N4) was also deposited on the surface of electrodes. The result indicated the novel humidity sensor presented high sensitivity (1.1 pF/RH%), low hysteresis, low temperature coefficient (0.5%RH/°C) and high stability.

  8. Hydrogen-terminated mesoporous silicon monoliths with huge surface area as alternative Si-based visible light-active photocatalysts

    KAUST Repository

    Li, Ting

    2016-07-21

    Silicon-based nanostructures and their related composites have drawn tremendous research interest in solar energy storage and conversion. Mesoporous silicon with a huge surface area of 400-900 m2 g-1 developed by electrochemical etching exhibits excellent photocatalytic ability and stability after 10 cycles in degrading methyl orange under visible light irradiation, owing to its unique mesoporous network, abundant surface hydrides and efficient light harvesting. This work showcases the profound effects of surface area, crystallinity, pore topology on charge migration/recombination and mass transportation. Therein the ordered 1D channel array has outperformed the interconnected 3D porous network by greatly accelerating the mass diffusion and enhancing the accessibility of the active sites on the extensive surfaces. © 2016 The Royal Society of Chemistry.

  9. Analysis of defect structure in silicon. Silicon sheet growth development for the large area silicon sheet task of the Low-Cost Solar array Project

    Science.gov (United States)

    Natesh, R.; Mena, M.; Plichta, M.; Smith, J. M.; Sellani, M. A.

    1982-01-01

    One hundred ninety-three silicon sheet samples, approximately 880 square centimeters, were analyzed for twin boundary density, dislocation pit density, and grain boundary length. One hundred fifteen of these samples were manufactured by a heat exchanger method, thirty-eight by edge defined film fed growth, twenty-three by the silicon on ceramics process, and ten by the dendritic web process. Seven solar cells were also step-etched to determine the internal defect distribution on these samples. Procedures were developed or the quantitative characterization of structural defects such as dislocation pits, precipitates, twin & grain boundaries using a QTM 720 quantitative image analyzing system interfaced with a PDP 11/03 mini computer. Characterization of the grain boundary length per unit area for polycrystalline samples was done by using the intercept method on an Olympus HBM Microscope.

  10. Dip coating process. Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project. Quarterly report No. 6, March 22, 1977--June 24, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Zook, J.D.; Heaps, J.D.; Maciolek, R.B.; Koepke, B.; Butter, C.D.; Schuldt, S.B.

    1977-06-30

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. Significant progress was made in silicon on ceramic (SOC) solar cell performance. SOC cells having 1 cm/sup 2/ active areas demonstrated measured conversion efficiencies as high as 7.2 percent. Typical open circuit voltages (V/sub oc/) and short circuit current densities (J/sub sc/) were 0.51 volt and 20 mA/cm/sup 2/ respectively. Since the active surface of these solar cells is a highly reflective ''as-grown'' surface, one can expect improvement in J/sub sc/ after an anti-reflection (AR) coating is applied. It is significant that single-crystal comparison cells, also measured without benefit of an AR coating, had efficiencies in the 8.5 percent range with typical V/sub oc/'s and J/sub sc/'s of 0.54 volt and 23 mA/cm/sup 2/, respectively. Therefore, improvement in cell design and junction diffusion techniques should increase the efficiency of both the SOC and single-crystal cells. During this quarter the dip coating facility was inadvertently contaminated, but has since been restored to a purity level exceeding its original state. With this facility, silicon coatings were grown with a single-crystal seed attached to the substrate. Single-crystal silicon was not forthcoming, but the results were nonetheless encouraging. Several of the carbon coating types tried appear promising, including one which has high purity and can be applied uniformly by swab or airbrush.

  11. Thermal and hydrodynamic studies for micro-channel cooling for large area silicon sensors in high energy physics experiments

    Science.gov (United States)

    Flaschel, Nils; Ariza, Dario; Díez, Sergio; Gerboles, Marta; Gregor, Ingrid-Maria; Jorda, Xavier; Mas, Roser; Quirion, David; Tackmann, Kerstin; Ullan, Miguel

    2017-08-01

    Micro-channel cooling initially aiming at small-sized high-power integrated circuits is being transferred to the field of high energy physics. Today's prospects of micro-fabricating silicon opens a door to a more direct cooling of detector modules. The challenge in high energy physics is to save material in the detector construction and to cool large areas. In this paper, we are investigating micro-channel cooling as a candidate for a future cooling system for silicon detectors in a generic research and development approach. The work presented in this paper includes the production and the hydrodynamic and thermal testing of a micro-channel equipped prototype optimized to achieve a homogeneous flow distribution. Furthermore, the device was simulated using finite element methods.

  12. Experience with silicon sensor performance and quality control for a large-area detector

    CERN Document Server

    Krammer, M

    2003-01-01

    The CMS silicon tracker, at present under construction, will consist of 10 barrel layers and 2 multiplied by 9 end cap discs inside a volume of about 5.6 m length and 2.4 m radius. The total sensitive area covered by silicon will exceed 200 m**2. To cope with the expected radiation damage induced by the particle fluence at the Large Hadron Collider the detector will be operated at -10 degree C. Two companies manufacture the 25000 silicon sensors in 15 different geometries. The delivery of the sensors is under way and hence an extensive quality control program for the sensors has been put in operation. The paper gives an overview of the CMS tracker system and subsequently concentrates on the results from the sensor tests. In addition, measurements on dedicated test structures are presented which were designed to monitor the stability of the sensor production process.

  13. [Research progress about the relationship between nanoparticles silicon dioxide and lung cancer].

    Science.gov (United States)

    Dai, Chun; Huang, Yunchao; Zhou, Yongchun

    2014-10-20

    Nano-silicon dioxide widely distributed in plastic, rubber, ceramics, paint, adhesives, and many other fields, and it is the product of coal combustion. A growing evidence shows that nano-silicon dioxide has certain correlation with respiratory system disease. In this paper, we synthesized existing researches of domestic and abroad, summarized the lung toxicity of nanoparticles. This article are reviewed from the physical and chemical properties of nanoparticles silicon dioxide, exposure conditions and environment, and the pathogenic mechanism of nano-silicon dioxide.

  14. Research Progress about the Relationship between Nanoparticles Silicon Dioxide and Lung Cancer

    Directory of Open Access Journals (Sweden)

    Chun DAI

    2014-10-01

    Full Text Available Nano-silicon dioxide widely distributed in plastic, rubber, ceramics, paint, adhesives, and many other fields, and it is the product of coal combustion. A growing evidence shows that nano-silicon dioxide has certain correlation with respiratory system disease. In this paper, we synthesized existing researches of domestic and abroad, summarized the lung toxicity of nanoparticles. This article are reviewed from the physical and chemical properties of nanoparticles silicon dioxide, exposure conditions and environment, and the pathogenic mechanism of nano-silicon dioxide.

  15. Large-area silicon nanowire Schottky junction photodetector with tunable absorption and low junction capacitance

    Science.gov (United States)

    Hackett, L. P.; Seyedi, M. A.; Fiorentino, M.; Beausoleil, R. G.

    2017-06-01

    Silicon photodetectors for operation in the near-infrared with a sufficient responsivity and high-speed operation are currently needed as scalable, CMOS compatible components for photonic and communication applications. Photodetectors based on semiconductor nanowire structures with dielectric planarization enable larger active optical areas and higher operating speeds than planar devices due to reduced junction capacitance and enhanced absorption. Here, we report on the fabrication and characterization of a silicon nanowire photodetector with dielectric infilling and a transparent indium tin oxide (ITO) Schottky contact. Optical simulations show that the absorbed power can be confined at the top of the nanowire array, enabling efficient operation in the near-infrared. This is despite the relatively low absorption coefficient for silicon in this wavelength range in addition to the design of the nanowire array to have a low fill factor compared to the bulk material in order to minimize the junction capacitance. The responsivity of this device is  >0.3 A W-1 at a reverse bias of 2 V and the junction capacitance is 8  ±  2 nF cm-2, which are respectively comparable and lower than the values expected for a planar silicon Schottky junction photodetector with a similar active area.

  16. Nanostructure formation and passivation of large-area black silicon for solar cell applications.

    Science.gov (United States)

    Liu, Yaoping; Lai, Tao; Li, Hailing; Wang, Yan; Mei, Zengxia; Liang, Huili; Li, Zhilei; Zhang, Fengming; Wang, Wenjing; Kuznetsov, Andrej Yu; Du, Xiaolong

    2012-05-07

    Nanoscale textured silicon and its passivation are explored by simple low-cost metal-assisted chemical etching and thermal oxidation, and large-area black silicon was fabricated both on single-crystalline Si and multicrystalline Si for solar cell applications. When the Si surface was etched by HF/AgNO(3) solution for 4 or 5 min, nanopores formed in the Si surface, 50-100 nm in diameter and 200-300 nm deep. The nanoscale textured silicon surface turns into an effective medium with a gradually varying refractive index, which leads to the low reflectivity and black appearance of the samples. Mean reflectance was reduced to as low as 2% for crystalline Si and 4% for multicrystalline Si from 300 to 1000 nm, with no antireflective (AR) coating. A black-etched multicrystalline-Si of 156 mm × 156 mm was used to fabricate a primary solar cell with no surface passivation or AR coating. Its conversion efficiency (η) was 11.5%. The cell conversion efficiency was increased greatly by using surface passivation process, which proved very useful in suppressing excess carrier recombination on the nanostructured surface. Finally, a black m-Si cell with efficiency of 15.8% was achieved by using SiO(2) and SiN(X) bilayer passivation structure, indicating that passivation plays a key role in large-scale manufacture of black silicon solar cells. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Research Update: Phonon engineering of nanocrystalline silicon thermoelectrics

    Directory of Open Access Journals (Sweden)

    Junichiro Shiomi

    2016-10-01

    Full Text Available Nanocrystalline silicon thermoelectrics can be a solution to improve the cost-effectiveness of thermoelectric technology from both material and integration viewpoints. While their figure-of-merit is still developing, recent advances in theoretical/numerical calculations, property measurements, and structural synthesis/fabrication have opened up possibilities to develop the materials based on fundamental physics of phonon transport. Here, this is demonstrated by reviewing a series of works on nanocrystalline silicon materials using calculations of multiscale phonon transport, measurements of interfacial heat conduction, and synthesis from nanoparticles. Integration of these approaches allows us to engineer phonon transport to improve the thermoelectric performance by introducing local silicon-oxide structures.

  18. Simulation Research on Micro Contact Based on Force in Silicon Wafer Rotation Grinding

    Science.gov (United States)

    Ren, Qinglei; Wei, Xin; Xie, Xiaozhu; Hu, Wei

    2017-10-01

    Silicon wafer rotation grinding with cup type diamond wheel is a typical ultra precision grinding process. In this paper, a simulation model based on force for micro contact between wheel micro unit and silicon wafer is established from the stable ductile grinding process. Micro contact process in grinding is simulated using the nonlinear explicit finite element analysis software LS-DYNA. The stress-strain results on silicon wafer and wheel micro unit are analyzed by finite element method. The results show that the critical displacement and load corresponding elastic to plastic - plastic to brittle exist on silicon wafer. In silicon plastic zone tangential sliding can produce plastic groove and uplift. Wear of wheel micro unit can be based on the simulation data to judge. The research provides support for wafer grinding and wheel wear mechanism.

  19. Alaska research natural areas: 2. Limestone jags.

    Science.gov (United States)

    G.P. Juday

    1989-01-01

    The 2083-hectare Limestone Jags Research Natural Area in the White Mountains National Recreation Area of central Alaska contains old limestone terrain features––caves, natural bridges, disappearing streams, and cold springs in a subarctic setting. A limestone dissolution joint-type cave in the area is one of the largest reported in high-latitude North America. A...

  20. Research Areas in Adult and Continuing Education

    Science.gov (United States)

    Zawacki-Richter, Olaf; Röbken, Heinke; Ehrenspeck-Kolasa, Yvonne; von Ossietzky, Carl

    2014-01-01

    This study builds upon a Delphi study carried out by Zawacki-Richter (2009) which posited a validated classification of research areas in the special area of distance education. We now replicate the study for the broader field of adult and continuing education (ACE). The aims of this paper are: firstly, to develop a categorisation of research…

  1. Handbook for Social Research in Urban Areas.

    Science.gov (United States)

    Hauser, Philip M.

    Addressed primarily to social scientists and administrators in developing areas, this handbook (a volume in the Technology and Society series) is designed for those not widely experienced in research design and data analysis. Many problem areas of developing nations, such as adequate housing and urban amenities, adjustment and acculturation of…

  2. Tuning Porosity and Surface Area in Mesoporous Silicon for Application in Li-Ion Battery Electrodes.

    Science.gov (United States)

    Cook, John B; Kim, Hyung-Seok; Lin, Terri C; Robbennolt, Shauna; Detsi, Eric; Dunn, Bruce S; Tolbert, Sarah H

    2017-06-07

    This work aims to improve the poor cycle lifetime of silicon-based anodes for Li-ion batteries by tuning microstructural parameters such as pore size, pore volume, and specific surface area in chemically synthesized mesoporous silicon. Here we have specifically produced two different mesoporous silicon samples from the magnesiothermic reduction of ordered mesoporous silica in either argon or forming gas. In situ X-ray diffraction studies indicate that samples made in Ar proceed through a Mg 2 Si intermediate, and this results in samples with larger pores (diameter ≈ 90 nm), modest total porosity (34%), and modest specific surface area (50 m 2 g -1 ). Reduction in forming gas, by contrast, results in direct conversion of silica to silicon, and this produces samples with smaller pores (diameter ≈ 40 nm), higher porosity (41%), and a larger specific surface area (70 m 2 g -1 ). The material with smaller pores outperforms the one with larger pores, delivering a capacity of 1121 mAh g -1 at 10 A g -1 and retains 1292 mAh g -1 at 5 A g -1 after 500 cycles. For comparison, the sample with larger pores delivers a capacity of 731 mAh g -1 at 10 A g -1 and retains 845 mAh g -1 at 5 A g -1 after 500 cycles. The dependence of capacity retention and charge storage kinetics on the nanoscale architecture clearly suggests that these microstructural parameters significantly impact the performance of mesoporous alloy type anodes. Our work is therefore expected to contribute to the design and synthesis of optimal mesoporous architectures for advanced Li-ion battery anodes.

  3. Silicon-on ceramic process: silicon sheet growth and device development for the large-area silicon sheet task of the Low-Cost Solar Array Project. Quarterly report NO. 15, April 1, 1980-June 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, A B; Zook, J D; Grung, B L; McHenry, K; Schuldt, S B; Chapman, P W

    1980-07-31

    The objective of this research is to investigate the technical feasibility of producing solar-cell-quality sheet silicon which could meet the DOE cost goals. The Honeywell approach is to coat one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. Results and accomplishments which occurred during the quarter can be summarized as follows: (1) two major problems associated with SCIM-coating wide (10-cm) substrates were identified and solved; (2) the longitudinal temperature profile in SCIM-II has been improved to prevent substrate warping, buckling, and cracking; (3) the transverse temperature profile in SCIM II has been improved to produce more uniform coatings; (4) a strategy to eliminate effects of thermal stress has been developed; (5) the best SOC cell has a total-area conversion efficiency of 10.5% (AM1, AR), for a cell area of 5 cm/sup 2/; (6) a number of experiments are being investigated for improving cell efficiency; (7) for the slow-cooldown experiment, the average efficiency of 29 AR-coated cells was 9.9%, with a standard deviation of 0.3%; (8) encouraging results were obtained on SOC material that had been treated in a hydrogen plasma at Sandia; and (9) thermal modeling has proven to be beneficial in designing modifications of SCIM II.

  4. REL Pacific Research Alliances and Priority Areas

    Science.gov (United States)

    Regional Educational Laboratory Pacific, 2014

    2014-01-01

    The mission of the Regional Educational Laboratories (RELs) is to help states, districts, and territories use data and research to improve student outcomes. RELs build capacity to do three things: (1) Use data to identify target areas for improvement; (2) Select the best approaches for improvement, drawing on credible and up-to-date research; and…

  5. Green tribology: principles, research areas and challenges.

    Science.gov (United States)

    Nosonovsky, Michael; Bhushan, Bharat

    2010-10-28

    In this introductory paper for the Theme Issue on green tribology, we discuss the concept of green tribology and its relation to other areas of tribology as well as other 'green' disciplines, namely, green engineering and green chemistry. We formulate the 12 principles of green tribology: the minimization of (i) friction and (ii) wear, (iii) the reduction or complete elimination of lubrication, including self-lubrication, (iv) natural and (v) biodegradable lubrication, (vi) using sustainable chemistry and engineering principles, (vii) biomimetic approaches, (viii) surface texturing, (ix) environmental implications of coatings, (x) real-time monitoring, (xi) design for degradation, and (xii) sustainable energy applications. We further define three areas of green tribology: (i) biomimetics for tribological applications, (ii) environment-friendly lubrication, and (iii) the tribology of renewable-energy application. The integration of these areas remains a primary challenge for this novel area of research. We also discuss the challenges of green tribology and future directions of research.

  6. Silicon oxide nanowires: facile and controlled large area fabrication of vertically oriented silicon oxide nanowires for photoluminescence and sensor applications.

    Science.gov (United States)

    Alabi, Taiwo R; Yuan, Dajun; Bucknall, David; Das, Suman

    2013-09-25

    We describe a technique for the fabrication of dense and patterned arrays of aligned silicon oxide nanowires for applications in surface modification, optoelectronic, and electromechanical based devices. Conventional techniques for the fabrication of silicon oxide nanowires based on the vapor-liquid-solid (VLS) chemical vapor deposition (CVD) processes involve the use of high temperatures and catalysts. We demonstrate a technique that extends the use of a plasma thermal reactive ion etching for the fabrication of aligned silicon oxide nanowires with aspect ratios extending up to 20 and lengths exceeding 1 μm. The process incorporates phase separated PS-b-P4VP block copolymer loaded with an iron salt. The iron salt preferentially segregates into the P4VP layer and during an O2 etch is not removed but forms a hexagonally packed array on the silicon oxide substrate. Further etching with CHF3/O2 gas mixture over time can generate nanodots, to nanopillars, and then nanowires of silicon oxide. The photoluminescence property of the as-fabricated nanowire arrays as well as the parasitic ferromagnetic effect from the iron oxide-tipped section of the wires resulting in coalescence under an scanning electron microscope (SEM) are demonstrated. This technique is simpler compared to existing VLS fabrication approaches and can be used for the direct fabrication of patterned arrays of nanowires when a laser interference ablation step is incorporated into the fabrication procedure.

  7. Brazil research in selected scientific areas

    DEFF Research Database (Denmark)

    Ingwersen, Peter

    2009-01-01

      The paper analyses the general development of research in Brazil, 1981-2005 and compares to Mexico, Republic of South Africa (RSA) and the world. Publications from 15 research areas and their citations are analyzed for the three countries covering two five-year periods 1996-2005. The paper...... applies publication growth as well as Citedness and Field Crown Indicators (FCI). Results show that across all research fields, including the Social Sciences, from 1996 the absolute citation impact of Brazil and Mexico are alike, steadily increasing, and just below that of RSA. Publication growth patterns...... for Brazil and Mexico are identical, with a vast increase since 1991. In contrast, RSA follows the global growth rate. From 1996 to 2005 both Latin American countries almost doubles their research publications in English, probably influencing the growth in relative citation impact, as measured by FCI...

  8. Laboratory and test beam results from a large-area silicon drift detector

    CERN Document Server

    Bonvicini, V; Giubellino, P; Gregorio, A; Idzik, M; Kolojvari, A A; Montaño-Zetina, L M; Nouais, D; Petta, C; Rashevsky, A; Randazzo, N; Reito, S; Tosello, F; Vacchi, A; Vinogradov, L I; Zampa, N

    2000-01-01

    A very large-area (6.75*8 cm/sup 2/) silicon drift detector with integrated high-voltage divider has been designed, produced and fully characterised in the laboratory by means of ad hoc designed MOS injection electrodes. The detector is of the "butterfly" type, the sensitive area being subdivided into two regions with a maximum drift length of 3.3 cm. The device was also tested in a pion beam (at the CERN PS) tagged by means of a microstrip detector telescope. Bipolar VLSI front-end cells featuring a noise of 250 e/sup -/ RMS at 0 pF with a slope of 40 e/sup -//pF have been used to read out the signals. The detector showed an excellent stability and featured the expected characteristics. Some preliminary results will be presented. (12 refs).

  9. Amorphous silicon research. Final technical progress report, 1 August 1994--28 February 1998

    Energy Technology Data Exchange (ETDEWEB)

    Guha, S [United Solar Systems Corp., Troy, MI (United States)

    1998-05-01

    This report describes the status and accomplishments of work performed under this subcontract by United Solar Systems. United Solar researchers explored several new deposition regimes/conditions to investigate their effect on material/device performance. To facilitate optimum ion bombardment during growth, a large parameter space involving chamber pressure, rf power, and hydrogen dilution were investigated. United Solar carried out a series of experiments using discharge modulation at various pulsed-plasma intervals to study the effect of Si-particle incorporation on solar cell performance. Hydrogen dilution during deposition is found to improve both the initial and stable performance of a-Si and a-SiGe alloy cells. Researchers conducted a series of temperature-ramping experiments on samples prepared with high and low hydrogen dilutions to study the effect of hydrogen effusion on solar cell performance. Using an internal photoemission method, the electrical bandgap of a microcrystalline p layer used in high-efficiency solar cells was measured to be 1.6 eV. New measurement techniques were developed to evaluate the interface and bulk contributions of losses to solar cell performance. Researchers replaced hydrogen with deuterium and found deuterated amorphous silicon alloy solar cells exhibit reduced light-induced degradation. The incorporation of a microcrystalline n layer in a multijunction cell is seen to improve cell performance. United Solar achieved a world-record single-junction a-Si alloy stable cell efficiency of 9.2% with an active area of 0.25 cm{sup 2} grown with high hydrogen dilution. They also achieved a world-record triple-junction, stable, active-area cell efficiency of 13.0% with an active area of 0.25 cm{sup 2}.

  10. Large-Area Silicon Detectors for the CMS High Granularity Calorimeter

    CERN Document Server

    Pree, Elias

    2017-01-01

    During the so-called Phase-2 Upgrade, the CMS experiment at CERN will undergo significant improvements to cope with the 10-fold luminosity increase of the High Luminosity LHC (HL-LHC) era. Especially the forward calorimetry will suffer from very high radiation levels and intensified pileup in the detectors. For this reason, the CMS collaboration is designing a High Granularity Calorimeter (HGCAL) to replace the existing endcap calorimeters. It features unprecedented transverse and longitudinal segmentation for both electromagnetic (CE-E) and hadronic (CE-H) compartments. The CE-E and a large fraction of CE-H will consist of a sandwich structure with silicon as active detector material. This paper presents an overview of the ongoing sensor development for the HGCAL and highlights important design features and measurement techniques. The design and layout of an 8-inch silicon sensor prototype is shown. The hexagonal sensors consist of 235 pads, each with an area of about \\mbox{1~cm$^{2}$}. Furthermore, Synopsys...

  11. Quantitative analysis of defects in silicon. Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low-Cost Solar Array Project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Natesh, R.; Smith, J.M.; Bruce, T.; Qidwai, H.A.

    1980-04-01

    The complete procedures for the defect analysis of silicon samples using a QTM-720 Image Analyzing System are described, chemical polishing, etching, and QTM operation are discussed. The data from one hundred and seventy four (174) samples, and a discussion of the data are included. The data include twin boundary density, dislocation pit density, and grain boundary length. (WHK)

  12. Simulation-Based Optimization of Cure Cycle of Large Area Compression Molding for LED Silicone Lens

    Directory of Open Access Journals (Sweden)

    Min-Jae Song

    2015-01-01

    Full Text Available Three-dimensional heat transfer-curing simulation was performed for the curing process by introducing a large area compression molding for simultaneous forming and mass production for the lens and encapsulants in the LED molding process. A dynamic cure kinetics model for the silicone resin was adopted and cure model and analysis result were validated and compared through a temperature measurement experiment for cylinder geometry with cure model. The temperature deviation between each lens cavity could be reduced by implementing a simulation model on the large area compression mold and by optimizing the location of heat source. A two-step cure cycle was constructed to reduce excessive reaction peak at the initial stage and cycle time. An optimum cure cycle that could reduce cycle time by more than 29% compared to a one-step cure cycle by adjusting dwell temperature, heating rate, and dwell time was proposed. It was thus confirmed that an optimization of large area LED lens molding process was possible by using the present experiment and the finite element method.

  13. Measurement of LED chips using a large-area silicon photodiode.

    Science.gov (United States)

    Chou, Pei-Ting; Ying, Shang-Ping; Chen, Tzung-Te; Fu, Han-Kuei; Wang, Chien-Ping; Lee, Chih-Kung

    2014-10-10

    We propose the output power measurement of bare-wafer/chip light-emitting diodes (LEDs) using a large-area silicon (Si) photodiode with a simple structure and high accuracy relative to the conventional partial flux measurement using an integrating sphere. To obtain the optical characteristics of the LED chips measured using the two methods, three-dimensional ray-trace simulations are used to perform the measurement deviations owing to the chip position offset or tilt angle. The ray-tracing simulation results demonstrate that the deviation of light remaining in the integrating sphere is approximately 65% for the vertical LED chip and 53% for the flip-chip LED chip if the measurement distance in partial flux method is set to be 5-40 mm. By contrast, the deviation of light hitting the photodiode is only 15% for the vertical LED chip and 23% for the flip-chip LED chip if the large-area Si photodiode is used to measure the output power with the same measurement distance. As a result, the large-area Si photodiode method practically reduces the output power measurement deviations of the bare-wafer/chip LED, so that a high-accuracy measurement can be achieved in the mass production of the bare-wafer/chip LED without the complicated integrating sphere structure.

  14. Development of advanced methods for continuous Czochralski growth. Silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project

    Science.gov (United States)

    Wolfson, R. G.; Sibley, C. B.

    1978-01-01

    The three components required to modify the furnace for batch and continuous recharging with granular silicon were designed. The feasibility of extended growth cycles up to 40 hours long was demonstrated by a recharge simulation experiment; a 6 inch diameter crystal was pulled from a 20 kg charge, remelted, and pulled again for a total of four growth cycles, 59-1/8 inch of body length, and approximately 65 kg of calculated mass.

  15. Prenatal pharmacogenomics: a promising area for research.

    Science.gov (United States)

    Dorfman, E H; Cheng, E Y; Hebert, M F; Thummel, K E; Burke, W

    2016-08-01

    Clinical applications of prenatal genetic screening currently focus on detection of aneuploidy and other genetic diseases in the developing fetus. Growing evidence suggests that the fetal genome may also be informative about fetal exposures through contributions to placental transport as well as placental and fetal metabolism. Possible clinical applications of prenatal pharmacogenomic screening include prospective optimization of medication selection and dosage, as well as retrospective assessment of whether a fetus was previously exposed to significant risk. Newly available noninvasive methods of prenatal genetic screening mean that relevant fetal genotypes could be made available to obstetricians for use in management of a current pregnancy. This promising area for research merits more attention than it has thus far received.The Pharmacogenomics Journal advance online publication, 10 May 2016; doi:10.1038/tpj.2016.33.

  16. Gamma Large Area Silicon Telescope (GLAST): Applying silicon strip detector technology to the detection of gamma rays in space

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, W.B.; The GLAST Collaboration

    1993-06-01

    The recent discoveries and excitement generated by space satellite experiment EGRET (presently operating on Compton Gamma Ray Observatory -- CGRO) have prompted an investigation into modern detector technologies for the next generation space based gamma ray telescopes. The GLAST proposal is based on silicon strip detectors as the {open_quotes}technology of choice{close_quotes} for space application: no consumables, no gas volume, robust (versus fragile), long lived, and self triggerable. The GLAST detector basically has two components: a tracking module preceding a calorimeter. The tracking module has planes of crossed strip (x,y) 300 {mu}m pitch silicon detectors coupled to a thin radiator to measure the coordinates of converted electron-positron pairs. The gap between the layers ({approximately}5 cm) provides a lever arm for track fitting resulting in an angular resolution of <0.1{degree} at high energy. The status of this R & D effort is discussed including details on triggering the instrument, the organization of the detector electronics and readout, and work on computer simulations to model this instrument.

  17. Large-Area, UV-Optimized, Back-Illuminated Silicon Photomultiplier Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Existing photocathode-based technologies for visible and UV instruments lack sensitivity, are bulky, and have limited reliability. Solid-state silicon...

  18. Dip coating process. Silicon sheet growth development for the large-area silicon sheet task of the Low Cost Silicon Solar Array Project. Quarterly report No. 5, December 18, 1976--March 21, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Zook, J.D.; Heaps, J.D.; Maciolek, R.B.; Koepke, B.; Butter, C.D.; Schuldt, S.B.

    1977-03-31

    Ceramic substrates can be coated with a thin layer of large-grain polycrystalline silicon by a dip-coating process. The silicon-on-ceramic (SOC) material appears to be quite promising as a low-cost cell material but requires somewhat special fabrication procedure since the contacts to both the n- and p-layers are now made on the front surface. Solar cells have been made on SOC material and on single-crystal control samples. Photodiodes 0.01 to 0.1 cm/sup 2/ made on substrates coated with vitreous carbon prior to dip coating with silicon showed the best efficiency of SOC material to date, namely over 6 percent uncorrected and about 12 percent inherent efficiency. Etching procedures have indicated that the dislocation density varies from almost 10/sup 7/ cm/sup -2/ to almost dislocation-free material, assuming that all etch pits are due to dislocations. EBIC measurements procedures were also improved, and it was found that diodes appear to be fairly uniform in EBIC response. A new SOC coating facility is being designed which will coat larger substrates in a continuous manner. The purpose is to minimize the contamination problem by reducing the contact area of the substrate with molten silicon. By having much larger throughput, it will also demonstrate the scale-up potential of the silicon-on-ceramic process. Portions of the new facility are under construction. An attempt has been made to model the economics of a large-scale facility for coating ceramic panels with silicon. A first iteration based on available parameters estimates showed that major cost items were poly Si ($2.90 per square meter), labor and burden ($2.50 per square meter), and the ceramic substrate ($2.50 per square meter), for a total price of about $11 per square meter.

  19. Silicon Valley Meets Biomedical Research in the Chan Zuckerberg Initiative.

    Science.gov (United States)

    Crow, Diana

    2017-05-18

    The Chan Zuckerberg Initiative, the philanthropy launched by Facebook CEO Mark Zuckerberg and his wife Priscilla Chan, drew attention with its stated goal of helping to "cure, manage, or treat all diseases" by the end of the century. They intend to do it through funding basic research and addressing gaps in biomedical technology. Copyright © 2017. Published by Elsevier Inc.

  20. Application of CBD-Zinc Sulfide Film as an Antireflection Coating on Very Large Area Multicrystalline Silicon Solar Cell

    Directory of Open Access Journals (Sweden)

    J. Yi

    2008-03-01

    Full Text Available The low-cost chemical bath deposition (CBD technique is used to prepare CBD-ZnS films as antireflective (AR coating for multicrystalline silicon solar cells. The uniformity of CBD-ZnS film on large area of textured multicrystalline silicon surface is the major challenge of CBD technique. In the present work, attempts have been made for the first time to improve the rate of deposition and uniformity of deposited film by controlling film stoichiometry and refractive index and also to minimize reflection loss by proper optimization of molar percentage of different chemical constituents and deposition conditions. Reasonable values of film deposition rate (12.13 Å′/min., good film uniformity (standard deviation <1, and refractive index (2.35 along with a low percentage of average reflection (6-7% on a textured mc-Si surface are achieved with proper optimization of ZnS bath. 12.24% efficiency on large area (125 mm × 125 mm multicrystalline silicon solar cells with CBD-ZnS antireflection coating has been successfully fabricated. The viability of low-cost CBD-ZnS antireflection coating on large area multicrystalline silicon solar cell in the industrial production level is emphasized.

  1. Time-Efficient High-Resolution Large-Area Nano-Patterning of Silicon Dioxide

    DEFF Research Database (Denmark)

    Lin, Li; Ou, Yiyu; Aagesen, Martin

    2017-01-01

    A nano-patterning approach on silicon dioxide (SiO2) material, which could be used for the selective growth of III-V nanowires in photovoltaic applications, is demonstrated. In this process, a silicon (Si) stamp with nanopillar structures was first fabricated using electron-beam lithography (EBL...

  2. Street racing: a neglected research area?

    Science.gov (United States)

    Vingilis, Evelyn; Smart, Reginald G

    2009-04-01

    To review: (1) the extent and frequency of street racing and its consequences; (2) the characteristics of street racers; (3) explanatory theories for street racing; (4) the legal issues; and (5) the best methods of preventing street racing. Review of academic and other literature. Very limited official statistics are available on street racing offenses and related collisions, in part because of the different jurisdictional operational definitions of street racing and the ability of police to determine whether street racing was a contributing factor. Some data on prevalence of street racing have been captured through social surveys and they found that between 18.8 and 69.0 percent of young male drivers from various international jurisdictions have reported street racing. Moreover, street racing is found to be associated with other risky behaviors, substance abuse, and delinquent activities. The limited evidence available on street racing suggests that it has increased in the last decade. Street racing is a neglected research area and the time has come to examine the prevalence and causes of street racing and the effectiveness of various street racing countermeasures.

  3. Research on stable, high-efficiency amorphous silicon multijunction modules. Final subcontract report, 1 January 1991--31 August 1994

    Energy Technology Data Exchange (ETDEWEB)

    Guha, S. [United Solar Systems Corp., Troy, MI (United States)

    1994-10-01

    The principal objective of this program is to conduct research on semiconductor materials and non-semiconductor materials to enhance the performance of multibandgap, multijunction, large-area amorphous silicon-based alloy modules. The goal for this program is to demonstrate stabilized module efficiency of 12% for multijunction modules of area greater than 900 cm{sup 2}. Double-junction and triple-junction cells are made on Ag/ZnO back reflector deposited on stainless steel substrates. The top cell uses a-Si alloy; a-SiGe alloy is used for the i layer in the middle and the bottom cells. After evaporation of antireflection coating, silver grids and bus bars are put on the top surface, and the panel is encapsulated in an ethylene vinyl acetate (EVA)/Tefzel structure to make a one-square-foot monolithic module.

  4. Diaphragm metering pumps for cooling silicon sensors at the CERN research center for particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Geiselhart, Marc [LEWA Pumpen AG, Reinach (Switzerland); CERN Press Office, Geneva (Switzerland)

    2016-12-15

    With approximately 9,600 magnets and a circumference of 26.659 km, the Large Hadron Collider (LHC) is the largest and most sophisticated accelerator operated by the CERN research institute. The Large Hadron Collider beauty (LHCb) experiment, the A Toroidal LHC ApparatuS (ATLAS) experiment, and the Compact Muon Solenoid (CMS) experiment are three of the four experiments currently installed at LHC. In order to achieve precise measurements, silicon detectors are built in close vicinity to the interaction point of all experiments. Carbon dioxide cooling plants cool the innermost layers of the silicon detectors down to temperatures as low as -40 C. Two diaphragm metering pumps have been used for the LHCb experiment since 2007. Two similar systems operated in redundancy guarantee from the beginning of 2015 the thermal management of the IBL sub-detector of the TALS experiment.

  5. Clinical Epidemiology Unit - overview of research areas

    Science.gov (United States)

    Clinical Epidemiology Unit (CEU) conducts etiologic research with potential clinical and public health applications, and leads studies evaluating population-based early detection and cancer prevention strategies

  6. Research Areas in Distance Education: A Delphi Study

    Directory of Open Access Journals (Sweden)

    Olaf Zawacki-Richter

    2009-06-01

    Full Text Available This study had three purposes: Firstly, to develop a categorization of research areas in distance education; secondly, to identify the most important research areas in distance education; and thirdly, to identify the most neglected research areas in distance education. Based on a literature review and a Delphi study, three broad levels or perspectives with 15 research areas were derived to organize the body of knowledge in distance education. Prospective researchers can use the results to identify gaps and priority areas and to explore potential research directions.

  7. Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment.

    Science.gov (United States)

    Liu, Neng; Moumanis, Khalid; Dubowski, Jan J

    2015-11-09

    The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of biosensing devices. We report on a protocol of using KrF and ArF lasers irradiating Si (001) samples immersed in a liquid environment with low number of pulses and operating at moderately low pulse fluences to induce Si wettability modification. Wafers immersed for up to 4 hr in a 0.01% H2O2/H2O solution did not show measurable change in their initial contact angle (CA) ~75°. However, the 500-pulse KrF and ArF lasers irradiation of such wafers in a microchamber filled with 0.01% H2O2/H2O solution at 250 and 65 mJ/cm(2), respectively, has decreased the CA to near 15°, indicating the formation of a superhydrophilic surface. The formation of OH-terminated Si (001), with no measurable change of the wafer's surface morphology, has been confirmed by X-ray photoelectron spectroscopy and atomic force microscopy measurements. The selective area irradiated samples were then immersed in a biotin-conjugated fluorescein-stained nanospheres solution for 2 hr, resulting in a successful immobilization of the nanospheres in the non-irradiated area. This illustrates the potential of the method for selective area biofunctionalization and fabrication of advanced Si-based biosensing architectures. We also describe a similar protocol of irradiation of wafers immersed in methanol (CH3OH) using ArF laser operating at pulse fluence of 65 mJ/cm(2) and in situ formation of a strongly hydrophobic surface of Si (001) with the CA of 103°. The XPS results indicate ArF laser induced formation of Si-(OCH3)x compounds responsible for the observed hydrophobicity. However, no such compounds were found by XPS on the Si surface irradiated by KrF laser in methanol, demonstrating the inability of the KrF laser to photodissociate methanol and create -OCH3 radicals.

  8. Research Areas in Distance Education: A Delphi Study

    Science.gov (United States)

    Zawacki-Richter, Olaf

    2009-01-01

    This study had three purposes: Firstly, to develop a categorization of research areas in distance education; secondly, to identify the most important research areas in distance education; and thirdly, to identify the most neglected research areas in distance education. Based on a literature review and a Delphi study, three broad levels or…

  9. Lithographically patterned silicon nanostructures on silicon substrates

    Energy Technology Data Exchange (ETDEWEB)

    Megouda, Nacera [Institut de Recherche Interdisciplinaire (IRI, USR 3078), Universite Lille1, Parc de la Haute Borne, 50 Avenue de Halley-BP 70478, 59658 Villeneuve d' Ascq and Institut d' Electronique, de Microelectronique et de Nanotechnologie (IEMN, CNRS-8520), Cite Scientifique, Avenue Poincare-B.P. 60069, 59652 Villeneuve d' Ascq (France); Faculte des Sciences, Universite Mouloud Mammeri, Tizi-Ouzou (Algeria); Unite de Developpement de la Technologie du Silicium (UDTS), 2 Bd. Frantz Fanon, B.P. 140 Alger-7 merveilles, Alger (Algeria); Piret, Gaeelle; Galopin, Elisabeth; Coffinier, Yannick [Institut de Recherche Interdisciplinaire (IRI, USR 3078), Universite Lille1, Parc de la Haute Borne, 50 Avenue de Halley-BP 70478, 59658 Villeneuve d' Ascq and Institut d' Electronique, de Microelectronique et de Nanotechnologie (IEMN, CNRS-8520), Cite Scientifique, Avenue Poincare-B.P. 60069, 59652 Villeneuve d' Ascq (France); Hadjersi, Toufik, E-mail: hadjersi@yahoo.com [Unite de Developpement de la Technologie du Silicium (UDTS), 2 Bd. Frantz Fanon, B.P. 140 Alger-7 merveilles, Alger (Algeria); Elkechai, Omar [Faculte des Sciences, Universite Mouloud Mammeri, Tizi-Ouzou (Algeria); and others

    2012-06-01

    The paper reports on controlled formation of silicon nanostructures patterns by the combination of optical lithography and metal-assisted chemical dissolution of crystalline silicon. First, a 20 nm-thick gold film was deposited onto hydrogen-terminated silicon substrate by thermal evaporation. Gold patterns (50 {mu}m Multiplication-Sign 50 {mu}m spaced by 20 {mu}m) were transferred onto the silicon wafer by means of photolithography. The etching process of crystalline silicon in HF/AgNO{sub 3} aqueous solution was studied as a function of the silicon resistivity, etching time and temperature. Controlled formation of silicon nanowire arrays in the unprotected areas was demonstrated for highly resistive silicon substrate, while silicon etching was observed on both gold protected and unprotected areas for moderately doped silicon. The resulting layers were characterized using scanning electron microscopy (SEM).

  10. Coconut Program Area Research Planning and Prioritization

    OpenAIRE

    Aragon, Corazon

    2000-01-01

    The coconut industry is one of the country's major pillars in employment generation and foreign exchange earnings. However, local production problems, the expansion in coconut hectarage of neighboring countries, and recent developments in biotechnology research on other competing crops that have high lauric oil content might affect its long-term sustainability and viability. In a highly liberalized global trade environment, innovation and creativity in the country's coconut industry are neede...

  11. Large-area Silicon-Film{trademark} panels and solar cells. Final technical report, July 1995--March 1998

    Energy Technology Data Exchange (ETDEWEB)

    Rand, J.A.; Bai, Y.; Barnett, A.M.; Culik, J.S.; Ford, D.H.; Hall, R.B.; Kendall, C.L. [AstroPower, Inc., Newark, DE (US)

    1998-09-01

    This report will detail substantial improvements in each of the task areas. A number of new products were developed, including a 130 kW array built using a new panel design. Improvements in laboratory-scale solar cell processing resulted in a confirmed efficiency of 16.6%. A new Silicon-Film{trademark} production sheet machine was built which increased throughput by 70%. Three solar cell fabrication processes were converted from low throughout batch processes to high throughput, continuous, belt processes. These new processes are capable of processing sheet over 31 cm in width. Finally, a new Silicon-Film{trademark} sheet machine was built that demonstrated a sheet width of 38 cm. This tool enabled AstroPower to demonstrate a wide range of solar cell sizes, many of which have generated considerable market interest.

  12. Light management in large area thin-film silicon solar modules

    Czech Academy of Sciences Publication Activity Database

    Losio, P.A.; Caglar, O.; Cashmore, J.S.; Hötzel, J.E.; Ristau, S.; Holovský, Jakub; Remeš, Zdeněk; Sinicco, I.

    2015-01-01

    Roč. 143, Dec (2015), s. 375-385 ISSN 0927-0248 R&D Projects: GA ČR(CZ) GA14-05053S Institutional support: RVO:68378271 Keywords : micromorph * thin-film silicon solar cells * light management * ZnO Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.732, year: 2015

  13. Simple processing of back-contacted silicon heterojunction solar cells using selective-area crystalline growth

    KAUST Repository

    Tomasi, Andrea

    2017-04-24

    For crystalline-silicon solar cells, voltages close to the theoretical limit are nowadays readily achievable when using passivating contacts. Conversely, maximal current generation requires the integration of the electron and hole contacts at the back of the solar cell to liberate its front from any shadowing loss. Recently, the world-record efficiency for crystalline-silicon single-junction solar cells was achieved by merging these two approaches in a single device; however, the complexity of fabricating this class of devices raises concerns about their commercial potential. Here we show a contacting method that substantially simplifies the architecture and fabrication of back-contacted silicon solar cells. We exploit the surface-dependent growth of silicon thin films, deposited by plasma processes, to eliminate the patterning of one of the doped carrier-collecting layers. Then, using only one alignment step for electrode definition, we fabricate a proof-of-concept 9-cm2 tunnel-interdigitated back-contact solar cell with a certified conversion efficiency >22.5%.

  14. Silicon photonic switch technology for optical networks in telecom and datacom areas

    Science.gov (United States)

    Nakamura, Shigeru; Yanagimachi, Shigeyuki; Takeshita, Hitoshi; Tajima, Akio

    2017-01-01

    As a promising platform technology for optical switches, silicon photonics is recently attracting much attention. In this paper, we demonstrate compact 8 × 8 silicon photonic switch modules with low loss, low polarization sensitivity, and low cross-talk properties. An optical circuit including 152 thermo-optical switch elements and spot size converters were formed within a silicon chip size of 12 mm × 14 mm. The developed module where a silicon photonic chip was assembled with a fiber array showed about 6-dB average excess optical loss, including optical coupling loss, on all 64 paths of the 8 × 8 optical switch. Measured polarization dependent loss was about 0.6 dB on average over 64 paths and cross-talk was less than -35 dB. These optical switch modules are intended for applying to ROADMs in telecom optical networks, but, the port count extensibility using multiple compact modules and the faster switching capability of the optical switch are also useful for datacenter applications where hybrid network scheme with electronic packet switches and optical circuit switches is intensively investigated.

  15. Small UAS Test Area at NASA's Dryden Flight Research Center

    Science.gov (United States)

    Bauer, Jeffrey T.

    2008-01-01

    This viewgraph presentation reviews the areas that Dryden Flight Research Center has set up for testing small Unmanned Aerial Systems (UAS). It also reviews the requirements and process to use an area for UAS test.

  16. Floating Substrate Process. Large-Area Silicon Sheet Task, Low-Cost Solar Array Project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garfinkel, M.; Hall, R.N.

    1978-06-23

    The work described was directed toward the demonstration of the practical feasibility of the Floating Substrate Process for the growth of silicon sheet. Supercooling of silicon--tin alloy melts was studied. Values as high as 78/sup 0/C at 1100/sup 0/C and 39/sup 0/C at 1200/sup 0/C were observed, corresponding to supersaturation parameter values 0.025 and 0.053 at 1050/sup 0/C and 1150/sup 0/C, respectively. The interaction of tin with silane gas streams was investigated over the temperature range 1000 to 1200/sup 0/C. Single-pass conversion efficiencies exceeding 30% were obtained. The growth habit of spontaneously-nucleated surface growth was determined to be consistent with dendritic and web growth from <111> singly-twinned triangular nucleii. Surface growth of interlocking silicon crystals, thin enough to follow the surface of the liquid and with growth velocity as high as 5 mm/min, was obtained. Large area single-crystal growth along the melt surface was not achieved. Small single-crystal surface growth was obtained which did not propagate beyond a few millimeters. The probable reason for the polycrystalline growth is the poisoning of the growth interface by impurities.

  17. Market Research: An Area in Need of Nurse Researchers.

    Science.gov (United States)

    Froberg, Debra G.; And Others

    1986-01-01

    The application of marketing principles to nursing education and the need for research into the applicant market are discussed for nursing education programs, effective recruiting techniques, prediction of student success in nursing education, program quality, and the current and future nursing market. (Author/MSE)

  18. Plasma texturing on large-area industrial grade CZ silicon solar cells

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Nordseth, Ørnulf; Boisen, Anja

    2013-01-01

    -mono-crystalline Si. The process was successfully integrated in fabrication of solar cells using only industry standard processes on a Czochralski (CZ) silicon starting material. The resulting cell performance was compared to cells with conventional texturing. For cells, where the nanostructuring was not fully......We report on an experimental study of nanostructuring of silicon solar cells using reactive ion etching (RIE). A simple mask-less, scalable RIE nanostructuring of the solar cell surface is shown to reduce the AM1.5-weighted average reflectance to a level below 1 % in a fully optimized RIE texturing......, and thus holds a significant potential for improvement of the cell performance compared to current industrial standards. The reflectance is shown to remain below that of conventional textured cells also at high angle of incidence. The process is shown to be equally applicable to mono-, multi- and quasi...

  19. Large-area Silicon-Film{trademark} panels and solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Rand, J.A.; Barnett, A.M.; Checchi, J.C. [AstroPower, Inc., Newark, DE (United States)] [and others

    1997-01-01

    This report describes AstroPower`s success in improving its material and processing capabilities during the first phase of this 3-year contract through the Photovoltaic Manufacturing Technology (PVMaT) program. Key results include the demonstration of a 14.6%-efficient Silicon-Film{trademark} solar cell. This laboratory result (1.0 cm{sup 2}) provides the direction needed to develop and optimize continuous, in-line production processes. The continuous nature of the Silicon-Film{trademark} sheet fabrication process is being extended into the solar-cell processing sequence. Plans are in place to make the wafer cleaning, gettering, and diffusion steps all continuous during the scope of this program.

  20. Optimization of sodium carbonate texturization on large-area crystalline silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Marrero, N.; Gonzalez-Diaz, B.; Guerrero-Lemus, R.; Hernandez-Rodriguez, C. [Departamento de Fisica Basica, Universidad de La Laguna, Avda, Astrofisico Francisco Sanchez, 38204 La Laguna, S/C de Tenerife (Spain); Borchert, D. [Auf der Reihe 2, Institut fuer Solare Energiesysteme, Fraunhofer Institut, 45884 Gelsenkirchen (Germany)

    2007-12-14

    This work describes a texturization method for monocrystalline silicon solar cells based on a mixture of sodium carbonate and sodium hydrogen carbonate solutions. A specific solution has been found that results in an optimal etching rate, the lowest surface reflectance and a homogeneous density of pyramidal structures on the silicon surface. The subsequent phosphorus diffusion with rapid thermal processes has been modified in order to drastically reduce the process time and, simultaneously, to obtain a high homogeneity of the sheet resistance values and improved photocarriers lifetimes. 100 x 100 mm solar cells with an efficiency of 15.8% have been obtained compared to an efficiency of 14.7% for the reference cell. (author)

  1. Influence of stain etching on low minority carrier lifetime areas of multicrystalline silicon for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Montesdeoca-Santana, A. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Fraunhofer Institute for Solar Energy Systems, Laboratory and Servicecenter Gelsenkirchen, Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Gonzalez-Diaz, B. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Departamento de Energia Fotovoltaica, Instituto Tecnologico y de Energias Renovables. Poligono Industrial de Granadilla s/n, 38600 San Isidro-Granadilla de Abona (Spain); Jimenez-Rodriguez, E. [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Ziegler, J. [Fraunhofer Institute for Solar Energy Systems, Laboratory- and Servicecenter Gelsenkirchen. Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Velazquez, J.J. [Departamento de Fisica Fundamental y Experimental, Electronica y Sistemas, Universidad de La Laguna. Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain); Hohage, S.; Borchert, D. [Fraunhofer Institute for Solar Energy Systems, Laboratory and Servicecenter Gelsenkirchen. Auf der Reihe 2, 45884 Gelsenkirchen (Germany); Guerrero-Lemus, R., E-mail: rglemus@ull.es [Departamento de Fisica Basica, Universidad de La Laguna, Avda. Astrofisico Francisco Sanchez, 38206 La Laguna (Spain)

    2011-11-15

    Highlights: > An enhanced minority carrier lifetime at extended defects in multicrystalline silicon is observed with the use of HF/HNO{sub 3} stain etching to texture the surface. > FTIR analysis shows no influence of oxide passivation in this effect. > SEM images show a preferential etching at extended defects suggesting smoothing at defects as one of the causes for the reduced recombination activity. > LBIC images show a reduction in IQE at extended defects in HF/HNO{sub 3} textured multicrystalline solar cells. - Abstract: In this work the use of HF/HNO{sub 3} solutions for texturing silicon-based solar cell substrates by stain etching and the influence of texturing on minority carrier lifetimes are studied. Stain etching is currently used to decrease the reflectance and, subsequently improve the photogenerated current of the cells, but also produces nanostructures on the silicon surface. In the textured samples it has been observed that an improvement on the minority carrier lifetime with respect to the samples treated with a conventional saw damage etching process is produced on grain boundaries and defects, and the origin of this effect has been discussed.

  2. Measurement of the nTOF beam profile in the second experimental area (EAR2) using a silicon detector

    CERN Document Server

    Suljik, Fidan

    2017-01-01

    A new beam line and a second experimental area (EAR2) have been recently built at the neutron Time-Of-Flight (nTOF) facility at CERN. The characterization of the neutron beam in terms of spatial profile is a prerequisite for high accuracy cross-sections measurements. A silicon strip detector equipped with a neutron converter has been used to determine the beam profile as a function of incident neutron energy, in particular neutron beam profile has been measured from thermal energy up to 10 eV. Preliminary results have been compared with those collected with a MicroMegas detector also installed during the measurement.

  3. A New Area in Main-Group Chemistry: Zerovalent Monoatomic Silicon Compounds and Their Analogues.

    Science.gov (United States)

    Yao, Shenglai; Xiong, Yun; Driess, Matthias

    2017-08-15

    Monoatomic zerovalent main-group element complexes emerged very recently and attracted increasing attention of both theoretical and experimental chemists. In particular, zerovalent silicon complexes and their congeners (metallylones) stabilized by neutral Lewis donors are of significant importance not only because of their intriguing electronic structure but also because they can serve as useful building blocks for novel chemical species. Featuring four valence electrons as two lone pairs at the central atoms, such complexes may form donor-acceptor adducts with Lewis acids. More interestingly, with the central atoms in the oxidation state of zero, they could pave a way to new classes of compounds and functional groups that are otherwise difficult to realize. In this Account, we mainly describe our contributions in the chemistry of monatomic zerovalent silicon (silylone) and germanium (germylone) supported by a chelate bis-N-heterocyclic carbene (bis-NHC) ligand in the context of related species developed by other groups in the meantime. Utilizing the bis-NHC stabilized chlorosilyliumylidene [:SiCl]+ and chlorogermyliumylidene [:GeCl]+ as suitable starting materials, we successfully isolated silylone (bis-NHC)Si and germylone (bis-NHC)Ge, respectively. The electronic structures of the latter complexes established by theoretical calculations and spectroscopic data revealed that they are genuine metallylone species with electron-rich silicon(0) and germanium(0) centers. Accordingly, they can react with 1 molar equiv of GaCl3 to form Lewis adducts (bis-NHC)E(GaCl3) (E = Si, Ge) and with 2 molar equiv of ZnCl2 to furnish (bis-NHC)Si(ZnCl2)2. Conversion of the metallylones with elemental chalcogens affords isolable monomeric silicon(II) and germanium(II) monochalcogenides (bis-NHC)EX(GaCl3) (X = Se, Te), representing molecular heavier congeners of CO. Moreover, their reaction with elemental chalcogens can also yield monomeric silicon(IV) and germanium(IV) dichalcogenides

  4. Research Opportunities in Crystalline Silicon Photovoltaics for the 21st Century

    Energy Technology Data Exchange (ETDEWEB)

    Atwater, Harry A.; Ciszek, Ted; Feldman, Leonard C.; Gee, James; Rohatgi, Ajeet; Sopori, Bhushan

    1999-07-28

    Crystalline silicon continues to be the dominant semiconductor material used for terrestrial photovoltaics. This paper discusses the scientific issues associated with silicon photovoltaics processing, and cell design that may yield cell and module performance improvements that are both evolutionary and revolutionary in nature. We first survey critical issues in ''thick'' crystalline silicon photovoltaics, including novel separations processes for impurity removal, impurity and defect fundamentals, interface passivation, the role of hydrogen. Second, we outline emerging opportunities for creation of a very different ''thin-layer'' silicon cell structure, including the scientific issues and engineering challenges associated with thin-layer silicon processing and cell design.

  5. The Centre for Food Innovation -- Research Areas and Potential Projects

    Science.gov (United States)

    2013-04-01

    milk powder, UHT milk , cheese, butter and margarine  seafood (oysters, live lobster, live abalone, live king crab)  fresh fruit (citrus)  wheat...research areas – mid to long term (5-20 years) Research Area/project Market pull/push Support Technologies Dairy - milk , cheese, yoghurt, protein

  6. Cherry Creek Research Natural Area: guidebook supplement 41

    Science.gov (United States)

    Reid Schuller; Jennie Sperling; Tim. Rodenkirk

    2011-01-01

    This guidebook describes Cherry Creek Research Natural Area, a 239-ha (590-ac) area that supports old-growth Douglas-fir-western hemlock (Pseudotsuga menziesii- Tsuga heterophylla) forest occurring on sedimentary materials in the southern Oregon Coast Range. Major plant associations present within the area include the western hemlock/Oregon oxalis...

  7. Research on the basic understanding of high efficiency in silicon solar cells. Annual report, 1 December 1982-30 November 1983

    Energy Technology Data Exchange (ETDEWEB)

    Rohatgi, A.; Rai-Choudhury, P.

    1984-09-01

    This report presents results of research designed to develop a basic understanding of high-efficiency silicon solar cells and achieve cell efficiencies greater than 17% by employing innovative concepts of material preparation, cell design, and fabrication technology. The research program consisted of a theoretical effort to develop models for very high-efficiency cell designs, experimental verification of the designs, and improved understanding of efficiency-limiting mechanisms such as heavy doping effects and bulk and surface recombination. Research was performed on high-lifetime float-zone silicon, the baseline materials, low-resistivity gallium-doped czochralski silicon, and boron-doped float-zone silicon.

  8. Hybrid Si nanowire/amorphous silicon FETs for large-area image sensor arrays.

    Science.gov (United States)

    Wong, William S; Raychaudhuri, Sourobh; Lujan, René; Sambandan, Sanjiv; Street, Robert A

    2011-06-08

    Silicon nanowire (SiNW) field-effect transistors (FETs) were fabricated from nanowire mats mechanically transferred from a donor growth wafer. Top- and bottom-gate FET structures were fabricated using a doped a-Si:H thin film as the source/drain (s/d) contact. With a graded doping profile for the a-Si:H s/d contacts, the off-current for the hybrid nanowire/thin-film devices was found to decrease by 3 orders of magnitude. Devices with the graded contacts had on/off ratios of ∼10(5), field-effect mobility of ∼50 cm(2)/(V s), and subthreshold swing of 2.5 V/decade. A 2 in. diagonal 160 × 180 pixel image sensor array was fabricated by integrating the SiNW backplane with an a-Si:H p-i-n photodiode.

  9. LASSA: a large area silicon strip array for isotopic identification of charged particles

    Science.gov (United States)

    Davin, B.; de Souza, R. T.; Yanez, R.; Larochelle, Y.; Alfaro, R.; Xu, H. S.; Alexander, A.; Bastin, K.; Beaulieu, L.; Dorsett, J.; Fleener, G.; Gelovani, L.; Lefort, T.; Poehlman, J.; Charity, R. J.; Sobotka, L. G.; Elson, J.; Wagner, A.; Liu, T. X.; Liu, X. D.; Lynch, W. G.; Morris, L.; Shomin, R.; Tan, W. P.; Tsang, M. B.; Verde, G.; Yurkon, J.

    2001-11-01

    A new high resolution, charged particle detector array, LASSA, has been developed. LASSA consists of nine individual telescopes that each utilizes a Si-Si-CsI(Tl) stack to provide isotopic identification of fragments /(1<=Z<=8) with good angular resolution over a wide dynamic range in energy. The energy range covered is /E/A=2.4-140MeV for protons and /E/A=4.8-335MeV for 16O ions. The front portion of each telescope is comprised of a 65μm Si(IP) strip detector backed by a 500μm Si(IP) strip detector. This second detector provides position information in two dimensions. Behind the second silicon detector is a cluster of four 6 cm thick CsI(Tl) crystals, each read-out by a photodiode. The design, construction, and performance characteristics of this detector telescope are described.

  10. LASSA: a large area silicon strip array for isotopic identification of charged particles

    Energy Technology Data Exchange (ETDEWEB)

    Davin, B.; Souza, R.T. de E-mail: desouza@indiana.edu; Yanez, R.; Larochelle, Y.; Alfaro, R.; Xu, H.S.; Alexander, A.; Bastin, K.; Beaulieu, L.; Dorsett, J.; Fleener, G.; Gelovani, L.; Lefort, T.; Poehlman, J.; Charity, R.J.; Sobotka, L.G.; Elson, J.; Wagner, A.; Liu, T.X.; Liu, X.D.; Lynch, W.G.; Morris, L.; Shomin, R.; Tan, W.P.; Tsang, M.B.; Verde, G.; Yurkon, J

    2001-11-11

    A new high resolution, charged particle detector array, LASSA, has been developed. LASSA consists of nine individual telescopes that each utilizes a Si-Si-CsI(Tl) stack to provide isotopic identification of fragments (1{<=}Z{<=}8) with good angular resolution over a wide dynamic range in energy. The energy range covered is E/A=2.4-140 MeV for protons and E/A=4.8-335 MeV for {sup 16}O ions. The front portion of each telescope is comprised of a 65 {mu}m Si(IP) strip detector backed by a 500 {mu}m Si(IP) strip detector. This second detector provides position information in two dimensions. Behind the second silicon detector is a cluster of four 6 cm thick CsI(Tl) crystals, each read-out by a photodiode. The design, construction, and performance characteristics of this detector telescope are described.

  11. Families in Later Life: A Burgeoning Research Area.

    Science.gov (United States)

    Brubaker, Timothy H.

    1990-01-01

    Reviews research from 1980s focusing on families who are beyond child-rearing years. Sees later-life families as characterized by continuity and changes as they experience marriage, divorce, widowhood, remarriage, childlessness, grandparenthood, sibling relationships, and family caregiving. Suggests areas for future research focusing on…

  12. Report for fiscal 1998 on results of research and development of silicon-based polymeric material. Material research for the liquid methane fueled aircraft engine; 1998 nendo keisokei kobunshi zairyo no kenkyu kaihatsu seika hokokusho. Methane nenryo kokukiyo engine kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Research was conducted for the purpose of establishing basic technology concerning molecular design, synthesis, material formation, and evaluation of silicon-based polymers which are expected to provide superior electronic/optical functions, high heat/combustion resistance and dynamic properties. The research subjects were such as following: research and development of silicon-based polymeric materials with sea-island microstructures; research and development of silicon-based polymeric materials with sea-island microstructures; research and development on IPN formation with silicon-based polymers; research and development of hybrid silicon polymers with organometallic compounds; research and development of silicon containing polymer materials with ring structures; general committee for investigation and research; the optimized low-temperature Wurtz synthesis and modification of polysilanes; study of unsaturated and hypercoordinate organosilicon compounds; basic studies on the synthesis and properties of silicon-based high polymers; studies of new monomer-synthesis and their polymerization reaction; studies on new method of preparation and functionalization of polysilanes; novel applications of silicon-based polymers in imaging devices for information display, memory, and recordings; and molecular design of silicon-containing {pi}-conjugated and {sigma}-conjugated compounds. (NEDO)

  13. Large area silicon sheet by EFG. Fourth quarterly report, October 1, 1977--December 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Wald, F.V.

    1978-01-15

    A detailed economic evaluation is presented of several EFG ribbon growth technology scenarios using the ''SAMICS'' interim price estimation guidelines. It is concluded that the growth of 10 ribbons from a double five ribbon furnace of the general type represented by the existing Machine 3A would meet the requirements of producing ribbon at a price below $20/m/sup 2/ the 1986 goal. The technology requirements are that one operator can operate 2 of the 5 ribbon growth stations in which each ribbon grows at a speed of 7.5 cm/min and is also 7.5 cm wide. The machines also would have to achieve a duty cycle of 67% at minimum and yields above 75%. Finally, silicon must be available at $10 to approximately $25/kg, depending on the yield assumed. These conclusions are the final results of the economic analysis. The progress towards the growth of 7.5 cm wide ribbon at 7.5 cm/min is discussed. Also, fluid flow phenomena have been investigated and it is shown that by utilization of such phenomena the impurity distribution in the ribbon may be manipulated to a significant extent. Also, using a somewhat novel ''EBIC'' technique it was demonstrated that the internal grain structure found previously in some ribbons grown at high speeds has virtually no influence on the performance of the material when made into a solar cell.

  14. Spanish paediatric research in ANALES DE PEDIATRÍA: research groups and research areas (2003-2009)

    National Research Council Canada - National Science Library

    González Alcaide, G; Valderrama Zurián, J C; Aleixandre Benavent, R; González de Dios, J

    2011-01-01

    ... to investigate patterns of research collaboration and interactions in scientific community. The objective of this paper is to analyse scientific collaboration and to identify research groups and research areas of ANALES DE PEDIATRÍA...

  15. Hot forming of silicon sheet, silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Final report, May 12, 1976--August 11, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Jr, C D; Pope, D P; Kulkarni, S

    1978-04-14

    Results of an experimental program investigating the hot workability of polytextuerystalline silicon are reported. Uniaxial stress-strain curves are given for strain rates in the range of 10/sup -5/ to 10/sup 1/ sec/sup -1/ and temperatures from 1100 to 1380/sup 0/C. At the highest strain rates at 1380/sup 0/C axial strains in excess of 20% were easily obtainable without cracking; although special preparation of the compression platens allows strains in excess of 50%. After deformations of 36%, recrystallization is completed within 0.1 hr at 1380/sup 0/C. When the recrystallization is ''complete,'' there is still a small volume fraction of unrecrystallized material which appears very stable and may degrade the electronic properties of the bulk material. Texture measurements show that the as-produced vapor deposited polycrystalline rods have a <110> fiber texture with the <110> direction parallel to the growth direction and no preferred orientation about this axis. Upon axial compression perpendicular to the growth direction the former <110> fiber axis changes to <111> and the compression axis becomes <110>. Recrystallization changes the texture to <110> along the former fiber axis and <100> along the compression axis.

  16. Large-Area, UV-Optimized, Back-Illuminated Silicon Photomultiplier Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Large-area (3m2), UV-sensitive focal plane arrays are needed for observation of air showers from ultra-high energy cosmic rays (JEM-EUSO) as well as for...

  17. Energy secretary's priorities include San Francisco area research projects

    CERN Multimedia

    Widener, A

    2003-01-01

    "Bay Area research labs got a big boost Monday when the Secretary of Energy unveiled his priorities for major research projects his agency hopes to fund over the next two decades. Among the agency's 28 top priorities are a major computer expansion and an experiment examining the expanding universe that could be housed at Lawrence Berkeley Lab and a powerful X-ray laser planned for the Stanford Linear Accelerator Center" (1 page).

  18. Silicon and matrix macromolecules: new research opportunities for old diseases from analysis of potential mechanisms of breast implant toxicity.

    Science.gov (United States)

    Brawer, A E

    1998-07-01

    An understanding of the normal and essential integration of the element silicon in biosystems, as well as knowledge of its fundamental chemistry, are crucial to understanding its role in health and disease. Modern organosilicon chemistry, based in part on the artificial silicon-carbon bond, coincided with the emergence of the biomaterials and bioengineering fields fifty years ago, and was thought to be a fortunate coincidence according to conventional wisdom that high-molecular-weight polymeric siloxanes were chemically and biologically inert. These concepts have been challenged by reports of silicone migration and degradation following insertion of gel-filled breast implants, claims of a novel systemic illness appearing in many breast implant recipients, and investigations implicating varied and permeating immunotoxic mechanisms of disease causation by breast devices. The present study develops additional potential pathogenetic ideas based on alterations of cell biochemistry by silicon-containing compounds, and offers correlation of the patients' diverse clinical features with plausable disruption of basic biological processes. This in turn raises new questions concerning everyday environmental exposure, has broad implications for multiple other diseases, can provide alternative directions for future investigative research, and may contribute to the ongoing redefinition of immune dysfunction and inflammation.

  19. Review of Distance Education Research (2000 to 2008): Analysis of Research Areas, Methods, and Authorship Patterns

    Science.gov (United States)

    Zawacki-Richter, Olaf; Backer, Eva Maria; Vogt, Sebastian

    2009-01-01

    This paper presents a review of distance education literature to describe the status thereof and to identify gaps and priority areas in distance education research based on a validated classification of research areas. The articles (N = 695) published in five prominent distance education journals between 2000 and 2008 were reviewed for this study.…

  20. Large area two-dimensional silicon photonic crystals for infrared light fabricated with laser interference lithography

    NARCIS (Netherlands)

    Prodan, L.G.; Euser, T.G.; van Wolferen, Hendricus A.G.M.; Bostan, C.G.; de Ridder, R.M.; Beigang, R.; Boller, Klaus J.; Kuipers, L.

    We report on the production of large-area 2D photonic crystals from high-index material with laser interference lithography (LIL). A new image reversal photoresist is used in combination with an anti-reflection coating to suppress undesired reflections. The photonic crystals possess a cubic pattern

  1. Single-grain Silicon Technology for Large Area X-ray Imaging

    NARCIS (Netherlands)

    Arslan, A.

    2015-01-01

    Digital flat panel X-ray imagers are currently using a-Si and poly-Si thin-film-transistors (TFTs). a-Si TFT permits the use of large area substrates, however, due to the amorphous nature, the carrier mobility is very low (<1 cm2/Vs). Poly-Si TFT improves the mobility (~150 cm2/Vs) but due to random

  2. Engineering Research, Development and Technology, FY95: Thrust area report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the knowledge base, process technologies, specialized equipment, tools and facilities to support current and future LLNL programs. Engineering`s efforts are guided by a strategy that results in dual benefit: first, in support of Department of Energy missions, such as national security through nuclear deterrence; and second, in enhancing the nation`s economic competitiveness through their collaboration with US industry in pursuit of the most cost-effective engineering solutions to LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) identify key technologies relevant to LLNL programs where they can establish unique competencies, and (2) conduct high-quality research and development to enhance their capabilities and establish themselves as the world leaders in these technologies. To focus Engineering`s efforts, technology thrust areas are identified and technical leaders are selected for each area. The thrust areas are comprised of integrated engineering activities, staffed by personnel from the nine electronics and mechanical engineering divisions, and from other LLNL organizations. This annual report, organized by thrust area, describes Engineering`s activities for fiscal year 1995. The report provides timely summaries of objectives methods, and key results from eight thrust areas: computational electronics and electromagnetics; computational mechanics; microtechnology; manufacturing technology; materials science and engineering; power conversion technologies; nondestructive evaluation; and information engineering.

  3. Botanical reconnaissance of The Bowl Research Natural Area.

    Science.gov (United States)

    Lee E. Carbonneau; Sarah D. Allen

    1995-01-01

    The Bowl Research Natural Area is a 206-ha old-growth forest in the White Mountain National Forest of New Hampshire. Elevations range from approximately 580 m along Wonalancet Brook to 1,215 m at the summit of Mt. Whiteface. Vascular vegetation in four Ecological Land Types (ELT's) of the Bowl was characterized on 12 plots and during qualitative meander surveys....

  4. Establishment record for the Wellner Cliffs Research Natural Area

    Science.gov (United States)

    Dennis E. Ferguson; Arthur C. Zack

    2006-01-01

    This publication is the establishment report for Wellner Cliffs Research Natural Area (RNA), located on the Priest River Experimental Forest, Idaho Panhandle National Forests. The RNA features vegetation on dry cliffs that are embedded in mid-elevation moist western hemlock/western redcedar/grand fir forests. Immediately below the cliffs is riparian habitat that...

  5. Plasma etching on large-area mono-, multi- and quasi-mono crystalline silicon

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk; Boisen, Anja

    2013-01-01

    surface recombination. This work shows promising potential of future improvements in power conversion efficiency, since excellent light absorption has been shown for large-area, industry grade CZ Si wafers with several identified areas of improvement. We show that the RIE nanostructures lead to superior...... using maskless RIE in a O2 and SF6 plasma, and the surface topology was optimized for solar cell applications by varying gas flows, pressure, power and process time. The starting substrates were 156x156 mm p-type, CZ mono-, multi- and quasi-mono crystalline Si wafers, respectively, with a thickness...... a significant potential for improvement of solar cell performance compared to current industrial standards. The reflectance is shown to remain below that of conventional textured cells also at high angle of incidence. The process is shown to be equally applicable to mono-, multi- and quasi-mono-crystalline Si...

  6. High-resolution radial distribution function of pure ion-implanted amorphous silicon measured using tilted-illumination selected-area electron diffraction.

    Science.gov (United States)

    Gorecki, Alexander; Liu, Amelia C Y; Petersen, Timothy C

    2014-02-01

    High-resolution radial distribution functions of as-implanted and thermally relaxed amorphous silicon created by ion implantation were measured using tilted-illumination selected area electron diffraction at room temperature. The diffracted intensities were measured out to a maximum scattering vector 2 sin(θ)/λ of 3.3-3.7 Å-1. The volume-averaged pair-correlation statistics of as-implanted and relaxed ion-implanted amorphous silicon are virtually indistinguishable with coordination numbers of 3.7 ± 0.3 and 3.9 ± 0.3 (for neighbors closer than 3 Å) and average bond angles of 109 ± 0.5° and 110 ± 0.6°, respectively. The atomic rearrangements in ion-implanted amorphous silicon due to a low temperature anneal are subtle.

  7. Studying signal collection in the punch-through protection area of a silicon micro-strip sensor using a micro-focused X-ray beam

    CERN Document Server

    Poley, Anne-luise; The ATLAS collaboration

    2018-01-01

    For the Phase-II Upgrade of the ATLAS detector, a new, all-silicon tracker will be constructed in order to cope with the increased track density and radiation level of the High-Luminosity Large Hadron Collider. While silicon strip sensors are designed to minimise the fraction of dead material and maximise the active area of a sensor, concessions must be made to the requirements of operating a sensor in a particle physics detector. Sensor geometry features like the punch-through protection deviate from the standard sensor architecture and thereby affect the charge collection in that area. In order to study the signal collection of silicon strip sensors over their punch-through-protection area, ATLAS silicon strip sensors were scanned with a micro-focused X-ray beam at the Diamond Light Source. Due to the highly focused X-ray beam ($\\unit[2\\times3]{\\upmu\\text{m}}^2$) and the short average path length of an electron after interaction with an X-ray photon ($\\unit[\\leq2]{\\upmu\\text{m}}$), local signal collection i...

  8. Reducing the thermal stress in a heterogeneous material stack for large-area hybrid optical silicon-lithium niobate waveguide micro-chips

    Science.gov (United States)

    Weigel, P. O.; Mookherjea, S.

    2017-04-01

    The bonding of silicon-on-insulator (SOI) to lithium niobate-on-insulator (LNOI) is becoming important for a new category of linear and nonlinear micro-photonic optical devices. In studying the bonding of SOI to LNOI through benzocyclobutene (BCB), a popular interlayer bonding dielectric used in hybrid silicon photonic devices, we use thermal stress calculations to suggest that BCB thickness does not affect thermal stress in this type of structure, and instead, thermal stress can be mitigated satisfactorily by matching the handles of the SOI and LNOI. We bond LNOI with a silicon handle to a silicon chip, remove the handle on the LNOI side, and thermally cycle the bonded stack repeatedly from room temperature up to 300°C and back down without incurring thermal stress cracks, which do appear when using LNOI with a lithium niobate handle, regardless of the BCB thickness. We show that this process can be used to create many hybrid silicon-lithium niobate waveguiding structures on a single patterned SOI chip bonded to a large-area (16 mm × 4.2 mm) lithium niobate film.

  9. Microfabrication of large-area circular high-stress silicon nitride membranes for optomechanical applications

    Directory of Open Access Journals (Sweden)

    E. Serra

    2016-06-01

    Full Text Available In view of the integration of membrane resonators with more complex MEMS structures, we developed a general fabrication procedure for circular shape SiNx membranes using Deep Reactive Ion Etching (DRIE. Large area and high-stress SiNx membranes were fabricated and used as optomechanical resonators in a Michelson interferometer, where Q values up to 1.3 × 106 were measured at cryogenic temperatures, and in a Fabry-Pérot cavity, where an optical finesse up to 50000 has been observed.

  10. Thrust Area Report, Engineering Research, Development and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Langland, R. T.

    1997-02-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the knowledge base, process technologies, specialized equipment, tools and facilities to support current and future LLNL programs. Engineering`s efforts are guided by a strategy that results in dual benefit: first, in support of Department of Energy missions, such as national security through nuclear deterrence; and second, in enhancing the nation`s economic competitiveness through our collaboration with U.S. industry in pursuit of the most cost- effective engineering solutions to LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) identify key technologies relevant to LLNL programs where we can establish unique competencies, and (2) conduct high-quality research and development to enhance our capabilities and establish ourselves as the world leaders in these technologies. To focus Engineering`s efforts technology {ital thrust areas} are identified and technical leaders are selected for each area. The thrust areas are comprised of integrated engineering activities, staffed by personnel from the nine electronics and mechanical engineering divisions, and from other LLNL organizations. This annual report, organized by thrust area, describes Engineering`s activities for fiscal year 1996. The report provides timely summaries of objectives, methods, and key results from eight thrust areas: Computational Electronics and Electromagnetics; Computational Mechanics; Microtechnology; Manufacturing Technology; Materials Science and Engineering; Power Conversion Technologies; Nondestructive Evaluation; and Information Engineering. Readers desiring more information are encouraged to contact the individual thrust area leaders or authors. 198 refs., 206 figs., 16 tabs.

  11. In-house manufacturing of cylindrical silicone models for hemodynamic research

    Science.gov (United States)

    Denisenko, Nikita S.; Kulik, Viktor M.

    2017-10-01

    Laboratory studies of fluid motion in artificial vessels modeling a distinct part of circulatory system of human are of a great importance for fundamental biomechanics and for medical applications. In the medicine they are used for advancing known and developing new methods for curing cardiovascular diseases. In biomechanics, the phantoms of blood vessels are used for studying the fluid motion. However, they are quite expensive. Therefore, a development of technique for in-house manufacturing of phantoms is quite attractive. In this paper methods of manufacturing cylindrical channels of silicone rubbers (the model of the straight part of an artery) and determination of their elastic properties are described. A specially developed acrylic mold is used for this purpose. The phantoms are cast from a mixture of SKTN-A silicone and PMS-5 oil (Penta-91, Novosibirsk, Russia). The oil is used for changing elasticity properties of the silicone.

  12. Impact of silicon doping on InAs nanowires grown by selective area MOVPE

    Energy Technology Data Exchange (ETDEWEB)

    Sladek, Kamil; Penz, Andreas; Wirths, Stephan; Weis, Karl; Lenk, Steffi; Hardtdegen, Hilde; Schaepers, Thomas; Gruetzmacher, Detlev [Institute of Bio- and Nanosystems (IBN-1), Juelich Aachen Research Alliance (JARA), Forschungszentrum Juelich, 52425 Juelich (Germany); Luysberg, Martina [Institute of Solid State Research and Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Juelich (Germany)

    2010-07-01

    InAs nanowires are an attractive candidate for the realization of high-speed and low-power electronic devices due to the material's very high room temperature mobility. However, as recently reported by Dayeh et al. their conductivity could be influenced negatively by often observed stacking faults. In this contribution, we have investigated the influence of Si-doping during growth with the aim to tune nanowire conductivity and crystalline structure. The nanowires were deposited by selective area MOVPE on (111)B GaAs masked substrates. The samples were characterized structurally by transmission and scanning electron microscopy. We observed that above a certain partial pressure ratio, doping has an influence on morphology. The nanowires exhibit higher uniformity and specific conductance, but decreasing height vs. diameter aspect ratio as the partial pressure ratio increases. This leads to the question, whether the incorporation of doping atoms or a structural change has the main influence on conductivity.

  13. GaAs Solar Cells on V-Grooved Silicon via Selective Area Growth: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Emily L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jain, Nikhil [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tamboli, Adele C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Vaisman, Michelle [Yale University; Li, Qiang [Hong Kong University of Science and Technology; Lau, Kei May [Hong Kong University of Science and Technology

    2017-08-31

    Interest in integrating III-Vs onto Si has recently resurged as a promising pathway towards high-efficiency, low-cost tandem photovoltaics. Here, we present a single junction GaAs solar cell grown monolithically on polished Si (001) substrates using V-grooves, selective area growth, and aspect ratio trapping to mitigate defect formation without the use of expensive, thick graded buffers. The GaAs is free of antiphase domains and maintains a relatively low TDD of 4x107 cm-2, despite the lack of a graded buffer. This 6.25 percent-efficient demonstration solar cell shows promise for further improvements to III-V/Si tandems to enable cost-competitive photovoltaics.

  14. Political communication science as a research area: history and contemporaneity

    Directory of Open Access Journals (Sweden)

    Chekunova Marina A.

    2016-01-01

    Full Text Available This article presents main markers of the research line named political communication science. The analysis of the foreign literature has allowed the author not only to establish the stages and the current status of the mentioned research field but to demonstrate the current level of knowledge of political communication. This article reveals the tight interrelation between genesis of political communication science and the theoretical understanding of state administration, efficiency and legitimacy of administrative authority decisions. The research area of the western political system was shown restricted up to the solution of particular issues, whereby the author considers the problem how to move the political сcommunication science to a new level by means of expansion of research interest in media sphere, political advertizing, PR and even awareness campaign.

  15. Design and Research on Automotive Controller Area Network Bus Analyzer

    Directory of Open Access Journals (Sweden)

    Hongwei CUI

    2014-03-01

    Full Text Available The detection method of automotive controller area network bus is researched in this paper. Failure identifying of CAN bus under different working conditions has been realized. In order to realizing intelligent failure diagnosis, data fusion means has been put forward in this paper. The composition of analysis and detection system is introduced. By analyzing and processing the data of CAN bus and sensors, work condition of automotive is achieved. Multi-pattern data fusion model and algorithm for failure diagnosis are researched. The analyzer and detection system designed in this paper can be applied to automotive fault analysis, troubleshooting and maintenance.

  16. Research of sanitary, chemical and toxicological properties of silicone material «Silast-M» for removable dentures

    Directory of Open Access Journals (Sweden)

    Lebedenko I.Yu.

    2013-09-01

    Full Text Available Objective: to conduct sanitary, chemical and toxicological testing of the domestic cold-curing silicone material «Silast-M» for removable dentures. The object of the study included samples of silicone material «Silast-M» developed by CJSC «MEDSIL» in cooperation with the Department of Moscow State Medico-Stomatological University n.a. A. I. Evdokimov. Laboratory studies were carried out in the department of toxicology testing and researching materials and medical products VNIIIMT in accordance with the instructions on the sanitary, chemical and toxicological studies, developed and approved by the Ministry of Health of the Russian Federation. The results showed that all samples did not exceed the limit values. Conclusion. After successfully passed sanitary, chemical and toxicological studies clinical trials of the material have been started.

  17. Engineering research, development and technology. Thrust area report, FY93

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the technical staff, tools, and facilities needed to support current and future LLNL programs. The efforts are guided by a dual-benefit research and development strategy that supports Department of Energy missions, such as national security through nuclear deterrence and economic competitiveness through partnerships with U.S. industry. This annual report, organized by thrust area, describes the activities for the fiscal year 1993. The report provides timely summaries of objectives, methods, and results from nine thrust areas for this fiscal year: Computational Electronics and Electromagnetics; Computational Mechanics; Diagnostics and Microelectronics; Fabrication Technology; Materials Science and Engineering; Power Conversion Technologies; Nondestructive Evaluation; Remote Sensing, Imaging, and Signal Engineering; and Emerging Technologies. Separate abstracts were prepared for 47 papers in this report.

  18. Brazilian pediatric research groups, lines of research, and main areas of activity.

    Science.gov (United States)

    Oliveira, Priscila H A; Pinheiro, Mariana G; Isquierdo, Larissa A; Sukiennik, Ricardo; Pellanda, Lucia C

    2015-01-01

    The Brazilian scientific production in the pediatrics field has been increasing significantly. It is important to identify the distribution and activity of these groups in the country and the main study areas, contributing with data for better resource allocation by institutions. An active research was conducted in the National Council of Technological and Scientific Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico [CNPq]) website, using as filters the macro area of the research group (Health Sciences), the area (Medicine), and descriptors related to pediatrics. Research lines and main area of pediatric research groups were classified according to the subject predominantly studied by each group. The scientific production of the leader of the pediatric research group between 2011 and 2014 was also analyzed. Most pediatric research groups in Brazil have more than five years of activity and are concentrated in the Southeast and South regions of the country; São Paulo, Rio Grande do Sul, and Minas Gerais are the states with most groups. Of the 132 specific pediatric research groups analyzed, 14.4% have lines of research in multiple areas and 11.4% in child and adolescent health. Among the 585 lines of research of these groups, the most prevalent areas were: oncology, infectious diseases, epidemiology, and gastroenterology. The pediatric research groups in Brazil have relevant scientific production, including works published in international publications, and are concentrated in regions with higher socioeconomic index. Most groups registered in CNPq started their activity in the last five years (46%), reflecting the recent growth of scientific production in this area. Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  19. The chemistry of silicon

    CERN Document Server

    Rochow, E G; Emeléus, H J; Nyholm, Ronald

    1975-01-01

    Pergamon Texts in Organic Chemistry, Volume 9: The Chemistry of Silicon presents information essential in understanding the chemical properties of silicon. The book first covers the fundamental aspects of silicon, such as its nuclear, physical, and chemical properties. The text also details the history of silicon, its occurrence and distribution, and applications. Next, the selection enumerates the compounds and complexes of silicon, along with organosilicon compounds. The text will be of great interest to chemists and chemical engineers. Other researchers working on research study involving s

  20. Development of Tandem Amorphous/Microcrystalline Silicon Thin-Film Large-Area See-Through Color Solar Panels with Reflective Layer and 4-Step Laser Scribing for Building-Integrated Photovoltaic Applications

    Directory of Open Access Journals (Sweden)

    Chin-Yi Tsai

    2014-01-01

    Full Text Available In this work, tandem amorphous/microcrystalline silicon thin-film large-area see-through color solar modules were successfully designed and developed for building-integrated photovoltaic applications. Novel and key technologies of reflective layers and 4-step laser scribing were researched, developed, and introduced into the production line to produce solar panels with various colors, such as purple, dark blue, light blue, silver, golden, orange, red wine, and coffee. The highest module power is 105 W and the highest visible light transmittance is near 20%.

  1. Fire Process Research Natural Areas: Managing research and restoration of dynamic ecosystem processes

    Science.gov (United States)

    Timothy Ingalsbee

    2001-01-01

    Since 1992 a collaborative group of fire scientists, forest conservationists, and Federal resource specialists have been developing proposals for a Research Natural Area (RNA) in the Warner Creek Fire area on the Willamette National Forest in Oregon. Inspired by these proposals, the Oregon Natural Heritage Plan created the new category of "Fire Process RNAs"...

  2. Nanoinformatics: a new area of research in nanomedicine

    Science.gov (United States)

    Maojo, Victor; Fritts, Martin; de la Iglesia, Diana; Cachau, Raul E; Garcia-Remesal, Miguel; Mitchell, Joyce A; Kulikowski, Casimir

    2012-01-01

    Over a decade ago, nanotechnologists began research on applications of nanomaterials for medicine. This research has revealed a wide range of different challenges, as well as many opportunities. Some of these challenges are strongly related to informatics issues, dealing, for instance, with the management and integration of heterogeneous information, defining nomenclatures, taxonomies and classifications for various types of nanomaterials, and research on new modeling and simulation techniques for nanoparticles. Nanoinformatics has recently emerged in the USA and Europe to address these issues. In this paper, we present a review of nanoinformatics, describing its origins, the problems it addresses, areas of interest, and examples of current research initiatives and informatics resources. We suggest that nanoinformatics could accelerate research and development in nanomedicine, as has occurred in the past in other fields. For instance, biomedical informatics served as a fundamental catalyst for the Human Genome Project, and other genomic and –omics projects, as well as the translational efforts that link resulting molecular-level research to clinical problems and findings. PMID:22866003

  3. Establishing a research and demonstration area initiated by managers: the Sharkey Restoration Research and Demonstration Site

    Science.gov (United States)

    E. Gardiner; J. Stanturf; T. Leininger; P. Hamel; L. Jr. Dorris; J. Portwood; J. Shepard

    2008-01-01

    As forest scientists increase their role in the process of science delivery, many research organizations are searching for novel methods to effectively build collaboration with managers to produce valued results. This article documents our experience with establishment of a forest restoration research and demonstration area in the Lower Mississippi Alluvial Valley (...

  4. Review of Distance Education Research (2000 to 2008: Analysis of Research Areas, Methods, and Authorship Patterns

    Directory of Open Access Journals (Sweden)

    Olaf Zawacki-Richter

    2009-12-01

    Full Text Available This paper presents a review of distance education literature to describe the status thereof and to identify gaps and priority areas in distance education research based on a validated classification of research areas. The articles (N = 695 published in five prominent distance education journals between 2000 and 2008 were reviewed for this study. The conclusion is that distance education research is strongly dominated by issues related to instructional design and individual learning processes; whereas, other important areas (e.g., innovation and change management or intercultural aspects of distance learning are dreadfully neglected. There is a significant trend towards collaborative research and more qualitative studies. Over 80% of all articles originate from only five countries.

  5. Heat exchanger-ingot casting/slicing process. Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Final report, Phase I, November 20, 1975--November 20, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, F; Khattak, C P

    1977-12-01

    The proof of concept for silicon casting by the Heat Exchanger Method has been established. One of the major hurdles of ingot cracking has been eliminated with the development of graded crucibles. Such crucibles are compatible with the casting process in that the integrity of the container is maintained at high temperature; however, during the cool-down cycle the crucible fails, thereby leaving a crack-free boule. The controlled growth, heat-flow and cool-down has yielded silicon with a high degree of single crystallinity. Even when the seed melted out, very large grains formed. Solar cell samples made from cast material have yielded conversion efficiency of over 9% (AMI). Representative characterizations of silicon grown has demonstrated a dislocation density of less than 100/cm/sup 2/ and a minority carrier diffusion length of 31 ..mu..m. Excellent surface quality, i.e., surface smoothness and 3 to 5 ..mu..m surface damage, was achieved by multiple wire slicing with fixed diamond abrasive. To achieve this, the silicon workpiece was non-synchronously rocked to produce a radial cut profile and minimize wire contact length. Wire wander was reduced an order of magnitude over the original results by supporting and guiding the wires with grooved rollers. Commercially available impregnated wires that were used failed due to diamond pull-out. Plating after impregnation or electroplating diamonds directly on the core minimized diamond pull-out and corresponding loss in cutting effectiveness. Tungsten wire was the best core material tested because of its high strength, high Young's modulus, and resistance to hydrogen embrittlement. A lighter and longer blade carriage can be used for slicing with wire. This will allow the blade carriage to be reciprocated more rapidly to increase the surface speed. A projected add-on cost calculation shows that these methods will yield silicon for solar cell applications within ERDA/JPL cost goals.

  6. NATO Advanced Research Workshop on Environmental and Biological Risks of Hybrid Organic-Silicon Nanodevices

    CERN Document Server

    Kozyrev, Sergey; Vaseashta, Ashok

    2009-01-01

    Even though there is no generally accepted definition of nanotechnologies to be defined as distinct discipline there is an emerging consensus that their advent and development is a growing in importance factor of the contemporary and future technological civilization. One of these most fundamental issues we are confronted with is the compatibility with life itself. From single cell organisms to humans, carbon is a key building block of all molecular structures of life. In contrast the man created electronic industry to build on other elements, of which silicon is the most common. Both carbon and silicon create molecular chains, although different in their internal structure. All life is built from carbon-based chains. As long as the man built technological products do not directly interfere with the physiology of life the associated risks from them are relatively easy to identify. They are primarily in the environmental pollution and the possibility of upsetting the natural balance of biocoenosis, on a planet...

  7. LSA large area silicon sheet task, continuous liquid feed Czochralski growth. Quarterly report No. 4, July--September 1978

    Energy Technology Data Exchange (ETDEWEB)

    Fiegl, G.

    1978-09-01

    Siltec Corporation's contract with JPL is directed towards the design and development of equipment and processes, to demonstrate continuous growth of crystals by the Czochralski method, suitable for producing single silicon crystals for use in solar cells. Continuous growth is defined as the growth of 100 Kg of single silicon crystal, 10 cm in diameter, from one container. Siltec's approach to meeting this goal is to develop a furnace with continuous liquid replenishment of the growth crucible, accomplished by a melt-down system and a liquid transfer mechanism, with associated automatic feedback controls. Fabrication of all furnace parts was completed during the past quarter. Mechanical assembly of the furnace was accomplished and all electrical work completed. The furnace underwent final systems testing and is now ready for test runs. Two crystals from 15 Kg charges were grown by conventional CZ technique. Simulated transfer of molten silicon was performed using a liquid of approximately the same kinematic viscosity as that of molten silicon. A study was made to determine the effects of a stationary 7 mm O.D. quartz tube submerged into the molten silicon in the rotating crucible during the growth of a 2-inch diameter crystal. Results are reported.

  8. Porous silicon gettering

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S.; Menna, P.; Al-Jassim, M. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-08-01

    We have studied a novel extrinsic gettering method that utilizes the very large surface areas, produced by porous silicon etch on both front and back surfaces of the silicon wafer, as gettering sites. In this method, a simple and low-cost chemical etching is used to generate the porous silicon layers. Then, a high-flux solar furnace (HFSF) is used to provide high-temperature annealing and the required injection of silicon interstitials. The gettering sites, along with the gettered impurities, can be easily removed at the end the process. The porous silicon removal process consists of oxidizing the porous silicon near the end the gettering process followed by sample immersion in HF acid. Each porous silicon gettering process removes up to about 10 {mu}m of wafer thickness. This gettering process can be repeated so that the desired purity level is obtained.

  9. Exploration of maximum count rate capabilities for large-area photon counting arrays based on polycrystalline silicon thin-film transistors

    Science.gov (United States)

    Liang, Albert K.; Koniczek, Martin; Antonuk, Larry E.; El-Mohri, Youcef; Zhao, Qihua

    2016-03-01

    Pixelated photon counting detectors with energy discrimination capabilities are of increasing clinical interest for x-ray imaging. Such detectors, presently in clinical use for mammography and under development for breast tomosynthesis and spectral CT, usually employ in-pixel circuits based on crystalline silicon - a semiconductor material that is generally not well-suited for economic manufacture of large-area devices. One interesting alternative semiconductor is polycrystalline silicon (poly-Si), a thin-film technology capable of creating very large-area, monolithic devices. Similar to crystalline silicon, poly-Si allows implementation of the type of fast, complex, in-pixel circuitry required for photon counting - operating at processing speeds that are not possible with amorphous silicon (the material currently used for large-area, active matrix, flat-panel imagers). The pixel circuits of two-dimensional photon counting arrays are generally comprised of four stages: amplifier, comparator, clock generator and counter. The analog front-end (in particular, the amplifier) strongly influences performance and is therefore of interest to study. In this paper, the relationship between incident and output count rate of the analog front-end is explored under diagnostic imaging conditions for a promising poly-Si based design. The input to the amplifier is modeled in the time domain assuming a realistic input x-ray spectrum. Simulations of circuits based on poly-Si thin-film transistors are used to determine the resulting output count rate as a function of input count rate, energy discrimination threshold and operating conditions.

  10. Achievement report for fiscal 1997 on developing a silicon manufacturing process with reduced energy consumption. Investigation and research on analyzing practical application of a technology to manufacture solar cell silicon raw materials; 1997 nendo energy shiyo gorika silicon seizo process kaihatsu. Taiyo denchi silicon genryo seizo gijutsu no jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This paper describes the achievement in fiscal 1997 of analyzing practical application of a technology to manufacture solar cell silicon raw materials. Silicon consumption for solar cells in fiscal 1997 has increased to 2000-ton level, and the supply has been very tight. For drastic improvement in the demand and supply situation, development of SOG-Si manufacturing technology and its early practical application are desired. The development of the NEDO mass-production technology using melting and refining has completed constructing the process facilities in fiscal 1998, and will enter the stage of operational research. However, insufficiency in the basic data about behavior of impurities is inhibiting the development. In the substrate manufacturing technology, discussions have shown progress on use of diversifying silicons outside the standard by using the electromagnetic casting process. For slicing and processing the substrates, development of a high-performance slicing equipment and automatic rough rinsing machine is under way. Properties required on silicon raw materials vary considerably widely because of difference in cell making systems and conditions, which is attributable to unknown impurity behavior. When 1GW production is assumed, the cell module manufacturing cost is calculated as 137 yen/W, for which low-cost mass production for its realization, slicing productivity enhancement, and cost reduction are required. The paper also describes site surveys in overseas countries. (NEDO)

  11. Advanced Silicon Chemistry in Australia: Forming Strong Links with Asia.

    Science.gov (United States)

    Clarke, Stephen; Nguyen, Kim-Anh Thi; Markovic, Elda; Trout, Neil; Ginic-Markovic, Milena; Matisons, Janis; Owen, Michael; Graiver, Daniel; Wargadipura, Agus Hadi Santosa; Habibie, Sudirman; Gustiono, Dwi; Yoo, Bok Ryul; Mifsud, Joe

    2017-06-01

    This paper details Australian commercial and academic silicon research. Areas of interest include silicon metal, polysiloxane polymers, copolymers, cyclics, emulsions, microemulsions, silanes, silane coupling agents, sol-gel chemistry and water-treatments, porous silicon, polysiloxane degradation, silicon hydrogel contact lenses, silanolate synthesis, siloxane interfacial polymerisation, hydrosilylation, polysiloxane electrolytes for lithium ion batteries, silanes for PBX materials, octafunctionalized polyhedral oligomeric silsesquioxanes (POSS), POSS hybrids, sol-gel hydrogenation catalysts, silane modification of silica, sol-gel energy storage, silicate grout stabilisation, GeoPolymer concretes, aerogel insulating foams, "Phaco-Ersatz" Accommodating Gel-Intraocular Lens technologies. Strong collaborative opportunities, in silicon, with Asia, exist with organisations such as: 1) The Asian Silicon Society and 2) The Agency for the Assessment and Application of Technology (BPPT) Indonesia. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Information Support of Russian Universities in Core Research Areas

    Directory of Open Access Journals (Sweden)

    Irina K. Razumova

    2017-09-01

    Full Text Available Introduction: integration of scientific literature into education process, information support of teaching and research with scholarly information directly impacts the level of education and science and thus determine national and international university ranking and reputation. National system of information support for science and education has been established and successfully developed in Russia since 2006. The system provides access to subscribed scholarly resources. At the current stage of development of the national-wide information support, the key role belongs to the state-funded projects. The authors outline the problem of quantitative assessment of the level of information support in fields of scienc e in respect to different classificators. Materials and Methods: the study draws on bibliometric methods, keyword searches and analytical services and functionality of Web of Science Core Collection database. Materials and instruments include lists of resources subscribed within the projects of the Ministry of Education and Science of the Russian Federation and Russian Foundation for Basic Research; sets of articles downloaded as a result of keyword searches; journal title lists of the WoS CC and Scopus and mappings of the WoS Categories and fields of science in classifications of OECD and the Ministry of Education and Scien ce of the Russian Federation. Results: we defined and calculated quantitative values of the parameter of information support for five priority areas of development of the Russian scientific and technological complex and six fields of science of the first level of the OECD classification and six branches of science used in the assessment of higher education institutions performed by the Ministry of Education a nd Science of the Russian Federation. Discussion and Conclusions: we compared results of the information support analysis for three subscription years 2015, 2016 and 2017. We found that the level of information

  13. The Forming Process Researched in Sandblasting Separation of Masked Silicon Wafers

    Directory of Open Access Journals (Sweden)

    V. V. Zhukov

    2016-01-01

    Full Text Available The object of study is a semiconductor silicon disc-crystal currently used in the design of semiconductor diodes. The disc-crystal is manufactured by the sandblasting separation of a premasked silicon wafer into individual elements. The crystal has frustum-of-a-cone shape with its top diameter determined by a protective masking disc diameter and the bottom one defined by the features of the forming process. The apex angle of the cone 2α or a half-angle α between the lateral surface of the cone and the normal drawn to its base is used as a reference value.The work has studied the influence a thickness of the separated wafer and a width of the gap between the masked discs on the crystal shape. The masking cover is a set of square protective elements (3x3 mm, spaced at 0.6; 0.7; 0.8 and 0.9 mm. The mask material is a self-adhesive PVC-film with thickness of 200 microns. Pilot-plant semi-automatic sandblasting equipment was used to for separation.After processing of results (the angle 2α at the top of the cone the following conclusions have been made:- with increasing thickness of the silicon wafers the gap between the protective discs of mask must be increased;- in case a range of the minimum gaps between the protective discs is within 0.35 - 1.20 mm the half-angle α, which defines the shape of the cut surface, can be considered to be constant and equal to 12º ... 14º.

  14. Mr. Lorenzo Dellai, presidente della provincia Autonoma di Trento and Professor Andrea Zanotti, president dell'Instituto Trentino di Cultura, visit ALICE experiment underground area and Pixel Silicon Laboratory

    CERN Multimedia

    Claudia Marcelloni

    2006-01-01

    Mr. Lorenzo Dellai, presidente della provincia Autonoma di Trento and Professor Andrea Zanotti, president dell'Instituto Trentino di Cultura, visit ALICE experiment underground area and Pixel Silicon Laboratory

  15. Research at Hanford's 300 Area Integrated Field Challenge Site

    Science.gov (United States)

    Zachara, J.; Rockhold, M.; Fredrickson, J.; Vermeul, V.; Ward, A.; Liu, C.; McKinley, J.; Bjornstad, B.; Freshley, M.; Haggerty, R.; Kent, D.; Lichtner, P.; Rubin, Y.; Versteeg, R.; Zheng, C.

    2008-12-01

    The U.S. Department of Energy - Environmental Remediation Sciences Division is supporting an Integrated Field Challenge (IFC) Site at Hanford's 300 Area. This site, immediately adjacent to the Columbia R., is the location of a groundwater uranium plume that resulted from past discharges of liquid effluent to unlined disposal ponds and trenches. Plume concentrations have persisted above the drinking water standard in spite of the cessation of all liquid discharges more than 15 years ago and significant efforts to excavate and remove contaminated sediments. The persistence of the uranium plume is postulated to be a result of a complex interplay between hydrological, geochemical, and microbiological processes, and rate-limited mass transfer in the highly heterogeneous sediments. An IFC research site has been established in the area of one of the former disposal ponds to provide the infrastructure for developing improved understanding of the mechanisms responsible for the uranium plume persistence, with an ultimate goal of providing a robust, scientific basis for future remediation decisions. Thirty-five wells were installed at the site in FY08 for subsurface characterization and monitoring of field experiments. Detailed characterization studies have been performed or are currently underway using a variety of hydrological, geophysical, geochemical, and microbiological methods. In addition to field experiments, a series of column and bench-scale transport experiments are being performed to measure process interactions at smaller scales under well-controlled laboratory conditions, and to parameterize mechanistically-based model representations of these processes. This presentation gives an overview of guiding hypotheses for the 300 Area IFC Site, the well layout and instrumentation, initial characterization results, and ongoing or planned experiments and modeling activities.

  16. 75 FR 1115 - Invitation for Public Comment on Strategic Research Direction, Research Priority Areas and...

    Science.gov (United States)

    2010-01-08

    ... priorities include: Safety--Fostering a safety culture in our daily work and encouraging our partners... options to promote increased access to jobs, school, health services, and other activities for our... multimodal transportation system, and is setting strategies to address research areas that stress a multi...

  17. International Conflict Studies as a Research and Teaching Area

    Directory of Open Access Journals (Sweden)

    Alexandra Viktorovna Khudaykulova

    2015-12-01

    Full Text Available The article analyzes international conflict studies as a science and an educational discipline. The analysis of the subject field and professional terminology adopted in this area both in Russian and in English is provided. Formation of international conflict studies as a distinct field of study in the United States and Western Europe is described. The results of analysis of 10 leading foreign schools on international conflict studies are presented. The main factors that were taken into account in identifying the leading centers were the existence of a separate research (educational analysis units of international conflicts, the world's leading scientific journals on conflict resolution, as well as databases for the analysis of international conflicts. The role of professional associations, education consortia and international organizations (UNESCO in the study of international conflicts is described. An analysis of the leading think tanks on defense and national security (as rated by Philadelphia think tank ranking is also provided. Particular attention is given to interdisciplinary research methodology of international conflicts and the structure of educational programs at leading schools in the world in international relations. The author summarizes the recommendations of the Association of Professional Schools of International Affairs (APSIA to create educational programs of this kind.

  18. Plutonium Focus Area research and development plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The Department of Energy (DOE) committed to a research and development program to support the technology needs for converting and stabilizing its nuclear materials for safe storage. The R and D Plan addresses five of the six material categories from the 94-1 Implementation Plan: plutonium (Pu) solutions, plutonium metals and oxides, plutonium residues, highly enriched uranium, and special isotopes. R and D efforts related to spent nuclear fuel (SNF) stabilization were specifically excluded from this plan. This updated plan has narrowed the focus to more effectively target specific problem areas by incorporating results form trade studies. Specifically, the trade studies involved salt; ash; sand, slag, and crucible (SS and C); combustibles; and scrub alloy. The plan anticipates possible disposition paths for nuclear materials and identifies resulting research requirements. These requirements may change as disposition paths become more certain. Thus, this plan represents a snapshot of the current progress and will continue to be updated on a regular basis. The paper discusses progress in safeguards and security, plutonium stabilization, special isotopes stabilization, highly-enriched uranium stabilization--MSRE remediation project, storage technologies, engineered systems, core technology, and proposed DOE/Russian technology exchange projects.

  19. Quantitative analysis of defects in silicon: silicon sheet growth development for the Large Area Silicon Sheet Task of the Low-Cost Solar Array Project. Quarterly progress report No. 5, April 1-June 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Natesh, R.; Smith, J.M.; Qidwai, H.A.; Bruce, T.

    1979-07-12

    During this reporting period a computer program was written for the PDP 11/03 computer that controls the Quantimet 720 Image Analyzing System (QTM 720). This program will facilitate the analysis of silicon samples on the upgraded Quantimet 720 System. Also during this period thirty-two (32) Motorola samples were analyzed for twin boundaries, dislocation pits, and grain boundaries. A discussion of the computer program and the data obtained from the thirty-two (32) Motorola samples are given. The use of the Image Editor on the QTM 720 detected image is also described.

  20. Complex research of the areas of the Moon gravity anomalies.

    Science.gov (United States)

    Pugacheva, Svetlana

    The report presents the results of a research study of the lunar surface in the areas of gravity anomalies. The source of gravity anomalies of the Moon are large mascons with a high mass concentration at a depth of volcanic plains and lunar Maria. Formation of mascons is connected with intensive development of basaltic volcanism on the Moon in the early periods of its existence. Many volcanic structures have been found by the Grail spacecraft. These are tectonic structures, basins of impact craters, ancient linear gravity anomalies. The article presents the data of physical and mechanical properties of the surface soil layer of the lunar Maria and gives an assessment of the chemical composition of the soil. All measurements have been performed according to the theoretical models of light scattering on the basis of survey of the lunar surface by in-orbit spacecrafts and analysis of the lunar soil samples. There have been calculated heterogeneity parameters of the surface macro-relief of the lunar Maria: albedo, soil density, average grain diameter of the particles forming the surface layer and the volume fraction occupied by particles. Previous articles showed correlation dependence of the chemical composition of rocks on the macrostructure of the lunar surface. The surface macrostructure was evaluated by comparing the local phase function with the lunar spatial scattering indicatrix. Phase function difference at an 18-degree phase is properly consistent with the chemical composition of the surface layer of soil, in particular with the content of thorium and iron oxide. It can be assumed that mascons include rich KREEP rocks with a high content of thorium and iron oxide. KREEP rocks in the areas of the lunar Maria covered by volcanic lava are probably located on the surface or at a shallow depth.

  1. Silicon Based Photovoltaic Cells For Concentration-Research And Development Progress In Laser Grooved Buried Contact Cell Technology

    Science.gov (United States)

    Cole, A.; Baistow, I.; Brown, L.; Devenport, S.; Drew, K.; Heasman, K. C.; Morrison, D.; Bruton, T. M.; Serenelli, L.; De Iuliis, S.; Izzi, M.; Tucci, M.; Salza, E.; Pirozzi, L.

    2011-12-01

    The Laser grooved buried contact silicon solar cell (LGBC) process employed by Narec currently produces LGBC cells designed to operate at concentrations ranging from 1-100 suns and has demonstrated efficiencies at 50X of over 19% and at 100X of over 18.2% using 300 μm CZ silicon[1] wafers. As part of the LAB2LINE[1], APOLLON[2] and ASPIS[3] projects funded under the European Commission Framework Programs (FP6 and FP7) we have made improvements to the LGBC process to improve efficiency or make the cell technology more suitable for industrial CPV receiver manufacturing processes. We describe a process which hybridizes LGBC and more standard screen printing technologies which yields at least a 6% relative improvement at concentration when using more readily available 200 μm thick CZ wafers. We describe a pioneering front dicing technique (FDT). The FDT process is important in small cells where edge recombination effects are detrimental to the performance. We show that by using this new technique we can produce cells that perform better at concentration and improve the positioning of the front contact of the cell. We also describe a busbar technology that uses laser processing and electroless chemical plating to allow not only soldering to the front contact of the cell but also wire bonding. The advances in research and development of LGBC cells leading to improved cell performance may provide significant reductions in levilised cost of energy (LCOE) for low to medium CPV systems.

  2. Research of 915nm laser power beaming to monocrystal silicon solar cells

    Science.gov (United States)

    Zhang, Yu; Chen, Minsun; Jiang, Houman; Zhao, Guomin

    2015-08-01

    The properties of 915nm laser power beaming to monocrystal silicon solar cells are investigated by measuring IV curves, temperature and etc. With the illumination intensity increased from 0.04W/cm2 to 0.58W/cm2, short-circuit current increases almost linearly from 0.14A to a maximum value of 3.07A. While the maximum power output peaks at a lower irradiation intensity of 0.46W/cm2, which can be also regarded as a turning point where IV curves begin to deteriorate from normal ones to oblique lines. During the period, the fill factor decreases continuously from around 74% to a stable value of 25%. To understand the experiment more clearly, theoretical analyses are conducted by virtue of Lambert W function. Based on the analyses, it can be concluded that the primary culprits influencing the cell's output performance are the temperature and series resistance.

  3. ENSAR, a Nuclear Science Project for European Research Area

    NARCIS (Netherlands)

    Turzó, Ketel; Lewitowicz, Marek; Harakeh, Muhsin N.

    2015-01-01

    During the period from September 2010 to December 2014, the European project European Nuclear Science and Applications Research (ENSAR) coordinated research activities of the Nuclear Physics community performing research in three major subfields: Nuclear Structure, Nuclear Astrophysics, and Nuclear

  4. [Spanish paediatric research in ANALES DE PEDIATRÍA: research groups and research areas (2003-2009)].

    Science.gov (United States)

    González Alcaide, G; Valderrama Zurián, J C; Aleixandre Benavent, R; González de Dios, J

    2011-04-01

    Authorships of scientific papers are a significant milestone for researchers. Quantification of authors' contribution in research papers makes it possible to investigate patterns of research collaboration and interactions in scientific community. The objective of this paper is to analyse scientific collaboration and to identify research groups and research areas of ANALES DE PEDIATRÍA. Papers published in ANALES DE PEDIATRÍA between 2003 and 2009 period were selected from Medline. An author name normalization process was carried out. Productivity and scientific collaboration indexes have been determined. Research groups have been identified through co-authorships networks analysis. Thematic areas of research and major domains of research groups have been characterised by means of quantification of Medical Subject Headings terms assigned to documents. An analysis was made of 1,828 documents published by 4,695 authors. The collaboration index (articles) was 5.3 ± 2.3. A total of 97 research groups consisting of between 2 and 80 researchers, which add up 415 researchers have been identified. The main diseases and medical signs studied were asthma (n = 35), multiple abnormalities (n = 28), premature diseases (n = 25), sepsis (n = 24), congenital heart defects (n = 23), respiratory insufficiency (n = 22), HIV infections (n = 21), streptococcal infections (n = 20) and gastroenteritis (n = 20). ANALES DE PEDIATRÍA is one of the most productive Spanish medical journals. Author's collaboration was similar to those observed in other Spanish clinical journals included in Journal Citation Reports. A remarkable number of paediatric research groups publishing on many topics have been identified. Copyright © 2010 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  5. Fundamental Research and Development for Improved Crystalline Silicon Solar Cells: Final Subcontract Report, March 2002 - July 2006

    Energy Technology Data Exchange (ETDEWEB)

    Rohatgi, A.

    2007-11-01

    This report summarizes the progress made by Georgia Tech in the 2002-2006 period toward high-efficiency, low-cost crystalline silicon solar cells. This program emphasize fundamental and applied research on commercial substrates and manufacturable technologies. A combination of material characterization, device modeling, technology development, and complete cell fabrication were used to accomplish the goals of this program. This report is divided into five sections that summarize our work on i) PECVD SiN-induced defect passivation (Sections 1 and 2); ii) the effect of material inhomogeneity on the performance of mc-Si solar cells (Section 3); iii) a comparison of light-induced degradation in commercially grown Ga- and B-doped Czochralski Si ingots (Section 4); and iv) the understanding of the formation of high-quality thick-film Ag contacts on high sheet-resistance emitters (Section 5).

  6. Optical signal processing by silicon photonics

    CERN Document Server

    Ahmed, Jameel; Adeel, Freeha; Hussain, Ashiq

    2014-01-01

    The main objective of this book is to make respective graduate students understand the nonlinear effects inside SOI waveguide and possible applications of SOI waveguides in this emerging research area of optical fibre communication. This book focuses on achieving successful optical frequency shifting by Four Wave Mixing (FWM) in silicon-on-insulator (SOI) waveguide by exploiting a nonlinear phenomenon.

  7. A review on the establishment and research in hydrological experimental areas (catchments) in plain areas in China and abroad

    Science.gov (United States)

    Yang, Hai; Wang, Chuanhai; Hua, Wenjuan

    2017-04-01

    This paper reviewed some specific conceptions of hydrological experimental areas (catchments) while found that the traditional definition of 'catchment' may be difficult to meet in plain areas. According to the review of development history and current situation of hydrological experimental areas (catchments) in plain areas in China, 4 stages were shown besides the recent 10 years, i.e., 'golden stage(1952-1966)', 'backward stage(1966-1986)', 'short recovery stage(1986-1989)' and 'stagnant stage(1986-2006)'. It gets new impetus since 2006 with some investigation work promoted by the government. Furthermore, some historic problems during establishing experimental areas (catchments) in plain areas were revealed based on the document literature and a few meaningful lessons were drawn from the past. It was also the first time to collect and classify the details of both 11 representative experimental areas in China and abroad, after that a brief comparison about the measurement level and research directions was made between two regions. Additionally, we took the experimental research work in the plain of Taihu Lake Basin as example and introduced the particular research goals and the corresponding establishing process, including how to design the experimental area, eg, size, location, land use type, arranging the measurement instruments et al. We hope such case can provide a reference for newly-building, recovering and extending hydrological experimental areasin plain areas in the future. Finally, this paper prospected the future development in establishment and research in hydrological experimental areas (catchments) in plain areas. It may be more common to see the cooperation between model scientists and field experts. Because of the comprehensive goals in water problems, researchers from various fields would work together in the future experimental research work. Scale study and modelling in plain areas will be a promising branch after some typical experimental areas

  8. Fundamentos, Orientaciones, Areas Basicas y Procedimientos para la Investigacion Educativa (Bases, Guidelines, Basic Areas, and Procedures for Educational Research).

    Science.gov (United States)

    Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.

    This document establishes the bases, general guidelines, basic areas, and procedures for educational research conducted in Colombia. The philosophy underlying research objectives is explained. There is special interest in social research concerning the condition of man and of the social groups that will be the targets of education, and in research…

  9. Appendix 1—California plant community types represented in Forest Service research natural areas

    Science.gov (United States)

    Sheauchi Cheng

    2004-01-01

    Community types and codes (Holland 1986) are in boldface; research natural area names (with ecological survey names in parentheses, if different from the research natural area names) are in plain type.

  10. Research of morphology and structure of 3C–SiC thin films on silicon by electron microscopy and X-ray diffractometry

    Directory of Open Access Journals (Sweden)

    Alexander S. Gusev

    2015-12-01

    Full Text Available Thin films of silicon carbide possessing unique properties attract increasing attention of researchers both in the field of semiconductor physics and in the technology of new semiconductor devices for high power, RF and optoelectronics. The growth of the production of silicon carbide based devices promotes the search for more resource saving and safe SiC layer synthesis technologies. Potential method is pulse laser deposition (PLD in vacuum. This technology does not require the use of chemically aggressive and explosive gases and allows forming thin and continuous coatings with thicknesses of from several nanometers at relatively low substrate temperatures. Submicron thickness silicon carbide films have been grown on single crystal silicon by vacuum laser ablation of a ceramic target. The physical and technological parameters of silicon carbide thin film low temperature synthesis by PLD have been studied and, in particular, the effect of temperature and substrate crystalline orientation on the composition, structural properties and morphology of the surface of the experimental specimens has been analyzed. At above 500 °C the crystalline β-SiC phase forms on Si (100 and (111. At a substrate temperature of 950 °C the formation of textured heteroepitaxial 3C–SiC films was observed.

  11. Research on area source electron gun in vacuum system

    Science.gov (United States)

    Qiu, Yafeng; Chang, Benkang; Shi, Feng; Qian, Yunsheng; Fu, Rongguo

    High-energy area source electron gun is a key component in image intensifier screen testing instrument. On the basis of the analysis of relationship between thermal emission characteristics, the shape of filament and the density of thermal electron emission, high-energy area source electron gun is designed. The distribution of electric field and electronic tracks are theoretically analyzed and calculated to make it has features of dispersing, uniform, converging and submerging. By testing a standard screen, correct the structure of high-energy area source electron gun to meet the requirements of test indexes and obtain reasonable high-energy area source electron gun. Its successful development provides effective technical support to the luminous screen test for uniformity, brightness, luminescence efficiency and afterglow and to the examination of other components (such as MCP parameters)of Low-light Image Intensifier.

  12. Mapping research areas and collaboration in the College of Human ...

    African Journals Online (AJOL)

    CHS) at the University of South Africa (UNISA) with a view to determining the subjects or topics of research focus as well as the pattern and extent of research collaboration within the college. Using informetric approaches and more specifically the ...

  13. Expanding the research area of behavior change support systems

    NARCIS (Netherlands)

    van Gemert-Pijnen, Julia E.W.C.; Reitberger, Wolfgang; Langrial, Sitwat; Ploderer, Bernd; Oinas-Kukkonen, Harri; Berkovsky, Shlomo; Freyne, Jill

    2013-01-01

    The First International Workshop on Behavior Change Support Systems attracted a great research interest. The selected papers focused on abstraction, implementation and evaluation of Behavior Change Support Systems. The workshop is an evidence of how researchers from around the globe have their own

  14. Research Natural Areas of the Northern Region: Status and Needs Assessment

    Science.gov (United States)

    Steve W. Chadde; Shannon F. Kimball; Angela G. Evenden

    1996-01-01

    A major objective of the Forest Service Research Natural Area (RNA) program is to maintain a representative array of all significant natural ecosystems as baseline areas for research and monitoring (Forest Service Manual 4063, USDA Forest Service 1991). The National Forest Management Act of 1976 directs the agency to establish research natural areas typifying important...

  15. A European Research Area; Un espacio de investigacion Europeo

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.

    2001-07-01

    This article is a summary of the presentation of the European Commissioner, Philippe Busquen, to the European Parliament (beginning of year 2000) with the proposal and method for a revival of the Research and Development in this wider sense in the European Union. The starting point of his thesis is that Europe performs less, and more disorderly, activities in this field that her main competitors. USA and Japan. His basic proposal is a larger coordination among the european research projects, with a previous phase of informatics intoxicator among the european research centres and the cross-linked participation, real of virtual in the experiments and projects. (Author)

  16. Large area multicrystalline silicon solar cells with high efficiency. Final report; Grossflaechige multikristalline Silizium-Solarzellen mit hohen Wirkungsraden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Ebest, G.; Erler, K.; Mrwa, A.; Ball, M.

    2001-09-01

    Solar cells were produced of wafers of die-cast and strip-drawn multicrystalline silicon and characterized. Production methods like SOD (spin-on doping), RTP (rapid thermal processing), PECVD (plasma enhanced chemical vapor deposition), RIE (reactive ion etching) and screen printing were investigated. The results are summarized as follows: 1. Layer resistance can be adjusted by variation of the RTP temperature cycle and by selecting appropriate doping materials (P507 by Filmtronics); 2. The low resistance required for screen printing metallization are obtained only with a different doping material (P8545SF-Filmtronics); 3. Metallized aluminium and copper require a 30 nm TiN layer as diffusion barrier; 4. Reflectivity will be reduced most effectively by RIE with chlorine gas on monocrystalline and multicrystalline silicon wafers. [German] Im Rahmen des Projektes wurden auf Wafern aus blockgegossenem und bandgezogenem multikristallinen Silizium Solarzellen hergestellt und charakterisiert. Fuer die Herstellung wurden Verfahren wie SOD (spin-on doping), RTP (rapid thermal processing), PECVD (plasma enhanced chemical vapor deposition), RIE (reactive ion etching) und Siebdruck untersucht. Die Ergebnisse lassen sich wie folgt zusammenfassen: 1. eine Einstellung des Schichtwiderstandes wird durch Variation des RTP-Temperaturzyklus sowie Auswahl verschiedener Dotierstoffe (P507 von Filmtronics) erreicht; 2. die fuer die Siebdruckmetallisierung erforderlichen geringen Schichtwiderstaende werden nur durch die Wahl eines anderen Dotierstoffes (P8545SF-Filmtronics) erreicht; 3. Aluminium- und Kupfermetallisierungen benoetigen eine 30 nm dicke TiN-Schicht als Diffusionsbarriere; und 4. die wirksamste Verminderung des Reflexionsgrades ist mittels RIE-Verfahren unter Verwendung von Chlorgas auf ein- und multikristalline Siliziumwafer erreichbar.

  17. Ecological research in conserved areas in the Orange Free State ...

    African Journals Online (AJOL)

    There is a need for the protection and scientific management of representative samples of each ecological area of the Orange Free State. Considerable progress has been made with the establishment of a large number of nature reserves by various authorities. Various ecological investigations have been undertaken in ...

  18. Comparison of the outcome of silicone Ahmed glaucoma valve implantation with a surface area between 96 and 184 mm² in adult eyes.

    Science.gov (United States)

    Koh, Kyung Min; Hwang, Young Hoon; Jung, Jong Jin; Sohn, Yong Ho; Kim, Hwang Ki

    2013-10-01

    To compare the success rates, complications, and visual outcomes between silicone Ahmed glaucoma valve (AGV) implantation with 96 mm(2) (FP8) or 184 mm(2) (FP7) surface areas. This study is a retrospective review of the records from 132 adult patients (134 eyes) that underwent silicone AGV implant surgery. Among them, the outcomes of 24 eyes from 24 patients with refractory glaucoma who underwent FP8 AGV implantation were compared with 76 eyes from 76 patients who underwent FP7 AGV implantation. Preoperative and postoperative data, including intraocular pressure (IOP), visual acuity, number of medications, and complications were compared between the 2 groups. There were no significant differences in baseline characteristics between the 2 groups (p > 0.05). The postoperative visual acuity of the patients in the FP8 group was better than that of the patients in the FP7 group in some early postoperative periods (p 0.05). Postoperative IOP was not significantly different between the 2 groups (p > 0.05) except for IOP on postoperative day 1 (11.42 mmHg for the FP7 group and 7.42 mmHg for the FP8 group; p = 0.031). There was no statistical difference in success rates, final IOP, number of medications, or complication rates between the 2 groups (p > 0.05). The FP7 and FP8 AGV implants showed no difference in terms of vision preservation, IOP reduction, and number of glaucoma medications required.

  19. Sorrow and Solace: Neglected Areas in Bereavement Research

    Science.gov (United States)

    Klass, Dennis

    2013-01-01

    The author argues that in its focus on finding positive outcomes, bereavement research has neglected or denigrated central phenomena in intense and long-term grief: sorrow and solace. Sorrow has two elements: yearning for the dead person and grief's depression. Consolation comes into sorrow in human relationships and from inner resources. The…

  20. Research on the structural and electronic properties of defects in amorphous silicon

    Energy Technology Data Exchange (ETDEWEB)

    Street, R.A. (Xerox Palo Alto Research Center, CA (United States))

    1991-12-01

    The work performed for this contract focused on the saturation of light-induced effects, hydrogen-mediated metastability and growth, defects and electronic properties, and remote hydrogen plasma growth. This work included research on hydrogen chemical reactions, hydrogen density-of-states model and metastability, hydrogen bonding configurations, a model for the role of hydrogen complexes in the metastability, and hydrogen chemical potential and growth structure. This document also covers research on thermal generation currents in p-i-n diodes, field dependence of the generation current, metastability effects at contacts, and potential fluctuations in compensated a-Si:H. Information is included on plasma diagnostics using electron spin resonance and nuclear magnetic resonance measurements of remote hydrogen plasma films.

  1. Measurement of neutron spectra in a silicon filtered neutron beam using stilbene detectors at the LVR-15 research reactor.

    Science.gov (United States)

    Košťál, Michal; Šoltés, Jaroslav; Viererbl, Ladislav; Matěj, Zdeněk; Cvachovec, František; Rypar, Vojtěch; Losa, Evžen

    2017-10-01

    A well-defined neutron spectrum is an essential tool for calibration and tests of spectrometry and dosimetry detectors, and evaluation methods for spectra processing. Many of the nowadays used neutron standards are calibrated against a fission spectrum which has a rather smooth energy dependence. In recent time, at the LVR-15 research reactor in Rez, an alternative approach was tested for the needs of fast neutron spectrometry detector calibration. This process comprises detector tests in a neutron beam, filtered by one meter of single-crystalline silicon, which contains several significant peaks in the fast neutron energy range. Tests in such neutron field can possibly reveal specific problems in the deconvolution matrix of the detection system, which may stay hidden in fields with a smooth structure and can provide a tool for a proper energy calibration. Test with several stilbene scintillator crystals in two different beam configurations supplemented by Monte-Carlo transport calculations have been carried out. The results have shown a high level of agreement between the experimental data and simulation, proving thus the accuracy of used deconvolution matrix. The chosen approach can, thus, provide a well-defined neutron reference field with a peaked structure for further tests of spectra evaluation methods and scintillation detector energy calibration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Lithium and sexual dysfunction: an under-researched area.

    Science.gov (United States)

    Elnazer, Hesham Y; Sampson, Anthony; Baldwin, David

    2015-03-01

    Lithium treatment remains an important part of the management of many patients with bipolar disorder, but the incidence of treatment-emergent sexual dysfunction with lithium is uncertain, and little is known about how it might be managed. Systematic computerised literature search of preclinical and clinical studies. Thirteen relevant papers were identified. Preclinical studies suggest lithium can reduce testosterone levels and impair nitric oxide mediated relaxation of cavernosal tissue. Clinical reports suggest lithium may reduce sexual thoughts and desire, worsen erectile function and reduce sexual satisfaction. Concomitant benzodiazepine prescription with lithium is associated with an increased risk of sexual dysfunction. Sexual dysfunction during lithium treatment appears significantly associated with a lower level of overall functioning and may reduce compliance. The findings of this systematic review reveal the paucity of information about the incidence, associated factors and management of sexual dysfunction with lithium treatment and highlight the need for well-designed studies in this area. Copyright © 2015 John Wiley & Sons, Ltd.

  3. FISH & CHIPS: Four Electrode Conductivity / Salinity Sensor on a Silicon Multi-sensor chip for Fisheries Research

    DEFF Research Database (Denmark)

    Hyldgård, Anders; Olafsdottir, Iris; Olesen, M.

    2005-01-01

    The design and fabrication of a single chip silicon salinity, temperature, pressure and light multisensor is presented. The behavior 2- and 4-electrode conductivity microsensors are described and methods for precise determination of water conductivity are given......The design and fabrication of a single chip silicon salinity, temperature, pressure and light multisensor is presented. The behavior 2- and 4-electrode conductivity microsensors are described and methods for precise determination of water conductivity are given...

  4. Porous silicon gettering

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S.; Menna, P.; Pitts, J.R. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    The authors have studied a novel extrinsic gettering method that uses the large surface areas produced by a porous-silicon etch as gettering sites. The annealing step of the gettering used a high-flux solar furnace. They found that a high density of photons during annealing enhanced the impurity diffusion to the gettering sites. The authors used metallurgical-grade Si (MG-Si) prepared by directional solidification casing as the starting material. They propose to use porous-silicon-gettered MG-Si as a low-cost epitaxial substrate for polycrystalline silicon thin-film growth.

  5. 76 FR 63824 - Research Area Within Gray's Reef National Marine Sanctuary

    Science.gov (United States)

    2011-10-14

    ..., ecological, historical, research, educational, or aesthetic value; and the types of activities subject to... proposed research area also may provide opportunities to advance scientific understanding and management of... National Oceanic and Atmospheric Administration 15 CFR Part 922 RIN 0648-AV88 Research Area Within Gray's...

  6. Scenario of research and intellectual production in the area of didactics in the southern of Brazil

    National Research Council Canada - National Science Library

    Orlando Fernández Aquino; Vânia Maria de Oliveira Vieira; Marilene Ribeiro Resende; Maria Célia Borges

    2016-01-01

    The text was drawn from results of research carried out between 2010 and 2012. The objective was to understand the state of research and intellectual production in the area of Didactic in Southern Brazil...

  7. Transformational silicon electronics

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-02-25

    In today\\'s traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 μm), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry\\'s most advanced high-κ/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications. © 2014 American Chemical Society.

  8. Transformational silicon electronics.

    Science.gov (United States)

    Rojas, Jhonathan Prieto; Torres Sevilla, Galo Andres; Ghoneim, Mohamed Tarek; Inayat, Salman Bin; Ahmed, Sally M; Hussain, Aftab Mustansir; Hussain, Muhammad Mustafa

    2014-02-25

    In today's traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 μm), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry's most advanced high-κ/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications.

  9. Porous Silicon Nanowires

    Science.gov (United States)

    Qu, Yongquan; Zhou, Hailong; Duan, Xiangfeng

    2011-01-01

    In this minreview, we summarize recent progress in the synthesis, properties and applications of a new type of one-dimensional nanostructures — single crystalline porous silicon nanowires. The growth of porous silicon nanowires starting from both p- and n-type Si wafers with a variety of dopant concentrations can be achieved through either one-step or two-step reactions. The mechanistic studies indicate the dopant concentration of Si wafers, oxidizer concentration, etching time and temperature can affect the morphology of the as-etched silicon nanowires. The porous silicon nanowires are both optically and electronically active and have been explored for potential applications in diverse areas including photocatalysis, lithium ion battery, gas sensor and drug delivery. PMID:21869999

  10. Silicon applications in photonics

    Science.gov (United States)

    Jelenski, A. M.; Gawlik, G.; Wesolowski, M.

    2005-09-01

    Silicon technology enabled the miniaturization of computers and other electronic system for information storage, transmission and transformation allowing the development of the Knowledge Based Information Society. Despite the fact that silicon roadmap indicates possibilities for further improvement, already now the speed of electrons and the bandwidth of electronic circuits are not sufficient and photons are commonly utilized for signal transmission through optical fibers and purely photonic circuits promise further improvements. However materials used for these purposes II/V semiconductor compounds, glasses make integration of optoelectronic circuits with silicon complex an expensive. Therefore research on light generation, transformation and transmission in silicon is very active and recently, due to nanotechnology some spectacular results were achieved despite the fact that mechanisms of light generation are still discussed. Three topics will be discussed. Porous silicon was actively investigated due to its relatively efficient electroluminescence enabling its use in light sources. Its index of refraction, differs considerably from the index of silicon, and this allows its utilization for Bragg mirrors, wave guides and photonic crystals. The enormous surface enables several applications on medicine and biotechnology and in particular due to the effective chemo-modulation of its refracting index the design of optical chemosensors. An effective luminescence of doped and undoped nanocrystalline silicon opened another way for the construction of silicon light sources. Optical amplification was already discovered opening perspectives for the construction of nanosilicon lasers. Luminescences was observed at red, green and blue wavelengths. The used technology of silica and ion implantation are compatible with commonly used CMOS technology. Finally the recently developed and proved idea of optically pumped silicon Raman lasers, using nonlinearity and vibrations in the

  11. ePIXfab - The silicon photonics platform

    NARCIS (Netherlands)

    Khanna, A.; Drissi, Y.; Dumon, P.; Baets, R.; Absil, P.; Pozo Torres, J.M.; Lo Cascio, D.M.R.; Fournier, M.; Fedeli, J.M.; Fulbert, L.; Zimmermann, L.; Tillack, B.; Aalto, T.; O'Brien, P.; Deptuck, D.; Xu, J.; Gale, D.

    2013-01-01

    ePIXfab-The European Silicon Photonics Support Center continues to provide state-of-the-art silicon photonics solutions to academia and industry for prototyping and research. ePIXfab is a consortium of EU research centers providing diverse expertise in the silicon photonics food chain, from training

  12. FISH & CHIPS: Single Chip Silicon MEMS CTDL Salinity, Temperature, Pressure and Light sensor for use in fisheries research

    DEFF Research Database (Denmark)

    Hyldgård, Anders; Hansen, Ole; Thomsen, Erik Vilain

    2005-01-01

    A single-chip silicon MEMS CTDL multi sensor for use in aqueous environments is presented. The new sensor chip consists of a conductivity sensor based on platinum electrodes (C), an ion-implanted thermistor temperature sensor (T), a piezoresistive pressure sensor (D for depth/pressure) and an ion...

  13. Research publications of the Cascade Head Experimental Forest and Scenic Research Area, Oregon Coast Range, 1934 to 1990.

    Science.gov (United States)

    Sarah E. Greene; Tawny. Blinn

    1991-01-01

    A list of publications resulting from research at the Cascade Head Experimental Forest and Scenic Research Area, Siuslaw National Forest, Oregon, from 1934 to 1990 is presented. Over 200 publications are listed, including papers, theses, and reports. An index is provided that cross-references the listings under appropriate keywords.

  14. Reliability and engineering sciences area. Materials research: Single junction thin film

    Science.gov (United States)

    1986-01-01

    A test bench was designed and fabricated for the purpose of improving control of hot-spot test accuracy. Electrochemical corrosion research focused on corrosion mechanisms to which both crystalline and a-Si modules may be subjected in central station applications. A variety of cells and several designs were subjected to accelerated stress tests. Humiditiy degradation rates were determined and key electrochemical failure mechanisms were identified. Software was developed for the prediction of power loss resulting from open circuits in an array field of a-Si modules. Failure analysis was continued on the four ARCO Solar Genesis modules. The interactions of water on the silicon module was examined. An autocatalytic photooxidation model was proposed. The reliability and durability of bonding materials and electrical insulation were also studied.

  15. Building the European Research Area in nuclear fission pioneering steps in actinide science

    Energy Technology Data Exchange (ETDEWEB)

    Forsstroem, Hans

    2004-07-01

    The concept of the European Research Area (ERA) aims at closer development of research policies in Europe and closer networking of research capacities, to reduce fragmentation of research in Europe. The goal is to make European research more effective and competitive. Several approaches are made to create ERA. The European Research Framework Programme is one tool in this context, with the introduction of the new instruments, Integrated Projects, Networks of Excellence and Integrated Infrastructure Initiatives. Actinide science is one area that could benefit from better coordination and more effective use of the research capacities, both human and physical. The European Commission is thus funding a Network of Excellence (ACTINET-6) and an Integrated Project (EUROPART) in this area within the sixth EURATOM Framework Programme. (author)

  16. High Area Capacity Lithium-Sulfur Full-cell Battery with Prelitiathed Silicon Nanowire-Carbon Anodes for Long Cycling Stability

    Science.gov (United States)

    Krause, Andreas; Dörfler, Susanne; Piwko, Markus; Wisser, Florian M.; Jaumann, Tony; Ahrens, Eike; Giebeler, Lars; Althues, Holger; Schädlich, Stefan; Grothe, Julia; Jeffery, Andrea; Grube, Matthias; Brückner, Jan; Martin, Jan; Eckert, Jürgen; Kaskel, Stefan; Mikolajick, Thomas; Weber, Walter M.

    2016-01-01

    We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm2. The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm2, a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss <0.4% per cycle). A detailed physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging. PMID:27319783

  17. High Area Capacity Lithium-Sulfur Full-cell Battery with Prelitiathed Silicon Nanowire-Carbon Anodes for Long Cycling Stability

    Science.gov (United States)

    Krause, Andreas; Dörfler, Susanne; Piwko, Markus; Wisser, Florian M.; Jaumann, Tony; Ahrens, Eike; Giebeler, Lars; Althues, Holger; Schädlich, Stefan; Grothe, Julia; Jeffery, Andrea; Grube, Matthias; Brückner, Jan; Martin, Jan; Eckert, Jürgen; Kaskel, Stefan; Mikolajick, Thomas; Weber, Walter M.

    2016-06-01

    We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm2. The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm2, a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging.

  18. High Area Capacity Lithium-Sulfur Full-cell Battery with Prelitiathed Silicon Nanowire-Carbon Anodes for Long Cycling Stability.

    Science.gov (United States)

    Krause, Andreas; Dörfler, Susanne; Piwko, Markus; Wisser, Florian M; Jaumann, Tony; Ahrens, Eike; Giebeler, Lars; Althues, Holger; Schädlich, Stefan; Grothe, Julia; Jeffery, Andrea; Grube, Matthias; Brückner, Jan; Martin, Jan; Eckert, Jürgen; Kaskel, Stefan; Mikolajick, Thomas; Weber, Walter M

    2016-06-20

    We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm(2). The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm(2), a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss <0.4% per cycle). A detailed physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging.

  19. Silicon Carbide Growth

    Science.gov (United States)

    2005-01-01

    Andrew Trunek has focused on supporting the Sic team through the growth of Sic crystals, making observations and conducting research that meets the collective needs and requirements of the team while fulfilling program commitments. Cancellation of the Ultra Efficient Engine Technology (UEET) program has had a significant negative impact on resources and research goals. This report highlights advancements and achievements made with this cooperative agreement over the past year. NASA Glenn Research Center (GRC) continues to make advances in silicon carbide (SiC) research during the past year. Step free surfaces were used as substrates for the deposition of GaN epilayers that yielded very low dislocation densities. Defect free 3C- SiC was successfully nucleated on step free mesas and test diodes were fabricated. Web growth techniques were used to increase the usable surface area of dislocation free SiC by approximately equal to 40%. The greatest advancement has been attained on stepped surfaces of SiC. A metrology standard was developed using high temperature etching techniques titled "Nanometer Step Height Standard". This development culminated in being recognized for a 2004 R&D100 award and the process to produce the steps received a NASA Space Act award.

  20. Silicon nano-particles: On Route to a Sustainable Mobility

    OpenAIRE

    Munao, D.

    2012-01-01

    The area of nanotechnology is one of the most active fields in science today. It is often seen as the area that could lead to substantial progress in terms of finding new materials with new properties. In this respect, silicon nano-particles are found to be greatly attractive because of their significant technological implications. Considering different areas of research, the energy production, conversion and storage processes are definitely among the most important topics to be studied by sc...

  1. Silicon Solar Cell Turns 50

    Energy Technology Data Exchange (ETDEWEB)

    Perlin, J.

    2004-08-01

    This short brochure describes a milestone in solar (or photovoltaic, PV) research-namely, the 50th anniversary of the invention of the first viable silicon solar cell by three researchers at Bell Laboratories.

  2. Silicon detector technology development in India for the participation ...

    Indian Academy of Sciences (India)

    Abstract. A specific research and development program has been carried out by BARC in India to develop the technology for large area silicon strip detectors for application in nuclear and high energy physics experiments. These strip detectors will be used as pre-shower detector in the CMS experiment at LHC, CERN for ...

  3. Silicon detector technology development in India for the participation ...

    Indian Academy of Sciences (India)

    A specific research and development program has been carried out by BARC in India to develop the technology for large area silicon strip detectors for application in nuclear and high energy physics experiments. These strip detectors will be used as pre-shower detector in the CMS experiment at LHC, CERN for 0/ ...

  4. The SiNx films process research by plasma-enhanced chemical vapor deposition in crystalline silicon solar cells

    Science.gov (United States)

    Chen, Bitao; Zhang, Yingke; Ouyang, Qiuping; Chen, Fei; Zhan, Xinghua; Gao, Wei

    2017-07-01

    SiNx thin film has been widely used in crystalline silicon solar cell production because of the good anti-reflection and passivation effect. We can effectively optimize the cells performance by plasma-enhanced chemical vapor deposition (PECVD) method to change deposition conditions such as temperature, gas flow ratio, etc. In this paper, we deposit a new layer of SiNx thin film on the basis of double-layers process. By changing the process parameters, the compactness of thin films is improved effectively. The NH3 passivation technology is augmented in a creative way, which improves the minority carrier lifetime. In sight of this, a significant increase is generated in the photoelectric performance of crystalline silicon solar cell.

  5. Euratom research and training in nuclear reactor safety: Towards European research and the higher education area

    Energy Technology Data Exchange (ETDEWEB)

    Goethem, G. van [Nuclear Fission and Radiation Protection European Commission, Building MO75-5-34, B-1049 Brussels (Belgium)]. E-mail: georges.van-goethem@cec.eu.int

    2004-07-01

    In this invited lecture, research and training in nuclear fission are looked at from a European perspective with emphasis on the three success factors of any European policy, namely: common needs, vision and instruments, that ought to be strongly shared amongst the stakeholders across the Member States concerned. As a result, the following questions are addressed: What is driving the current EU trend towards more research, more education and more training, in general? Regarding nuclear fission, in particular, who are the end-users of Euratom 'research and training' and what are their expectations from EU programmes? Do all stakeholders share the same vision about European research and training in nuclear fission? What are the instruments proposed by the European Commission (EC) to conduct joint research programmes of common interest for the nuclear fission community? In conclusion, amongst the stakeholders in Europe, there seems to be a wide consensus about common needs and instruments, but not about a common vision regarding nuclear. (author)

  6. EDITORIAL: Special issue on silicon photonics

    Science.gov (United States)

    Reed, Graham; Paniccia, Mario; Wada, Kazumi; Mashanovich, Goran

    2008-06-01

    The technology now known as silicon photonics can be traced back to the pioneering work of Soref in the mid-1980s (see, for example, Soref R A and Lorenzo J P 1985 Electron. Lett. 21 953). However, the nature of the research conducted today, whilst it builds upon that early work, is unrecognizable in terms of technology metrics such as device efficiency, device data rate and device dimensions, and even in targeted applications areas. Today silicon photonics is still evolving, and is enjoying a period of unprecedented attention in terms of research focus. This has resulted in orders-of-magnitude improvement in device performance over the last few years to levels many thought were impossible. However, despite the existence of the research field for more than two decades, silicon is still regarded as a 'new' optical material, one that is being manipulated and modified to satisfy the requirements of a range of applications. This is somewhat ironic since silicon is one of the best known and most thoroughly studied materials, thanks to the electronics industry that has made silicon its material of choice. The principal reasons for the lack of study of this 'late developer' are that (i) silicon is an indirect bandgap material and (ii) it does not exhibit a linear electro-optic (Pockels) effect. The former condition means that it is difficult to make a laser in silicon based on the intrinsic performance of the material, and consequently, in recent years, researchers have attempted to modify the material to artificially engineer the conditions for lasing to be viable (see, for example, the review text, Jalali B et al 2008 Silicon Lasers in Silicon Photonics: The State of the Art ed G T Reed (New York: Wiley)). The latter condition means that optical modulators are intrinsically less efficient in silicon than in some other materials, particularly when targeting the popular telecommunications wavelengths around 1.55 μm. Therefore researchers have sought alternative

  7. Silicon photonics fundamentals and devices

    CERN Document Server

    Deen, M Jamal

    2012-01-01

    The creation of affordable high speed optical communications using standard semiconductor manufacturing technology is a principal aim of silicon photonics research. This would involve replacing copper connections with optical fibres or waveguides, and electrons with photons. With applications such as telecommunications and information processing, light detection, spectroscopy, holography and robotics, silicon photonics has the potential to revolutionise electronic-only systems. Providing an overview of the physics, technology and device operation of photonic devices using exclusively silicon and related alloys, the book includes: * Basic Properties of Silicon * Quantum Wells, Wires, Dots and Superlattices * Absorption Processes in Semiconductors * Light Emitters in Silicon * Photodetectors , Photodiodes and Phototransistors * Raman Lasers including Raman Scattering * Guided Lightwaves * Planar Waveguide Devices * Fabrication Techniques and Material Systems Silicon Photonics: Fundamentals and Devices outlines ...

  8. Report and Management Plan for Muscatatuck Seep Springs Research Natural Area at Muscatatuck National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report was undertaken to determine the management needs of the threatened and endangered species and the natural community within the Research Natural Area,...

  9. A delineating procedure to retrieve relevant publication data in research areas : the case of nanocellulose

    NARCIS (Netherlands)

    Milanez, D.H.; Noyons, E.C.M.; Lopes, de Faria L.I.

    2016-01-01

    Advances concerning publication-level classification system have been demonstrated striking results by dealing properly with emergent, complex and interdisciplinary research areas, such as nanotechnology and nanocellulose. However, less attention has been paid to propose a delineating method to

  10. Cross-Cultural Communication Training for Students in Multidisciplinary Research Area of Biomedical Engineering

    Directory of Open Access Journals (Sweden)

    Shigehiro Hashimoto

    2014-08-01

    Full Text Available Biomedical Engineering makes multidisciplinary research area, which includes biology, medicine, engineering and others. Communication training is important for students, who have a potential to develop Biomedical Engineering. Communication is not easy in a multidisciplinary research area, because each area has its own background of thinking. Because each nation has its own background of culture, on the other hand, international communication is not easy, either. A cross-cultural student program has been designed for communication training in the multidisciplinary research area. Students from a variety of backgrounds of research area and culture have joined in the program: mechanical engineering, material science, environmental engineering, science of nursing, dentist, pharmacy, electronics, and so on. The program works well for communication training in the multidisciplinary research area of biomedical engineering. Foreign language and digital data give students chance to study several things: how to make communication precisely, how to quote previous data. The experience in the program helps students not only understand new idea in the laboratory visit, but also make a presentation in the international research conference. The program relates to author's several experiences: the student internship abroad, the cross-cultural student camp, multi PhD theses, various affiliations, and the creation of the interdisciplinary department.

  11. Perspectives for food research and European collaboration in the European Research Area and the new Framework Programme.

    Science.gov (United States)

    Breslin, L

    2001-08-01

    Since 1987, successive framework programmes have contributed to strengthen European food research through the establishment of networks between research institutions, universities and companies from various European countries. In the FAIR programme (1994-1998), 118 research projects comprising nearly 1,000 participants from the European Union and Associated States have been supported in the food area with a European funding of about [symbol: see text] 108 million. Within the Quality of Life and Management of Living Resources programme (1998-2002), food research is mostly supported within the key action 'food, nutrition and health' with a budget of [symbol: see text] 290 million. After the first four deadlines, 735 eligible research proposals have already been received. Further to their evaluation by a panel of independent experts, 108 proposals have been funded or selected for funding representing a total contribution of about [symbol: see text] 168 million. Among those, several clusters of projects are now running on important topics such as probiotics, coeliac diseases, mycotoxins, GMO, safety and food for the elderly. In addition, technology stimulation measures are largely benefiting SMEs to foster their innovation potential. In January 2000, the European Commission adopted a Communication entitled "Towards the European Research Area (ERA)" with the objective to contribute to developing better framework conditions for research in Europe. On 21 February 2001, the Commission adopted proposals to be submitted to the European Parliament and Council for the next framework programme for research and innovation (2002-2006). The new framework programme that is becoming one of the financial instruments of the ERA aims at catalysing the integration of European research by: strengthening of links between the Community research effort and national and regional research policies; concentrating on a limited number of priority fields or research to which activities at the

  12. [Financing research in Chile in biotechnology and other areas related to the productive sector].

    Science.gov (United States)

    Gil, L; White, A; Caceres, E

    1990-10-01

    This study describes the financial support for research in Chile in different areas related to the productive sector including biotechnology. Four different sources which help research in the country through competitive research grants were analysed. These include: FONDECYT (National Fund for Research and Technology), Fondo de Desarrollo Productivo de CORFO (Fund for Productive Development), Fondo de Investigaciones Agropecuarias (Fund for Research in Agriculture and Livestock) and the IV Program for Technical Cooperation between the Chilean Government and UNDP. Biotechnology appears as one of the areas related to the productive sector having an important number of projects approved with a substantial financial support. Based in a survey, recommendations are made to improve the relationship between the productive and academic sector in biotechnology and other areas.

  13. PECASE: New Directions for Silicon Integrated Optics

    Science.gov (United States)

    2013-04-30

    silicon microring resonators for label-free biosensing in undiluted human plasma,” Biosensors and Bioelectronics 42 (2013) A widely acknowledged...resonators as high sensitivity biosensors will be discussed. The results of the research including scientific publications and patents are...demonstrating mid-infrared integrated optics in silicon and pursuing new investigations into using silicon resonators as high sensitivity biosensors . A

  14. A review of fatigue in fishermen: a complicated and underprioritised area of research

    DEFF Research Database (Denmark)

    Abrahamsen, Annbjørg; Jensen, Olaf; Holmen, Ingunn

    2014-01-01

    , in order to establish a starting point for further research in this area. Materials and methods: The review is mainly based on journal articles from PubMed, Google Scholar, International Maritime Health, Science Direct and some relevant articles links were also followed. Results: The research revealed...

  15. VEGA: A low-power front-end ASIC for large area multi-linear X-ray silicon drift detectors: Design and experimental characterization

    Science.gov (United States)

    Ahangarianabhari, Mahdi; Macera, Daniele; Bertuccio, Giuseppe; Malcovati, Piero; Grassi, Marco

    2015-01-01

    We present the design and the first experimental characterization of VEGA, an Application Specific Integrated Circuit (ASIC) designed to read out large area monolithic linear Silicon Drift Detectors (SDD's). VEGA consists of an analog and a digital/mixed-signal section to accomplish all the functionalities and specifications required for high resolution X-ray spectroscopy in the energy range between 500 eV and 50 keV. The analog section includes a charge sensitive preamplifier, a shaper with 3-bit digitally selectable shaping times from 1.6 μs to 6.6 μs and a peak stretcher/sample-and-hold stage. The digital/mixed-signal section includes an amplitude discriminator with coarse and fine threshold level setting, a peak discriminator and a logic circuit to fulfill pile-up rejection, signal sampling, trigger generation, channel reset and the preamplifier and discriminators disabling functionalities. A Serial Peripherical Interface (SPI) is integrated in VEGA for loading and storing all configuration parameters in an internal register within few microseconds. The VEGA ASIC has been designed and manufactured in 0.35 μm CMOS mixed-signal technology in single and 32 channel versions with dimensions of 200 μm×500 μm per channel. A minimum intrinsic Equivalent Noise Charge (ENC) of 12 electrons r.m.s. at 3.6 μs peaking time and room temperature is measured and the linearity error is between -0.9% and +0.6% in the whole input energy range. The total power consumption is 481 μW and 420 μW per channel for the single and 32 channels version, respectively. A comparison with other ASICs for X-ray SDD's shows that VEGA has a suitable low noise and offers high functionality as ADC-ready signal processing but at a power consumption that is a factor of four lower than other similar existing ASICs.

  16. Semiconducting silicon nanowires for biomedical applications

    CERN Document Server

    Coffer, JL

    2014-01-01

    Biomedical applications have benefited greatly from the increasing interest and research into semiconducting silicon nanowires. Semiconducting Silicon Nanowires for Biomedical Applications reviews the fabrication, properties, and applications of this emerging material. The book begins by reviewing the basics, as well as the growth, characterization, biocompatibility, and surface modification, of semiconducting silicon nanowires. It goes on to focus on silicon nanowires for tissue engineering and delivery applications, including cellular binding and internalization, orthopedic tissue scaffol

  17. Energy Harvesting from Energetic Porous Silicon

    Science.gov (United States)

    2016-07-01

    wafers backed with platinum are patterned into 2- mm devices with bridge wires (Fig. 1 [left]). Using a silicon nitride layer as a mask, the silicon is...ARL-TR-7719 ● JULY 2016 US Army Research Laboratory Energy Harvesting from Energetic Porous Silicon by Louis B Levine, Matthew...Harvesting from Energetic Porous Silicon by Louis B Levine Academy of Applied Science, Concord, NH Matthew H Ervin and Wayne A Churaman Sensors and

  18. Laser-zone Growth in a Ribbon-to-ribbon (RTR) Process Silicon Sheet Growth Development for the Large Area Silicon Sheet Task of the Low Cost Solar Array Project

    Science.gov (United States)

    Baghdadi, A.; Gurtler, R. W.; Legge, R.; Sopori, B.; Rice, M. J.; Ellis, R. J.

    1979-01-01

    A technique for growing limited-length ribbons continually was demonstrated. This Rigid Edge technique can be used to recrystallize about 95% of the polyribbon feedstock. A major advantage of this method is that only a single, constant length silicon ribbon is handled throughout the entire process sequence; this may be accomplished using cassettes similar to those presently in use for processing Czochralski waters. Thus a transition from Cz to ribbon technology can be smoothly affected. The maximum size being considered, 3 inches x 24 inches, is half a square foot, and will generate 6 watts for 12% efficiency at 1 sun. Silicon dioxide has been demonstrated as an effective, practical diffusion barrier for use during the polyribbon formation.

  19. Mathematics Anxiety and Attitudes of Secondary School Students in Rural Area: A Correlational Research

    Directory of Open Access Journals (Sweden)

    Engin Karadağ

    2014-12-01

    Full Text Available Correlation between mathematics anxiety and attitude of children who are educated in rural areas were analyzed in this research. Research was premeditated as a correlational design because it was presumed that there was correlation between two main variables. The population of the study was consisted of secondary school students who were educated in a region called rural areas in the central district of Meram/Konya in the school year of 2012-2013. 726 students who were educated in five secondary schools comprised of research sample which was designated as stratified sampling method according to educational regions. Research data were collected by the Mathematics Anxiety Scale, and Mathematics Attitude Scale. Correlation and multiple regression analyses were used to examine data. Findings show that correlation between anxiety and attitude of secondary school students from rural area is in negative direction.Key Words:    Rural education, mathematics attitude, mathematics anxiety

  20. The Brazilian research contribution to knowledge of the plant communities from Antarctic ice free areas

    Directory of Open Access Journals (Sweden)

    ANTONIO B. PEREIRA

    2013-09-01

    Full Text Available This work aims to summarize the results of research carried out by Brazilian researchers on the plant communities of Antarctic ice free areas during the last twenty five years. Since 1988 field work has been carried out in Elephant Island, King George Island, Nelson Island and Deception Island. During this period six papers were published on the chemistry of lichens, seven papers on plant taxonomy, five papers on plant biology, two studies on UVB photoprotection, three studies about the relationships between plant communities and bird colonies and eleven papers on plant communities from ice free areas. At the present, Brazilian botanists are researching the plant communities of Antarctic ice free areas in order to understand their relationships to soil microbial communities, the biodiversity, the distribution of the plants populations and their relationship with birds colonies. In addition to these activities, a group of Brazilian researchers are undertaking studies related to Antarctic plant genetic diversity, plant chemistry and their biotechnological applications.

  1. Floating Silicon Method

    Energy Technology Data Exchange (ETDEWEB)

    Kellerman, Peter

    2013-12-21

    The Floating Silicon Method (FSM) project at Applied Materials (formerly Varian Semiconductor Equipment Associates), has been funded, in part, by the DOE under a “Photovoltaic Supply Chain and Cross Cutting Technologies” grant (number DE-EE0000595) for the past four years. The original intent of the project was to develop the FSM process from concept to a commercially viable tool. This new manufacturing equipment would support the photovoltaic industry in following ways: eliminate kerf losses and the consumable costs associated with wafer sawing, allow optimal photovoltaic efficiency by producing high-quality silicon sheets, reduce the cost of assembling photovoltaic modules by creating large-area silicon cells which are free of micro-cracks, and would be a drop-in replacement in existing high efficiency cell production process thereby allowing rapid fan-out into the industry.

  2. DOE Research Set-Aside Areas of the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Davis, C.E.; Janecek, L.L.

    1997-08-31

    Designated as the first of seven National Environmental Research Parks (NERPs) by the Atomic Energy Commission (now the Department of Energy), the Savannah River Site (SRS) is an important ecological component of the Southeastern Mixed Forest Ecoregion located along the Savannah River south of Aiken, South Carolina. Integral to the Savannah River Site NERP are the DOE Research Set-Aside Areas. Scattered across the SRS, these thirty tracts of land have been set aside for ecological research and are protected from public access and most routine Site maintenance and forest management activities. Ranging in size from 8.5 acres (3.44 ha) to 7,364 acres (2,980 ha), the thirty Set-Aside Areas total 14,005 acres (5,668 ha) and comprise approximately 7% of the Site`s total area. This system of Set-Aside Areas originally was established to represent the major plant communities and habitat types indigenous to the SRS (old-fields, sandhills, upland hardwood, mixed pine/hardwood, bottomland forests, swamp forests, Carolina bays, and fresh water streams and impoundments), as well as to preserve habitats for endangered, threatened, or rare plant and animal populations. Many long-term ecological studies are conducted in the Set-Asides, which also serve as control areas in evaluations of the potential impacts of SRS operations on other regions of the Site. The purpose of this document is to give an historical account of the SRS Set-Aside Program and to provide a descriptive profile of each of the Set-Aside Areas. These descriptions include a narrative for each Area, information on the plant communities and soil types found there, lists of sensitive plants and animals documented from each Area, an account of the ecological research conducted in each Area, locator and resource composition maps, and a list of Site-Use permits and publications associated with each Set-Aside.

  3. Printed Large-Area Single-Mode Photonic Crystal Bandedge Surface-Emitting Lasers on Silicon (Open Access Publisher’s Version)

    Science.gov (United States)

    2016-01-04

    Mode Photonic Crystal Bandedge Surface-Emitting Lasers on Silicon Article in Scientific Reports · January 2016 DOI: 10.1038/srep18860 CITATIONS 5 READS...Surface-Emitting Lasers on Silicon Deyin Zhao1,*, Shihchia Liu1,*, Hongjun Yang1, Zhenqiang Ma2, Carl Reuterskiöld-Hedlund3, Mattias Hammar3 & Weidong...Si-PC cavity. Also shown in Fig. 1(a) is the simu- lated optical magnetic H-field distribution profile for the designed lasing cavity mode. In such

  4. 300 Area Integrated Field-Scale Subsurface Research Challenge (IFRC) Field Site Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Freshley, Mark D.

    2008-12-31

    Pacific Northwest National Laboratory (PNNL) has established the 300 Area Integrated Field-Scale Subsurface Research Challenge (300 Area IFRC) on the Hanford Site in southeastern Washington State for the U.S. Department of Energy’s (DOE) Office of Biological and Environmental Research (BER) within the Office of Science. The project is funded by the Environmental Remediation Sciences Division (ERSD). The purpose of the project is to conduct research at the 300 IFRC to investigate multi-scale mass transfer processes associated with a subsurface uranium plume impacting both the vadose zone and groundwater. The management approach for the 300 Area IFRC requires that a Field Site Management Plan be developed. This is an update of the plan to reflect the installation of the well network and other changes.

  5. Methods for structuring scientific knowledge from many areas related to aging research.

    Science.gov (United States)

    Zhavoronkov, Alex; Cantor, Charles R

    2011-01-01

    Aging and age-related disease represents a substantial quantity of current natural, social and behavioral science research efforts. Presently, no centralized system exists for tracking aging research projects across numerous research disciplines. The multidisciplinary nature of this research complicates the understanding of underlying project categories, the establishment of project relations, and the development of a unified project classification scheme. We have developed a highly visual database, the International Aging Research Portfolio (IARP), available at AgingPortfolio.org to address this issue. The database integrates information on research grants, peer-reviewed publications, and issued patent applications from multiple sources. Additionally, the database uses flexible project classification mechanisms and tools for analyzing project associations and trends. This system enables scientists to search the centralized project database, to classify and categorize aging projects, and to analyze the funding aspects across multiple research disciplines. The IARP is designed to provide improved allocation and prioritization of scarce research funding, to reduce project overlap and improve scientific collaboration thereby accelerating scientific and medical progress in a rapidly growing area of research. Grant applications often precede publications and some grants do not result in publications, thus, this system provides utility to investigate an earlier and broader view on research activity in many research disciplines. This project is a first attempt to provide a centralized database system for research grants and to categorize aging research projects into multiple subcategories utilizing both advanced machine algorithms and a hierarchical environment for scientific collaboration.

  6. Methods for structuring scientific knowledge from many areas related to aging research.

    Directory of Open Access Journals (Sweden)

    Alex Zhavoronkov

    Full Text Available Aging and age-related disease represents a substantial quantity of current natural, social and behavioral science research efforts. Presently, no centralized system exists for tracking aging research projects across numerous research disciplines. The multidisciplinary nature of this research complicates the understanding of underlying project categories, the establishment of project relations, and the development of a unified project classification scheme. We have developed a highly visual database, the International Aging Research Portfolio (IARP, available at AgingPortfolio.org to address this issue. The database integrates information on research grants, peer-reviewed publications, and issued patent applications from multiple sources. Additionally, the database uses flexible project classification mechanisms and tools for analyzing project associations and trends. This system enables scientists to search the centralized project database, to classify and categorize aging projects, and to analyze the funding aspects across multiple research disciplines. The IARP is designed to provide improved allocation and prioritization of scarce research funding, to reduce project overlap and improve scientific collaboration thereby accelerating scientific and medical progress in a rapidly growing area of research. Grant applications often precede publications and some grants do not result in publications, thus, this system provides utility to investigate an earlier and broader view on research activity in many research disciplines. This project is a first attempt to provide a centralized database system for research grants and to categorize aging research projects into multiple subcategories utilizing both advanced machine algorithms and a hierarchical environment for scientific collaboration.

  7. How are topics born? Understanding the research dynamics preceding the emergence of new areas

    Directory of Open Access Journals (Sweden)

    Angelo A. Salatino

    2017-06-01

    Full Text Available The ability to promptly recognise new research trends is strategic for many stakeholders, including universities, institutional funding bodies, academic publishers and companies. While the literature describes several approaches which aim to identify the emergence of new research topics early in their lifecycle, these rely on the assumption that the topic in question is already associated with a number of publications and consistently referred to by a community of researchers. Hence, detecting the emergence of a new research area at an embryonic stage, i.e., before the topic has been consistently labelled by a community of researchers and associated with a number of publications, is still an open challenge. In this paper, we begin to address this challenge by performing a study of the dynamics preceding the creation of new topics. This study indicates that the emergence of a new topic is anticipated by a significant increase in the pace of collaboration between relevant research areas, which can be seen as the ‘parents’ of the new topic. These initial findings (i confirm our hypothesis that it is possible in principle to detect the emergence of a new topic at the embryonic stage, (ii provide new empirical evidence supporting relevant theories in Philosophy of Science, and also (iii suggest that new topics tend to emerge in an environment in which weakly interconnected research areas begin to cross-fertilise.

  8. Integrated Silicon Optoelectronics

    CERN Document Server

    Zimmermann, Horst K

    2010-01-01

    Integrated Silicon Optoelectronics synthesizes topics from optoelectronics and microelectronics. The book concentrates on silicon as the major base of modern semiconductor devices and circuits. Starting from the basics of optical emission and absorption, as well as from the device physics of photodetectors, the aspects of the integration of photodetectors in modern bipolar, CMOS, and BiCMOS technologies are discussed. Detailed descriptions of fabrication technologies and applications of optoelectronic integrated circuits are included. The book, furthermore, contains a review of the newest state of research on eagerly anticipated silicon light emitters. In order to cover the topics comprehensively, also included are integrated waveguides, gratings, and optoelectronic power devices. Numerous elaborate illustrations facilitate and enhance comprehension. This extended edition will be of value to engineers, physicists, and scientists in industry and at universities. The book is also recommended to graduate student...

  9. Uniformity and passivation research of Al2O3 film on silicon substrate prepared by plasma-enhanced atom layer deposition.

    Science.gov (United States)

    Jia, Endong; Zhou, Chunlan; Wang, Wenjing

    2015-01-01

    Plasma-enhanced atom layer deposition (PEALD) can deposit denser films than those prepared by thermal ALD. But the improvement on thickness uniformity and the decrease of defect density of the films deposited by PEALD need further research. A PEALD process from trimethyl-aluminum (TMA) and oxygen plasma was investigated to study the influence of the conditions with different plasma powers and deposition temperatures on uniformity and growth rate. The thickness and refractive index of films were measured by ellipsometry, and the passivation effect of alumina on n-type silicon before and after annealing was measured by microwave photoconductivity decay method. Also, the effects of deposition temperature and annealing temperature on effective minority carrier lifetime were investigated. Capacitance-voltage and conductance-voltage measurements were used to investigate the interface defect density of state (D it) of Al2O3/Si. Finally, Al diffusion P(+) emitter on n-type silicon was passivated by PEALD Al2O3 films. The conclusion is that the condition of lower substrate temperature accelerates the growth of films and that the condition of lower plasma power controls the films' uniformity. The annealing temperature is higher for samples prepared at lower substrate temperature in order to get the better surface passivation effects. Heavier doping concentration of Al increased passivation quality after annealing by the effective minority carrier lifetime up to 100 μs.

  10. Critical discourse analysis: new possibilities for scientific research in the mental health area.

    Science.gov (United States)

    de Pinho, Leandro Barbosa; Kantorski, Luciane Prado; Bañon Hernández, Antonio Miguel

    2009-01-01

    The present study aims to get to know the philosophical, conceptual and methodological aspects of Critical Discourse Analysis, as a theoretical-methodological framework for research in the mental health area. Initially, the study presents a reflection on psychiatric discourse in history and at present, with the goal of introducing concepts and presuppositions that would guide the analysis of discursive processes. Discussions are presented about the historical milestones of Critical Discourse Analysis as an analytical framework in social sciences. Finally, the study presents its conceptual and methodological applications to research in the mental health area.

  11. Selective emitter using porous silicon for crystalline silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Inyong; Kim, Kyunghae; Kim, Youngkuk; Han, Kyumin; Kyeong, Doheon; Kwon, Taeyoung; Vinh Ai, Dao; Lee, Jeongchul; Yi, Junsin [School of Information and Communication Engineering, Sungkyunkwan University, Chunchun-dong, Jangan-Gu, Suwon-City, Kyunggi-Do 440-746 (Korea); Thamilselvan, M. [School of Information and Communication Engineering, Sungkyunkwan University, Chunchun-dong, Jangan-Gu, Suwon-City, Kyunggi-Do 440-746 (Korea); Government College of Technology, Coimbatore, Tamilnadu (India); Ju, Minkyu; Lee, Kyungsoo [KPE Ins. Chunchun-dong, Jangan-Gu, Suwon-City, Kyunggi-Do 440-746 (Korea)

    2009-06-15

    This study is devoted to the formation of high-low-level-doped selective emitter for crystalline silicon solar cells for photovoltaic application. We report here the formation of porous silicon under chemical reaction condition. The chemical mixture containing hydrofluoric and nitric acid, with de-ionized water, was used to make porous on the half of the silicon surface of size 125 x 125 cm. Porous and non-porous areas each share half of the whole silicon surface. H{sub 3}PO{sub 4}:methanol gives the best deposited layer with acceptable adherence and uniformity on the non-porous and porous areas of the silicon surface to get high- and low-level-doped regions. The volume concentration of H{sub 3}PO{sub 4} does not exceed 10% of the total volume emulsion. Phosphoric acid was used as an n-type doping source to make emitter for silicon solar cells. The measured emitter sheet resistances at the high- and low-level-doped regions were 30-35 and 97-474 {omega}/{open_square} respectively. A simple process for low- and high-level doping has been achieved by forming porous and porous-free silicon surface, in this study, which could be applied for solar cells selective emitter doping. (author)

  12. Research on silicon-carbon alloys and interfaces. Final subcontract report, 15 February 1991--31 July 1994

    Energy Technology Data Exchange (ETDEWEB)

    Abelson, J.R. [Illinois Univ., Urbana, IL (United States)

    1995-07-01

    This report describes work performed to develop improved p-type wide-band-gap hydrogenated amorphous silicon-carbon alloy (a-Si{sub 1-x}C{sub x:}H) thin films and interfaces for the ``top junction`` in hydrogenated amorphous silicon (a-Si:H)-based p-i-n solar cells. We used direct current reactive magnetron sputtering to deposit undoped a-Si{sub 1-x}C{sub x}H films with a Tauc band gap E{sub g} of 1.90 eV, a sub-band-gap absorption of 0.4 (at 1.2 eV), an Urbach energy of 55 MeV, an ambipolar diffusion length of 100 nm, an air-mass-one photoconductivity of 10{sup {minus}6}/{Omega}-cm, and a dark conductivity of 8{times} 1O{sup {minus}11}/{Omega}-cm. p{sup +}a-Si{sub 1-x}C{sub x}:H films with a Tauc band gap of 1.85 eV have a dark conductivity of 8 {times} 10{sup {minus}6}/{Omega}-cm and thermal activation energy of 0.28 eV. We used in-situ spectroscopic ellipsometry and post-growth X-ray photoelectron spectroscopy to determine the relative roles of H and Si in the chemical reduction of SnO{sub 2} in the early stages of film growth. We used in-situ spectroscopic ellipsometry to show that a-Si:H can be transformed into {mu}c-Si:H in a subsurface region under appropriate growth conditions. We also determined substrate cleaning and ion bombardment conditions which improve the adhesion of a-Si{sub 1-x}C{sub x}:H films.

  13. RESEARCH ON THE HOMOGENEITY OF TEMPERATURES IN JOINT'S AREA BY VULCANIZING THE CONVEYOR BELTS

    OpenAIRE

    Dan DOBROTA

    2016-01-01

    The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points c...

  14. Prospective areas in the production technology of scientific equipment for space research

    Science.gov (United States)

    Breslavets, A. V.

    1974-01-01

    The average labor of individual types of operations in the percentage ratio of the total labor consumption of manufacturing scientific instruments and apparatus for space research is presented. The prospective areas in the production technology of billet, machining, mechanical assembly, installation and assembly, adjustment and regulation and testing and control operations are noted. Basic recommendations are made with respect to further reduction of labor consumption and an increase in the productivity of labor when manufacturing scientific equipment for space research.

  15. Scenario of research and intellectual production in the area of didactics in the southern of Brazil

    Directory of Open Access Journals (Sweden)

    Orlando Fernández Aquino

    2016-01-01

    Full Text Available The text was drawn from results of research carried out between 2010 and 2012. The objective was to understand the state of research and intellectual production in the area of Didactic in Southern Brazil. The documentary analysis methodology, working with documents available online was applied. The research was carried out with 9 Postgraduate Program in Education, 12 research lines, 115 professors, 244 research projects and 1730 publications. It was concluded that there is a great number of research and publication on the investigative field of Didactics and on the dimension of its foundation, but very little on the disciplinary and professional fields and on the conditions and ways of teaching. It is noteworthy that only a transformative practice can help change the reality of the school, the quality of teacher formation, of learning and mental development of the students.

  16. Aquaporins Mediate Silicon Transport in Humans.

    Science.gov (United States)

    Garneau, Alexandre P; Carpentier, Gabriel A; Marcoux, Andrée-Anne; Frenette-Cotton, Rachelle; Simard, Charles F; Rémus-Borel, Wilfried; Caron, Luc; Jacob-Wagner, Mariève; Noël, Micheline; Powell, Jonathan J; Bélanger, Richard; Côté, François; Isenring, Paul

    2015-01-01

    In animals, silicon is an abundant and differentially distributed trace element that is believed to play important biological functions. One would thus expect silicon concentrations in body fluids to be regulated by silicon transporters at the surface of many cell types. Curiously, however, and even though they exist in plants and algae, no such transporters have been identified to date in vertebrates. Here, we show for the first time that the human aquaglyceroporins, i.e., AQP3, AQP7, AQP9 and AQP10 can act as silicon transporters in both Xenopus laevis oocytes and HEK-293 cells. In particular, heterologously expressed AQP7, AQP9 and AQP10 are all able to induce robust, saturable, phloretin-sensitive silicon transport activity in the range that was observed for low silicon rice 1 (lsi1), a silicon transporter in plant. Furthermore, we show that the aquaglyceroporins appear as relevant silicon permeation pathways in both mice and humans based on 1) the kinetics of substrate transport, 2) their presence in tissues where silicon is presumed to play key roles and 3) their transcriptional responses to changes in dietary silicon. Taken together, our data provide new evidence that silicon is a potentially important biological element in animals and that its body distribution is regulated. They should open up original areas of investigations aimed at deciphering the true physiological role of silicon in vertebrates.

  17. Aquaporins Mediate Silicon Transport in Humans.

    Directory of Open Access Journals (Sweden)

    Alexandre P Garneau

    Full Text Available In animals, silicon is an abundant and differentially distributed trace element that is believed to play important biological functions. One would thus expect silicon concentrations in body fluids to be regulated by silicon transporters at the surface of many cell types. Curiously, however, and even though they exist in plants and algae, no such transporters have been identified to date in vertebrates. Here, we show for the first time that the human aquaglyceroporins, i.e., AQP3, AQP7, AQP9 and AQP10 can act as silicon transporters in both Xenopus laevis oocytes and HEK-293 cells. In particular, heterologously expressed AQP7, AQP9 and AQP10 are all able to induce robust, saturable, phloretin-sensitive silicon transport activity in the range that was observed for low silicon rice 1 (lsi1, a silicon transporter in plant. Furthermore, we show that the aquaglyceroporins appear as relevant silicon permeation pathways in both mice and humans based on 1 the kinetics of substrate transport, 2 their presence in tissues where silicon is presumed to play key roles and 3 their transcriptional responses to changes in dietary silicon. Taken together, our data provide new evidence that silicon is a potentially important biological element in animals and that its body distribution is regulated. They should open up original areas of investigations aimed at deciphering the true physiological role of silicon in vertebrates.

  18. Laser-zone growth in a Ribbon-to-Ribbon (RTR) process, silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Technical quarterly report No. 6, October 10--December 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Gurtler, R W; Baghdadi, A; Legge, R; Sopori, B; Ellis, R J

    1977-01-01

    The objective of this research is to fully investigate the Ribbon-to-Ribbon (RTR) approach to silicon ribbon growth. An existing RTR apparatus is to be upgraded to its full capabilities and operated routinely to investigate and optimize the effects of various growth parameters on growth results. A new RTR apparatus is to be constructed to incorporate increased capabilities and improvements over the first apparatus and to be capable of continuous growth. Material analyses and solar cell fabrication process optimization are to be performed with a goal of 12% cell efficiency. During this quarter the laser lab was relocated and operation resumed. New high power lasers have been implemented and this has led to major improvements in growth velocity--4''/min. growth has been demonstrated. This high growth capability has been accompanied, however, with the appearance of dendritic growth. A major step in demonstration of the full feasibility of the RTR process is reported in the demonstration of RTR growth from CVD polyribbon rather than selected polyribbon ingots. Cell and material evaluations have continued. Average solar cell efficiencies of >9% and a best cell efficiency of 11.7% are reported. Processing has been shown to provide a substantial improvement in material minority carrier diffusion length. An economic analysis is reported which treats both the polyribbon fabrication and RTR processes. Indications are that the long term DOE goals may be met.

  19. Research on the Value of AACSB Business Accreditation in Selected Areas: A Review and Synthesis

    Science.gov (United States)

    Hunt, Steven C.

    2015-01-01

    The AACSB claims that its accreditation provides evidence of business school quality in a variety of areas. This paper reviews and synthesizes existing research on the value of AACSB accreditation on four key topics of importance to schools, prospective students, and employers: effect on obtaining quality students, students' job placement, faculty…

  20. Restoration of native plant communities infested by invasive weeds -- Sawmill Creek Research Natural Area

    Science.gov (United States)

    Peter Rice

    2000-01-01

    Invasive alien weeds established themselves on the Sawmill Creek Research Natural Area, harming elk feeding grounds and threatening the integrity of the native plant community. Management enacted herbicide control over several growing seasons, resulting in greater elk winter forage on study plots. Monitoring the long-term effects of herbicide as a restoration tool...

  1. 40 CFR 230.54 - Parks, national and historical monuments, national seashores, wilderness areas, research sites...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Parks, national and historical monuments, national seashores, wilderness areas, research sites, and similar preserves. 230.54 Section 230... Human Use Characteristics § 230.54 Parks, national and historical monuments, national seashores...

  2. Engineering Research and Development and Technology thrust area report FY92

    Energy Technology Data Exchange (ETDEWEB)

    Langland, R.T.; Minichino, C. [eds.

    1993-03-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the technical staff and the technology needed to support current and future LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) to identify key technologies and (2) to conduct high-quality work to enhance our capabilities in these key technologies. To help focus our efforts, we identify technology thrust areas and select technical leaders for each area. The thrust areas are integrated engineering activities and, rather than being based on individual disciplines, they are staffed by personnel from Electronics Engineering, Mechanical Engineering, and other LLNL organizations, as appropriate. The thrust area leaders are expected to establish strong links to LLNL program leaders and to industry; to use outside and inside experts to review the quality and direction of the work; to use university contacts to supplement and complement their efforts; and to be certain that we are not duplicating the work of others. This annual report, organized by thrust area, describes activities conducted within the Program for the fiscal year 1992. Its intent is to provide timely summaries of objectives, theories, methods, and results. The nine thrust areas for this fiscal year are: Computational Electronics and Electromagnetics; Computational Mechanics; Diagnostics and Microelectronics; Emerging Technologies; Fabrication Technology; Materials Science and Engineering; Microwave and Pulsed Power; Nondestructive Evaluation; and Remote Sensing and Imaging, and Signal Engineering.

  3. Awareness Research Concerning the Existence and Implications of the Avrig – Scorei – Fagaras protected Area

    Directory of Open Access Journals (Sweden)

    Bratucu G.

    2014-12-01

    Full Text Available This article is based upon a survey conducted in the protected area of Avrig - Scorei - Făgăraş from Romania. The main purpose of the article is to determine the awareness, attitudes and ways in which the inhabitants of a protected area may act towards the conservation of the area and support the community development. The research was based on a direct interview, using a questionnaire comprising 20 direct questions. The sampling method was probabilistic, with a multistage sampling, as it allows the possibility to extrapolate the results obtained for the entire research population. The systematic error is of +/-4%. The results showed a reduced awareness of the residents about the existence, functioning and support of this protected area, as well as a positive approach of the local public institutions involved in the management of the area. The local institutions have started to enforce the rules and regulations concerning the protection of the environment in this area, still with a long way to run, according to the opinions of the locals, until reaching the EU standards in this field.

  4. ASSESSMENT FORM - NEW IMPROVEMENT OF ACTIONS: CONCENTRATION AND RESEARCH AREAS / CURRICULUM STRUCTURE / FUNDRAISING

    Directory of Open Access Journals (Sweden)

    Iracema MP Calderon

    Full Text Available Objective: This review aims to develop a critical and current analysis of the basic structure of a Postgraduate program for proposing improvement actions and new evaluation criteria. Method: To examine the items that are areas of concentration (AC, research lines (LP, research projects (PP, curricular structure and fundraising were consulted the Area Document, the 2013 Evaluation Report and the Assessment Sheets of Medicine III programs, evaluated in the 2010-2012 period. Results: Consistency is recommended especially among AC, LP and PP, with genuine link between activities and permanent teachers skills and based on structured curriculum in the education of the student. The Program Proposal interfere, and much, in qualifying a program. The curriculum should provide subsidy to the formation of the researcher, through the core subjects, and development of PP, being the concept of disciplines to support lines and research projects. Fundraise should be set out in research projects and in the CV-Lattes. The area recommended that at least 40-50% of permanent teachers present fundraising and the minimum 20-25% of these teachers to have productivity scholarship PQ / CNPq during the triennium. Conclusion: It is necessary to promote wide discussion and find a consensus denominator for these issues. The actions should contribute to the improvement of evaluation forms and certainly for the qualification of the programs but graduate.

  5. The Moquah Barrens Research Natural Area: Loss of a pine barrens ecosystem

    Science.gov (United States)

    Ribic, Christine

    2017-01-01

    The Moquah Barrens Research Natural Area (RNA) was established by the Chequamegon National Forest and the Lakes States Forest Experiment Station in 1935 with a research objective well-suited to the needs of the Forest Service and the scientific understanding of ecosystem function prevalent at the time of establishment. The original research plan was never implemented, which led to a joint Forest-Station decision in 1956 to disestablish the RNA. However, that decision was never implemented. A series of management decisions made after 1956 led to the loss of the pine barrens ecosystem originally encompassed by the RNA. This loss is not irretrievable and the work necessary to recover the original ecosystem is possible under existing RNA management guidelines. The experience of the Moquah Barrens RNA can be used by the Forest Service to improve overall management of the entire system of research natural areas. Two main areas of opportunity are identified: 1) implement an improved approach to managing official records associated with RNAs; and 2) adopt a management framework suitable for long-term ecological projects.

  6. Biological variability in human body composition : implication in the rules and methodology research areas

    OpenAIRE

    Silva, Analiza Mónica Lopes de Almeida

    2005-01-01

    Doutoramento em Motricidade Humana na especialidade de Saúde e Condição Física This thesis presents five investigations related to the body composition rules and methodology research areas. In the rules, newly developed methods such as in vivo neutron activation analysis are used as the reference to evaluate the assumption of the stable mineral-to-protein density in Siri's three-compartment model for estimating total-body-fat mass. In the methodology area, the assessment of extracellular w...

  7. Development of a Test System for the Quality Assurance of Silicon Microstrip Detectors for the Inner Tracking System of the CMS Experiment

    CERN Document Server

    Axer, Markus

    2003-01-01

    The inner tracking system of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) which is being built at the European Laboratory for Particle Physics CERN (Geneva, Switzerland) will be equipped with two different technologies of silicon detectors. While the innermost tracker will be composed of silicon pixel detectors, silicon microstrip detectors are envisaged for the outer tracker architecture. The silicon microstrip tracker will house about 15,000 single detector modules each composed of a set of silicon sensors, the readout electronics (front end hybrid), and a support frame. It will provide a total active area of 198 m2 and ten million analogue channels read out at the collider frequency of 40 MHz. This large number of modules to be produced and integrated into the tracking system is an unprecedented challenge involving industrial companies and various research institutes from many different countries. This thesis deals with the physics of silicon sensors and the preparation of ...

  8. The influence of initial defects on mechanical stress and deformation distribution in oxidized silicon

    Directory of Open Access Journals (Sweden)

    Kulinich O. A.

    2008-10-01

    Full Text Available The near-surface silicon layers in silicon – dioxide silicon systems with modern methods of research are investigated. It is shown that these layers have compound structure and their parameters depend on oxidation and initial silicon parameters. It is shown the influence of initial defects on mechanical stress and deformation distribution in oxidized silicon.

  9. Recent advances in the source term area within the SARNET European severe accident research network

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, L.E., E-mail: luisen.herranz@ciemat.es [Centro de Investigaciones Energeticas Medio Ambientales y Tecnologica, CIEMAT, Avda. Complutense 40, E-28040 Madrid (Spain); Haste, T. [Institut de Radioprotection et de Sûreté Nucléaire, IRSN, BP 3, F-13115 St Paul lez Durance Cedex (France); Kärkelä, T. [VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT Espoo (Finland)

    2015-07-15

    Highlights: • Main achievements of source term research in SARNET are given. • Emphasis on the radiologically important iodine and ruthenium fission products. • Conclusions on FP release, transport in the RCS and containment behaviour. • Significance of large-scale integral experiments to validate the analyses used. • A thorough list of the most recent references on source term research results. - Abstract: Source Term has been one of the main research areas addressed within the SARNET network during the 7th EC Framework Programme of EURATOM. The entire source term domain was split into three major areas: oxidising impact on source term, iodine chemistry in the reactor coolant system and containment and data and code assessment. The present paper synthesises the main technical outcome stemming from the SARNET FWP7 project in the area of source term and includes an extensive list of references in which deeper insights on specific issues may be found. Besides, based on the analysis of the current state of the art, an outlook of future source term research is outlined, where major changes in research environment are discussed (i.e., the end of the Phébus FP project; the end of the SARNET projects; and the launch of HORIZON 2020). Most probably research projects will be streamlined towards: release and transport under oxidising conditions, containment chemistry, existing and innovative filtered venting systems and others. These will be in addition to a number of projects that have been completed or are ongoing under different national and international frameworks, like VERDON, CHIP and EPICUR started under the International Source Term Programme (ISTP), the OECD/CSNI programmes BIP, BIP2, STEM, THAI and THAI2, and the French national programme MIRE. The experimental PASSAM project under the 7th EC Framework programme, focused on source term mitigation systems, is highlighted as a good example of a project addressing potential enhancement of safety systems

  10. Scattering characteristics from porous silicon

    Directory of Open Access Journals (Sweden)

    R. Sabet-Dariani

    2000-12-01

    Full Text Available   Porous silicon (PS layers come into existance as a result of electrochemical anodization on silicon. Although a great deal of research has been done on the formation and optical properties of this material, the exact mechanism involved is not well-understood yet.   In this article, first, the optical properties of silicon and porous silicon are described. Then, previous research and the proposed models about reflection from PS and the origin of its photoluminescence are reveiwed. The reflecting and scattering, absorption and transmission of light from this material, are then investigated. These experiments include,different methods of PS sample preparation their photoluminescence, reflecting and scattering of light determining different characteristics with respect to Si bulk.

  11. RESEARCH ON THE HOMOGENEITY OF TEMPERATURES IN JOINT'S AREA BY VULCANIZING THE CONVEYOR BELTS

    Directory of Open Access Journals (Sweden)

    Dan DOBROTA

    2016-05-01

    Full Text Available The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points corresponding to each end of the two conveyor belts on the both sides of the band, namely the active and inactive side.

  12. Development of Radiation Hard Radiation Detectors, Differences between Czochralski Silicon and Float Zone Silicon

    CERN Document Server

    Tuominen, Eija

    2012-01-01

    The purpose of this work was to develop radiation hard silicon detectors. Radiation detectors made ofsilicon are cost effective and have excellent position resolution. Therefore, they are widely used fortrack finding and particle analysis in large high-energy physics experiments. Silicon detectors willalso be used in the CMS (Compact Muon Solenoid) experiment that is being built at the LHC (LargeHadron Collider) accelerator at CERN (European Organisation for Nuclear Research). This work wasdone in the CMS programme of Helsinki Institute of Physics (HIP).Exposure of the silicon material to particle radiation causes irreversible defects that deteriorate theperformance of the silicon detectors. In HIP CMS Programme, our approach was to improve theradiation hardness of the silicon material with increased oxygen concentration in silicon material. Westudied two different methods: diffusion oxygenation of Float Zone silicon and use of high resistivityCzochralski silicon.We processed, characterised, tested in a parti...

  13. History of research of the Eneolithic sites of the Ik and Belaya Rivers interfluve area

    Directory of Open Access Journals (Sweden)

    Shipilov Anton V.

    2014-12-01

    Full Text Available The history of research of the Eneolithic Age archaeological resources in the Ik and Belaya rivers interfluve area is considered. Most attention is paid to source base formation, field investigation methods development, and modifications in the approaches to historical interpretation of the Eneolithic archaeological sources that are reflected in varied terminology. The basic concepts referring to the origin, formation and development of the Eneolithic archaeological cultures and cultural communities in the Ik and Belaya rivers interfluve area that were put forward in the second half of the 20th century by O.N. Bader, A.Kh. Khalikov, R.S. Gabyashev, L.A. Nagovitsyn, A.A. Vybornov and other researchers of the prehistoric period in the Kama region are analyzed in the article.

  14. International adoption of children with birth defects: current knowledge and areas for further research.

    Science.gov (United States)

    Cochran, Meagan E; Nelson, Katherine R; Robin, Nathaniel H

    2014-12-01

    To summarize the existing literature on the international adoption of children with birth defects and identify areas for further research. International adoption brings thousands of children to the United States each year, and children with birth defects are overrepresented in this population. Studies have demonstrated disparities in the health of children adopted from different countries as well as the complexity of medical care needed after adoption. Although the health of children involved in international adoption has been well studied, there is a lack of information about the experiences of the adoptive parents of children with birth defects. We discuss a pilot study conducted on adoptive parents of children with a specific birth defect, orofacial clefting, and discuss areas for future research.

  15. Research on the Identity Construction of the Disabled Elderly in Rural Areas of China

    Directory of Open Access Journals (Sweden)

    Xu Chen

    2014-04-01

    Full Text Available The identity construction is a very important aspect among the problems of the disabled elderly in rural areas of China. Based on the method of case study and theoretical analysis, this research studies the contents and the process of the identity construction of the disabled elderly in rural areas. It suggests that the identity consists of three elements: personal identity, group identity and social identity, and the characteristics of which include the “high recognition on the disability”, the “core construction of the disability”, the “daily expenses orientation” and the “de-certification of the identity construction”. The mechanism of the construction is supported by three different system types: the basic system, the consolidation system and the maintenance system. The results of the construction demonstrate the features of the identity of “triple-weakness” and “muddling along” of the disabled elderly in rural areas.

  16. Comparative Research on Human Settlements in Asian Rural Areas Based on Collaborative Construction Mechanism

    Science.gov (United States)

    Xin, Sui; Chaoyang, Sun; Mo, Li

    2018-02-01

    Rural planning is perceived as a spatial planning centered on the human settlements and there are many activities for rural reconstruction and researches conducted from the perspective of active intervention, with fewer studies regarding the village as the main body for the establishment of self-built system. And the other-organization built by the rural areas is strongly oriented. In Asian countries like China, South Korea and Japan, there are farming traditions, in which the familial and small-scale farmland holding and agricultural production mode are deep-rooted. Traditional agriculture and rural areas are not fundamentally changed by industrialization and modernization process. And the small-scale peasant in the East is marked by the decentralized possession of farmland and management in the rural areas and a large number of farmers to be remained. But the rural population keeps decreasing. After analyzing the status quo of human settlements in China, Korea and Japan, the paper makes an analysis from the different ways of thinking and professional perspective and focuses on putting forward the solutions to the problems on macro level, with the feasibility of the practical significance and the landing researches still staying in the testing stage. In the context of increasingly missing regional and contextual features, the launching and researches of “co-constructed community” as the folk protection way to emerging rural heritage are just started, and the researches on rural construction in Northeast China from the perspective of catalyst are absent. The contact agent with the catalytic action mechanism of seeing big things through small ones fits the rural areas marked by vast territory and diversified aspect, which is applicable to the bottom-up operation mechanism autonomously built by the villagers.

  17. Measuring International Technology Spillovers and Progress Towards the European Research Area

    OpenAIRE

    SIEDSCHLAG, IULIA

    2009-01-01

    The objective of this paper is to contribute to the development of an evidence-based system to monitor progress towards the European Research Area (ERA) and a knowledge-based economy. We start with an overview of existing theory and empirical evidence on the role of international technology spillovers on economic growth. Further, we discuss the transmission channels of international technology spillovers and barriers to international technology diffusion. Next we turn to measuring specialisat...

  18. Research of Ancient Architectures in Jin-Fen Area Based on GIS&BIM Technology

    Science.gov (United States)

    Jia, Jing; Zheng, Qiuhong; Gao, Huiying; Sun, Hai

    2017-05-01

    The number of well-preserved ancient buildings located in Shanxi Province, enjoying the absolute maximum proportion of ancient architectures in China, is about 18418, among which, 9053 buildings have the structural style of wood frame. The value of the application of BIM (Building Information Modeling) and GIS (Geographic Information System) is gradually probed and testified in the corresponding fields of ancient architecture’s spatial distribution information management, routine maintenance and special conservation & restoration, the evaluation and simulation of related disasters, such as earthquake. The research objects are ancient architectures in JIN-FEN area, which were first investigated by Sicheng LIANG and recorded in his work of “Chinese ancient architectures survey report”. The research objects, i.e. the ancient architectures in Jin-Fen area include those in Sicheng LIANG’s investigation, and further adjustments were made through authors’ on-site investigation and literature searching & collection. During this research process, the spatial distributing Geodatabase of research objects is established utilizing GIS. The BIM components library for ancient buildings is formed combining on-site investigation data and precedent classic works, such as “Yingzao Fashi”, a treatise on architectural methods in Song Dynasty, “Yongle Encyclopedia” and “Gongcheng Zuofa Zeli”, case collections of engineering practice, by the Ministry of Construction of Qing Dynasty. A building of Guangsheng temple in Hongtong county is selected as an example to elaborate the BIM model construction process based on the BIM components library for ancient buildings. Based on the foregoing work results of spatial distribution data, attribute data of features, 3D graphic information and parametric building information model, the information management system for ancient architectures in Jin-Fen Area, utilizing GIS&BIM technology, could be constructed to support the

  19. The Global Evidence Mapping Initiative: scoping research in broad topic areas.

    Science.gov (United States)

    Bragge, Peter; Clavisi, Ornella; Turner, Tari; Tavender, Emma; Collie, Alex; Gruen, Russell L

    2011-06-17

    Evidence mapping describes the quantity, design and characteristics of research in broad topic areas, in contrast to systematic reviews, which usually address narrowly-focused research questions. The breadth of evidence mapping helps to identify evidence gaps, and may guide future research efforts. The Global Evidence Mapping (GEM) Initiative was established in 2007 to create evidence maps providing an overview of existing research in Traumatic Brain Injury (TBI) and Spinal Cord Injury (SCI). The GEM evidence mapping method involved three core tasks:1. Setting the boundaries and context of the map: Definitions for the fields of TBI and SCI were clarified, the prehospital, acute inhospital and rehabilitation phases of care were delineated and relevant stakeholders (patients, carers, clinicians, researchers and policymakers) who could contribute to the mapping were identified. Researchable clinical questions were developed through consultation with key stakeholders and a broad literature search. 2. Searching for and selection of relevant studies: Evidence search and selection involved development of specific search strategies, development of inclusion and exclusion criteria, searching of relevant databases and independent screening and selection by two researchers. 3. Reporting on yield and study characteristics: Data extraction was performed at two levels - 'interventions and study design' and 'detailed study characteristics'. The evidence map and commentary reflected the depth of data extraction. One hundred and twenty-nine researchable clinical questions in TBI and SCI were identified. These questions were then prioritised into high (n = 60) and low (n = 69) importance by the stakeholders involved in question development. Since 2007, 58 263 abstracts have been screened, 3 731 full text articles have been reviewed and 1 644 relevant neurotrauma publications have been mapped, covering fifty-three high priority questions. GEM Initiative evidence maps have a broad

  20. The Global Evidence Mapping Initiative: Scoping research in broad topic areas

    Directory of Open Access Journals (Sweden)

    Tavender Emma

    2011-06-01

    Full Text Available Abstract Background Evidence mapping describes the quantity, design and characteristics of research in broad topic areas, in contrast to systematic reviews, which usually address narrowly-focused research questions. The breadth of evidence mapping helps to identify evidence gaps, and may guide future research efforts. The Global Evidence Mapping (GEM Initiative was established in 2007 to create evidence maps providing an overview of existing research in Traumatic Brain Injury (TBI and Spinal Cord Injury (SCI. Methods The GEM evidence mapping method involved three core tasks: 1. Setting the boundaries and context of the map: Definitions for the fields of TBI and SCI were clarified, the prehospital, acute inhospital and rehabilitation phases of care were delineated and relevant stakeholders (patients, carers, clinicians, researchers and policymakers who could contribute to the mapping were identified. Researchable clinical questions were developed through consultation with key stakeholders and a broad literature search. 2. Searching for and selection of relevant studies: Evidence search and selection involved development of specific search strategies, development of inclusion and exclusion criteria, searching of relevant databases and independent screening and selection by two researchers. 3. Reporting on yield and study characteristics: Data extraction was performed at two levels - 'interventions and study design' and 'detailed study characteristics'. The evidence map and commentary reflected the depth of data extraction. Results One hundred and twenty-nine researchable clinical questions in TBI and SCI were identified. These questions were then prioritised into high (n = 60 and low (n = 69 importance by the stakeholders involved in question development. Since 2007, 58 263 abstracts have been screened, 3 731 full text articles have been reviewed and 1 644 relevant neurotrauma publications have been mapped, covering fifty-three high priority

  1. Landscape of Research Areas for Zeolites and Metal-Organic Frameworks Using Computational Classification Based on Citation Networks

    Directory of Open Access Journals (Sweden)

    Takaya Ogawa

    2017-12-01

    Full Text Available The field of porous materials is widely spreading nowadays, and researchers need to read tremendous numbers of papers to obtain a “bird’s eye” view of a given research area. However, it is difficult for researchers to obtain an objective database based on statistical data without any relation to subjective knowledge related to individual research interests. Here, citation network analysis was applied for a comparative analysis of the research areas for zeolites and metal-organic frameworks as examples for porous materials. The statistical and objective data contributed to the analysis of: (1 the computational screening of research areas; (2 classification of research stages to a certain domain; (3 “well-cited” research areas; and (4 research area preferences of specific countries. Moreover, we proposed a methodology to assist researchers to gain potential research ideas by reviewing related research areas, which is based on the detection of unfocused ideas in one area but focused in the other area by a bibliometric approach.

  2. Lipid membranes on nanostructured silicon.

    Energy Technology Data Exchange (ETDEWEB)

    Slade, Andrea Lynn; Lopez, Gabriel P. (University of New Mexico, Albuquerque, NM); Ista, Linnea K. (University of New Mexico, Albuquerque, NM); O' Brien, Michael J. (University of New Mexico, Albuquerque, NM); Sasaki, Darryl Yoshio; Bisong, Paul (University of New Mexico, Albuquerque, NM); Zeineldin, Reema R. (University of New Mexico, Albuquerque, NM); Last, Julie A.; Brueck, Stephen R. J. (University of New Mexico, Albuquerque, NM)

    2004-12-01

    A unique composite nanoscale architecture that combines the self-organization and molecular dynamics of lipid membranes with a corrugated nanotextured silicon wafer was prepared and characterized with fluorescence microscopy and scanning probe microscopy. The goal of this project was to understand how such structures can be assembled for supported membrane research and how the interfacial interactions between the solid substrate and the soft, self-assembled material create unique physical and mechanical behavior through the confinement of phases in the membrane. The nanometer scale structure of the silicon wafer was produced through interference lithography followed by anisotropic wet etching. For the present study, a line pattern with 100 nm line widths, 200 nm depth and a pitch of 360 nm pitch was fabricated. Lipid membranes were successfully adsorbed on the structured silicon surface via membrane fusion techniques. The surface topology of the bilayer-Si structure was imaged using in situ tapping mode atomic force microscopy (AFM). The membrane was observed to drape over the silicon structure producing an undulated topology with amplitude of 40 nm that matched the 360 nm pitch of the silicon structure. Fluorescence recovery after photobleaching (FRAP) experiments found that on the microscale those same structures exhibit anisotropic lipid mobility that was coincident with the silicon substructure. The results showed that while the lipid membrane maintains much of its self-assembled structure in the composite architecture, the silicon substructure indeed influences the dynamics of the molecular motion within the membrane.

  3. Thin-film amorphous silicon alloy research partnership. Final technical progress report, 2 February 1995--28 February 1998

    Energy Technology Data Exchange (ETDEWEB)

    Guha, S [United Solar Systems Corp., Troy, MI (United States)

    1998-05-01

    This report describes the status and accomplishments of work performed by United Solar Systems Corp. under this subcontract. Investigations were carried out on Ag/ZnO, Ag/TiO{sub 2}/ZnO and Ag/MgF{sub 2}/ZnO back reflectors to assess their suitability for use in cell structures. Arrays of high-efficiency component cells were made over 1-ft{sup 2} areas. Single-junction top cells were made with an average stabilized power density of 5.4 mW/cm{sup 2} measured under global AM1.5 illumination. Single-junction middle cells were optimized to give average stabilized power density of 3.6 mW/cm{sup 2} under global AM1.5 illumination with a cut-on filter with {lambda} > 530 nm. Arrays of high-efficiency triple-junction cells of 0.25-cm{sup 2} active area were fabricated over 1-ft{sup 2} area with average stabilized efficiency of 12% as measured under AM1.5 illumination. A triple-junction module of a 416-cm{sup 2} aperture area was fabricated with an initial efficiency of 11.7% and stabilized efficiency of 10.24%. A 922-cm{sup 2} aperture-area module exhibited an initial efficiency of 11.5%. The novel laser-drilling approach was used successfully to fabricate modules of 1-ft{sup 2} area with shadow loss of approximately 1%. Using this laser-drilling approach, an initial total-area efficiency of 11.5% was achieved in a triple-cell structure of 12.6 cm{sup 2} area. An initial total-area efficiency of 10.6% was achieved in a module of 300-cm{sup 2} area. Reliability studies based on NREL`s Interim Qualification Testing were carried out to confirm the suitability of the module encapsulation materials and processes. 29 figs., 17 tabs.

  4. Paralympic sport: an emerging area for research and consultancy in sports biomechanics.

    Science.gov (United States)

    Keogh, Justin W L

    2011-09-01

    The Paralympic Games are the pinnacle of sport for many athletes with a disability. The overall purpose of this paper is to highlight the role that the field of sports biomechanics specifically (and sports science in general) may play in improving performance in various summer Paralympic sports through research and consultancy. To achieve this broad aim, this review provides some history and background on the Summer Paralympic Games, discusses the eligibility and classification rules, describes the potential for the constraints-led approach of dynamical systems theory to inform practice and research in this area, and reviews selected studies examining the biomechanics of the primary forms of Paralympic locomotion. Some recommendations on how sports biomechanics can help facilitate improvements in Paralympic athletic performance through applied research and consultancy are provided, along with commentary on what may be some of the most important issues addressing Paralympic sport.

  5. Critical research needs for managing coral reef marine protected areas: perspectives of academics and managers.

    Science.gov (United States)

    Cvitanovic, C; Wilson, S K; Fulton, C J; Almany, G R; Anderson, P; Babcock, R C; Ban, N C; Beeden, R J; Beger, M; Cinner, J; Dobbs, K; Evans, L S; Farnham, A; Friedman, K J; Gale, K; Gladstone, W; Grafton, Q; Graham, N A J; Gudge, S; Harrison, P L; Holmes, T H; Johnstone, N; Jones, G P; Jordan, A; Kendrick, A J; Klein, C J; Little, L R; Malcolm, H A; Morris, D; Possingham, H P; Prescott, J; Pressey, R L; Skilleter, G A; Simpson, C; Waples, K; Wilson, D; Williamson, D H

    2013-01-15

    Marine protected areas (MPAs) are a primary policy instrument for managing and protecting coral reefs. Successful MPAs ultimately depend on knowledge-based decision making, where scientific research is integrated into management actions. Fourteen coral reef MPA managers and sixteen academics from eleven research, state and federal government institutions each outlined at least five pertinent research needs for improving the management of MPAs situated in Australian coral reefs. From this list of 173 key questions, we asked members of each group to rank questions in order of urgency, redundancy and importance, which allowed us to explore the extent of perceptional mismatch and overlap among the two groups. Our results suggest the mismatch among MPA managers and academics is small, with no significant difference among the groups in terms of their respective research interests, or the type of questions they pose. However, managers prioritised spatial management and monitoring as research themes, whilst academics identified climate change, resilience, spatial management, fishing and connectivity as the most important topics. Ranking of the posed questions by the two groups was also similar, although managers were less confident about the achievability of the posed research questions and whether questions represented a knowledge gap. We conclude that improved collaboration and knowledge transfer among management and academic groups can be used to achieve similar objectives and enhance the knowledge-based management of MPAs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Fundamental research in the area of high temperature fuel cells in Russia

    Energy Technology Data Exchange (ETDEWEB)

    Dyomin, A.K.

    1996-04-01

    Research in the area of molten carbonate and solid oxide fuel cells has been conducted in Russia since the late 60`s. Institute of High Temperature Electrochemistry is the lead organisation in this area. Research in the area of materials used in fuel cells has allowed us to identify compositions of electrolytes, electrodes, current paths and transmitting, sealing and structural materials appropriate for long-term fuel cell applications. Studies of electrode processes resulted in better understanding of basic patterns of electrode reactions and in the development of a foundation for electrode structure optimization. We have developed methods to increase electrode activity levels that allowed us to reach current density levels of up to 1 amper/cm{sup 2}. Development of mathematical models of processes in high temperature fuel cells has allowed us to optimize their structure. The results of fundamental studies have been tested on laboratory mockups. MCFC mockups with up to 100 W capacity and SOFC mockups with up to 1 kW capacity have been manufactured and tested at IHTE. There are three SOFC structural options: tube, plate and modular.

  7. The 300 Area Integrated Field Research Challenge Quality Assurance Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    Fix, N. J.

    2009-04-29

    Pacific Northwest National Laboratory and a group of expert collaborators are using the U.S. Department of Energy Hanford Site 300 Area uranium plume within the footprint of the 300-FF-5 groundwater operable unit as a site for an Integrated Field-Scale Subsurface Research Challenge (IFRC). The IFRC is entitled Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on the Hanford Site 300 Area Uranium Plume Project. The theme is investigation of multi-scale mass transfer processes. A series of forefront science questions on mass transfer are posed for research that relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and measurements/approaches needed to characterize and model a mass transfer-dominated system. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the 300 Area IFRC Project. This plan is designed to be used exclusively by project staff.

  8. Research progress in volcanology in the Neapolitan area, southern Italy: a review and some alternative views

    Science.gov (United States)

    de Vivo, Benedetto; Petrosino, Paola; Lima, Annamaria; Rolandi, Giuseppe; Belkin, Harvey E.

    2010-05-01

    Comprehensive reviews are given for the major volcanic systems that occur in the greater metropolitan area of Naples, southern Italy; Mt. Somma-Vesuvius to the east and the Campi Flegrei volcanic system to the west. Also included in the review is a detailed discussion of the large, highly explosive Campania Volcanic Zone (CVZ) ignimbrite events. These volcanic areas have been studied for more than 100 years, yet significant differences of opinion exist related to fundamental issues of origin and distribution. We present some alternative views related to petrogenesis on some issues based on more than 25 years of research. The relationship between risk assessment and management that impacts the threatened society or culture and the past and ongoing fundamental volcanological research is an essential part of the science. Countries with limited resources may be forced to accept an increased risk but even highly industrialized societies may not be able to completely eliminate deaths from volcanic eruptions. Scientific studies of the hazardous regions should be comprehensive and include reasonable alternative interpretations as this information reveals the level of confidence that must be conveyed to the public officials. The authors review the state of the art of risk assessment and management of the volcanic hazards in the Neapolitan region in light of the review of research.

  9. Decision-making theories: linking the disparate research areas of individual and collective cognition.

    Science.gov (United States)

    Pelé, Marie; Sueur, Cédric

    2013-07-01

    In order to maximize their fitness, animals have to deal with different environmental and social factors that affect their everyday life. Although the way an animal behaves might enhance its fitness or survival in regard to one factor, it could compromise them regarding another. In the domain of decision sciences, research concerning decision making focuses on performances at the individual level but also at the collective one. However, between individual and collective decision making, different terms are used resulting in little or no connection between both research areas. In this paper, we reviewed how different branches of decision sciences study the same concept, mainly called speed-accuracy trade-off, and how the different results are on the same track in terms of showing the optimality of decisions. Whatever the level, individual or collective, each decision might be defined with three parameters: time or delay to decide, risk and accuracy. We strongly believe that more progress would be possible in this domain of research if these different branches were better linked, with an exchange of their results and theories. A growing amount of literature describes economics in humans and eco-ethology in birds making compromises between starvation, predation and reproduction. Numerous studies have been carried out on social cognition in primates but also birds and carnivores, and other publications describe market or reciprocal exchanges of commodities. We therefore hope that this paper will lead these different areas to a common decision science.

  10. Research on Ore-controlling factors and Metallogenic Prognosis of Dongchuan Copper Mining Area, Yunnan, China

    Science.gov (United States)

    Wang, Tianguo; Liu, Jishun; Huang, Chaowen

    2017-03-01

    Dongchuan is a famous copper producing area in China, where has good geological condition to form many copper deposits with local characteristics. This article summarizes the metallogenic regularities of Dongchuan copper deposits based on the previous works, research findings and the latest research advances. The study suggests that the Dongchuan copper-ore area has a good metallogenic background and immense prospecting potential. Copper ore is mainly found in Yinmin Formation, Luoxue Formation, Heishan Formation, Daqiaodi Formation, and in the Sinian-aged basement, and its occurrence is closely related to volcanic magmatism. The discussions regarding prospecting directions of Dongchuan copper ore were conducted based on the metallogenic regularity research, the results shows that further expanding of the exploration activities from the existing ore-bodies would be carried out; the breakthrough points focus on the Pingdingshan Formation, Qinglongshan Formation, and Daqiaodi Formation strata; at the same tine, more attention should be paid to the new types of deposits, such as Yanziya-type or hydrothermal deposits.

  11. Research progress on large-area perovskite thin films and solar modules

    Directory of Open Access Journals (Sweden)

    Zhichun Yang

    2017-12-01

    Full Text Available Organometal halide perovskites have exhibited a bright future as photovoltaic semiconductor in next generation solar cells due to their unique and promising physicochemical properties. Over the past few years, we have witnessed a tremendous progress of efficiency record evolution of perovskite solar cells (PSCs. Up to now, the highest efficiency record of PSCs has reached 22.1%; however, it was achieved at a very small device area of <0.1 cm2. With the device area increasing to mini-module scale, the efficiency record dropped dramatically. The inherent causes are mainly ascribed to inadequate quality control of large-area perovskite thin films and insufficient optimization of solar module design. In current stage of PSCs research and development, to overcome these two obstacles is in urgent need before this new technology could realize scale-up industrialization. Herein, we present an overview of recently developed strategies for preparing large-area perovskite thin films and perovskite solar modules (PSMs. At last, cost analysis and future application directions of PSMs have also been discussed.

  12. Research history and prospecting potential of gold deposits in Dongchuan Area, Yunnan, China

    Science.gov (United States)

    Huang, Chaowen; Zhang, Shugen

    2017-03-01

    The Dongchuan area in China is part of the Sichuan-Yunnan-Guizhou polymetallic metallogenic field and contains extensive ore-deposits. Although gold was first discovered in the area in the 1990s, gold exploration and research are currently limited; only five areas have currently been identified as containing gold deposits with reserves of more than 20 tons. However, the area is believed to have considerable prospecting potential. Gold deposits mainly occurring in the wall of the rock mass have been found in the upper-middle section of the Pingdingshan Group to the lower-bottom section of the Yinming Group in relation to the intrusive action and development of sodium diorite. It has been determined that the core of the anticline complex and its nearby fault zone are the major ore hosting structures and that gold-deposit prospecting should be conducted around the N-S compressive shear zone. In this study, sites are determined that have certain characteristics accompanied by a high degree of rock formation and complete assemblages of lithological composition; these are considered to be locations conducive to the prospecting of gold deposits.

  13. [Health-care research from the German Medical Association's perspective on small-area analysis].

    Science.gov (United States)

    Zorn, U

    2014-02-01

    As early as 2003, the German medical profession realized the necessity of not only forwarding medical research, but also analyzing the process of health care itself. Approved by a decision of the 108th German Medical Assembly in 2005, an initiative on health-care research paid by contributions of the medical profession was launched. Since then several projects have been supported with the results being published continuously. From the perspective of the German Medical Association, the success of the initiative also proves the effective approach of the scientific and medical communities' self-administration. Although the current results from health-care research can be used to support health-care politics and decision making at a macro level, a focus on small-area analysis tends to be an intrinsic attribute of health-care research, keeping a local approach toward changes so as to obtain real effects. Without local settings and without data reflecting the local situation, the"last mile" of a health-care system, which is the core subject of health-care research, will not be comprehensible.

  14. Significance of the Maritimes Region ecosystem research initiative to marine protected area network planning within Fisheries and Oceans Canada

    National Research Council Canada - National Science Library

    Lawton, P; Westhead, M; Greenlaw, M.E; Smith, S.J; Brown, C.J; Quigley, S; Brickman, D

    2013-01-01

    This research document outlines the relevance to Marine Protected Area (MPA) network planning of scientific work recently completed under Fisheries and Oceans Canada's Maritimes Region Ecosystem Research Initiative (ERI...

  15. Research on the Placement of the Ecological Shelter Zone in the Three Gorges Reservoir Area, China

    Science.gov (United States)

    Shan, N.; Ruan, X.

    2011-12-01

    The Three Gorges Dam is built on the middle reaches of Yangtze River (Changjiang) in south-central China, which is the world's third longest river. The Three Gorges Reservoir Region (TGRR), including the entire inundated area and 19 administrative units (counties and cities) on both sides of the river, is regarded as an environmentally sensitive area. The total area of the TGRR is approximately 58000 km2. As the Three Gorges Dam fully operated, for the flood control, the water level should be kept in the range between 145 m and 175 m and the reservoir surface water area(over 1080 km2)at a water level of 175 m, with a length of 600 km. Many of cities, villages and farms have been submerged. Moreover, as a result of reservoir operation, the water-level alternation of the reservoir is opposite to the nature, which is low water level (145m) in summer and high water level (175m) in winter. The Hydro-Fluctuation Belt, with a height of 30m, will become a new pollution source due to the riparian being flooded and the submerged areas may still contain trace amounts of toxic or radioactive materials. The environmental impacts associated with large scale reservoir area often have significant negative impacts on the environment. It affects forest cover, species in the area, some endangered, water quality, increase the likelihood of earthquakes and mudslides in the area. To solve these problems, it is necessarily to construct the Ecological Shelter Zone (ESZ) along with the edge of the reservoir area. The function of the ESZ is similar to the riparian zone in reducing flood damage, improving water quality, decreasing the levels of the nonpoint source pollution load and soil erosion and rebuilding the migration routes of plant and wildlife. However, the research of the ESZ is mainly focused on rivers at field scale by now, lack of research method on reservoir at the watershed scale. As the special nature of the Three Gorges Reservoir, the construction of the ESZ in the TGRA is

  16. Empirical research on the service mode of China’s scientific fitness demonstration area

    Directory of Open Access Journals (Sweden)

    Xu Wenqi

    2016-01-01

    Full Text Available Continuous improvement on promoting the scientific fitness service system of mass sports is an important measure to implement nationwide fitness strategy; develop sport industry; and promote sport consumption. This study takes the experimental units of scientific fitness demonstration area regulated by General Administration of Sport of China as the study objects. It combines theoretical research and empirical study together and reached the following conclusions: in order to obtain scientific, demonstrative and sustainable fitness demonstration areas, we shall stick to the guidance of our government; introduce marketing operational mechanism; combine the advantages of human capital from institutions of higher learning; and apply the PPP mode operated by the cooperation between government purchasing service and social capital, making it possible to realize the organic combination of public service and private service.

  17. Hydrology and hydrochemistry for the Rice Creek watershed of the Whiteshell Research Area, 1986--1990

    Energy Technology Data Exchange (ETDEWEB)

    Thorne, G.A.; Laporte, J.M.; Clarke, D.

    1992-12-01

    This report presents data and results of a hydrometeorological study carried out in the Rice Creek Watershed of the Whiteshell Research Area during 1986-90. Major water budget components, such as precipitation, runoff, groundwater, storage and evaporation, are evaluated and discussed. men annual precipitation was 544 mm, mean runoff was 101 mm, with evapo-transpiration as the residual being 443 mm. The steady-state groundwater component of the runoff is estimated to be less than 2 mm/unit area, or less than 2% of men annual basin yield. Water chemistry data for precipitation,l surface waters, and groundwaters are presented and the relative concentrations compared to provide information about sources of streamflow. Data on a major storm event that provided precipitation with an estimated return period of over 100 a are presented. Also discussed are the effects of beaver dams on the hydrology of a major tributary of the Rice Creek watershed. (auth)

  18. Silicon photonics for telecommunications and biomedicine

    CERN Document Server

    Fathpour, Sasan

    2011-01-01

    Given silicon's versatile material properties, use of low-cost silicon photonics continues to move beyond light-speed data transmission through fiber-optic cables and computer chips. Its application has also evolved from the device to the integrated-system level. A timely overview of this impressive growth, Silicon Photonics for Telecommunications and Biomedicine summarizes state-of-the-art developments in a wide range of areas, including optical communications, wireless technologies, and biomedical applications of silicon photonics. With contributions from world experts, this reference guides

  19. Geochemical research of soil and attic dust in Litija area, Slovenia

    Directory of Open Access Journals (Sweden)

    Mateja Jemec

    2007-12-01

    Full Text Available Geochemical research was carried as part of the environmental research project at the Geological Survey of Slovenia. The aim of the project was to determine the impact on the environment caused by heavy metals released in the environment during mining and smeltingactivity in the area of Litija. The samples of attic dust and soil (0–5 cm were examined with the view to separate the natural distribution of chemical elements in the environment from the one caused by past mining and smelting activities. Based on chemically analyses we determine two main geochemical associations and their spatial distribution. First geochemical association (Al, Co, Ce, K, La, Li, Nb, Rb, Sc, Ta, Th in Ti is influencedmainlybynatural source, the second man-made association (As, Cd, Hg, Pb, Sb, Sn in Zn is caused mainly because of mining and lead smelting.

  20. Silicon nanotube field effect transistor with core-shell gate stacks for enhanced high-performance operation and area scaling benefits

    KAUST Repository

    Fahad, Hossain M.

    2011-10-12

    We introduce the concept of a silicon nanotube field effect transistor whose unique core-shell gate stacks help achieve full volume inversion by giving a surge in minority carrier concentration in the near vicinity of the ultrathin channel and at the same time rapid roll-off at the source and drain junctions constituting velocity saturation-induced higher drive current-enhanced high performance per device with efficient real estate consumption. The core-shell gate stacks also provide superior short channel effects control than classical planar metal oxide semiconductor field effect transistor (MOSFET) and gate-all-around nanowire FET. The proposed device offers the true potential to be an ideal blend for quantum ballistic transport study of device property control by bottom-up approach and high-density integration compatibility using top-down state-of-the-art complementary metal oxide semiconductor flow. © 2011 American Chemical Society.

  1. Germanium epitaxy on silicon

    Directory of Open Access Journals (Sweden)

    Hui Ye

    2014-03-01

    Full Text Available With the rapid development of on-chip optical interconnects and optical computing in the past decade, silicon-based integrated devices for monolithic and hybrid optoelectronic integration have attracted wide attention. Due to its narrow pseudo-direct gap behavior and compatibility with Si technology, epitaxial Ge-on-Si has become a significant material for optoelectronic device applications. In this paper, we describe recent research progress on heteroepitaxy of Ge flat films and self-assembled Ge quantum dots on Si. For film growth, methods of strain modification and lattice mismatch relief are summarized, while for dot growth, key process parameters and their effects on the dot density, dot morphology and dot position are reviewed. The results indicate that epitaxial Ge-on-Si materials will play a bigger role in silicon photonics.

  2. Results of research in the area of nanotechnologies and nanomaterials. Part 2

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2014-04-01

    Full Text Available To popularize scientific achievements in construction the main results of Russian and foreign scientists’ research are published in the form of abstract. Within the investigation «Obtaining and research of physical and chemical properties of nanosized system nickel–copper» experimentally proved model of synthesis of nanosized powders of system nickel–copper based on the method of reduction of metal salts from water solution has been offered; optimal conditions for obtaining radiographic pure powders have been determined. The paper also deals with conditions for obtaining and phase composition of mixed nickel and copper hydroxides including those which are stable when stored in wet conditions. The copper hydroxide stabilization method has been proposed. The practical value of performed investigation «Research of electron structure functionalized carbon nanotubes by spectographic methods with synchronous radiation» is that it developed one of the areas of physical chemistry: complex research of electron structure of carbon nanotubes including functionalized ones was carried out by the method of experimental (spectographic with synchrotron radiation of different energies and theoretical methods; the general methods of the modern applied plasmonics aimed at identification of characteristics of defects formation in carbon nanosystems of low dimension have been developed.

  3. Competitive policies in the Nordic energy research and innovation area - eNERGIA : Synthesis report

    Energy Technology Data Exchange (ETDEWEB)

    Klitkou, Antje; Pedersen, Trond Einar; Scordato, Lisa; Mariussen, Aage

    2008-07-01

    This report outlines the energy research and innovation policy in the Nordic and Baltic countries - Denmark, Finland, Iceland, Norway, Sweden, Estonia, Latvia and Lithuania. The report is the result of the research project Competitive policies in the Nordic Energy Research and Innovation Area (eNERGIA). The project was co-funded by Nordic Energy Research and NIFU STEP. The objective of the project was to determine possible policy interventions targeted at the development and commercial promotion of promising renewable energy production technologies in the Nordic countries. The report is based on an analysis of the framework conditions for the sector innovation systems for energy production, with a focus on research and innovation policy in the Nordic and Baltic countries. We identified the key actors and institutions in all the eight countries studied. In addition, we conducted a performance assessment based on the quantitative indicators of publishing and patenting, international collaboration and funding data. Using these indicators as a basis, we conducted an analysis of the strengths, weaknesses, opportunities and threats (SWOT analysis) of the Nordic sector innovation systems for energy production. This analysis identified common or diverging characteristics, challenges, framework conditions, energy-technology specialisation and, most important of all, cases of good practice in key technologies. The project included two workshops, and the results of these are also reported here. The outcomes of the workshops have been used in several parts of the project: A Nordic workshop on the environmental consequences of deployment at scale of these technologies to replace existing energy systems, with a focus on wind energy and photovoltaic energy, carbon dioxide capture and storage, and second-generation bioenergy. A Nordic workshop on policy implications for Nordic Energy Research. The report comprises three parts: Part 1: Country reports Part 2: Technology reports

  4. Research on the structural and electronic properties of defects in amorphous silicon. Final subcontract report, September 1989--December 1990

    Energy Technology Data Exchange (ETDEWEB)

    Street, R.A. [Xerox Palo Alto Research Center, CA (United States)

    1991-12-01

    The work performed for this contract focused on the saturation of light-induced effects, hydrogen-mediated metastability and growth, defects and electronic properties, and remote hydrogen plasma growth. This work included research on hydrogen chemical reactions, hydrogen density-of-states model and metastability, hydrogen bonding configurations, a model for the role of hydrogen complexes in the metastability, and hydrogen chemical potential and growth structure. This document also covers research on thermal generation currents in p-i-n diodes, field dependence of the generation current, metastability effects at contacts, and potential fluctuations in compensated a-Si:H. Information is included on plasma diagnostics using electron spin resonance and nuclear magnetic resonance measurements of remote hydrogen plasma films.

  5. Delivering patient decision aids on the Internet: definitions, theories, current evidence, and emerging research areas.

    Science.gov (United States)

    Hoffman, Aubri S; Volk, Robert J; Saarimaki, Anton; Stirling, Christine; Li, Linda C; Härter, Martin; Kamath, Geetanjali R; Llewellyn-Thomas, Hilary

    2013-01-01

    In 2005, the International Patient Decision Aids Standards Collaboration identified twelve quality dimensions to guide assessment of patient decision aids. One dimension-the delivery of patient decision aids on the Internet-is relevant when the Internet is used to provide some or all components of a patient decision aid. Building on the original background chapter, this paper provides an updated definition for this dimension, outlines a theoretical rationale, describes current evidence, and discusses emerging research areas. An international, multidisciplinary panel of authors examined the relevant theoretical literature and empirical evidence through 2012. The updated definition distinguishes Internet-delivery of patient decision aids from online health information and clinical practice guidelines. Theories in cognitive psychology, decision psychology, communication, and education support the value of Internet features for providing interactive information and deliberative support. Dissemination and implementation theories support Internet-delivery for providing the right information (rapidly updated), to the right person (tailored), at the right time (the appropriate point in the decision making process). Additional efforts are needed to integrate the theoretical rationale and empirical evidence from health technology perspectives, such as consumer health informatics, user experience design, and human-computer interaction. As of 2012, the updated theoretical rationale and emerging evidence suggest potential benefits to delivering patient decision aids on the Internet. However, additional research is needed to identify best practices and quality metrics for Internet-based development, evaluation, and dissemination, particularly in the areas of interactivity, multimedia components, socially-generated information, and implementation strategies.

  6. Community based needs assessment in an urban area; A participatory action research project

    Directory of Open Access Journals (Sweden)

    Ahari Saeid

    2012-03-01

    Full Text Available Abstract Background Community assessment is a core function of public health. In such assessments, a commitment to community participation and empowerment is at the heart of the WHO European Healthy Cities Network, reflecting its origins in health for all and the Ottawa Charter for Health Promotion. This study employs a participation and empowerment plan in order to conduct community assessment. Methods The method of participatory action research (PAR was used. The study was carried out in an area of high socio-economic deprivation in Ardabil, a city in the northwest of Iran, which is currently served by a branch of the Social Development Center (SDC. The steering committee of the project was formed by some university faculty members, health officials and delegates form Farhikhteh non-governmental organization and representatives from twelve blocks or districts of the community. Then, the representatives were trained and then conducted focus groups in their block. The focus group findings informed the development of the questionnaire. About six hundred households were surveyed and study questionnaires were completed either during face-to-face interviews by the research team (in case of illiteracy or via self-completion. The primary question for the residents was: 'what is the most important health problem in your community? Each health problem identified by the community was weighted based on the frequency it was selected on the survey, and steering committee perception of the problem's seriousness, urgency, solvability, and financial load. Results The main problems of the area appeared to be the asphalt problem, lack of easy access to medical centers, addiction among relatives and unemployment of youth. High participation rates of community members in the steering committee and survey suggest that the PAR approach was greatly appreciated by the community and that problems identified through this research truly reflect community opinion

  7. Challenges of Family Physician Program in Urban Areas: A Qualitative Research.

    Science.gov (United States)

    Sabet Sarvestani, Raheleh; Najafi Kalyani, Majid; Alizadeh, Fariba; Askari, Alireza; Ronaghy, Hossain; Bahramali, Ehsan

    2017-07-01

    Family physicians play an essential role and act as a communicational bridge between people and the healthcare system in providing healthcare services efficiently and equitably. This study aimed at exploring the challenges of the family physician program in urban areas in Iran in 2015. This research had a descriptive exploratory design with a qualitative content analysis approach. Data were collected through semi-structured interviews between 2014 and 2015. Seventeen physicians enrolling in family physician program for at least two years were selected through purposeful sampling. Conventional content analysis was used to analyze the data. Coding and analysis of the interview data generated two categories and seven subcategories related to the challenges of the family physician program. The categories were poor infrastructure and poor incentive mechanism. Our findings captured a good picture of family physician program in urban areas to better clarify the challenges of the program and provide a foundation to plan and implement appropriate changes. Thus, our findings will give policymakers a deeper perception to confront the challenges of the family physician program in urban areas.

  8. Silicon Photonics-Silicon Raman Lasers

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 10. Silicon Photonics - Silicon Raman Lasers. P K Basu. General Article Volume 12 ... Keywords. Silicon photonics; Si Raman laser; semiconductor laser; light emitter; optical interconnect; optical communication; Indirect gap semiconductors.

  9. Low cost silicon-on-ceramic photovoltaic solar cells

    Science.gov (United States)

    Koepke, B. G.; Heaps, J. D.; Grung, B. L.; Zook, J. D.; Sibold, J. D.; Leipold, M. H.

    1980-01-01

    A technique has been developed for coating low-cost mullite-based refractory substrates with thin layers of solar cell quality silicon. The technique involves first carbonizing one surface of the ceramic and then contacting it with molten silicon. The silicon wets the carbonized surface and, under the proper thermal conditions, solidifies as a large-grained sheet. Solar cells produced from this composite silicon-on-ceramic material have exhibited total area conversion efficiencies of ten percent.

  10. Is there much variation in variation? Revisiting statistics of small area variation in health services research

    Directory of Open Access Journals (Sweden)

    Ibáñez Berta

    2009-04-01

    Full Text Available Abstract Background The importance of Small Area Variation Analysis for policy-making contrasts with the scarcity of work on the validity of the statistics used in these studies. Our study aims at 1 determining whether variation in utilization rates between health areas is higher than would be expected by chance, 2 estimating the statistical power of the variation statistics; and 3 evaluating the ability of different statistics to compare the variability among different procedures regardless of their rates. Methods Parametric bootstrap techniques were used to derive the empirical distribution for each statistic under the hypothesis of homogeneity across areas. Non-parametric procedures were used to analyze the empirical distribution for the observed statistics and compare the results in six situations (low/medium/high utilization rates and low/high variability. A small scale simulation study was conducted to assess the capacity of each statistic to discriminate between different scenarios with different degrees of variation. Results Bootstrap techniques proved to be good at quantifying the difference between the null hypothesis and the variation observed in each situation, and to construct reliable tests and confidence intervals for each of the variation statistics analyzed. Although the good performance of Systematic Component of Variation (SCV, Empirical Bayes (EB statistic shows better behaviour under the null hypothesis, it is able to detect variability if present, it is not influenced by the procedure rate and it is best able to discriminate between different degrees of heterogeneity. Conclusion The EB statistics seems to be a good alternative to more conventional statistics used in small-area variation analysis in health service research because of its robustness.

  11. [Core research areas on addiction in Spain through the Web of Science bibliographic coupling analysis (2000-2013)].

    Science.gov (United States)

    G, González-Alcaide; A, Calafat; E, Becoña

    2014-01-01

    The present study identifies the main Spanish core research areas in the area of addictions through the bibliographic coupling analysis of the publications at the Web of Science under the substance abuse heading. The bibliographic coupling methodology is the analytical procedure that determines the thematic-intellectual proximity of the documents under consideration through the identification of the shared or simultaneously cited bibliography by those documents. A factor analysis and network analysis have been carried out to cluster documents, graphically represent the existing core research areas, and analyse the interrelations between them. We have identified 30 core research areas. Alcohol is the topic of attention of 17 areas and cocaine has a strong presence in 6. Heroin and opiates are only present as prominent substances in 4 areas and cannabis and tobacco in other two for each substance. It has been found that there is a significant degree of fragmentation in the area, with the existence of numerous research foci but with few connections with each other and few documents showing shared common knowledge. Also noteworthy is the large number of emerging research areas, reflecting an incipient stage in many of the research topics. Consideration must be placed in promoting scientific consensus and cohesion of the discipline as well as to encouraging the consolidation of main lines that respond to the social problems and research challenges.

  12. Results of research in the area of nanotechnologies and nanomaterials. Part 4

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2014-08-01

    Full Text Available To popularize scientific achievements in construction the main results of Russian and foreign scientists’ research are published in the form of abstract. Within the frame of the research «Nanocomposite cabel elastrons based on polyvinylchloride and aluminum silicate» new nanocomposite materials based on polyvinylchloride elastron with organomodified montmorillonite and combinations of it with non-halogen fire flame retardant have been developed. The experiment shows that carbamide-containing organoclay is the efficient filler of polyvinylchloride elastron. The receipts and production method for new polymer nanocomposites based on PVC elastron and organomodified montmorillonite have been designed. The paper provides information on the methods to obtain nanodimensional natural fillers; principles for choosing organomodifiers and their influence on the quality of nanodimensional flaked silicate fillers; application efficiency of organoclays when modifying properties of polymer materials. All that makes the results of the research to be very useful for specialists engaged into the area of filler manufacture, creation and processing of polymer composite material and designing products of them. Specialists can use published materials in their scientific and practical activities.

  13. Research and development on a sub 100 PICO second time-of-flight system based on silicon avalanche diodes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y.; Hirsch, A.; Hauger, A.; Scharenberg, R.; Tincknell, M. [Purdue Univ., West Lafayette, IN (United States); Rai, G. [Lawrence Berkeley Lab., CA (United States)

    1991-12-31

    Particle identification requires a momentum measurement and a second independent determination either energy loss (dE/dx) or time of flight (TOF). To cover a momentum range from 0.1 GeV/c to 1.5 GeV/c in the STAR detector requires both the dE/dx and TOF techniques. This research is designed to develop the avalanche diode (AVD) detectors for TOF systems and evaluate their performance. The test of a small prototype system would be carried out at Purdue and at accelerator test beam sites. The Purdue group has developed a complete test setup for evaluating the time resolution of the AVD`s which includes fast-slow electronic channels, CAMAC based electronic modules and a temperature controlled environment. The AVDs also need to be tested in a 0.5 tesla magnetic field. The Purdue group would augment this test set up to include a magnetic field.

  14. Silicon photonics: Design, fabrication, and characterization of on-chip optical interconnects

    Science.gov (United States)

    Hsieh, I.-Wei

    devices are quite different from those of electronic devices. Minimizing propagation losses by reducing sidewall roughness to nanometer scale over a device length of several millimeters or even centimeters has prompted researchers in academia and industry to refine the fabrication process. Chapter 3 of this thesis summarizes our efforts in fabricating silicon photonic devices using standard CMOS technology. Chapter 4 describes the characterization of nonlinear effects, including self-phase modulation (SPM), cross-phase modulation (XPM), and supercontinuum generation in silicon-wire waveguides. Silicon-wire waveguides are strip waveguides with submicron transverse dimensions, which allow strong light confinement inside the silicon core. This strong optical confinement, in addition to the large third-order nonlinear optical susceptibility of crystalline silicon, leads to a net nonlinearity which is several orders of magnitude higher than the nonlinearity of silica fiber. Significant nonlinear effects can be observed and characterized over a device length of only several millimeters in silicon wires with very small input power. These effects provide opportunities for engineers to design active silicon photonic devices which are compact and energy-efficient. Chapter 5 presents a realization of an integrated SOI optical isolator, which is a critical yet often overlooked component in photonic integrated circuits. This study shows the feasibility to make a hybrid garnet/SOI active device with very promising results. Finally, Chapter 6 summarizes our demonstration of transmitting terabit-scale data streams in silicon-wire waveguides, which is an important first-step towards enabling intra-chip interconnection networks with ultra-high bandwidths. Although the scope of this thesis is limited to providing only fractional views of the whole silicon photonics area, it provides enough references for interested readers to conduct further literature research in other aspects of silicon

  15. Delivering patient decision aids on the Internet: definitions, theories, current evidence, and emerging research areas

    Science.gov (United States)

    2013-01-01

    Background In 2005, the International Patient Decision Aids Standards Collaboration identified twelve quality dimensions to guide assessment of patient decision aids. One dimension—the delivery of patient decision aids on the Internet—is relevant when the Internet is used to provide some or all components of a patient decision aid. Building on the original background chapter, this paper provides an updated definition for this dimension, outlines a theoretical rationale, describes current evidence, and discusses emerging research areas. Methods An international, multidisciplinary panel of authors examined the relevant theoretical literature and empirical evidence through 2012. Results The updated definition distinguishes Internet-delivery of patient decision aids from online health information and clinical practice guidelines. Theories in cognitive psychology, decision psychology, communication, and education support the value of Internet features for providing interactive information and deliberative support. Dissemination and implementation theories support Internet-delivery for providing the right information (rapidly updated), to the right person (tailored), at the right time (the appropriate point in the decision making process). Additional efforts are needed to integrate the theoretical rationale and empirical evidence from health technology perspectives, such as consumer health informatics, user experience design, and human-computer interaction. Despite Internet usage ranging from 74% to 85% in developed countries and 80% of users searching for health information, it is unknown how many individuals specifically seek patient decision aids on the Internet. Among the 86 randomized controlled trials in the 2011 Cochrane Collaboration’s review of patient decision aids, only four studies focused on Internet-delivery. Given the limited number of published studies, this paper particularly focused on identifying gaps in the empirical evidence base and

  16. Silicone chain extender

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a silicone chain extender, more particularly a chain extender for silicone polymers and copolymers, to a chain extended silicone polymer or copolymer and to a functionalized chain extended silicone polymer or copolymer, to a method for the preparation thereof...

  17. Tanks Focus Area Alternative Salt Processing Research and Development Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, Harry D.

    2000-11-30

    In March 2000, DOE-Headquarters (HQ) requested the Tanks Focus Area (TFA) to assume management responsibility for the Salt Processing Project technology development program at Savannah River Site. The TFA was requested to conduct several activities, including review and revision of the technology development roadmaps, development of down-selection criteria, and preparation of a comprehensive Research and Development (R&D) Program Plan for three candidate cesium removal technologies, as well as the Alpha and strontium removal processes that must also be carried out. The three cesium removal candidate technologies are Crystalline Silicotitanate (CST) Non-Elutable Ion Exchange, Caustic Side Solvent Extraction (CSSX), and Small Tank Tetraphenylborate Precipitation (STTP). This plan describes the technology development needs for each process that must be satisfied in order to reach a down-selection decision, as well as continuing technology development required to support conceptual design activities.

  18. Tanks Focus Area Alternative Salt Processing Research and Development Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, Harry D.

    2000-05-15

    In March 2000, DOE-Headquarters (HQ) requested the Tanks Focus Area (TFA)to assume management responsibility for the Salt Processing Project technology development program at Savannah River Site. The TFA was requested to conduct several activities, including review and revision of the technology development roadmaps, development of down-selection criteria, and preparation of a comprehensive Research and Development (R&D) Program Plan for three candidate cesium removal technologies, as well as the Alpha and strontium removal processes that must also be carried out. The three cesium removal candidate technologies are Crystalline Silicotitanate (CST) Non-Elutable Ion Exchange, Caustic Side Solvent Extraction (CSSX), and Small Tank Tetraphenylborate Precipitation (STTP). This plan describes the technology development needs for each process that must be satisfied in order to reach a down-selection decision, as well as continuing technology development required to support conceptual design activities.

  19. Fostering resilience among urban youth exposed to violence: a promising area for interdisciplinary research and practice.

    Science.gov (United States)

    Jain, Sonia; Cohen, Alison K

    2013-12-01

    Most studies to date have examined negative effects of exposure to community violence, in line with the deficit-based perspective. However, given that most youth exposed to community violence demonstrate positive adaptation or resilience over time, we suggest a shift in perspective, practices, and policies across systems toward identifying and building individual, family, and community assets and strengths that may more effectively support youth who have been exposed to community violence and related risks into competent, caring, and thriving adults. In this article, we review how resilience has been conceptualized and operationalized within the context of community violence, highlight gaps in literature, and offer directions for future public health research and practice. We illustrate this review with practice-based examples from public health work in the San Francisco Bay Area. Future multidisciplinary longitudinal studies that identify protective processes and successful trajectories and rigorous evaluations of strength-based policies, programs, and protective processes are needed.

  20. Large area lateral epitaxial overgrowth (LEO) of gallium nitride (GAN) thin films on silicon substrates and their characterization. Final report 1 March--30 September 99

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.F.; Linthicum, K.J.; Gehrke, T.; Thomson, D.; Ronning, C.

    1999-09-01

    Pendeo-epitaxial lateral growth (PE) of GaN epilayers on (0001) 6H-silicon carbide and (111) Si substrates has been achieved. Growth on the latter substrate was accomplished through the use of a 3C-SiC transition layer. The coalesced PE GaN epilayers were characterized using scanning electron diffraction, x-ray diffraction and photoluminescence spectroscopy. The regions of lateral growth exhibited {approximately} 0.2 deg crystallographic tilt relative to the seed layer. The GaN seed and PE epilayers grown on the 3C-SiC/Si substrates exhibited comparable optical characteristics to the GaN seed and PE grown on 6H- SiC substrates. The near band-edge emission of the GaN/3C-SiC/Si seed was 3.450 eV (FWHM approx. 19 meV) and the GaN/6H-SiC seed was 3.466 eV (FWHM approx. 4 meV).

  1. Solid State Photovoltaic Research Branch

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  2. Consanguineous Marriages among Women in Bursa Nilufer Public Health Training and Research Area

    Directory of Open Access Journals (Sweden)

    Nilufer Tavukcu

    2008-04-01

    Full Text Available AIM/BACKGROUND: The aim of this study was to evaluate socio-demographic and fertility features, opinions on consanguinity, and the types of congenital disorders encountered in the babies of women in consanguineous marriages in the Nilufer Public Health Training and Research Area in the province of Bursa in northwest Turkey. METHODS: This case-control study was conducted between September 2005 and March 2006. The case group consisted of 393 women in consanguineous marriages in the Nilufer Public Health Training and Research Area; the control group consisted of 393 women of similar age living in the same neighborhoods but in non-consanguineous marriages. RESULTS: Women involved in a consanguineous marriage were on average younger than women in the control group. The mean numbers of pregnancies, births, stillbirths, and living and deceased babies were all significantly higher among the consanguineous marriages. When the sample and the control groups were compared, it was obtained that the women in the case group were socio-economically in a lower status statistically, by means of their husband’s and their own education and occupational status, than the women in the control group. The women in the case group were more likely to believe that consanguinity is not detrimental to a child’s health, and they approved of consanguineous marriages for their own children. These opinions were held despite there being a significantly higher incidence of congenital disorders among the children of the consanguineous marriages. CONCLUSION: Women there should be offered genetic counseling to help reduce the occurrence of children being born with congenital abnormalities. [TAF Prev Med Bull. 2008; 7(2: 107-112

  3. Consanguineous Marriages among Women in Bursa Nilufer Public Health Training and Research Area

    Directory of Open Access Journals (Sweden)

    Nilufer Tavukcu

    2008-04-01

    Full Text Available AIM/BACKGROUND: The aim of this study was to evaluate socio-demographic and fertility features, opinions on consanguinity, and the types of congenital disorders encountered in the babies of women in consanguineous marriages in the Nilufer Public Health Training and Research Area in the province of Bursa in northwest Turkey. METHODS: This case-control study was conducted between September 2005 and March 2006. The case group consisted of 393 women in consanguineous marriages in the Nilufer Public Health Training and Research Area; the control group consisted of 393 women of similar age living in the same neighborhoods but in non-consanguineous marriages. RESULTS: Women involved in a consanguineous marriage were on average younger than women in the control group. The mean numbers of pregnancies, births, stillbirths, and living and deceased babies were all significantly higher among the consanguineous marriages. When the sample and the control groups were compared, it was obtained that the women in the case group were socio-economically in a lower status statistically, by means of their husband’s and their own education and occupational status, than the women in the control group. The women in the case group were more likely to believe that consanguinity is not detrimental to a child’s health, and they approved of consanguineous marriages for their own children. These opinions were held despite there being a significantly higher incidence of congenital disorders among the children of the consanguineous marriages. CONCLUSION: Women there should be offered genetic counseling to help reduce the occurrence of children being born with congenital abnormalities. [TAF Prev Med Bull 2008; 7(2.000: 107-112

  4. PROBLEMS OF TRANSCRIPTION IN THE AREA OF DIALECT RESEARCHES / AĞIZ ARASTIRMALARINDA TRANSKRIPSIYON ISARETLERININ FARKLI KULLANILMASI SORUNU

    Directory of Open Access Journals (Sweden)

    Erdinç DEMİRAY (M.A.H.

    2008-11-01

    Full Text Available Dialect researches is one of the most difficult fieldof language. In this area of dialect researches, one of themost important reason of the difficulties, encountered atthe stage of putting voice recordings into the writting andanalyzing the papers, is the differences appeared in theuse of transcription signs. Using transcription signs issuein the dialect researches should be solved and adopted acommon understanding.

  5. Climate change in the Carpathian-Balkan Area. Advancing research and cooperation

    Directory of Open Access Journals (Sweden)

    Marcel MINDRESCU

    2013-06-01

    Full Text Available The Carpathian Mountains are considered to be one of Europe’s last “wilderness” areas, but are nevertheless under heavy pressure from human activities. Examples range from large-scale activities (e.g. metal and coal mining and ecological disasters (e.g. tailing dam failures in the Toroiaga and Baia Mare areas to cross-border pollution (e.g. Chernobyl nuclear accident. The current political thrust for economic development is accelerating the pace of industrial activities, exploitation of natural resources and tourism. Romania has just recently been integrated into the European Union and many community-based projects were initiated to evaluate problems related to climatic and anthropogenic impacts.The diversity of landforms that characterize the Carpathian region encompassing mountain ranges and large spans of adjacent lowlands and the dynamic interplay between North Atlantic, continental, and Mediterranean atmospheric circulation patterns in southeastern Europe, have resulted in extremely fragmented habitats and exceptional biodiversity (Veres and Mindrescu, 2013. However, the Carpathian Mountains remain the least studied mountain environment in Europe, as reflected for example by the low number of well-dated and high-resolution paleorecords (e.g. Buczkó et al. 2009. Rose et al. (2009 published a pollution history study from a lake in the Retezat Mountains at the western extremity of the Southern Carpathians, but no paleoenvironmental studies exist for the rest of the mountain range, despite the abundance of suitable sites (Akinyemi et al., 2013.An interdisciplinary approach to geoscience is particularly important in this vast research field (geosciences, as innovative science is increasingly stimulated by studies that cross disciplinary boundaries and thus benefit from multiple research methods and viewpoints. Grasping this concept has led us to encourage interdisciplinary cooperation by creating “meeting places” where geoscience

  6. Statistical experiments using the multiple regression research for prediction of proper hardness in areas of phosphorus cast–iron brake shoes manufacturing

    Science.gov (United States)

    Kiss, I.; Cioată, V. G.; Ratiu, S. A.; Rackov, M.; Penčić, M.

    2018-01-01

    Multivariate research is important in areas of cast–iron brake shoes manufacturing, because many variables interact with each other simultaneously. This article focuses on expressing the multiple linear regression model related to the hardness assurance by the chemical composition of the phosphorous cast irons destined to the brake shoes, having in view that the regression coefficients will illustrate the unrelated contributions of each independent variable towards predicting the dependent variable. In order to settle the multiple correlations between the hardness of the cast–iron brake shoes, and their chemical compositions several regression equations has been proposed. Is searched a mathematical solution which can determine the optimum chemical composition for the hardness desirable values. Starting from the above–mentioned affirmations two new statistical experiments are effectuated related to the values of Phosphorus [P], Manganese [Mn] and Silicon [Si]. Therefore, the regression equations, which describe the mathematical dependency between the above–mentioned elements and the hardness, are determined. As result, several correlation charts will be revealed.

  7. A Printable Silicon Nano-Field Effect Transistor with High Operating Frequency for Large-Area Deployable Active Phased-Array Antennas Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Flexible electronic circuits can be easily integrated with large area (>10m aperture), inflatable antennas to provide distributed control and processing...

  8. CAPriCORN: Chicago Area Patient-Centered Outcomes Research Network

    Science.gov (United States)

    Kho, Abel N; Hynes, Denise M; Goel, Satyender; Solomonides, Anthony E; Price, Ron; Hota, Bala; Sims, Shannon A; Bahroos, Neil; Angulo, Francisco; Trick, William E; Tarlov, Elizabeth; Rachman, Fred D; Hamilton, Andrew; Kaleba, Erin O; Badlani, Sameer; Volchenboum, Samuel L; Silverstein, Jonathan C; Tobin, Jonathan N; Schwartz, Michael A; Levine, David; Wong, John B; Kennedy, Richard H; Krishnan, Jerry A; Meltzer, David O; Collins, John M; Mazany, Terry

    2014-01-01

    The Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN) represents an unprecedented collaboration across diverse healthcare institutions including private, county, and state hospitals and health systems, a consortium of Federally Qualified Health Centers, and two Department of Veterans Affairs hospitals. CAPriCORN builds on the strengths of our institutions to develop a cross-cutting infrastructure for sustainable and patient-centered comparative effectiveness research in Chicago. Unique aspects include collaboration with the University HealthSystem Consortium to aggregate data across sites, a centralized communication center to integrate patient recruitment with the data infrastructure, and a centralized institutional review board to ensure a strong and efficient human subject protection program. With coordination by the Chicago Community Trust and the Illinois Medical District Commission, CAPriCORN will model how healthcare institutions can overcome barriers of data integration, marketplace competition, and care fragmentation to develop, test, and implement strategies to improve care for diverse populations and reduce health disparities. PMID:24821736

  9. Assessment of Forest Management in Protected Areas Based on Multidisciplinary Research

    Directory of Open Access Journals (Sweden)

    Ivo Machar

    2016-11-01

    Full Text Available The remnants of primeval Norway spruce forests in the European temperate zone are crucial for maintaining forest biodiversity in high mountain landscapes. This paper presents results of a multidisciplinary research and evaluation project on the management practices for mountain spruce forests in the Natura 2000 site (National Nature Reserve Serak-Keprnik in the Hruby Jesenik Mountains, the Czech Republic. Results are based on combining research on the historical development of the forest ecosystem and predictions of future dynamics using a forest growth simulation model. The presented results show that a non-intervention management strategy for mountain spruce forest in the next 50 years complies with the Natura 2000 requirement to maintain the existing character of the forest habitat. Thus, the results indicate that the current management plan for the spruce forests does not require significant corrections in the context of its conservation goals (i.e., maintaining biodiversity and current character of the forest ecosystem dominated by Norway spruce. The results of this study suggest that combining the knowledge of historical development with forest inventory data using forest growth simulation represents a suitable support tool for the assessment of management practices for forest habitats in protected areas.

  10. Turning soil survey data into digital soil maps in the Energy Region Eger Research Model Area

    Science.gov (United States)

    Pásztor, László; Dobos, Anna; Kürti, Lívia; Takács, Katalin; Laborczi, Annamária

    2015-04-01

    Agria-Innoregion Knowledge Centre of the Eszterházy Károly College has carried out targeted basic researches in the field of renewable energy sources and climate change in the framework of TÁMOP-4.2.2.A-11/1/KONV project. The project has covered certain issues, which require the specific knowledge of the soil cover; for example: (i) investigation of quantitative and qualitative characteristics of natural and landscape resources; (ii) determination of local amount and characteristics of renewable energy sources; (iii) natural/environmental risk analysis by surveying the risk factors. The Energy Region Eger Research Model Area consists of 23 villages and is located in North-Hungary, at the Western part of Bükkalja. Bükkalja is a pediment surface with erosional valleys and dense river network. The diverse morphology of this area results diversity in soil types and soil properties as well. There was large-scale (1:10,000 and 1:25,000 scale) soil mappings in this area in the 1960's and 1970's which provided soil maps, but with reduced spatial coverage and not with fully functional thematics. To achive the recent tasks (like planning suitable/optimal land-use system, estimating biomass production and development of agricultural and ecomonic systems in terms of sustainable regional development) new survey was planned and carried out by the staff of the College. To map the soils in the study area 10 to 22 soil profiles were uncovered per settlement in 2013 and 2014. Field work was carried out according to the FAO Guidelines for Soil Description and WRB soil classification system was used for naming soils. According to the general goal of soil mapping the survey data had to be spatially extended to regionalize the collected thematic local knowledge related to soil cover. Firstly three thematic maps were compiled by digital soil mapping methods: thickness of topsoil, genetic soil type and rate of surface erosion. High resolution digital elevation model, Earth

  11. Nanocrystalline silicon in biological studies

    Energy Technology Data Exchange (ETDEWEB)

    Fucikova, Anna [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16, Prague 2 (Czech Republic); Institute of Physics AS CR, v. v. i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Valenta, Jan [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16, Prague 2 (Czech Republic); Pelant, Ivan; Kusova, Katerina [Institute of Physics AS CR, v. v. i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Brezina, Vitezslav [Institute of Systems Biology and Ecology AS CR, v. v. i., Zamek 136, 373 33 Nove Hrady (Czech Republic)

    2011-03-15

    Porous silicon and similar materials, like micro- and nanocrystalline silicon, are nowadays studied not only in physical research (e.g. optical gain studies, electro-optical devices, solar energy conversion), but they are very promising also in biological research as fluorescent labels, biological sensors, drug delivery systems or scaffold for various tissues. We are giving an overview of various approaches of preparation of micro- and nanocrystalline silicon and current studies of applications with main focus on biology and medicine. In contrast to other nanomaterials used in biological studies (e.g. carbon nanotubes, fullerenes, cadmium containing quantum dots) silicon based nanomaterials show very good biocompatibility and low cytotoxicity. Therefore, these materials have potential to become powerful tools for in vivo investigation of life processes on subcellular and molecular level. Our group concentrates on developing of gentle fluorescent label based on porous silicon for single molecule detection in the cell. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Optimizing the use of breed types in developing country livestock production systems: a neglected research area.

    Science.gov (United States)

    Marshall, K

    2014-10-01

    Developing country livestock production systems are diverse and dynamic, and include those where existing indigenous breeds are currently optimal and likely to remain so, those where non-indigenous breed types are already in common use, and systems that are changing, such as by intensification, where the introduction of new breed types represents significant opportunities. These include opportunities to improve the livelihood of the world's poor, increase food and nutrition security and enhance environmental sustainability. At present, very little research has focused on this issue, such that significant knowledge gaps in relation to breed-change interventions remain. The purpose of this study is to raise awareness of this issue and suggests strategic research areas to begin filling these knowledge gaps. Such strategic research would include (i) assessing the impact of differing breed types in developing country livestock productions systems, from a range of viewpoints including intrahousehold livelihood benefit, food and nutrition security at different scales, and environmental sustainability; (ii) identification of specific livestock production systems within developing countries, and the type of livestock keepers within these system, that are most likely to benefit from new breed types; and (iii) identification of new breed types as candidates for in-situ testing within these systems, such as through the use of spatial analysis to identify similar production environments combined with community acceptance studies. Results of these studies would primarily assist stakeholders in agriculture, including both policy makers and livestock keepers, to make informed decisions on the potential use of new breed types. © 2014 Blackwell Verlag GmbH.

  13. The availabilities of arsenic and cadmium in rice paddy fields from a mining area: The role of soil extractable and plant silicon.

    Science.gov (United States)

    Yu, Huan-Yun; Ding, Xiaodong; Li, Fangbai; Wang, Xiangqin; Zhang, Shirong; Yi, Jicai; Liu, Chuanping; Xu, Xianghua; Wang, Qi

    2016-08-01

    Adequate silicon (Si) can greatly boost rice yield and improve grain quality through alleviating stresses associated with heavy metals and metalloids such as arsenic (As) and cadmium (Cd). The soil plant-available Si is relatively low in South China due to severe desilicification and allitization of the soils in this region. Conversely, pollution of heavy metals and metalloids in the soils of this region occurs widely, especially As and Cd pollution in paddy soil. Therefore, evaluating the plant availability of Si in paddy soil of South China and examining its correlation with the availability of heavy metals and metalloids are of great significance. Accordingly, in our study, 107 pairs of soil and rice plant samples were collected from paddy fields contaminated by As and Cd in South China. Significantly positive correlations between Si in rice plants and Si fractions in soils extracted with citric acid, NaOAc-HOAc buffer, and oxalate-ammonium oxalate buffer suggest that these extractants are more suitable for use in extracting plant-available Si in the soils of our present study. Significantly negative correlations between different Si fractions and As or Cd in rice plant tissues and negative exponential correlations between the molar ratios of Si to As/Cd in rice roots, straws, husks or grains and As/Cd in rice grains indicate that Si can significantly alleviate the accumulation of As/Cd from soils to the rice plants. Finally, a contribution assessment of soil properties to As/Cd accumulation in rice grains based on random forest showed that in addition to Si concentrations in soil or rice plants, other factors such as Fe fractions and total phosphorus also contributed largely to As/Cd accumulation in rice grains. Overall, Si exhibited its unique role in mitigating As or Cd stress in rice, and our study results provide strong field evidence for this role. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. [Research progress on remote sensing of ecological and environmental changes in the Three Gorges Reservoir area, China].

    Science.gov (United States)

    Teng, Ming-jun; Zeng, Li-xiong; Xiao, Wen-fa; Zhou, Zhi-xiang; Huang, Zhi-lin; Wang, Peng-cheng; Dian, Yuan-yong

    2014-12-01

    The Three Gorges Reservoir area (TGR area) , one of the most sensitive ecological zones in China, has dramatically changes in ecosystem configurations and services driven by the Three Gorges Engineering Project and its related human activities. Thus, understanding the dynamics of ecosystem configurations, ecological processes and ecosystem services is an attractive and critical issue to promote regional ecological security of the TGR area. The remote sensing of environment is a promising approach to the target and is thus increasingly applied to and ecosystem dynamics of the TGR area on mid- and macro-scales. However, current researches often showed controversial results in ecological and environmental changes in the TGR area due to the differences in remote sensing data, scale, and land-use/cover classification. Due to the complexity of ecological configurations and human activities, challenges still exist in the remote-sensing based research of ecological and environmental changes in the TGR area. The purpose of this review was to summarize the research advances in remote sensing of ecological and environmental changes in the TGR area. The status, challenges and trends of ecological and environmental remote-sensing in the TGR area were further discussed and concluded in the aspect of land-use/land-cover, vegetation dynamics, soil and water security, ecosystem services, ecosystem health and its management. The further researches on the remote sensing of ecological and environmental changes were proposed to improve the ecosystem management of the TGR area.

  15. SILICON REFINING BY VACUUM TREATMENT

    Directory of Open Access Journals (Sweden)

    André Alexandrino Lotto

    2014-12-01

    Full Text Available This work aims to investigate the phosphorus removal by vacuum from metallurgical grade silicon (MGSi (98.5% to 99% Si. Melting experiments were carried out in a vacuum induction furnace, varying parameters such as temperature, time and relation area exposed to the vacuum / volume of molten silicon. The results of chemical analysis were obtained by inductively coupled plasma (ICP, and evaluated based on thermodynamic and kinetic aspects of the reaction of vaporization of the phosphorus in the silicon. The phosphorus was decreased from 33 to approximately 1.5 ppm after three hours of vacuum treatment, concluding that the evaporation step is the controlling step of the process for parameters of temperature, pressure and agitation used and refining by this process is technically feasible.

  16. Long-term geomorphological evolution in the Abruzzo area, Central Italy: twenty years of research

    Directory of Open Access Journals (Sweden)

    Miccadei Enrico

    2017-02-01

    Full Text Available The most recent research studies into the long-term landscape evolution of the Abruzzo area, carried out over the last twenty years at the “G. d’Annunzio” University of Chieti-Pescara, are based on an integrated approach incorporating structural geology and geomorphology and, in particular, the geomorphometry of topographic and hydrographic aspects, geological and structural-geomorphological surveys and mapping supported by morpho-stratigraphic and chronological constraints. The geomorphological analyses have allowed us to outline the main stages of geomorphological evolution and to identify the factors that have contributed to the landscape shaping of the Apennine Chain, the Adriatic Piedmont and the fluvial plains and coastal sectors, up to the Tremiti islands. In the Apennine Chain, landscape evolution — in a ridge, valley and basin system — is connected to the regional uplift, local tectonic subsidence and local base level variations, which have led to changes in the drainage systems, from exoreic to endorheic (in the intermontane basins and then to exoreic again. In the Adriatic Piedmont, landscape shaping is connected to uplifting and eustatic sea-level fluctuations, which have induced the formation of a structure-controlled drainage system and the shaping of systems of entrenched alluvial fans and large consequent river valleys, with flights of river terraces. In the coastal Adriatic area — composed of a coastal plain-coastal slope system (northern and southern coast and of a cliffed rocky coast (central coast, Tremiti interrupted by river valleys — landscape shaping is the result of selective erosion due to the interaction between marine geomorphic processes and slope processes connected to Late Quaternary eustatic fluctuations.

  17. ORGANIZATIONAL AND LEGAL RESEARCH OF INDICATORS OF INCIDENCE AND PREVALENCE OF DIABETES MELLITUS IN COUNTRYSIDE AREAS

    Directory of Open Access Journals (Sweden)

    Zbrozhek SI

    2017-03-01

    Full Text Available Introduction. For recent decades in Ukraine populations’ health indicators became quite serious negative trends: increased mortality rates among people of working age, morbidity, reduced life expectancy and more. It should also be noted that one of the main indicators of the state, its civilization and competitiveness is the degree of orientation of the state to improve the health of citizens, legal and organizational improvement of the healthcare sector. The financial and economic crisis has significantly exacerbated the problems associated with the provision of medical care in Ukraine, ensuring its availability and good quality. The current healthcare system is fair and complaints from the public, and the medical staff, it is still not able to adequately meet the needs of the population in healthcare, to ensure the availability, quality and timeliness of health services, adequate prevention of morbidity, mortality and more. The need for healthcare reform emphasizes the failure to ensure the proper conditions existing in state funding and to implement effective schemes for full competition in the healthcare and pharmaceutical provision in countryside areas is therefore, in Ukraine implemented new organizational and legal approaches in reforming the health service. That is why in Ukraine implementing processes that are transparent, will reduce unnecessary costs for public administration and improve accessibility of the medications in countryside areas of different clinical and pharmacological, classification, nomenclature, legal and regulatory groups used in the pharmacotherapy of diabetes mellitus. Materials and methods. The organizational and legal, forensic and pharmaceutical researches were conducted in countryside areas at the regional level on example of the Kharkiv region on the basis of 62 public healthcare institutions, 16 public enterprises of healthcare and health companies of other ownership. Materials of the research were: the

  18. Let’s talk silicon

    Science.gov (United States)

    While silicon (Si) has been a known plant nutrient for centuries, how plants use this element is still poorly understood. Researchers have identified how plants acquire Si from the environment and transport the element to all plant tissues, including roots, stems, petioles, leaves and flowers. We ...

  19. Silicon Micromachined Microlens Array for THz Antennas

    Science.gov (United States)

    Lee, Choonsup; Chattopadhyay, Goutam; Mehdi, IImran; Gill, John J.; Jung-Kubiak, Cecile D.; Llombart, Nuria

    2013-01-01

    5 5 silicon microlens array was developed using a silicon micromachining technique for a silicon-based THz antenna array. The feature of the silicon micromachining technique enables one to microfabricate an unlimited number of microlens arrays at one time with good uniformity on a silicon wafer. This technique will resolve one of the key issues in building a THz camera, which is to integrate antennas in a detector array. The conventional approach of building single-pixel receivers and stacking them to form a multi-pixel receiver is not suited at THz because a single-pixel receiver already has difficulty fitting into mass, volume, and power budgets, especially in space applications. In this proposed technique, one has controllability on both diameter and curvature of a silicon microlens. First of all, the diameter of microlens depends on how thick photoresist one could coat and pattern. So far, the diameter of a 6- mm photoresist microlens with 400 m in height has been successfully microfabricated. Based on current researchers experiences, a diameter larger than 1-cm photoresist microlens array would be feasible. In order to control the curvature of the microlens, the following process variables could be used: 1. Amount of photoresist: It determines the curvature of the photoresist microlens. Since the photoresist lens is transferred onto the silicon substrate, it will directly control the curvature of the silicon microlens. 2. Etching selectivity between photoresist and silicon: The photoresist microlens is formed by thermal reflow. In order to transfer the exact photoresist curvature onto silicon, there needs to be etching selectivity of 1:1 between silicon and photoresist. However, by varying the etching selectivity, one could control the curvature of the silicon microlens. The figure shows the microfabricated silicon microlens 5 x5 array. The diameter of the microlens located in the center is about 2.5 mm. The measured 3-D profile of the microlens surface has a

  20. Nanotechnology for social needs: contributions from Latin American research in the areas of health, energy and water

    Science.gov (United States)

    Invernizzi, Noela; Foladori, Guillermo; Robles-Belmont, Eduardo; Záyago Lau, Edgar; Figueroa, Edgar Arteaga; Bagattolli, Carolina; Carrozza, Tomás Javier; Chiancone, Adriana; Urquijo, William

    2015-05-01

    This paper reviews, based on data from scientific publications and research groups, the state of the art of nanotechnology research applied to the areas of medicine, energy and water in Latin America. Such areas have been considered as particularly relevant in order to meet the social needs of the developing countries. It is shown that the countries in the region have incorporated these areas to their nanotechnology agendas and several countries have increasing research capacities. However, such capacities are concentrated in Brazil and Mexico, while the regional cooperation networks are still weak. Although the research topics tend to align with relevant social issues, there are still a number of challenges so as the results of such investigations may be effectively reflected in quality of life improvements; one of them is that many publications and research topics are on basic science, which makes it difficult to evaluate their potential application field.

  1. Nanotechnology for social needs: contributions from Latin American research in the areas of health, energy and water

    Energy Technology Data Exchange (ETDEWEB)

    Invernizzi, Noela, E-mail: noela@ufpr.br; Foladori, Guillermo; Robles-Belmont, Eduardo; Záyago Lau, Edgar; Figueroa, Edgar Arteaga; Bagattolli, Carolina; Carrozza, Tomás Javier; Chiancone, Adriana; Urquijo, William [Universidade Federal do Paraná, Programa de Pós-Graduação em Políticas Públicas (Brazil)

    2015-05-15

    This paper reviews, based on data from scientific publications and research groups, the state of the art of nanotechnology research applied to the areas of medicine, energy and water in Latin America. Such areas have been considered as particularly relevant in order to meet the social needs of the developing countries. It is shown that the countries in the region have incorporated these areas to their nanotechnology agendas and several countries have increasing research capacities. However, such capacities are concentrated in Brazil and Mexico, while the regional cooperation networks are still weak. Although the research topics tend to align with relevant social issues, there are still a number of challenges so as the results of such investigations may be effectively reflected in quality of life improvements; one of them is that many publications and research topics are on basic science, which makes it difficult to evaluate their potential application field.

  2. A brief review of recent developments in the designs that prevent bio-fouling on silicon and silicon-based materials

    OpenAIRE

    Zhang, Xiaoning; Brodus, DaShan; Hollimon, Valerie; Hu, Hongmei

    2017-01-01

    Silicon and silicon-based materials are essential to our daily life. They are widely used in healthcare and manufacturing. However, silicon and silicon-based materials are susceptible to bio-fouling, which is of great concern in numerous applications. To date, interdisciplinary research in surface science, polymer science, biology, and engineering has led to the implementation of antifouling strategies for silicon-based materials. However, a review to discuss those antifouling strategies for ...

  3. Uncertainty in the Sphere of the Industry 4.0 – Potential Areas to Research

    Directory of Open Access Journals (Sweden)

    Andrzej Magruk

    2016-12-01

    Full Text Available The world stands on the threshold of a new age of technology, which will launch a fourth industrial revolution (Industry 4.0. According to this idea, web-based network will support smart factories at every stage of the work on the product, from design through to servicing and recycling. It is a vision of a world in which the real environment connects to the digital one using follows driving forces: Internet of things, cloud computing, big data, cyber-physical systems, and others. The Industry 4.0 concept is based on developing smart chains preparation based on communicating with each other means of production, products, components, plants, humans. Established in Germany, the concept of Industry 4.0, is the brainchild – its beginning reaches 2011. It is therefore fraught with high level of uncertainty in many aspects (economic, social, technological, legal, etc.. The main aim of this article is to analyze different dimensions of uncertainty regarding the Industry 4.0, both in terms of opportunities and threats. Due to the freshness of the topic and the great complexity of the Industry 4.0 phenomenon, the main aim of the article is to identify potential areas requiring the necessary research in order minimizing negative – today uncertain – effects occurring in both the design concept Industry 4.0 as well as during its functioning.

  4. Attention and the control of posture and gait: a review of an emerging area of research.

    Science.gov (United States)

    Woollacott, Marjorie; Shumway-Cook, Anne

    2002-08-01

    Research on the relationship between attention and the control of posture and gait is a new and expanding area with studies on young adults revealing the role of cognitive factors in the control of balance during standing and walking. The use of dual task paradigms to examine the effect of age related changes in attentional requirements of balance control and age-related reductions in stability when performing a secondary task has shown that these are important contributors to instability in both healthy and balance-impaired older adults. The attentional demands of balance control vary depending on the complexity of the task and the type of secondary task being performed. New clinical assessment methods incorporating dual-task paradigms are helpful in revealing the effect of disease (e.g. Parkinson's disease) on the ability to allocate attention to postural tasks and appear to be sensitive measures in both predicting fall risk and in documenting recovery of stability. Copyright 2002 Elsevier Science B.V.

  5. Researches of Optimum Leaf Area Index Dynamicmodels for Rape(brassica Napus L.)

    Science.gov (United States)

    Cao, Hongxin; Zhang, Chunlei; Li, Guangming; Zhang, Baojun; Zhao, Suolao; Wang, Baoqing; Jin, Zhiqing; Zhu, Dawei; Zhu, Juanjuan; Wei, Xiufang

    The objectives of developing optimum leaf area index dynamic models for rape (OLAIDM) was to develop Rape Cultivation Simulation-Optimization- Decision Making System(Rape-CSODS) , to design its planting , to regulate and control its growth and development, and to fulfill its high yield, good quality, high benefits and standard production eventually. The OLAIDM were developed based on field experiments with 3 cultivars, 6 sowing dates, 2 types of plant pattern and 4 sites from 2002 to 2007 in middle and lower valley of Yangtze river in China and relative data from references of rape researches, employed ideas of R/WCSODS (Rice/Wheat Cultivation Simulation- Optimization-Decision Making System), and in the same time, the OLAIMR and its parameters also were assessed, calibrated and tested. The average absolute deviation(de), correlation coefficients(r) and the standard errors of their absolute deviation(Sde) of between the observed and simulated values for LAI of two cultivars in Wuhan and Nanjing were -0.03~0.1533, 0.9707~0.9997 and0.1332~0.4032, respectively. 1:1 line of them were in Fig. 1 to 4. Multi-factors such as the ramification types, cultivars, and light et al. were taken into account in this study, therefore, the OLAIDM with general adaptability, clear yield aim, mechanism, and dynamic characteristic can simulate optimum LAI dynamic for rape under different sites, cultivars and ramification types, and yielding levels.

  6. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks; (1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  7. High-efficiency crystalline silicon technology development

    Science.gov (United States)

    Prince, M. B.

    1984-01-01

    The rationale for pursuing high efficiency crystalline silicon technology research is discussed. Photovoltaic energy systems are reviewed as to their cost effectiveness and their competitiveness with other energy systems. The parameters of energy system life are listed and briefly reviewed.

  8. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks;(1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  9. Participation of oxygen and carbon in formation of oxidation-induced stacking faults in monocrystalline silicon

    Directory of Open Access Journals (Sweden)

    Иван Федорович Червоный

    2015-11-01

    Full Text Available It is experimentally established, that density of oxidation-induced stacking faults (OISF in the boron doped monocrystalline silicon plates, that above, than it is more relation of oxygen atoms concentration to carbon atoms concentration in them.On research results of geometry of OISF rings in the different sections of single-crystal geometry of areas is reconstructed with their different closeness. At adjustment of the growing modes of single-crystals of silicon the increase of output of suitable product is observed

  10. Silicon quantum dots for biological applications.

    Science.gov (United States)

    Chinnathambi, Shanmugavel; Chen, Song; Ganesan, Singaravelu; Hanagata, Nobutaka

    2014-01-01

    Semiconductor nanoparticles (or quantum dots, QDs) exhibit unique optical and electronic properties such as size-controlled fluorescence, high quantum yields, and stability against photobleaching. These properties allow QDs to be used as optical labels for multiplexed imaging and in drug delivery detection systems. Luminescent silicon QDs and surface-modified silicon QDs have also been developed as potential minimally toxic fluorescent probes for bioapplications. Silicon, a well-known power electronic semiconductor material, is considered an extremely biocompatible material, in particular with respect to blood. This review article summarizes existing knowledge related to and recent research progress made in the methods for synthesizing silicon QDs, as well as their optical properties and surface-modification processes. In addition, drug delivery systems and in vitro and in vivo imaging applications that use silicon QDs are also discussed. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Silicon takes a spin

    NARCIS (Netherlands)

    Jansen, R.

    An efficient way to transport electron spins from a ferromagnet into silicon essentially makes silicon magnetic, and provides an exciting step towards integration of magnetism and mainstream semiconductor electronics.

  12. Implementation of research results to prevent land degradation in viticultural areas

    Science.gov (United States)

    Marqués Pérez, Maria Jose; Bienes, Ramon; de Benito, Alejandro; Velasco, Ana

    2013-04-01

    This study shows the lack of interest of land users to establish contact with scientific institutions and their reluctance to change their traditional way to manage their soils. It is conducted in Madrid and Castilla La Mancha, Spain, where the production of wine is an important source of income. The basic research was dealing with sustainable land management in sloping vineyards to prevent soil degradation. The usual reduced tillage practice in the area is compared with different cover grasses in the inter-rows of vines. The results demonstrate that these managements are able to increase soil organic matter, improve infiltration, reduce runoff and soil loss and increase soil aggregate stability. Nevertheless a decrease in production is noticed in some permanent cover treatments. A survey to know the feasibility of implementation of this sustainable land management was conducted. Less than 5% of vine growers coming to cellars and cooperatives were willing to be interviewed. Finally 64 vine growers answered a questionnaire regarding different aspects of their environmental concerns, age, land management practices and economic situation. The majority of respondents (82%) are worried about erosion problems in their sloping vineyards. They were informed about the results of the abovementioned project but only 32% of them would change the cultivation by grasses in the inter-rows. The respondents were not old (72% below 50 years old), and the agriculture was not their first activity (69% had other different sources of income). It is remarkable that they have some misunderstandings and lack of knowledge in questions regarding soil conservation. Only 3% of them receive some kind of economic aid from the institutions to avoid land degradation. This could be related to the small or medium size of their lands as 87% of them have plots smaller than 50 ha. The extension services and policy makers have to face this situation to achieve the proper implementation of scientific

  13. Rabbit Production in Selected Urban Areas of Southern Ghana: Status and Implications for Policy and Research

    Directory of Open Access Journals (Sweden)

    DY Osei

    2012-05-01

    Full Text Available A survey was conducted to elicit information on rabbit keeping in 26 urban areas of southern Ghana. The average age of the rabbit keepers was 44.3 years, and 95.5% of the keepers had formal education. Most of the producers got into rabbit keeping for money to meet urgent family needs, while household consumption was a major factor influencing the decision for rearing rabbits. Personal savings was the main source of income for the establishment of the rabbit enterprises. The major breeds of rabbits kept were the California White, New Zealand White and crossbreds of varied genetic variations. Backyard, small-scale and medium-scale commercial rabbit holdings were held by 18.2, 51.7 and 30.2% of the keepers respectively. The average rabbit population per farm was 77.8, with an average of 8.4 bucks, 21.6 does. Young rabbits formed 70.0% of the rabbit population. Owners of rabbitries usually cared for their animals as hired labour was expensive and often not available. High cost of feed was the most significant constraint to rabbit keeping, and mange was the most common disease affecting the rabbits. Marketing of rabbits was not organized, and this served as a disincentive to expanding the holdings. The rabbits were mostly sold either life or as fresh carcasses at the farm gate. To ensure a rapid growth of the rabbit industry, research should be undertaken to address the identified constraints to production while appropriate policies are put in place to enhance the growth of the industry. Keywords: rabbit keeping, socio-economic characteristics, farming technologies   Animal Production 14(2:131-139

  14. Producing Silicon Carbide/Silicon Nitride Fibers

    Science.gov (United States)

    1986-01-01

    Manufacturing process makes CxSiyNz fibers. Precursor fibers spun from extruding machine charged with polycarbosilazane resin. When pyrolyzed, resin converted to cross-linked mixture of silicon carbide and silicon nitride, still in fiber form. CxSiyNz fibers promising substitutes for carbon fibers in high-strength, low-weight composites where high electrical conductivity unwanted.

  15. Timber resource statistics for the north interior resource area of California. Forest Service research bulletin

    Energy Technology Data Exchange (ETDEWEB)

    Waddell, K.L.; Bassett, P.M.

    1997-03-01

    This report is a summary of timber resource statistics for the North Interior Resource Area of California, which includes Lassen, Modoc, Shasta, Siskiyou, and Trinity Counties. Data were collected as part of a statewide multiresource inventory. The inventory sampled private and public lands except reserved areas and National Forests. The National Forest System provided data from regional inventories of the Lassen, Mendocino, Modoc, Six Rivers, Plumas, Shasta-Trinity, Rogue River, and Toiyabe National Forests. Area information for parks and other reserves was obtained directly from the organizations managing these areas. Statistical tables summarize all ownerships and provide estimates of land area, timber volume, growth, mortality , and harvest. Estimates of periodic change of timberland area and timber volume are presented for all ownerships outside National Forests.

  16. Silicon: electrochemistry and luminescence

    NARCIS (Netherlands)

    Kooij, Ernst Stefan

    1997-01-01

    The electrochemistry of crystalline and porous silicon and the luminescence from porous silicon has been studied. One chapter deals with a model for the anodic dissolution of silicon in HF solution. In following chapters both the electrochemistry and various ways of generating visible

  17. Towards neuromorphic electronics: Memristors on foldable silicon fabric

    KAUST Repository

    Ghoneim, Mohamed T.

    2014-11-01

    The advantages associated with neuromorphic computation are rich areas of complex research. We address the fabrication challenge of building neuromorphic devices on structurally foldable platform with high integration density. We present a CMOS compatible fabrication process to demonstrate for the first time memristive devices fabricated on bulk monocrystalline silicon (100) which is next transformed into a flexible thin sheet of silicon fabric with all the pre-fabricated devices. This process preserves the ultra-high integration density advantage unachievable on other flexible substrates. In addition, the memristive devices are of the size of a motor neuron and the flexible/folded architectural form factor is critical to match brain cortex\\'s folded pattern for ultra-compact design.

  18. Silicon Sensors for Trackers at High-Luminosity Environment

    CERN Document Server

    Peltola, Timo

    2015-01-01

    The planned upgrade of the LHC accelerator at CERN, namely the high luminosity (HL) phase of the LHC (HL-LHC foreseen for 2023), will result in a more intense radiation environment than the present tracking system was designed for. The required upgrade of the all-silicon central trackers at the ALICE, ATLAS, CMS and LHCb experiments will include higher granularity and radiation hard sensors. The radiation hardness of the new sensors must be roughly an order of magnitude higher than the one of LHC detectors. To address this, a massive R&D program is underway within the CERN RD50 collaboration "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" to develop silicon sensors with sufficient radiation tolerance. Research topics include the improvement of the intrinsic radiation tolerance of the sensor material and novel detector designs with benefits like reduced trapping probability (thinned and 3D sensors), maximized sensitive area (active edge sensors) and enhanced charge ...

  19. Surface modification of silicon nanowire field-effect devices with Si-C and Si-N bonded Monolayers

    NARCIS (Netherlands)

    Masood, M.N.

    2011-01-01

    The research work was mainly focused on the surface modification/surface functionalization of active-gate areas of silicon nanowire field-effect transistor devices (Si-NW FET) using hydrogen terminated surfaces, Si-C and Si-N bonded monolayers and subsequent bioimmobilization for biosensor

  20. Computational and Simulation Modeling of Political Attitudes: The 'Tiger' Area of Political Culture Research

    National Research Council Canada - National Science Library

    Voinea, Camelia Florela

    2016-01-01

    ...” – of political culture modeling research. This paper reviews the research literature on the conceptual, computational and simulation modeling of political attitudes developed starting with the beginning of the 20th century until the present times...

  1. Multifunctional optomechanical dynamics in integrated silicon photonics

    Science.gov (United States)

    Li, Huan

    Light can generate forces on matter. The nature of these forces is electromagnetic force, or Lorentz force. The emergence and rapid progress of nanotechnology provided an unprecedented platform where the very feeble optical forces began to play significant roles. The interactions between light and matter in nanoscale has been the focus of almost a decade of active theoretical and experimental investigations, which are still ongoing and constitute a whole new burgeoning branch of nanotechnology, nano-optomechanical systems (NOMS). In such context, the general goal of my research is to generate, enhance and control optical forces on silicon photonics platforms, with a focus on developing new functionalities and demonstrating novel effects, which will potentially lead to a new class of silicon photonic devices for a broad spectrum of applications. In this dissertation, the concept of optical force and the general background of the NOMS research area are first introduced. The general goal of the silicon photonics research area and the research presented in this dissertation is then described. Subsequently, the fundamental theory for optical force is summarized. The different methods to calculate optical forces are enumerated and briefly reviewed. Integrated hybrid plasmonic waveguide (HPWG) devices have been successfully fabricated and the enhanced optical forces experimentally measured for the first time. All-optical amplification of RF signals has been successfully demonstrated. The optical force generated by one laser is used to mechanically change the optical path and hence the output power of another laser. In addition, completely optically tunable mechanical nonlinear behavior has been demonstrated for the first time and systematically studied. Optomechanical photon shuttling between photonic cavities has been demonstrated with a "photon see-saw" device. This photon see-saw is a novel multicavity optomechanical device which consists of two photonic crystal

  2. Area of old-growth forests in California, Oregon, and Washington. Forest Service research bulletin

    Energy Technology Data Exchange (ETDEWEB)

    Bolsinger, C.L.; Waddell, K.L.

    1993-12-01

    An area of old-growth forests in California, Oregon, and Washington has declined significantly in the second half of the 20th century. The report summarizes available information on old-growth forest area by ownership in California, Oregon, and Washington. Old-growth definitions used by the various owners and agencies are provided.

  3. Laser wafering for silicon solar.

    Energy Technology Data Exchange (ETDEWEB)

    Friedmann, Thomas Aquinas; Sweatt, William C.; Jared, Bradley Howell

    2011-03-01

    Current technology cuts solar Si wafers by a wire saw process, resulting in 50% 'kerf' loss when machining silicon from a boule or brick into a wafer. We want to develop a kerf-free laser wafering technology that promises to eliminate such wasteful wire saw processes and achieve up to a ten-fold decrease in the g/W{sub p} (grams/peak watt) polysilicon usage from the starting polysilicon material. Compared to today's technology, this will also reduce costs ({approx}20%), embodied energy, and green-house gas GHG emissions ({approx}50%). We will use short pulse laser illumination sharply focused by a solid immersion lens to produce subsurface damage in silicon such that wafers can be mechanically cleaved from a boule or brick. For this concept to succeed, we will need to develop optics, lasers, cleaving, and high throughput processing technologies capable of producing wafers with thicknesses < 50 {micro}m with high throughput (< 10 sec./wafer). Wafer thickness scaling is the 'Moore's Law' of silicon solar. Our concept will allow solar manufacturers to skip entire generations of scaling and achieve grid parity with commercial electricity rates. Yet, this idea is largely untested and a simple demonstration is needed to provide credibility for a larger scale research and development program. The purpose of this project is to lay the groundwork to demonstrate the feasibility of laser wafering. First, to design and procure on optic train suitable for producing subsurface damage in silicon with the required damage and stress profile to promote lateral cleavage of silicon. Second, to use an existing laser to produce subsurface damage in silicon, and third, to characterize the damage using scanning electron microscopy and confocal Raman spectroscopy mapping.

  4. Research Impact Assessment in Agriculture--A Review of Approaches and Impact Areas

    Science.gov (United States)

    Weißhuhn, Peter; Helming, Katharina; Ferretti, Johanna

    2018-01-01

    Research has a role to play in society's endeavour for sustainable development. This is particularly true for agricultural research, since agriculture is at the nexus between numerous sustainable development goals. Yet, generally accepted methods for linking research outcomes to sustainability impacts are missing. We conducted a review of…

  5. Atomic and electronic structures of novel silicon surface structures

    Energy Technology Data Exchange (ETDEWEB)

    Terry, J.H. Jr.

    1997-03-01

    The modification of silicon surfaces is presently of great interest to the semiconductor device community. Three distinct areas are the subject of inquiry: first, modification of the silicon electronic structure; second, passivation of the silicon surface; and third, functionalization of the silicon surface. It is believed that surface modification of these types will lead to useful electronic devices by pairing these modified surfaces with traditional silicon device technology. Therefore, silicon wafers with modified electronic structure (light-emitting porous silicon), passivated surfaces (H-Si(111), Cl-Si(111), Alkyl-Si(111)), and functionalized surfaces (Alkyl-Si(111)) have been studied in order to determine the fundamental properties of surface geometry and electronic structure using synchrotron radiation-based techniques.

  6. Silicon photonics beyond silicon-on-insulator

    Science.gov (United States)

    Chiles, Jeff; Fathpour, Sasan

    2017-05-01

    The standard platform for silicon photonics has been ridge or channel waveguides fabricated on silicon-on-insulator (SOI) wafers. SOI waveguides are so versatile and the technology built around it is so mature and popular that silicon photonics is almost regarded as synonymous with SOI photonics. However, due to several shortcomings of SOI photonics, novel platforms have been recently emerging. The shortcomings could be categorized into two sets: (a) those due to using silicon as the waveguide core material; and (b) those due to using silicon dioxide as the bottom cladding layer. Several heterogeneous platforms have been developed to address the first set of shortcomings. In such important heterogeneous integrated photonic platforms, the top silicon layer of SOI is typically replaced by a thin film of another optical material with a refractive index higher than the buried oxide (BOX) bottom cladding layer. Silicon is still usually preferred as the substrate of choice, but silicon has no optical functionality. In contrast, the second category of solutions aim at using silicon as the core waveguide material, while resolving issues related to the BOX layer. Particularly, one of the main drawbacks of SOI is that the BOX layer induces high optical loss in the mid-wavelength infrared (mid-IR) range. Accordingly, a host of platforms have been proposed, and some have been demonstrated, in which the BOX is replaced with insulating materials that have low intrinsic loss in the mid-IR. Examples are sapphire, lithium niobate, silicon nitride and air (suspended Si membrane waveguides). Although silicon is still the preferred substrate, sometimes a thin film of silicon, on which the optical waveguide is formed, is directly placed on top of another substrate (e.g., sapphire or lithium niobate). These alternative substrates act as both mechanical support and the lower cladding layer. In addition to the demands of mid-IR photonics, the non-SOI platforms can potentially offer other

  7. The dark side of silicon energy efficient computing in the dark silicon era

    CERN Document Server

    Liljeberg, Pasi; Hemani, Ahmed; Jantsch, Axel; Tenhunen, Hannu

    2017-01-01

    This book presents the state-of-the art of one of the main concerns with microprocessors today, a phenomenon known as "dark silicon". Readers will learn how power constraints (both leakage and dynamic power) limit the extent to which large portions of a chip can be powered up at a given time, i.e. how much actual performance and functionality the microprocessor can provide. The authors describe their research toward the future of microprocessor development in the dark silicon era, covering a variety of important aspects of dark silicon-aware architectures including design, management, reliability, and test. Readers will benefit from specific recommendations for mitigating the dark silicon phenomenon, including energy-efficient, dedicated solutions and technologies to maximize the utilization and reliability of microprocessors. Enables readers to understand the dark silicon phenomenon and why it has emerged, including detailed analysis of its impacts; Presents state-of-the-art research, as well as tools for mi...

  8. Role of Firing Temperature, Sheet Resistance, and Contact Area in Contact Formation on Screen-Printed Metal Contact of Silicon Solar Cell

    Science.gov (United States)

    Ahmad, Samir Mahmmod; Leong, Cheow Siu; Sopian, K.; Zaidi, Saleem H.

    2017-12-01

    Formation of an Ohmic contact requires a suitable firing temperature, appropriate doping profile, and contact dimensions within resolution limits of the screen-printing process. In this study, the role of the peak firing temperature in standard rapid thermal annealing (RTA) six-zone conveyor belt furnace (CBF) and two inexpensive alternate RTA systems [a custom-designed, three-zone, 5″-diameter quartz tube furnace (QTF) and a tabletop, 3″-diameter rapid thermal processing (RTP)] has been investigated. In addition, the role of sheet resistance and contact area in achieving low-resistance ohmic contacts has been examined. Electrical measurements of ohmic contacts between silver paste/n +-emitter layer with varying sheet resistances and aluminum paste/p-doped wafer were carried out in transmission line method configuration. Experimental measurements of the contact resistivity (ρ c) exhibited the lowest values for CBF at 0.14 mΩ cm2 for Ag and 100 mΩ cm2 for Al at a peak firing temperature of 870°C. For the QTF configuration, lowest measured contact resistivities were 3.1 mΩ cm2 for Ag and 74.1 mΩ cm2 for Al at a peak firing temperature of 925°C. Finally, for the RTP configuration, lowest measured contact resistivities were 1.2 mΩ cm2 for Ag and 68.5 mΩ cm2 for Al at a peak firing temperature of 780°C. The measured contact resistivity exhibits strong linear dependence on sheet resistance. The contact resistivity for Ag decreases with contact area, while for Al the opposite behavior is observed.

  9. Silicon nanocrystals and defect states in silicon rich silicon nitride for optoelectronic applications

    Science.gov (United States)

    Mohammed, Shakil

    Research interest in silicon nanocrystals (Si-NC) has increased significantly as a result of the desire to improve the light emission efficiency of bulk silicon. Si-NCs embedded in silicon nitride have desirable characteristics for optoelectronic applications since they can increase the tunneling probability and have a lower tunneling barrier than silicon oxide. Higher tunneling probability is an important feature as it can be used to develop more efficient electroluminescent and photovoltaic devices. In this dissertation, the Si-rich Si3N 4 (SRN) was prepared using low pressure chemical vapor deposition (LPCVD) and RF sputtering followed by high temperature treatment in order to precipitate Si-NCs within the silicon nitride matrix. Several different characterization techniques were used on the Si-NC samples in order to understand the physical, structural, optical and electrical behavior of the nanocrystals. Characterization techniques used in this analysis included photoluminescence (PL), time resolved PL, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, transmission electron microscopy, ellipsometry and capacitance-voltage (C-V) measurements. Silicon nitride was found to contain a high defect density which suppressed the PL effect from the Si-NC. The PL observed from each different SRN sample correlated to defect states, namely dangling bonds and oxygen related bonding. Although substantial evidence suggested that Si-NC had formed within the SRN sample, a PL effect due to the quantum confinement effect (QCE) from the nanocrystals could not be detected. However, Si rich SiOx samples exhibited excellent PL which correlated with the QCE for an indirect bandgap semiconductor. Further experiments were conducted using forming gas in order to passivate the defects in the SRN. Though significant changes in PL was not achieved due to passivation, the electrical behavior from the SRN indicated that the

  10. A decade of research in Inuit children, youth, and maternal health in Canada: areas of concentrations and scarcities

    Directory of Open Access Journals (Sweden)

    Amanda J. Sheppard

    2012-07-01

    Full Text Available Inuit Canadians are on average about 20 years younger and have a 10-year lower life expectancy than other Canadians. While there have been improvements in Inuit health status over time, significant health disparities still remain. This paper will review the peer-reviewed literature related to Inuit child, youth, and maternal health between 2000 and 2010, investigate which thematic areas were examined, and determine what proportion of the research is related to each group. Establishing areas of research concentrations and scarcities may help direct future research where it is needed. We followed a systematic literature review and employed peer-reviewed research literature on child, youth, and maternal health which were selected from 3 sources, MEDLINE, CINAHL, and the Circumpolar Health Bibliographic Database. The resulting references were read, and summarized according to population group and thematic area. The thematic areas that emerged by frequency were: infectious disease; environment/environmental exposures; nutrition; birth outcomes; tobacco; chronic disease; health care; policy, human resources; interventions/programming; social determinants of health; mental health and wellbeing; genetics; injury; and dental health. The 72 papers that met the inclusion criteria were not mutually exclusive with respect to group studied. Fifty-nine papers (82% concerned child health, 24 papers (33% youth health, and 58 papers (81% maternal health. The review documented high incidences of illness and significant public health problems; however, in the context of these issues, opportunities to develop research that could directly enhance health outcomes are explored.

  11. Economic Development Mode and Countermeasure Research on the Nansi Lake Drainage Area Based on Circular Economy

    OpenAIRE

    Jia, Yong-fei; Peng, Li-min

    2011-01-01

    Firstly, it is pointed out that circular economy should be vigorously developed in the Nansi Lake Drainage Area, and the connotation of circular economy is expounded. Then, problems in developing circular economy in Nansi Lake Drainage Area are analyzed from the aspects of agriculture, industrial enterprises, and waste utilization. Finally, combining with the four modes of peasant household, enterprise, region and society in the development of circular economy, corresponding countermeasures a...

  12. Coating of silicon pore optics

    DEFF Research Database (Denmark)

    Cooper-Jensen, Carsten P.; Ackermann, M.; Christensen, Finn Erland

    2009-01-01

    For the International X-ray observatory (IXO), a mirror module with an effective area of 3 m2 at 1.25 keV and at least 0.65 m2 at 6 keV has to be realized. To achieve this goal, coated silicon pore optics has been developed over the last years. One of the challenges is to coat the Si plates...

  13. Silicon photonics III systems and applications

    CERN Document Server

    Lockwood, David

    2016-01-01

    This book is volume III of a series of books on silicon photonics. It reports on the development of fully integrated systems where many different photonics component are integrated together to build complex circuits. This is the demonstration of the fully potentiality of silicon photonics. It contains a number of chapters written by engineers and scientists of the main companies, research centers and universities active in the field. It can be of use for all those persons interested to know the potentialities and the recent applications of silicon photonics both in microelectronics, telecommunication and consumer electronics market.

  14. 1366 Project Silicon: Reclaiming US Silicon PV Leadership

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Adam [1366 Technologies, Bedford, MA (United States)

    2016-02-16

    1366 Technologies’ Project Silicon addresses two of the major goals of the DOE’s PV Manufacturing Initiative Part 2 program: 1) How to reclaim a strong silicon PV manufacturing presence and; 2) How to lower the levelized cost of electricity (“LCOE”) for solar to $0.05-$0.07/kWh, enabling wide-scale U.S. market adoption. To achieve these two goals, US companies must commercialize disruptive, high-value technologies that are capable of rapid scaling, defensible from foreign competition, and suited for US manufacturing. These are the aims of 1366 Technologies Direct Wafer ™ process. The research conducted during Project Silicon led to the first industrial scaling of 1366’s Direct Wafer™ process – an innovative, US-friendly (efficient, low-labor content) manufacturing process that destroys the main cost barrier limiting silicon PV cost-reductions: the 35-year-old grand challenge of making quality wafers (40% of the cost of modules) without the cost and waste of sawing. The SunPath program made it possible for 1366 Technologies to build its demonstration factory, a key and critical step in the Company’s evolution. The demonstration factory allowed 1366 to build every step of the process flow at production size, eliminating potential risk and ensuring the success of the Company’s subsequent scaling for a 1 GW factory to be constructed in Western New York in 2016 and 2017. Moreover, the commercial viability of the Direct Wafer process and its resulting wafers were established as 1366 formed key strategic partnerships, gained entry into the $8B/year multi-Si wafer market, and installed modules featuring Direct Wafer products – the veritable proving grounds for the technology. The program also contributed to the development of three Generation 3 Direct Wafer furnaces. These furnaces are the platform for copying intelligently and preparing our supply chain – large-scale expansion will not require a bigger machine but more machines. SunPath filled the

  15. Sustainability indicators for innovation and research institutes of nuclear area in Brazil; Indicadores de sustentabilidade para institutos de pesquisa e inovacao da area nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Alves, S.F.; Barreto, A.A.; Rodrigues, P.C.H.; Feliciano, V.M.D., E-mail: sfa@cdtn.br, E-mail: aab@cdtn.br, E-mail: pchr@cdtn.br, E-mail: vmfj@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2016-11-01

    Indicators are relevant tools for measuring sustainability process. In this study, the relevance of sustainability indicators appropriate for research and innovation institutes in Brazil is discussed. As reference for case study, nuclear research and innovation institutes were chosen. Sixty-nine sustainability indicators were considered. Some of these indicators were obtained from lists in the literature review, distributed between the dimensions environmental, economic, social, cultural and institutional. The other indicators were developed through discussions between professionals from nuclear, environmental, economic, social and cultural areas. Among the investigated indicators, 32 were selected as being the most relevant. Discrepancies were found during the analysis the opinions of the experts in relation to sustainability dimensions proposed. (author)

  16. Wilderness for science: pros and cons of using wilderness areas for biological research

    Science.gov (United States)

    Diana L. Six; Paul Alaback; Robert A. Winfree; Delia Snyder; Anne Hagele

    2000-01-01

    Research is one of the intended purposes of wilderness. The Wilderness Act states that “wilderness may contain ecological, geological, or other features of scientific, educational, scenic, or historical value.” This session specifically focuses on the pros and cons of conducting research in wilderness.

  17. Peer Observation as teaching evaluation approach: An Attempt to review the research area

    Directory of Open Access Journals (Sweden)

    Michek Stanislav

    2016-01-01

    Full Text Available This review sets out to map research relating to the concept of peer observation when teachers observe lesson of another teacher which is on same level. The review builds on journal papers included in the Web of Science and/or ERIC databases. The study uses documents analysis when the units of analysis are concepts of peer observation, research aims and research methods of studies. The review aims to answer the following questions: What are the objectives of studies focused on peer observation of teacher in the studies? Which methods and approaches do the studies use? What are the results of these studies? The authors conclude the review with a summary of its findings and a discussion. There are a number of research instruments and methods for investigating peer observation by qualitative approach, but the challenge now is to develop ways of quantitative research approach.

  18. [Use of area-level socioeconomic indicators in epidemiological research: experience in Spain and advancement opportunities].

    Science.gov (United States)

    Domínguez-Berjón, María Felicitas; Rodríguez-Sanz, Maica; Marí-Dell'Olmo, Marc; Esnaola, Santiago; Prieto-Salceda, María Dolores; Duque, Ignacio; Rodrigo, María Pilar

    2014-01-01

    To determine the use of area-level socioeconomic indicators in epidemiological studies in Spain. We included studies analyzing the association of area-level socioeconomic indicators and health indicators in Spain published in peer-reviewed journals. An electronic search was conducted in PubMed-Medline, SCI-Expanded, SSCI, Embase, and the Spanish Medical Index (until December 31, 2012). A manual search was also conducted of the references of the selected studies. Each of the articles initially selected on the basis of the title and abstract was reviewed by two investigators. Information was obtained on the publication and methodology (design and study areas, information sources, health and socioeconomic indicators, and statistical analysis). We included 142 studies published since 1988 (58.4% since 2005). More than half (59.9%) were in English. The level of analysis was ecological in 73.2% and multilevel in 19.0%. The areas most frequently analyzed were census tracts (35 studies), especially within cities or autonomous regions, followed by the provinces (30 studies), mostly concerning Spain overall. The dependent variable most frequently analyzed was mortality and the socioeconomic dimension most commonly used was employment (71.1%). In the last decade in Spain, there has been an increase in the number of studies examining the association of area-level socioeconomic and health indicators, as well as in the complexity of design and analysis. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  19. Research capacity for childhood obesity prevention in Latin America: an area for growth.

    Science.gov (United States)

    Parra, Diana C; Vorkoper, Susan; Kohl, Harold W; Caballero, Benjamin; Batis, Carolina; Jauregui, Alejandra; Mason, Jessica; Pratt, Michael

    2017-07-01

    The rise of childhood obesity in Latin America calls for research capacity to understand, monitor and implement strategies, policies and programmes to address it. The objective of the study was to assess current research capacity in Latin America related to childhood obesity, nutrition and physical activity. We conducted a search of peer-reviewed articles on childhood obesity in Latin America with at least one Latin American author from 2010 to May 2015. We coded 484 published articles for author affiliation, study subjects' nationality, research topic and study design and extracted a series of networks per research topic, study design and collaborating country for each of the countries. Obesity is the most frequently explored topic. Nutrition and obesity are somewhat better developed compared with physical activity and sedentary behaviour. There are numerous observational and cross-sectional studies, indicating either a lack of capacity required for more complex research or the extent of the problem and associated factors is still unknown. The low number of intervention studies and the near absence of policy articles suggest a void in research capacity. For childhood obesity, there is a clear need to build research capacity that documents the current state of the problem and design evidence-based prevention and intervention efforts. © 2017 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation.

  20. Mechanically flexible optically transparent silicon fabric with high thermal budget devices from bulk silicon (100)

    KAUST Repository

    Hussain, Muhammad Mustafa

    2013-05-30

    Today’s information age is driven by silicon based electronics. For nearly four decades semiconductor industry has perfected the fabrication process of continuingly scaled transistor – heart of modern day electronics. In future, silicon industry will be more pervasive, whose application will range from ultra-mobile computation to bio-integrated medical electronics. Emergence of flexible electronics opens up interesting opportunities to expand the horizon of electronics industry. However, silicon – industry’s darling material is rigid and brittle. Therefore, we report a generic batch fabrication process to convert nearly any silicon electronics into a flexible one without compromising its (i) performance; (ii) ultra-large-scale-integration complexity to integrate billions of transistors within small areas; (iii) state-of-the-art process compatibility, (iv) advanced materials used in modern semiconductor technology; (v) the most widely used and well-studied low-cost substrate mono-crystalline bulk silicon (100). In our process, we make trenches using anisotropic reactive ion etching (RIE) in the inactive areas (in between the devices) of a silicon substrate (after the devices have been fabricated following the regular CMOS process), followed by a dielectric based spacer formation to protect the sidewall of the trench and then performing an isotropic etch to create caves in silicon. When these caves meet with each other the top portion of the silicon with the devices is ready to be peeled off from the bottom silicon substrate. Release process does not need to use any external support. Released silicon fabric (25 μm thick) is mechanically flexible (5 mm bending radius) and the trenches make it semi-transparent (transparency of 7%). © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  1. Definite Integral Automatic Analysis Mechanism Research and Development Using the "Find the Area by Integration" Unit as an Example

    Science.gov (United States)

    Ting, Mu Yu

    2017-01-01

    Using the capabilities of expert knowledge structures, the researcher prepared test questions on the university calculus topic of "finding the area by integration." The quiz is divided into two types of multiple choice items (one out of four and one out of many). After the calculus course was taught and tested, the results revealed that…

  2. Pediatric Community-Acquired Pneumonia in the United States: Changing Epidemiology, Diagnostic and Therapeutic Challenges, and Areas for Future Research.

    Science.gov (United States)

    Katz, Sophie E; Williams, Derek J

    2018-03-01

    Community-acquired pneumonia (CAP) is one of the most common serious infections in childhood. This review focuses on pediatric CAP in the United States and other industrialized nations, specifically highlighting the changing epidemiology of CAP, diagnostic and therapeutic challenges, and areas for further research. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Hydrogen generation using silicon nanoparticles and their mixtures with alkali metal hydrides

    Science.gov (United States)

    Patki, Gauri Dilip

    Hydrogen is a promising energy carrier, for use in fuel cells, engines, and turbines for transportation or mobile applications. Hydrogen is desirable as an energy carrier, because its oxidation by air releases substantial energy (thermally or electrochemically) and produces only water as a product. In contrast, hydrocarbon energy carriers inevitably produce CO2, contributing to global warming. While CO2 capture may prove feasible in large stationary applications, implementing it in transportation and mobile applications is a daunting challenge. Thus a zero-emission energy carrier like hydrogen is especially needed in these cases. Use of H2 as an energy carrier also brings new challenges such as safe handling of compressed hydrogen and implementation of new transport, storage, and delivery processes and infrastructure. With current storage technologies, hydrogen's energy per volume is very low compared to other automobile fuels. High density storage of compressed hydrogen requires combinations of high pressure and/or low temperature that are not very practical. An alternative for storage is use of solid light weight hydrogenous material systems which have long durability, good adsorption properties and high activity. Substantial research has been conducted on carbon materials like activated carbon, carbon nanofibers, and carbon nanotubes due to their high theoretical hydrogen capacities. However, the theoretical values have not been achieved, and hydrogen uptake capacities in these materials are below 10 wt. %. In this thesis we investigated the use of silicon for hydrogen generation. Hydrogen generation via water oxidation of silicon had been ignored due to slow reaction kinetics. We hypothesized that the hydrogen generation rate could be improved by using high surface area silicon nanoparticles. Our laser-pyrolysis-produced nanoparticles showed surprisingly rapid hydrogen generation and high hydrogen yield, exceeding the theoretical maximum of two moles of H2 per

  4. Microstructure Control of Columnar-Grained Silicon Substrate Solidified from Silicon Melts Using Gas Pressure

    Directory of Open Access Journals (Sweden)

    Jun-Kyu Lee

    2015-01-01

    Full Text Available A silicon substrate with the dimensions of 100 × 140 × 0.3 mm was grown directly from liquid silicon with gas pressure. The silicon melt in the sealed melting part was injected into the growth part at applied pressure of 780–850 Torr. The solidified silicon substrate was then transferred by the pull of the cooled dummy bar. A desirable structure with a liquid-solid interface perpendicular to the pulling direction was formed when the mold temperature in the solidification zone of the growth part was much higher than that of the dummy bar, as this technique should be able to overcome thermal loss through the molds and the limited heat flux derived from the very narrow contact area between the silicon melt and the dummy bar. In addition, because the metallic impurities and expansion of volume during solidification are preferably moved to a liquid phase, a high-quality silicon substrate, without defects such as cracks and impurities in the substrate, could be manufactured in the interface structure. The present study reports the experimental findings on a new and direct growth system for obtaining silicon substrates characterized by high quality and productivity, as a candidate for alternate routes for the fabrication of silicon substrates.

  5. Recent research efforts in the area of biotechnology for fuels and chemicals: Poster session papers

    Energy Technology Data Exchange (ETDEWEB)

    Antonopoulos, A.A. (Argonne National Lab., IL (United States)); Grohmann, K. (US Citrus and Subtropical Products Lab., Winter Haven, FL (United States))

    1992-01-01

    This report presents research presented at the poster session of the Symposium covering a wide spectrum of current biotechnological research activities. Research focused mostly on ethanol production and methane generation from biomass material via microbial processing, as well as on enhanced hydrogen yield from algae. Several of the posters dealt with the pretreatment of cellulosic materials, and enzyme production/characterization, while a good number of papers displayed research efforts on bioremediation, photosynthesis, production of various useful chemicals from biomass by bioprocessing, and on other miscellaneous subjects. One of the papers treated a very interesting topic of cellulose-cellulase complexes. Many of the poster papers are included in this volume, and a synopsis of all the poster/papers presented is the subject of this article.

  6. Recent research efforts in the area of biotechnology for fuels and chemicals: Poster session papers

    Energy Technology Data Exchange (ETDEWEB)

    Antonopoulos, A.A. [Argonne National Lab., IL (United States); Grohmann, K. [US Citrus and Subtropical Products Lab., Winter Haven, FL (United States)

    1992-09-01

    This report presents research presented at the poster session of the Symposium covering a wide spectrum of current biotechnological research activities. Research focused mostly on ethanol production and methane generation from biomass material via microbial processing, as well as on enhanced hydrogen yield from algae. Several of the posters dealt with the pretreatment of cellulosic materials, and enzyme production/characterization, while a good number of papers displayed research efforts on bioremediation, photosynthesis, production of various useful chemicals from biomass by bioprocessing, and on other miscellaneous subjects. One of the papers treated a very interesting topic of cellulose-cellulase complexes. Many of the poster papers are included in this volume, and a synopsis of all the poster/papers presented is the subject of this article.

  7. Review of Occupational Therapy Research in the Practice Area of Children and Youth

    Science.gov (United States)

    Bendixen, Roxanna M.; Kreider, Consuelo M.

    2011-01-01

    A systematic review was conducted focusing on articles in the Occupational Therapy (OT) practice category of Childhood and Youth (C&Y) published in the American Journal of Occupational Therapy (AJOT) over the two-year period of 2009–2010. The frameworks of the International Classification of Functioning, Disability and Health (ICF) and Positive Youth Development (PYD) were used to explore OT research progress toward the goals of the Centennial Vision (CV). Forty-six research articles were organized by research type and were classified within these two frameworks. The majority of reviewed published research investigated variables representing constructs falling within the ICF domains of Body Functioning and Activity. The effect of OT interventions on PYD resided primarily in building competence. In order to meet the tenets of the CV, OTs must document changes in children’s engagement in everyday life situations and build the evidence of OT’s efficacy in facilitating participation. PMID:21675342

  8. What are Agricultural Economics Ph.D. Students Learning about Agribusiness Research Methods and Subject Areas

    National Research Council Canada - National Science Library

    Lisa House; James Sterns

    2003-01-01

    .... This ambiguity not only limits any assessment of agribusiness Ph.D.-level training, but also undermines the academic endeavors of those interested in pursuing agribusiness-focused research and graduate instruction...

  9. Informed consent for research involving people with dementia: a grey area.

    Science.gov (United States)

    Cubit, Katrina

    2010-01-01

    Research involving people with dementia has been flagged as a key priority by Alzheimer's International. Dementia has been an Australian National Health Priority since 2005, yet there are no clear guidelines for seeking and obtaining informed consent from people with dementia to participate in observational research. Informed consent is an ethical requirement for the conduct of research involving humans. Although many people with dementia are able to express a desire to be involved in research, the insidious progression of the disease reduces a person's ability to understand and appreciate the consequences of involvement. This paper explores the author's journey of seeking and obtaining informed consent for a mixed methods study which involved the observation of older people with dementia.

  10. Research, demonstration, and extension: the ARS area-wide ecologically based invasive plant management project

    Science.gov (United States)

    The Area-wide project is a collaborative five year effort funded in 2008 by USDA-ARS that has brought together scientists with the USDA-ARS, universities, land managers, and policy makers throughout the Great Basin. A primary goal of the project is to develop and implement a comprehensive, regional...

  11. Family Law Proceedings, Domestic Violence and the Impact upon School: A Neglected Area of Research

    Science.gov (United States)

    Eriksson, Maria; Bruno, Linnea; Nasman, Elisabet

    2013-01-01

    The aim of this article is to open up a discussion about an unexplored area of children's lives at school. While there has been considerable discussion of issues about child protection and the cooperation between school and social services in that context, studies on the intersection between school and family law proceedings seem virtually…

  12. Will business cycles in the euro area converge? A critical survey of empirical research

    NARCIS (Netherlands)

    de Haan, J.; Inklaar, R.; Jong-A-Pin, R.

    This survey of business cycle synchronization in the European monetary union focuses on two issues: have business cycles become more similar, and which factors drive business cycle synchronization. We conclude that business cycles in the euro area have gone through periods of both convergence and

  13. Priority research areas to accelerate the development of practical ultraconductive copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dominic F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burwell, Malcolm [International Copper Association, Washington, DC (United States); Stillman, H. [International Copper Association, Washington, DC (United States)

    2015-09-01

    This report documents the findings at an Ultraconductive Copper Strategy Meeting held on March 11, 2015 in Washington DC. The aim of this meeting was to bring together researchers of ultraconductive copper in the U.S. to identify and prioritize critical non-proprietary research activities that will enhance the understanding in the material and accelerate its development into practical conductors. Every effort has been made to ensure that the discussion and findings are accurately reported in this document.

  14. Research for Preseismic Phenomena on the Underground Water Level and Temperature in Selected Areas of Greece

    Science.gov (United States)

    Contadakis, M. E.; Asteriadis, G.

    1997-08-01

    A comprehensive study of the tectonic activity require the contribution of a variety of methods, geological, seismic, geodetic, satellite etc., being currently available in our days. On the other hand, the risk evaluation in areas of high seismicity, like this one of the South Balkan Peninsula, is of vital importance. To this purpose an interdisciplinary following up of the tectonic activity in the area may provide the best provision to the administration for an effective confrontation and intervention for the elimination of the possible disastrous effects in human life cost, financial and social cost of the communities, to which may result a strong earthquake. Among the various methods of indirect monitoring of the tectonic activity in an area, which in addition is of a low cost, is that of the following up of the underground water level and temperature changes in the area of interest. This method is based on the fact that tectonic activity is expected to result to tectonic stresses producing alterations to the local water table which in its turn is expected is expected to be observed as variation of the underground water level and temperature. The method of the following up of the underground water and temperature changes has been applied, among others by the Department of Geodesy and Surveying of the University of Thessaloniki in two areas of high seismicity in Greece: (a) The seismic zone of the lake Volvi in North Greece (40.5 deg N and 23.5 deg E) for ten years (1983-1992) and (b) the area of South Thessaly (39.2 deg N and 21 deg E) for three years (1994-1996). The statistical analysis of the observations, shows that the low frequency constituent (Sa,Ssa,Mf,Mm) of the earth tides and the barometric pressure have a small influence on the water level measurements. The shallow underground water network of South Thessaly is more sensitive to the non tectonic factors than the network of Volvi. Tentative correlation of the underground wat! er and temperature

  15. Sampling Artifacts from Conductive Silicone Tubing

    Energy Technology Data Exchange (ETDEWEB)

    Timko, Michael T.; Yu, Zhenhong; Kroll, Jesse; Jayne, John T.; Worsnop, Douglas R.; Miake-Lye, Richard C.; Onasch, Timothy B.; Liscinsky, David; Kirchstetter, Thomas W.; Destaillats, Hugo; Holder, Amara L.; Smith, Jared D.; Wilson, Kevin R.

    2009-05-15

    We report evidence that carbon impregnated conductive silicone tubing used in aerosol sampling systems can introduce two types of experimental artifacts: 1) silicon tubing dynamically absorbs carbon dioxide gas, requiring greater than 5 minutes to reach equilibrium and 2) silicone tubing emits organic contaminants containing siloxane that adsorb onto particles traveling through it and onto downstream quartz fiber filters. The consequence can be substantial for engine exhaust measurements as both artifacts directly impact calculations of particulate mass-based emission indices. The emission of contaminants from the silicone tubing can result in overestimation of organic particle mass concentrations based on real-time aerosol mass spectrometry and the off-line thermal analysis of quartz filters. The adsorption of siloxane contaminants can affect the surface properties of aerosol particles; we observed a marked reduction in the water-affinity of soot particles passed through conductive silicone tubing. These combined observations suggest that the silicone tubing artifacts may have wide consequence for the aerosol community and should, therefore, be used with caution. Gentle heating, physical and chemical properties of the particle carriers, exposure to solvents, and tubing age may influence siloxane uptake. The amount of contamination is expected to increase as the tubing surface area increases and as the particle surface area increases. The effect is observed at ambient temperature and enhanced by mild heating (<100 oC). Further evaluation is warranted.

  16. Core-shell silicon nanowire solar cells.

    Science.gov (United States)

    Adachi, M M; Anantram, M P; Karim, K S

    2013-01-01

    Silicon nanowires can enhance broadband optical absorption and reduce radial carrier collection distances in solar cell devices. Arrays of disordered nanowires grown by vapor-liquid-solid method are attractive because they can be grown on low-cost substrates such as glass, and are large area compatible. Here, we experimentally demonstrate that an array of disordered silicon nanowires surrounded by a thin transparent conductive oxide has both low diffuse and specular reflection with total values as low as nanowire facilitates enhancement in external quantum efficiency using two different active shell materials: amorphous silicon and nanocrystalline silicon. As a result, the core-shell nanowire device exhibits a short-circuit current enhancement of 15% with an amorphous Si shell and 26% with a nanocrystalline Si shell compared to their corresponding planar devices.

  17. Geografski pristopi k proučevanju kriznih območij = Geographical attempts to research of crisis areas

    Directory of Open Access Journals (Sweden)

    Jernej Zupančič

    2006-01-01

    Full Text Available The paper deals on the phenomenon of crisis areas in the world in the light of international relations in transformation of world political map. Analysing the physiognomy, structures and functions the paper is seeking the reasons for the confl icts, describe their genesis, characteristical developmental stages and particulary the spatial and social consequences. Those mostly regenerate their confl ictual potential and are relatively constant geopolitcial neuralgic areas. They are the crossroads of world-power interesses, even they are poor world periphery by their structure. The paper undertake the geographic point of research of crisis areas. The shown cases of North Dalmatia (Croatia and Kosovo (South Serbia the author ilustrate the characteristical development of two different crisis areas.

  18. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-08-06

    Aug 6, 2015 ... permanent contraceptive methods and women's education (AOR=1.72, 95%CI = 1.02 - 3.05), women's occupation (AOR = 2.01, 95% CI = 1.11 -. 3.58), number of live .... NGO's and presence of different Medias in the area. The result of this .... Social and Behavior Change Communication. Research Brief.

  19. Research

    African Journals Online (AJOL)

    acquire public health, clinical, and/or research skills, usually through applied learning in a community setting,[1] with goals that include: creating knowledge, skills and attitudes among students to ensure they are capable of providing high- quality health services to local, underserved communities, often in rural areas.

  20. Research

    African Journals Online (AJOL)

    abp

    2016-05-13

    May 13, 2016 ... based study that enrolled breast cancer patients from catchment area of an oncology service hospital in Nigeria between 2007 and 2013. ... ISSN: 1937- 8688 (www.panafrican-med-journal.com). Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net). Research.

  1. Research

    African Journals Online (AJOL)

    2014-05-02

    May 2, 2014 ... the quality of graduates and providing them with the necessary skills and competencies to ... However, most of the aforementioned evaluation studies focus on the training process .... except two areas, i.e. X-ray image interpretation and research skills. All 72 respondents ... Ultrasound. Mammography.

  2. Research and Development in the Energy Area; Forskning och utveckling inom energiomraadet. Resultatredovisning 2003

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Anita; Lundborg, Anna; Lundqvist, David; Westin, Paul; Oefverbeck, Lena; Aafelt, Sten

    2003-01-01

    The report gives a review of the Swedish energy research and how it has developed since 1975. In this period 1,200 million SEK (about 150 million USD) has been spent on governmentally funded energy research (excluding the supplementary financing by the businesses). The criteria used in evaluation and follow-up are reported, and the usefulness, efficiency and quality of energy research to society are discussed. Five case-studies are described, showing which factors are important in the development and giving insight in the process of technology development from research, development and demonstration up to market introduction. Beside the case-studies, a short review of the research connected with buildings is given. The case-studies are: Biofuel-based energy systems, Transport (Biofuels, Efficient engines, Electric drives), Power production and Power technology (Hydro power, Wind power, Solar cells, Power transmission and distribution), Industry (Energy efficient metal and paper processes), Support systems - fans, pumps, compressed air and lighting, Buildings (Heating, Cooling, Lighting)

  3. Knowledge production status of Iranian researchers in the gastric cancer area: based on the medline database.

    Science.gov (United States)

    Ghojazadeh, Morteza; Naghavi-Behzad, Mohammad; Nasrolah-Zadeh, Raheleh; Bayat-Khajeh, Parvaneh; Piri, Reza; Mirnia, Keyvan; Azami-Aghdash, Saber

    2014-01-01

    Scientometrics is a useful method for management of financial and human resources and has been applied many times in medical sciences during recent years. The aim of this study was to investigate the status of science production by Iranian scientists in the gastric cancer field based on the Medline database. In this descriptive-cross sectional study Iranian science production concerning gastric cancer during 2000-2011 was investigated based on Medline. After two stages of searching, 121 articles were found, then we reviewed publication date, authors names, journal title, impact factor (IF), and cooperation coefficient between researchers. SPSS.19 was used for statistical analysis. There was a significant increase in published articles about gastric cancer by Iranian researchers in Medline database during 2006-2011. Mean cooperation coefficient between researchers was 6.14±3.29 person per article. Articles of this field were published in 19 countries and 56 journals. Those basex in Thailand, England, and America had the most published Iranian articles. Tehran University of Medical Sciences and Mohammadreza Zali had the most outstanding role in publishing scientific articles. According to results of this study, improving cooperation of researchers in conducting research and scientometric studies about other fields may have an important role in increasing both quality and quantity of published studies.

  4. Camera Calibration for Water-Biota Research: The Projected Area of Vegetation

    Directory of Open Access Journals (Sweden)

    Rene Wackrow

    2015-12-01

    Full Text Available Imaging systems have an indisputable role in revealing vegetation posture under diverse flow conditions, image sequences being generated with off the shelf digital cameras. Such sensors are cheap but introduce a range of distortion effects, a trait only marginally tackled in hydraulic studies focusing on water-vegetation dependencies. This paper aims to bridge this gap by presenting a simple calibration method to remove both camera lens distortion and refractive effects of water. The effectiveness of the method is illustrated using the variable projected area, computed for both simple and complex shaped objects. Results demonstrate the significance of correcting images using a combined lens distortion and refraction model, prior to determining projected areas and further data analysis. Use of this technique is expected to increase data reliability for future work on vegetated channels.

  5. [Textual research on the origin and producing area of Baitouweng (Radix Pulsatillae)].

    Science.gov (United States)

    Wang, W H; Zhan, Z L; Peng, H S; Yang, J; Qian, J P

    2017-01-28

    Baitouweng (Pulsatilla Root), a commonly used traditional Chinese medicine, was first recorded in Shen nong ben cao jing (Shennong's Classic of Materia Medica) . Pulsatilla chinensis (Bunge) Regel from Ranunculaceae had become the authentic source for the Baitouweng since the Song Dynasty, which was consistent with the Radix Pulsatillae collected in the Chinese Pharmacopoeia. Chuzhou, Anhui province, being regarded as the main producing area in ancient times, had been its genuine producing area since the period of Republic of China. From the Tang Dynasty to Ming Dynasty, the origin of Baitouweng recorded in the works of Chinese materia medica could also include P. cernua, P. dahurica and P. ambigua. Therefore, P. chinensis in Chuzhou, with large quantity and high quality, is a superior resource that need to increase its protection and further studies, whereas P. cernua, P. dahurica and P. ambigua have better to be used as local drugs.

  6. Camera Calibration for Water-Biota Research: The Projected Area of Vegetation.

    Science.gov (United States)

    Wackrow, Rene; Ferreira, Edgar; Chandler, Jim; Shiono, Koji

    2015-12-03

    Imaging systems have an indisputable role in revealing vegetation posture under diverse flow conditions, image sequences being generated with off the shelf digital cameras. Such sensors are cheap but introduce a range of distortion effects, a trait only marginally tackled in hydraulic studies focusing on water-vegetation dependencies. This paper aims to bridge this gap by presenting a simple calibration method to remove both camera lens distortion and refractive effects of water. The effectiveness of the method is illustrated using the variable projected area, computed for both simple and complex shaped objects. Results demonstrate the significance of correcting images using a combined lens distortion and refraction model, prior to determining projected areas and further data analysis. Use of this technique is expected to increase data reliability for future work on vegetated channels.

  7. Building the nordic research and innovation areas in hydrogen. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    Dannemand Andersen, P.; Holst Joergensen, B. [Risoe National Lab., System Analysis Dept., Roskilde (Denmark); Eerola, A.; Koljonen, T.; Loikkanen, T. [VTT Information Service, Espoo (Finland); Eriksson, E.A. [FOI, Stockholm (SE)] (eds.)

    2005-01-01

    The Nordic Hydrogen Energy Foresight was launched in January 2003 by 16 partners from academia, industry, energy companies and associations from all five Nordic countries. A wide range of additional Nordic and European experts from research, industry and governments have participated in the various steps of the foresight process. The aim of the foresight is to provide decision support for companies and research institutes in defining R and D priorities and to assist governmental decision-makers in making effective framework policies for the introduction of hydrogen energy. The foresight exercise also provides a means for developing Nordic networks to gain critical mass in a wider international context. Interaction between research, industry and government, and combination of judgemental and formal procedures are essential features of the Nordic H{sub 2} Energy Foresight. The foresight process includes a series of pre-structured interactive workshops, supported by systems analysis and assessment of technical developments. (BA)

  8. Influence of changes in crop cultivation areas on pollen contents of honey (Research Note

    Directory of Open Access Journals (Sweden)

    A.-L. VARIS

    2008-12-01

    Full Text Available Pollen counts were done on honey collected by a Finnish honey corporation in late summer 1997 from the entire beekeeping area of Finland. The most common pollen type was Brassicaceae pollen, which was represented by 60% of the grains counted. It was followed by Salix spp. (10%, Trifolium repens + T. hybridum (10% and T. pratense + T. medium (6.5% species. Pollen grains of Phacelia spp, Filipendula ulmaria, Apiaceae, Sorbus aucuparia, Malus domestica, and Rubus idaeus were also numerous. These pollen types constituted 96% of all the pollen examined. These results and those of the earlier pollen counts in Finland were compared with the cultivation areas of the most important nectariferous crops. In the 1930s white clover was the most important honey source in Finland and its pollen was very dominant in honey. Since the 1950s oilseed crops have been grown in increasing rates and pure timothy-meadow fescue pastures and hay stands with heavy N applications have decreased the share of Trifolium species. The proportion of Brassicaceae pollen has continuously increased with the increase of the growing area of turnip rape Brassica rapa ssp. oleifera and rape, B. napus ssp. oleifera. At the same time the proportion of T. repens + T. hybridum pollen has decreased so that their mutual relationships are now reversed compared to the beginning of the 1960s. Changes in land use were thus very clearly to be seen in the pollen content of honey.;

  9. Recent trends in rural Geography studies. Theoretical developments and research areas in Latin America

    Directory of Open Access Journals (Sweden)

    Héctor Ávila Sánchez

    2015-12-01

    Full Text Available In this paper it is made a tour through the various theoretical and methodological routes that support the Rural Geography, in its current forms. The article is part of a wider investigation into the trends and state of the art of rurality between the years 1990 and 2010, with emphasis on rural geography perspective and particularly on the contributions that establish French geography and Anglo-Saxon geography. It highlights how these influences have transcended national geographical schools in some countries of Latin America. At the beginning of the discipline in the early twentieth century, emphasizing the identification and description of landscapes, influenced by the importance of regionalist discourse. Subsequently, rural geographical studies developed under the influence of economic geography, mainly describing large areas of agricultural specialization worldwide (cereal production areas, or Mediterranean agriculture, etc.. Later, from the decade of the eighties, analyze the depth of the territorial changes that occur in rural areas, due to changes in the Fordist and post-Fordist production paradigm, and the arrangements resulting from globalization.

  10. WAS LUXURY LITTLE RESEARCHED? AN EXPLORATION OF STUDIES AND RESEARCH TRENDS IN THE AREA OF MARKETING OF LUXURY GOODS, BEFORE 2005

    Directory of Open Access Journals (Sweden)

    Raluca CIORNEA

    2012-01-01

    Full Text Available The first questions that all scientists address when approaching a new domain are related to how well studied is the field, who and what has studied. The answers help them establish their personal areas of interest and contribution. Thus in order to help the authors concerned with the luxury domain we decided to conduct a secondary marketing research and the main purpose was to identify the studies and the trends in research in the area of marketing of luxury goods and their degree of approach, before 2005. The present study is only a part of a complex research that approaches the entire evolution in luxury research field, but due to space limitation papers were separated in two: the evolution before 2005 and the evolution after 2005. Unique by its theme, this paper is intended to be ambitious by analysing all the luxury materials to which had access the authors The results confirmed the previous statement of some authors that luxury was little researched comparing to other domains.

  11. Liquid Silicon Pouch Anode

    Science.gov (United States)

    2017-09-06

    Docket No. 300139 1 of 13 LIQUID SILICON POUCH ANODE STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured... silicon -based anodes during cycling, lithium insertion and deinsertion. Mitigation of this problem has long been sought and will result in improved...with other potential lithium alloy materials such as gallium and tin. Silicon -based solid state anodes are typically composed of small particles of

  12. Silicon spin communication

    OpenAIRE

    Dery, Hanan; Song, Yang; Li, Pengke; Zutic, Igor

    2011-01-01

    Recent experimental breakthroughs have demonstrated that the electron spin in silicon can be reliably injected and detected as well as transferred over distances exceeding 1 mm. We propose an on-chip communication paradigm which is based on modulating spin polarization of a constant current in silicon wires. We provide figures of merit for this scheme by studying spin relaxation and drift-diffusion models in silicon.

  13. Handbook of silicon photonics

    CERN Document Server

    Pavesi, Lorenzo

    2013-01-01

    The development of integrated silicon photonic circuits has recently been driven by the Internet and the push for high bandwidth as well as the need to reduce power dissipation induced by high data-rate signal transmission. To reach these goals, efficient passive and active silicon photonic devices, including waveguide, modulators, photodetectors, multiplexers, light sources, and various subsystems, have been developed that take advantage of state-of-the-art silicon technology.

  14. Charities' response to the European Commission call of interest for their involvement in the European Research Area

    CERN Document Server

    Sessano, D.

    2003-01-01

    This paper presents an exploratory study to investigate what could be the role of the charities concerned with scientific research in the European Research Area (ERA). The analysis particularly concentrates on UK and Italy. The questions on which the exploratory study was developed are: 1. “In what specific areas of the ERA did the European Commission (EC) for the involvement of charities? And could there be other areas in which charities might participate?” 2. “Given the role and situation of charities in UK and Italy, what role, if any, could they be willing to play in the ERA? Is it the same as the one proposed by the Commission or not?” In order to answer these questions, the following discussion will focus at first on a short overview of the charity sector, both at the general level and at the national level in UK and Italy. Then a brief presentation of the European Research Area will be given. The hypotheses of the study will then be presented, followed by a methodological section. Results wi...

  15. Analysis of the production of scientific literature in clinical research areas in Physiotherapy between 2005 and 2009

    Directory of Open Access Journals (Sweden)

    Torres-Narváez Martha

    2012-04-01

    Full Text Available Objective: characterize the behavior of clinical research in Physiotherapy, through the analysis of theproduction of scientific literature in a period of five years in order to identify areas of concentrationand dispersion, collaborative research and types of clinical studies have conducted. Methods andmaterials: descriptive study on the papers in Medline/PubMed from 2005-2009. Were considereda total 404 publications, clinical trials and epidemiological studies side, analyzed according to thepercentage distribution of articles by clinical area, year of publication, and institutional affiliation ofresearchers. Results: It found a greater number of trials (93% systematic reviews represented thegreatest number of epidemiological studies side. The clinical areas pulmonary and cardiovascularaccount for 65% of scientific publications in the studies analyzed. The year with highest numberof publications was 2008. Half of the clinical research produced in this five-year have affiliationwith academic institutions, and secondly, studies conducted in hospitals. Conclusions: the clinicalresearch publications in Physiotherapy in Medline/PubMed registered show sustained activity ofscientific production in the pulmonary and cardiovascular areas, consistent with the major healthconcerns in the world. The findings suggest that the ability of physiotherapists to develop qualityresearch, use and transfer of results into clinical practice should achieve greater development.

  16. Modulation Doping of Silicon using Aluminium-induced Acceptor States in Silicon Dioxide

    Science.gov (United States)

    König, Dirk; Hiller, Daniel; Gutsch, Sebastian; Zacharias, Margit; Smith, Sean

    2017-01-01

    All electronic, optoelectronic or photovoltaic applications of silicon depend on controlling majority charge carriers via doping with impurity atoms. Nanoscale silicon is omnipresent in fundamental research (quantum dots, nanowires) but also approached in future technology nodes of the microelectronics industry. In general, silicon nanovolumes, irrespective of their intended purpose, suffer from effects that impede conventional doping due to fundamental physical principles such as out-diffusion, statistics of small numbers, quantum- or dielectric confinement. In analogy to the concept of modulation doping, originally invented for III-V semiconductors, we demonstrate a heterostructure modulation doping method for silicon. Our approach utilizes a specific acceptor state of aluminium atoms in silicon dioxide to generate holes as majority carriers in adjacent silicon. By relocating the dopants from silicon to silicon dioxide, Si nanoscale doping problems are circumvented. In addition, the concept of aluminium-induced acceptor states for passivating hole selective tunnelling contacts as required for high-efficiency photovoltaics is presented and corroborated by first carrier lifetime and tunnelling current measurements. PMID:28425460

  17. Methodological aspects of paleo-ecological diatom research in coastal areas of the Netherlands

    NARCIS (Netherlands)

    Vos, P.C.; Wolf, H. de

    2007-01-01

    A major problem in paleo-ecological research of diatoms in tidal environments is the distinction of autochthonous and allochthonous diatom valves. A new approach applying several diatom- and non-diatomrelated criteria is introduced in order to solve the autochthonous/allochthonous problem. A

  18. Research-Based Interventions in the Area of Proof: The Past, the Present, and the Future

    Science.gov (United States)

    Stylianides, Gabriel J.; Stylianides, Andreas J.

    2017-01-01

    The concept of "proof" has attracted considerable research attention over the past decades in part due to its indisputable importance to the discipline of mathematics and to students' learning of mathematics. Yet, the teaching and learning of proof is an instructionally arduous territory, with proof being recognized as a hard-to-teach…

  19. Communicating Climate Change through Place Based Engagement: Methods, Research, and Applications to Parks and Protected Area

    Science.gov (United States)

    Davis, Shawn Kyle

    2014-01-01

    This research explored the connections between place attachment and resident perceptions of tourism. Aspects of place attachment such as place identity and place dependence were tested against tourism dependence for strength of correlation and relationship to perceived impacts of tourism. Survey data were collected from residents of eight…

  20. A Survey of the High-Speed Self-Learning Intrusion Detection Research Area

    NARCIS (Netherlands)

    Sperotto, Anna; van de Meent, R.; Bandara, Arosha K.; Burgess, Mark

    Intrusion detection for IP networks has been a research theme for a number of years already. One of the challenges is to keep up with the ever increasing Internet usage and network link speeds, as more and more data has to be scanned for intrusions. Another challenge is that it is hardly feasible to

  1. Energy Drinks: Topical Domain in the Emerging Literature and Neglected Areas of Research

    Science.gov (United States)

    Piotrowski, Chris

    2014-01-01

    Prevalence statistics indicate that consumption of Energy drinks (EDs), often in combination with alcohol, is quite popular in the younger generation and particularly with college students. As literature on this topic is advancing at a rapid pace, it seemed instructive to examine which topics are emphasized in emerging EDs research. To that end, a…

  2. Conception of vadose zone research in the area of Goczałkowice reservoir.

    Science.gov (United States)

    Czekaj, Joanna; Trepka, Kamil

    2013-09-01

    Goczałkowice reservoir is one of the main source of drinking water for Upper Silesia Region. In reference to Water Frame Directive matter since 2010 the strategic research project: "Integrated system supporting management and protection of dammed reservoir (ZiZoZap)”, which is being conducted on Goczałkowice reservoir, has been pursued. In the framework of this project complex groundwater monitoring is carried on. One aspect is vadose zone research, conducted to obtain information about changes in chemical composition of infiltrating water and mass transport within this zone. Based on historical data and the structural model of direct catchment of Goczałkowice reservoir location of the vadose zone research site was selected. At the end of November 2012 specially designed lysimeter was installed with 10 MacroRhizon samplers at each lithological variation in unsaturated zone. This lysimeter, together with nested observation wells, located in the direct proximity, create the vadose zone research site which main aim is specifying the amount of nitrate transport in the vertical profile.

  3. Silicon web process development

    Science.gov (United States)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Skutch, M. E.; Driggers, J. M.; Hopkins, R. H.

    1981-01-01

    The silicon web process takes advantage of natural crystallographic stabilizing forces to grow long, thin single crystal ribbons directly from liquid silicon. The ribbon, or web, is formed by the solidification of a liquid film supported by surface tension between two silicon filaments, called dendrites, which border the edges of the growing strip. The ribbon can be propagated indefinitely by replenishing the liquid silicon as it is transformed to crystal. The dendritic web process has several advantages for achieving low cost, high efficiency solar cells. These advantages are discussed.

  4. Assembly of europium organic framework–gold nanoparticle composite thin films on silicon substrate

    Energy Technology Data Exchange (ETDEWEB)

    Deep, Akash, E-mail: dr.akashdeep@gmail.com [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India); Kaur, Rajnish [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India); Kumar, Parveen [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Kumar, Pawan; Paul, A.K. [Central Scientific Instruments Organisation (CSIR-CSIO), Sector 30 C, Chandigarh 160030 (India); Academy of Scientific and Innovative Research, CSIR-CSIO, Sector 30 C, Chandigarh 160030 (India)

    2014-08-28

    Metal organic frameworks are a sub-class of coordination polymers and rapidly generating huge research interests in several technological areas. One of the emerging areas of their potential applications is the photovoltaics. The present study proposes the assembly of europium organic framework–gold nanoparticle nanocomposite thin film on silicon substrate. Microscopic, X-ray diffraction, surface area measurement and thermal studies have indicated the formation of the desired thin film. Spectral studies have been used to highlight their solid state optical property. Current–voltage studies have established semiconducting property of the above thin films. - Highlights: • Thin film of europium organic framework/gold nanoparticles is prepared on silicon. • Fairly homogeneous films with a roughness factor of 5–10 nm are obtained. • Above thin films offer solid-state photoluminescence and semiconducting properties.

  5. III-V semiconductor devices integrated with silicon III-V semiconductor devices integrated with silicon

    Science.gov (United States)

    Hopkinson, Mark; Martin, Trevor; Smowton, Peter

    2013-09-01

    The integration of III-V semiconductor devices with silicon is one of the most topical challenges in current electronic materials research. The combination has the potential to exploit the unique optical and electronic functionality of III-V technology with the signal processing capabilities and advanced low-cost volume production techniques associated with silicon. Key industrial drivers include the use of high mobility III-V channel materials (InGaAs, InAs, InSb) to extend the performance of Si CMOS, the unification of electronics and photonics by combining photonic components (GaAs, InP) with a silicon platform for next-generation optical interconnects and the exploitation of large-area silicon substrates and high-volume Si processing capabilities to meet the challenges of low-cost production, a challenge which is particularly important for GaN-based devices in both power management and lighting applications. The diverse nature of the III-V and Si device approaches, materials technologies and the distinct differences between industrial Si and III-V processing have provided a major barrier to integration in the past. However, advances over the last decade in areas such as die transfer, wafer fusion and epitaxial growth have promoted widespread renewed interest. It is now timely to bring some of these topics together in a special issue covering a range of approaches and materials providing a snapshot of recent progress across the field. The issue opens a paper describing a strategy for the epitaxial integration of photonic devices where Kataria et al describe progress in the lateral overgrowth of InP/Si. As an alternative, Benjoucef and Reithmaier report on the potential of InAs quantum dots grown direct onto Si surfaces whilst Sandall et al describe the properties of similar InAs quantum dots as an optical modulator device. As an alternative to epitaxial integration approaches, Yokoyama et al describe a wafer bonding approach using a buried oxide concept, Corbett

  6. Model endophenotype for bipolar disorder: Qualitative Analysis, etiological factors, and research areas

    Directory of Open Access Journals (Sweden)

    Naraiana de Oliveira Tavares

    2014-12-01

    Full Text Available The aim of this study is to present an updated view of the writings on the endophenotype model for bipolar disorder using analytical methodologies. A review and analysis of networks was performed through descriptors and keywords that characterize the composition of the endophenotype model as a model of health. Information was collected from between 1992 and 2014, and the main thematic areas covered in the articles were identified. We discuss the results and question their cohesion, emphasizing the need to strengthen and identify the points of connection between etiological factors and characteristics that make up the model of endophenotypes for bipolar disorder.

  7. [Field research on third-world immigrants in the Trento area].

    Science.gov (United States)

    Borzaga, C; Renzetti, E; Covi, L

    1993-06-01

    "The main findings of three empirical [surveys] conducted in the province of Trento [Italy] are presented with a view to gain knowledge about...quantitative aspects...socio-anthropological characteristics and the impact of immigrants from non-European countries on the local economic structure. These findings...reveal the functional role exercised by immigrants, particularly in some central and northern areas of the country, for its economic growth...." The need to improve housing and make health services more accessible to migrants are discussed. The surveys were conducted during 1990 and 1991. (SUMMARY IN ENG AND FRE) excerpt

  8. Semiconductors and semimetals oxygen in silicon

    CERN Document Server

    Willardson, Robert K; Beer, Albert C; Shimura, Fumio

    1994-01-01

    This volume reviews the latest understanding of the behavior and roles of oxygen in silicon, which will carry the field into the ULSI era from the experimental and theoretical points of view. The fourteen chapters, written by recognized authorities representing industrial and academic institutions, cover thoroughly the oxygen related phenomena from the crystal growth to device fabrication processes, as well as indispensable diagnostic techniques for oxygen.Key Features* Comprehensive study of the behavior of oxygen in silicon* Discusses silicon crystals for VLSI and ULSI applications* Thorough coverage from crystal growth to device fabrication* Edited by technical experts in the field* Written by recognized authorities from industrial and academic institutions* Useful to graduate students, scientists in other disciplines, and active participants in the arena of silicon-based microelectronics research* 297 original line drawings

  9. Automotive Radar Sensors in Silicon Technologies

    CERN Document Server

    Jain, Vipul

    2013-01-01

    This book presents architectures and design techniques for mm-wave automotive radar transceivers. Several fully-integrated transceivers and receivers operating at 22-29 GHz and 77-81 GHz are demonstrated in both CMOS and SiGe BiCMOS technologies. Excellent performance is achieved indicating the suitability of silicon technologies for automotive radar sensors.  This book bridges an existing gap between information available on dependable system/architecture design and circuit design.  It provides the background of the field and detailed description of recent research and development of silicon-based radar sensors.  System-level requirements and circuit topologies for radar transceivers are described in detail. Holistic approaches towards designing radar sensors are validated with several examples of highly-integrated radar ICs in silicon technologies. Circuit techniques to design millimeter-wave circuits in silicon technologies are discussed in depth.  Describes concepts and fundamentals of automotive rada...

  10. A review on the “Modern and Contemporary Physics at High School” research area

    Directory of Open Access Journals (Sweden)

    Marco Antonio Moreira

    2000-01-01

    Full Text Available This paper presents a review of the literature regarding the subject “Modern and Contemporary Physics (MCP at secondary school level” based on research papers, textbooks, master’s and doctoral’s dissertations, curriculum projects, and internet papers, approaching this topic. This review focus on publications targeting the teaching of physics and includes the first studies in this line of research published in the late seventies. Six large categories of studies were identified. Among them, it was possible to identify a clear concentration of studies presenting MCP topics as popularization of science or as bibliographical reference for high school teachers. Just a few studies were found concerning students’ misconceptions about MCP topics as well as regarding classroom proposals with actual learning outcomes.

  11. On the development of the main research areas of the Arctic zone of the Russian Federation

    Directory of Open Access Journals (Sweden)

    Anatoly V. Shevchuk

    2016-04-01

    Full Text Available The article is focused on the current research trends in the field of environmental protection and security in the Arctic. This means the development of Arctic environmental safety strategies for the period untill 2030, pollution and the environmental situation in the Russian Arctic, use of strategic environmental assessment (SEA for the major infrastructure projects in terms of their impact on the Arctic environment and the possible damage, an environmental atlas of the Arctic zone of the Russian Federation within the project of the National Atlas of the Arctic. An assessment of the dumping impact (waste disposal in the sea on the environment of the Arctic and indigenous peoples, taking into account the transboundary transfer of pollutants. All the tasks of the environmental damage elimination could be solved by special programs. The authors also for-mulated the possible outcomes of the proposed research in the Arctic.

  12. Novel Gd-Loaded Silicon Nanohybrid: A Potential Epidermal Growth Factor Receptor Expressing Cancer Cell Targeting Magnetic Resonance Imaging Contrast Agent.

    Science.gov (United States)

    Sinha, Sougata; Tong, Wing Yin; Williamson, Nathan H; McInnes, Steven J P; Puttick, Simon; Cifuentes-Rius, Anna; Bhardwaj, Richa; Plush, Sally E; Voelcker, Nicolas H

    2017-12-13

    Continuing our research efforts in developing mesoporous silicon nanoparticle-based biomaterials for cancer therapy, we employed here porous silicon nanoparticles as a nanocarrier to deliver contrast agents to diseased cells. Nanoconfinement of small molecule Gd-chelates (L1-Gd) enhanced the T1 contrast dramatically compared to distinct Gd-chelate (L1-Gd) by virtue of its slow tumbling rate, increased number of bound water molecules, and their occupancy time. The newly synthesized Gd-chelate (L1-Gd) was covalently grafted on silicon nanostructures and conjugated to an antibody specific for epidermal growth factor receptor (EGFR) via a hydrazone linkage. The salient feature of this nanosized contrast agent is the capability of EGFR targeted delivery to cancer cells. Mesoporous silicon nanoparticles were chosen as the nanocarrier because of their high porosity, high surface area, and excellent biodegradability. This type of nanosized contrast agent also performs well in high magnetic fields.

  13. The research on regional conservation planning of urban historical and cultural areas based on GIS

    Science.gov (United States)

    Li, Shangli; Xu, Jian; Li, Qian

    2017-06-01

    With the rapid economic development and the growth of population happening in the urban historical and cultural areas, heritage and historical buildings along with their natural and artificial surrounding environments are suffering constructive destruction. Due to the lack of precise partition of protection region and construction control region in the local cultural relics protection law, traditional regional conservation planning cannot engaged with the urban controllability detailed planning very well. According to the several protection regulations about heritage and historical buildings from latest laws, we choose Baxian Temple area to study on the improvments of traditional regional conservation planning. The technical methods of this study mainly rely on GIS, which can complete the fundamental work of each stage. With the analytic hierarchy process(AHP), the comprehensive architectural value assessments can be calculated according to the investigation results. Based on the calculation results and visual corridor analysis, the precise range of protection region and construction control region can be decided and the specific protection measures can be formulated.

  14. Hydrocarbon origin and reservoir forming model research of Longwangmiao Formation, Moxi-Gaoshiti area, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Mindong Jin

    2016-06-01

    Full Text Available This paper focuses on the Longwangmiao gas reservoir in Moxi-Gaoshiti area, Sichuan Basin. Starting from the tectonic evolution perspective, though comparing biological marker compound and analyzing fluid inclusions, the oil & gas origin and accumulation evolution of Longwangmiao Formation are systematic studied with reference to the burial-thermal evolution of single well geological history in the study area. It is suggested that the oil & gas reservoir is generally characterized by early accumulation, multi-stage filling, late cracking and later adjustment. The oil and gas were mainly sourced from lower Cambrian Qiongzhusi Formation, partly from the Permian source rock. During the geological period, 3 major oil & gas fillings occurred in the Longwangmiao Formation, namely Caledonian-Hercynian filling that was small in scale and produced the first phase of paleo-oil reservoir that soon destroyed by Caledonian movement uplift, large-scale Permian filling that gave rise to the second-phase of paleo-oil reservoir and the Triassic-Jurassic filling that enriched the second phase of paleo-oil reservoir. Finally, the paleo-oil reservoir experienced an in-situ cracking during the cretaceous period that gave rise to a natural gas reservoir and left behind carbonaceous bitumen and oily bitumen in the holes of the Longwangmiao Formation.

  15. Management of communication area in a nuclear research and development institute

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Wellington Antonio [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil). Servico de Negocios e Comunicacao]. E-mail: soaresw@cdtn.br

    2005-07-01

    Nuclear energy to the general public is always associated to the production of nuclear weapons or to nuclear and radiological accidents. Public communication actions done by the National Commission of Nuclear Energy (CNEN) have been contributing to make known the social and peaceful applications of nuclear energy, reaching different kinds of public. Interaction programs with society and in particular with students have also been carried out by the Nuclear Technology Development Center (CDTN/CNEN). Measuring public communication results can help to show that financial resource in this area should be considered as investment and not as expenses. One needs therefore a well-established managing system. Fundamentals of the National Quality Award Criteria for Excellence - PNQ are being applied in the area in charge of business and public communication at CDTN. Systematic registration of results started in 2000 and a gradual increase in the number of means of communication for the internal public has occurred in the last five years. The Center has now a bimonthly newspaper edition. Communication indicators have shown an increasing number of students received in the Center or provided with lectures in schools. Results of satisfaction inquiry from these students show good results. The implemented management system has allowed informing the nature and quantity of people reached by the information on nuclear applications and the improvement in the institutional image. (author)

  16. Application Research on Drag Reduced Conductors for Electric Power Transmission Lines in Strong Wind Areas

    Directory of Open Access Journals (Sweden)

    Li Dong Qing

    2016-01-01

    Full Text Available The breeze vibration duration of conductors is long, the vibration amplitude is strong and the frequency range is wide for electric power transmission lines in strong wind areas, which seriously affects the safe and stable operation of transmission lines. There are two design schemes of conductors which can achieve the purpose of reducing wind-induced disaster. One is enhancing the structural strength of conductors to withstand wind load, but the investment is enormous and the effect is limited. The other is developing drag reduced conductors to reduce wind load by changing conductor structure. This paper started from application feasibility analysis of drag reduced conductors and designed four drag reduced conductors by structure optimization of the conventional aluminium conductor steel reinforced JL/G1A-630/45-45/7, denoted as DFY630/45(45°-R3.5, DFY630/45(60°-R3.5, DFY630/45(45°–R3.2 and DFY630/45(60°-R3.2, respectively. The wind tunnel test was performed and the wind resistance coefficients in unit length of five conductors were compared. Result showed that the wind resistance coefficients in unit length of four drag reduced conductors were obviously lower than that of the conventional conductor. By controlling the manufacturing process, popularization and application of drag reduced conductors for transmission lines in strong wind areas can be realized.

  17. NASA/ARMY/BELL XV-15 Tiltrotor Low-Noise Terminal Area Operations Flight Research Program

    Science.gov (United States)

    Edwards, Bryan D.; Conner, David A.; Decker, William A.; Marcolini, Michael A.; Klein, Peter D.

    2001-01-01

    To evaluate the noise reduction potential for tiltrotor aircraft, a series of three XV- 15 acoustic flight tests were conducted over a five-year period by a NASA/Army/Bell Helicopter team. Lower hemispherical noise characteristics for a wide range of steady-state terminal area type operating conditions were measured during the Phase I test and indicated that the takeoff and level flight conditions were not significant contributors to the total noise of tiltrotor operations. Phase I results were also used to design low-noise approach profiles that were tested later during the Phase 2 and Phase 3 tests. These latter phases used large area microphone arrays to directly measure ground noise footprints. Approach profiles emphasized noise reduction while maintaining handling qualities sufficient for tiltrotor commercial passenger ride comfort and flight safety under Instrument Flight Rules (IFR) conditions. This paper will discuss the weather, aircraft, tracking, guidance, and acoustic instrumentation systems, as well as the approach profile design philosophy, and the overall test program philosophy. Acoustic results are presented to document the variation in tiltrotor noise due to changes in operating condition, indicating the potential for significant noise reduction using the unique tiltrotor capability of nacelle tilt. Recommendations are made for a final XV-15 test to define the acoustic benefits of the automated approach capability which has recently been added to this testbed aircraft.

  18. History and photojournalism: reflections on the concept and research in the area

    OpenAIRE

    Charles Monteiro

    2016-01-01

    Abstract This article aims to think through historical research with press photography and photojournalism in the 1970-80s in Brazil by means of some reflection axes: the photographic image statute, the concept of photojournalism, the construction of a specific photojournalistic language on the pages of the media, the temporality of production and consumption of the various types of press photography, the forms of image circulation and reception.   Keywords: Photojournalism; Photo...

  19. Silicon Schottky Diode Safe Operating Area

    Science.gov (United States)

    Casey, Megan C.; Campola, Michael J.; Lauenstein, Jean-Marie; Wilcox, Edward P.; Phan, Anthony M.; LaBel, Kenneth A.

    2016-01-01

    Vulnerability of a variety of candidate spacecraft electronics to total ionizing dose and displacement damage is studied. Devices tested include optoelectronics, digital, analog, linear bipolar devices, and hybrid devices.

  20. Microplastics in the Antarctic marine system: An emerging area of research.

    Science.gov (United States)

    Waller, Catherine L; Griffiths, Huw J; Waluda, Claire M; Thorpe, Sally E; Loaiza, Iván; Moreno, Bernabé; Pacherres, Cesar O; Hughes, Kevin A

    2017-11-15

    It was thought that the Southern Ocean was relatively free of microplastic contamination; however, recent studies and citizen science projects in the Southern Ocean have reported microplastics in deep-sea sediments and surface waters. Here we reviewed available information on microplastics (including macroplastics as a source of microplastics) in the Southern Ocean. We estimated primary microplastic concentrations from personal care products and laundry, and identified potential sources and routes of transmission into the region. Estimates showed the levels of microplastic pollution released into the region from ships and scientific research stations were likely to be negligible at the scale of the Southern Ocean, but may be significant on a local scale. This was demonstrated by the detection of the first microplastics in shallow benthic sediments close to a number of research stations on King George Island. Furthermore, our predictions of primary microplastic concentrations from local sources were five orders of magnitude lower than levels reported in published sampling surveys (assuming an even dispersal at the ocean surface). Sea surface transfer from lower latitudes may contribute, at an as yet unknown level, to Southern Ocean plastic concentrations. Acknowledging the lack of data describing microplastic origins, concentrations, distribution and impacts in the Southern Ocean, we highlight the urgent need for research, and call for routine, standardised monitoring in the Antarctic marine system. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Based on Wide Area Environment Abnormal Behavior Analysis and Anomaly Detection Research

    Directory of Open Access Journals (Sweden)

    Zhang Lin

    2016-01-01

    Full Text Available Group anomaly identification and location is an important issue in the field of artificial intelligence. Capture of the accident source and rapid prediction of mass incidents in public places are difficult problems in intelligent video identification and processing, but the traditional group anomaly detection research has many limitations when it comes to accident source detection and intelligent recognition. We are to research on the algorithms of accident source location and abnormal group identification based on behavior analysis in the condition of dramatically changing group geometry appearance, including: 1 to propose a logic model of image density based on the social force model, and to build the crowd density trend prediction model integrating “fast and fuzzy matching at front-end” and “accurate and classified training at back-end”; 2 to design a fast abnormal source flagging algorithm based on support vector machine, and to realize intelligent and automatic marking of abnormal source point; 3 to construct a multi-view human body skeleton invariant moment model and a motion trajectory model based on linear parametric equations. The expected results of the research will help prevent abnormal events effectively, capture the first scene of incidents and the abnormal source point quickly, and play a decision support role in the proactive national security strategy.

  2. Hybrid III-V/silicon lasers

    Science.gov (United States)

    Kaspar, P.; Jany, C.; Le Liepvre, A.; Accard, A.; Lamponi, M.; Make, D.; Levaufre, G.; Girard, N.; Lelarge, F.; Shen, A.; Charbonnier, P.; Mallecot, F.; Duan, G.-H.; Gentner, J.-.; Fedeli, J.-M.; Olivier, S.; Descos, A.; Ben Bakir, B.; Messaoudene, S.; Bordel, D.; Malhouitre, S.; Kopp, C.; Menezo, S.

    2014-05-01

    The lack of potent integrated light emitters is one of the bottlenecks that have so far hindered the silicon photonics platform from revolutionizing the communication market. Photonic circuits with integrated light sources have the potential to address a wide range of applications from short-distance data communication to long-haul optical transmission. Notably, the integration of lasers would allow saving large assembly costs and reduce the footprint of optoelectronic products by combining photonic and microelectronic functionalities on a single chip. Since silicon and germanium-based sources are still in their infancy, hybrid approaches using III-V semiconductor materials are currently pursued by several research laboratories in academia as well as in industry. In this paper we review recent developments of hybrid III-V/silicon lasers and discuss the advantages and drawbacks of several integration schemes. The integration approach followed in our laboratory makes use of wafer-bonded III-V material on structured silicon-on-insulator substrates and is based on adiabatic mode transfers between silicon and III-V waveguides. We will highlight some of the most interesting results from devices such as wavelength-tunable lasers and AWG lasers. The good performance demonstrates that an efficient mode transfer can be achieved between III-V and silicon waveguides and encourages further research efforts in this direction.

  3. Drug delivery via porous silicon: a focused patent review.

    Science.gov (United States)

    Kulyavtsev, Paulina A; Spencer, Roxanne P

    2017-03-01

    Although silicon is more commonly associated with computer chips than with drug delivery, with the discovery that porous silicon is a viable biocompatible material, mesoporous silicon with pores between 2 and 50 nm has been loaded with small molecule and biomolecule therapeutics and safely implanted for controlled release. As porous silicon is readily oxidized, porous silica must also be considered for drug delivery applications. Since 2010, only a limited number of US patents have been granted, primarily for ophthalmologic and immunotherapy applications, in contrast to the growing body of technical literature in this area.

  4. Advanced Research on the Electrode Area of a Low Pressure Hg-Ar Discharge Lamp

    Science.gov (United States)

    Shi, Jianou

    The phenomenon of electrical discharge in low pressure Hg-Ar vapor has been under continuous investigation since it was first discovered. Because much work has been done in the positive column, it is, therefore, that the electrode area of the lamp is the main focus of this thesis. To simulate the interface phenomena on a electrode surface, samples, with optically smooth tungsten-barium interfaces were fired in a high vacuum furnace at different temperatures. Measurements were made using surface characterization techniques. It is found that no Ba_3WO _6 is formed on the surface as previously reported in the powder mixing experiments, and the interface consists mainly of BaWO_4. It was discovered in the early 1950's that vaporization of the barium from the cathode in a fluorescent lamp could be reduced tremendously with the addition of 5% of ZrO _2 to the coating mix. However, the reason for this is poorly understood. A possible explanation has been found, and number of tests have been completed to simulate the formation of BaZO_3 under different lamp operating conditions. The measurements and simulation of barium atom and ion number densities are presented. Barium emitted from the electrode surface has a strong interaction with the local plasma. The number density distributions depend mainly on the discharge conditions. A Monte Carlo computer simulation for the barium ion number density is described and the results from the simulation compared to the experimental results obtained by absorption method. It is clear that the ion distribution and phosphor contamination in the electrode area are two closely related issues. XPS is used to measure the chemical composition on the phosphor surface of the lamp. A discussion of calibration methods and the possible compounds forming on the phosphors is then presented. A number of questions have been raised concerning the safety of the lamp and its affects on health related to radiation generated in the electrode area. Typically

  5. Silicon strip detector qualification for the CMS experiment

    CERN Document Server

    Kaußen, Gordon

    2008-01-01

    The Compact Muon Solenoid (CMS) is one of the four experiments being installed at the Large Hadron Collider (LHC) which is located at the european organization for nuclear research CERN in Geneva. This proton-proton collider will explore a new energy regime of up to 14TeV center-of-mass energy. To provide the best spatial resolution for the particle trajectory reconstruction and a very fast readout, the inner tracking system of CMS is build up of silicon detectors with a pixel tracker in the center surrounded by a strip tracker. The silicon strip tracker consists of so-called modules representing the smallest detection unit of the tracking device. These modules are mounted on higher-level structures called shells in the tracker inner barrel (TIB), rods in the tracker outer barrel (TOB), disks in the tracker inner disks (TID) and petals in the tracker end caps (TEC). The entire strip tracker spans an active area of about 198m2 and consists of approximately 16000 modules. Before the silicon sensors were assembl...

  6. Research on large area VUV-sensitive gaseous photomultipliers for cryogenic applications

    Science.gov (United States)

    Coimbra, Artur Emanuel Cardoso

    Desde cedo que a comunidade cientifica compreendeu que gases nobres em liquido sao excelentes meios de deteccao de radiacao, combinando a sua elevada densidade, elevado grau de homogeneidade e de elevado rendimento de cintilacao. Para alem destas caracteristicas inerentes, estes tem a potencialidade de fornecer ambos sinais de ionizacao - criando electroes livres - e cintilacao em resposta a interaccao com radiacao ionizante e, tendo em vista a sua aplicacao em experiencias de eventos raros relacionados com fisica de neutrinos ou materia-escura, a capacidade de autoblindagem garante a exclusao de eventos induzidos por radiacao de fundo. O facto de nao absorverem a sua propria luz, emergente dos eventos de cintilacao, permite a expansao deste tipo de detectores ate grandes volumes, sendo que as colaboracoes mais recentes propoem detectores com dezenas de toneladas de xenon em estado liquido. As experiencias actuais que usam gases nobres em estado liquido empregam xenon ou argon numa so fase (estado liquido) ou em dupla-fase (estado liquido + gasoso) e as suas aplicacoes abrangem desde as ja referidas experiencias de procura de eventos raros, passando por imagiologia medica tais como detectores de radiacao gama para PET ou câmaras Compton "3-gamma" em combinacao com PET, passando tambem por aplicacoes de seguranca como sistemas de inspeccao para deteccao de material fissil e, finalmente, em câmaras Compton para aplicacoes de astrofisica. Em ambas as configuracoes a leitura dos sinais de cintilacao e geralmente feita atraves de um grande numero de dispendiosos fotomultiplicadores de vacuo agrupados. A presente tese de doutoramento e dedicada aos fotomultiplicadores gasosos de grande area para aplicacoes criogenicas desenvolvidos no contexto do programa doutoral, tendo em vista a sua eventual aplicacao como um dispositivo complementar aos metodos existentes de deteccao de cintilacao, para aplicacao em futuras experiencias de grande escala. Esta pesquisa foi

  7. Southwest Research Institute assistance to NASA in biomedical areas of the technology

    Science.gov (United States)

    Culclasure, D. F.; Eckhardt, L.

    1971-01-01

    Significant applications of aerospace technology were achieved. These applications include: a miniaturized, noninvasive system to telemeter electrocardiographic signals of heart transplant patients during their recuperative period as graded situations are introduced; and economical vital signs monitor for use in nursing homes and rehabilitation hospitals to indicate the onset of respiratory arrest; an implantable telemetry system to indicate the onset of the rejection phenomenon in animals undergoing cardiac transplants; an exceptionally accurate current proportional temperature controller for pollution studies; an automatic, atraumatic blood pressure measurement device; materials for protecting burned areas in contact with joint bender splints; a detector to signal the passage of animals by a given point during ecology studies; and special cushioning for use with below-knee amputees to protect the integrity of the skin at the stump/prosthesis interface.

  8. A Mechanochemical Approach to Porous Silicon Nanoparticles Fabrication

    Directory of Open Access Journals (Sweden)

    Luca De Stefano

    2011-06-01

    Full Text Available Porous silicon samples have been reduced in nanometric particles by a well known industrial mechanical process, the ball grinding in a planetary mill; the process has been extended to crystalline silicon for comparison purposes. The silicon nanoparticles have been studied by X-ray diffraction, infrared spectroscopy, gas porosimetry and transmission electron microscopy. We have estimated crystallites size from about 50 nm for silicon to 12 nm for porous silicon. The specific surface area of the powders analyzed ranges between 100 m2/g to 29 m2/g depending on the milling time, ranging from 1 to 20 h. Electron microscopy confirms the nanometric size of the particles and reveals a porous structure in the powders obtained by porous silicon samples which has been preserved by the fabrication conditions. Chemical functionalization during the milling process by a siloxane compound has also been demonstrated.

  9. Summary of the research methods of DNAPL-water interfacial area and DNAPL saturation in porous media

    Science.gov (United States)

    Li, M.; Wan, L.

    2016-12-01

    The dense non-aqueous phase liquid (DNAPL)-water interfacial area and DNAPL saturation are key factors in groundwater pollution remediation. The research methods of DNAPL-water interfacial area were summarized, including interfacial partitioning tracer tests, synchrotron X-ray microtomography and theoretical models, and the disparity of the study results with different methods was analyzed. The applications of DNAPL saturation measurement methods including tracer test method, light transmission visualization (LTV) and electrical resistivity tomography (ERT) were also summarized, especially the current applications of light transmission method in China. The partitioning tracer test, as an important method in the study of correlation between DNAPL-water interfacial areas and DNAPL saturation for porous media systems, should be given more attention in laboratory and field experiments.

  10. Results of research in the area of nanotechnologies and nanomaterials. Part 3

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2014-06-01

    Full Text Available To popularize scientific achievements in construction the main results of Russian and foreign scientists’ research are published in the form of abstract. The research «Stability of magnetic states of metal nanosystems» has developed multivariable theory of transition state for magnetic systems. The expression for the coefficient of magnetic transition rate in systems with arbitrary degrees of freedom was obtained. The algorithms to find the way with the minimal energy gap in multidimensional configuration space, localization of saddle points in multidimensional energy zone and to calculate magnetic states life spans have been developed. According to non-collinear generalization of Aleksander-Andersen model «magnetic theorem on forces» was proved. Using this theorem analytical expressions for energy gradient at arbitrary point of configuration space were deduced, that provided qualitative decrease of self-matched computation time. In the research «Rectification of nano- and microparticles in rotating spiral frames when analyzing polydispersed samples» method of flowing rectification of particles in transverse field of centrifugal forces, in planetary centrifuges equipped with rotating frames (RF was developed. The application of the method was broaden: the opportunity to divide submicroscopic particles by changing geometry of frame drum without increasing rotation speed was demonstrated. The use of cylindric RF with symmetrical flange made it possible to increase efficiency of rectification and extract practically monodisperse fractions of particles from their mixture. For the first time flowing rectification in transverse magnetic field was used to extract weight fractions of the particles which sizes are 50–300 nm, 300–1000 nm, 1–10 μm and 10–100 μm from dust samples for further analysis.

  11. Results of research in the area of nanotechnologies and nanomaterials. Part 5.

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2014-10-01

    Full Text Available To popularize scientific achievements in construction the main results of Russian and foreign scientists’ research are published in the form of abstract. These are main results of the research «Polymer construction nanocomposites based on polyvinylchloride»: technological recommendations on the use of multilayer carbon nanotubes, silicagel functionalized with the sulfur and silica sol in receipts of shape-moulded PVC-products for construction industry which allow increasing strength by 12–25%, thermal stability by 35–50% and decreasing melt viscosity (the factor increases 2–5 times; receipts and technology for production of high-filled construction composites based on PVC functionalized with silica sol and wood flour with population up to 68 mass.% when molding index is increased 12 times and thermal stability is increased by 60%. The specialists may be interested in the results of the following research: – I.S. Maeva «Modification of anhydride compositions with ultra- and nanodispersed additives»; – E.G. Chebotareva «Nanomodified composites of construction purpose with the use of epoxy resin»; – A.A. Volodchenko «Non-autoclave silicate materials with the use of natural nanodispersed raw materials»; – O.V. Popkova «Production and properties of metal-containing nanoparticles (Fe, Co, Ni, Zn, Ce, Cd, Pd, Ag, Mo, stabilized by nanodiamond of denotational synthesis and high pressure polyethylene»; – M.A. Fronya «Complex study of mechanical properties and structure of polymer composite materials with carbon modification fillers: nanotubes and ultradispersed diamonds»; – M.S. Babaeva «Production and study of nanoparticles of polymer-colloid complexes based on polymers of N,N-diallyl-N,N-chloride dimethylammonium and natrium dodecylsulfate». Published materials can be used by the specialists in their scientific and practical activities in construction, housing and communal services as well as in the joint economical

  12. JPRS Report, Science & Technology, Japan: Status, Development Direction of Advanced Multidisciplinary Research Areas

    Science.gov (United States)

    1992-02-20

    Morishita, Y. Tamura and T. Otsuki, 1990 IEEE Inter- national Solid-State Circuit Conference, paper no TPM 9.2, 1990. 8. M. Holler, S. Tam, H. Castro and R...djoponlos 13 Mutagen susceptibility UK H.I. Evans of human cells 14 Radiation susceptibil- UK D. Scott ity of human cells 15 Mechanisms of chromo...Holland A.T. some abnormality Natarajan formation 16 Environmental mutagens several F.H. coun- Sobels tries 152 Table 2.5.2-2 Summary of Foreign Researchers

  13. History and photojournalism: reflections on the concept and research in the area

    Directory of Open Access Journals (Sweden)

    Charles Monteiro

    2016-08-01

    Full Text Available Abstract This article aims to think through historical research with press photography and photojournalism in the 1970-80s in Brazil by means of some reflection axes: the photographic image statute, the concept of photojournalism, the construction of a specific photojournalistic language on the pages of the media, the temporality of production and consumption of the various types of press photography, the forms of image circulation and reception.   Keywords: Photojournalism; Photography; History and press.   Original title: História e Fotojornalismo: reflexões sobre o conceito e a pesquisa na área.

  14. Modular fabrication and characterization of complex silicon carbide composite structures Advanced Reactor Technologies (ART) Research Final Report (Feb 2015 – May 2017)

    Energy Technology Data Exchange (ETDEWEB)

    Khalifa, Hesham [General Atomics, San Diego, CA (United States)

    2017-08-03

    Advanced ceramic materials exhibit properties that enable safety and fuel cycle efficiency improvements in advanced nuclear reactors. In order to fully exploit these desirable properties, new processing techniques are required to produce the complex geometries inherent to nuclear fuel assemblies and support structures. Through this project, the state of complex SiC-SiC composite fabrication for nuclear components has advanced significantly. New methods to produce complex SiC-SiC composite structures have been demonstrated in the form factors needed for in-core structural components in advanced high temperature nuclear reactors. Advanced characterization techniques have been employed to demonstrate that these complex SiC-SiC composite structures provide the strength, toughness and hermeticity required for service in harsh reactor conditions. The complex structures produced in this project represent a significant step forward in leveraging the excellent high temperature strength, resistance to neutron induced damage, and low neutron cross section of silicon carbide in nuclear applications.

  15. [Eating behavior and life styles: research and action on nutrition in a rural area].

    Science.gov (United States)

    Grand-Filaire, A; Monnier, E; Grand, A; Pous, J; Douste-Blazy, P; Palustran, N

    1986-12-01

    Nutrition education has sometimes been portrayed as a normative discourse, forgetting that nutrition is at the heart of basic lifestyle habits. In fact, eating not only satisfies a basic need, it is a social and communication action that develops an interaction with a person's socio-economic and cultural framework. This article describes an educational programme that involved all 2,200 inhabitants of a small rural town in the south of France. The purpose of the study was to better define what was involved in the development of eating behaviours in order to adapt information for the population. Two hundred families, 28% of the town, were provided with a survey questionnaire. Questions about socio-economic and cultural data of the families, types of food provisions, cooking initiation, perceived knowledge of dietetics, and ways of sociability were included. This research permitted the identification of different profiles of eaters: working class families, the elderly, families without children, etc... The subsequent information campaign attempted to adapt its message to each category identified, taking into consideration economic and psychosocial factors, the attachment of the population to its culinary patrimony, and the pejorative vision of dietetics perceived by part of the population. The entire community collaborated at each stage of the programme. Conceived as a research project, it contributed to motivating the population to take an active role in the management of its health problems.

  16. Drosophotoxicology: An Emerging Research Area for Assessing Nanoparticles Interaction with Living Organisms

    Directory of Open Access Journals (Sweden)

    Mariana Carmen Chifiriuc

    2016-02-01

    Full Text Available The rapid development of nanotechnology allowed the fabrication of a wide range of different nanomaterials, raising many questions about their safety and potential risks for the human health and environment. Most of the current nanotoxicology research is not standardized, hampering any comparison or reproducibility of the obtained results. Drosophotoxicology encompasses the plethora of methodological approaches addressing the use of Drosophila melanogaster as a choice organism in toxicology studies. Drosophila melanogaster model offers several important advantages, such as a relatively simple genome structure, short lifespan, low maintenance cost, readiness of experimental manipulation comparative to vertebrate models from both ethical and technical points of view, relevant gene homology with higher organisms, and ease of obtaining mutant phenotypes. The molecular pathways, as well as multiple behavioral and developmental parameters, can be evaluated using this model in lower, medium or high throughput type assays, allowing a systematic classification of the toxicity levels of different nanomaterials. The purpose of this paper is to review the current research on the applications of Drosophila melanogaster model for the in vivo assessment of nanoparticles toxicity and to reveal the huge potential of this model system to provide results that could enable a proper selection of different nanostructures for a certain biomedical application.

  17. A targeted review of the neurobiology and genetics of behavioural addictions: an emerging area of research.

    Science.gov (United States)

    Leeman, Robert F; Potenza, Marc N

    2013-05-01

    This review summarizes neurobiological and genetic findings in behavioural addictions, draws parallels with findings pertaining to substance use disorders, and offers suggestions for future research. Articles concerning brain function, neurotransmitter activity, and family history and (or) genetic findings for behavioural addictions involving gambling, Internet use, video game playing, shopping, kleptomania, and sexual activity were reviewed. Behavioural addictions involve dysfunction in several brain regions, particularly the frontal cortex and striatum. Findings from imaging studies incorporating cognitive tasks have arguably been more consistent than cue-induction studies. Early results suggest white and grey matter differences. Neurochemical findings suggest roles for dopaminergic and serotonergic systems, but results from clinical trials seem more equivocal. While limited, family history and genetic data support heritability for pathological gambling and that people with behavioural addictions are more likely to have a close family member with some form of psychopathology. Parallels exist between neurobiological and genetic and family history findings in substance and nonsubstance addictions, suggesting that compulsive engagement in these behaviours may constitute addictions. To date, findings are limited, particularly for shopping, kleptomania, and sexual behaviour. Genetic understandings are at an early stage. Future research directions are offered.

  18. A Targeted Review of the Neurobiology and Genetics of Behavioral Addictions: An Emerging Area of Research

    Science.gov (United States)

    Leeman, Robert F.; Potenza, Marc N.

    2013-01-01

    This review summarizes neurobiological and genetic findings in behavioral addictions, draws parallels with findings pertaining to substance use disorders and offers suggestions for future research. Articles concerning brain function, neurotransmitter activity and family history/genetics findings for behavioral addictions involving gambling, internet use, video game playing, shopping, kleptomania and sexual activity were reviewed. Behavioral addictions involve dysfunction in several brain regions, particularly the frontal cortex and striatum. Findings from imaging studies incorporating cognitive tasks have arguably been more consistent than cue-induction studies. Early results suggest white and gray matter differences. Neurochemical findings suggest roles for dopaminergic and serotonergic systems, but results from clinical trials seem more equivocal. While limited, family history/genetic data support heritability for pathological gambling and that those with behavioral addictions are more likely to have a close family member with some form of psychopathology. Parallels exist between neurobiological and genetic/family history findings in substance and non-substance addictions, suggesting that compulsive engagement in these behaviors may constitute addictions. Findings to date are limited, particularly for shopping, kleptomania and sexual behavior. Genetic understandings are at an early stage. Future research directions are offered. PMID:23756286

  19. Modeling Indirect Tunneling in Silicon

    Science.gov (United States)

    Chen, Edward

    Indirect tunneling in silicon p-n junctions catches people's attention again in recent years. First, the phenomenon induces a serious leakage problem, so called gate-induced drain leakage (GIDL) effect, in modern metal-oxide-semiconductor field-effect transistors (MOSFETs). Second, it is utilized to develop a novel tunneling transistor with the sharp turn-on ability for continuing ITRS roadmap. Although the indirect tunneling is important for the state-of-the-art transistor-technology, the accuracy of the present tunneling models in technology computer-aided design (TCAD) tools is still vague. In the research work, the theory of indirect tunneling in silicon has been thoroughly studied. The phonon-assisted tunneling model has been developed and compared with the existing ones in the Sentaurus-Synopsys, Medici-Synopsys, and Atlas-Silvaco TCAD tools. Beyond these existing models, ours successfully predicts the indirect tunneling current under the different field direction in silicon. In addition, bandgap narrowing in heavily-doped p-n junctions under the reverse-biased condition is also studied during the model development. At the end of the research work, the application to low standby power (LSTP) transistors is demonstrated to show the capability of our tunneling model in the device level.

  20. Photonic Crystal Sensors Based on Porous Silicon

    Directory of Open Access Journals (Sweden)

    Claudia Pacholski

    2013-04-01

    Full Text Available Porous silicon has been established as an excellent sensing platform for the optical detection of hazardous chemicals and biomolecular interactions such as DNA hybridization, antigen/antibody binding, and enzymatic reactions. Its porous nature provides a high surface area within a small volume, which can be easily controlled by changing the pore sizes. As the porosity and consequently the refractive index of an etched porous silicon layer depends on the electrochemial etching conditions photonic crystals composed of multilayered porous silicon films with well-resolved and narrow optical reflectivity features can easily be obtained. The prominent optical response of the photonic crystal decreases the detection limit and therefore increases the sensitivity of porous silicon sensors in comparison to sensors utilizing Fabry-Pérot based optical transduction. Development of porous silicon photonic crystal sensors which allow for the detection of analytes by the naked eye using a simple color change or the fabrication of stacked porous silicon photonic crystals showing two distinct optical features which can be utilized for the discrimination of analytes emphasize its high application potential.

  1. Presentation of the results of 1993-1994 of the peat production research area; Turvetuotanto - tutkimusalueen katsaus

    Energy Technology Data Exchange (ETDEWEB)

    Leinonen, A.

    1996-12-31

    The development target of the peat production research area of the Biomass research programme is to improve the competitivity of peat by reducing the production costs by 20 % (5-6 FIM/MWh) from the level of 1992 and to reduce the environmental load. The main targets of peat production, by which the target can be met, are ditching and preparation technologies, drying technology, machine technology, methodology, integration of wood harvesting and peat production, and application of the results of the Optimiturve research programme in practice. The objectives of the peat production research are possible to meet if the partial targets are met. Increment of the open-ditch distance from 20 m to 60 m reduces the production costs by 5.0 %, increment of the rate of utilization of solar radiation from 30 % to 40 % reduces the production costs by 8 %, reduction of the amount of residual peat from 3000 MWh to 1500 MWh reduces the costs by 6.5 %, development of light and firesafe machines by 3 %, and integrated harvesting of wood by 3 %. Meeting of the partial targets reduces the production costs by 24 %. The main research areas of peat production will be carried out further. The total funding of the peat production researches in 1993-1994 was 19.4 million FIM (9.7 million FIM/a). The share of the total funding of the research organization projects has been 6.7 million FIM and that of the company projects 12.7 million FIM. The share of the Finnish Ministry of Trade and Industry of the funding has been 9.0 million FIM (46 %)

  2. The Hawai'i Undersea Research Laboratory: Applying Innovative Deep-sea Technologies Toward Research, Service, and Stewardship in Marine Protected Areas of the Pacific Region

    Science.gov (United States)

    Smith, J. R.

    2012-12-01

    The Hawai'i Undersea Research Laboratory (HURL) is the only U.S. deep submergence facility in the Pacific Rim tasked with supporting undersea research necessary to fulfill the mission, goals, and objectives of the National Oceanic and Atmospheric Administration (NOAA), along with other national interests of importance. Over 30 years of submersible operations have resulted in nearly 1900 dives representing 9300 hours underwater, and a benthic ecology database derived from in-house video record logging of over 125,000 entries based on 1100 unique deep-sea animal identifications in the Hawaiian Archipelago. As a Regional Center within the Office of Ocean Exploration and Research (OER), HURL conducts undersea research in offshore and nearshore waters of the main and Northwestern Hawaiian Islands and waters of the central, southern, and western Pacific. HURL facilities primarily support marine research projects that require data acquisition at depths greater than wet diving methods. These consist of the research vessel Ka'imikai-o-Kanaloa (KOK), human occupied submersibles Pisces IV and Pisces V (2000 m), a new remotely operated vehicle (6000 m), and a multibeam bathymetric sonar system (11,000 m). In addition, HURL has also supported AAUS compliant wet diving since 2003, including technical mixed gas/rebreather work. While ecosystem studies of island, atoll, and seamount flanks are the largest component of the HURL science program, many other thematic research areas have been targeted including extreme and unique environments, new resources from the sea, episodic events to long term changes, and the development of innovative technologies. Several examples of HURL's contributions to marine protected areas (MPAs) include: (a) A long term presence in the pristine ecosystems of the Papahānaumokuākea Marine National Monument in the Northwestern Hawaiian Islands. Researchers from National Marine Fisheries have used HURL assets to study endangered Hawaiian Monk Seal habitat

  3. Conductive heat flows in research drill holes in thermal areas of Yellowstone National Park, Wyoming

    Science.gov (United States)

    White, Donald E.

    1978-01-01

    In convection systems with boiling springs, geysers, fumaroles, and other thermal features, the modes of heat flow become increasingly complex as a single liquid phase at depth rises into the near-surface environment where heat flows by convection of liquid and vapor and by conduction in high thermal gradients. This paper is mainly concerned with the changing patterns of conductive heat flow as related to channels of subsurface convective flow and to horizontal distance from spring vents. The primary data consist of temperatures measured in 13 cored drill holes as drilling progressed. Some temperatures plot convincingly on straight-line segments that suggest conductive gradients in rocks of nearly constant thermal conductivity. Temperature gradients and the conductive component of total heat flow nearly always decrease drastically downward; the gradient and heat flow of the lowest depth interval recognized in each hole is commonly only about 10 percent of the highest interval; the changes in gradient at interval boundaries are commonly interpreted as channels of near-boiling water or of cooler meteoric water. Temperature reversals are probably related to inflowing cooler water rather than to transient effects from recent changes. Some temperatures plot on curved segments that probably indicate dispersed convective upflow and boiling of water in ground penetrated by the drill hole. Other similar curved segments are too low in temperature for local boiling and are probably on the margins of hot upflow zones, reflecting conductive cooling of flowing water. The conifers of Yellowstone National Park (mainly lodgepole pine) seem to have normal growth characteristics where near-surface conductive heat flow is below about 200 heat-flow units (1 HFU = 10-6 cal/cm2 = 41.8 mW/m2). Most areas of abnormal "stunted" trees (low ratio of height to base diameter, and low density of spacing) are characterized by conductive heat flows of about 250 to 350 HFU. The critical factor

  4. Silicon nanowire properties from theory and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Scheel, H.M.

    2007-09-10

    Silicon has played an outstanding role at the end of the 20th century and is still one of the most important components for micro computing. In recent years the ability to miniaturize semiconductor structures and devices to nanometer length scales has opened an all new field of physics, i.e. nanoscience. Simply by miniaturizing the size of semiconducting structures the physics describing electronic or vibronic properties has to be altered fundamentally leading to new phenomena and interesting effects. For silicon the two major mile-stones where the fabrication of porous silicon and later the fabrication of free-standing silicon nanowires. The intense research concerning the fabrication of silicon nanowires has led to single crystalline nanowires with diameters of only a few nanometers. The hope that drove these intense research efforts where to find efficient photonic properties in these quantized systems. In the first part of this work detailed theoretical investigations are presented for the commonly observed ([111] and [11 anti 2]) representatives of free-standing and for the most frequently discussed ([001]) silicon nanowires not (so far) observed as free standing wires. Using density functional theory in the local density approximation the electronic properties as well as the structural changes due to the reduced dimensionality of silicon nanowires are calculated and discussed. The comparison to recent experimental, scanning tunneling experiments reveal a fundamental discrepancy between the calculated band structures and experimental findings. With our results we are able to explain these differences. Raman investigations on silicon nanowires where in a state of controversial discussion about the origin of observed red shifted spectra. Various contributions like quantum confinement, photo excitation and thermal effects where discussed. The second part of this thesis contributes to this discussion, with detailed laser power dependent Raman spectroscopic

  5. Nonlinear silicon photonics

    Science.gov (United States)

    Borghi, M.; Castellan, C.; Signorini, S.; Trenti, A.; Pavesi, L.

    2017-09-01

    Silicon photonics is a technology based on fabricating integrated optical circuits by using the same paradigms as the dominant electronics industry. After twenty years of fervid development, silicon photonics is entering the market with low cost, high performance and mass-manufacturable optical devices. Until now, most silicon photonic devices have been based on linear optical effects, despite the many phenomenologies associated with nonlinear optics in both bulk materials and integrated waveguides. Silicon and silicon-based materials have strong optical nonlinearities which are enhanced in integrated devices by the small cross-section of the high-index contrast silicon waveguides or photonic crystals. Here the photons are made to strongly interact with the medium where they propagate. This is the central argument of nonlinear silicon photonics. It is the aim of this review to describe the state-of-the-art in the field. Starting from the basic nonlinearities in a silicon waveguide or in optical resonator geometries, many phenomena and applications are described—including frequency generation, frequency conversion, frequency-comb generation, supercontinuum generation, soliton formation, temporal imaging and time lensing, Raman lasing, and comb spectroscopy. Emerging quantum photonics applications, such as entangled photon sources, heralded single-photon sources and integrated quantum photonic circuits are also addressed at the end of this review.

  6. ALICE silicon strip module

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    This small silicon detector strip will be inserted into the inner tracking system (ITS) on the ALICE detector at CERN. This detector relies on state-of-the-art particle tracking techniques. These double-sided silicon strip modules have been designed to be as lightweight and delicate as possible as the ITS will eventually contain five square metres of these devices.

  7. Silicon Valley: Planet Startup

    NARCIS (Netherlands)

    Dr. P. Ester; dr. A. Maas

    2016-01-01

    For decades now, Silicon Valley has been the home of the future. It's the birthplace of the world's most successful high-tech companies-including Apple, Yahoo, Google, Facebook, Twitter, and many more. So what's the secret? What is it about Silicon Valley that fosters entrepreneurship and

  8. 77 FR 63788 - Crystalline Silicon Photovoltaic Cells, Whether or Not Assembled Into Modules, From the People's...

    Science.gov (United States)

    2012-10-17

    ... crystalline silicon photovoltaic cells, not exceeding 10,000 mm\\2\\ in surface area, that are permanently... International Trade Administration Crystalline Silicon Photovoltaic Cells, Whether or Not Assembled Into Modules... countervailable subsidies are being provided to producers and exporters of crystalline silicon photovoltaic cells...

  9. Results of research in the area of nanotechnologies and nanomaterials. Part 6

    Directory of Open Access Journals (Sweden)

    KARPOV Alexey Ivanovich

    2014-12-01

    Full Text Available To popularize scientific achievements in construction the main results of Russian and foreign scientists’ research are published in the form of abstract. The result of research «Cement composites with additives of multi-layer carbon nanotubes (MLCN» is a new production technology and optimal compositions for complex nanomodified additives (CNMA. Introduction of such additives in the quantity of 12 mass.% of cement mass provides within 8–12 hours early stripping strength more than 15–40 Mpa, water impermeability more than W20 and frost resistance F60–F700. The technology provides double increase of work performance and metalriging turnover. The difference between the new production technology and the traditional one is that the line of production of chemical additives contains a new unit designed for manufacture of CNMA based on MLCN. The unit consists of precision feeder (the size of dose is 5 g., ultrasound dispersant with power 4 kW and frequency of operation 22 kHz and turbulent mixer with power 7,5 kW. The developed technology provides precise dose and even distribution of CNMA in mixture. The author developed technical conditions № 5745-111-02069622-2013 for manufacture of CNMA based on MLCN of different refinement purity and dispersiveness for high strength reinforced-concrete blocks used as finishing materials in subway tunnels. The specialists may be also interested in results of the research «Nanostructured perlite binder and foam concrete based on it» by Miroshnikov E.V., «Constructional steel fiber concretes modified with complex carbon micro- and nanosize additives» by Alatorceva U.V., «Physical and chemical study of nanocomposite template-assembled materials produced with the controlled sol-gel synthesis» by Krekoten' A.V., «Production and study of nanoparticles of polymer-colloid complexes based on polymers of chloride N,N-diallyl-N,N-dimethylammonio and dodecylsulfate sodium» by Babaeva M.S.,

  10. Silicon Sheet Growth Development for the Large Area Sheet Task of the Low Cost Solar Array Project. Heat Exchanger Method - Ingot Casting Fixed Abrasive Method - Multi-Wire Slicing

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1978-01-01

    Solar cells fabricated from HEM cast silicon yielded up to 15% conversion efficiencies. This was achieved in spite of using unpurified graphite parts in the HEM furnace and without optimization of material or cell processing parameters. Molybdenum retainers prevented SiC formation and reduced carbon content by 50%. The oxygen content of vacuum cast HEM silicon is lower than typical Czochralski grown silicon. Impregnation of 45 micrometers diamonds into 7.5 micrometers copper sheath showed distortion of the copper layer. However, 12.5 micrometers and 15 micrometers copper sheath can be impregnated with 45 micrometers diamonds to a high concentration. Electroless nickel plating of wires impregnated only in the cutting edge showed nickel concentration around the diamonds. This has the possibility of reducing kerf. The high speed slicer fabricated can achieve higher speed and longer stroke with vibration isolation.

  11. The application of market research in contraceptive social mass marketing in a rural area of Kenya.

    Science.gov (United States)

    Black, T R; Farley, J U

    1979-01-01

    Because of the restricted nature of clinic systems, commercial channels and social marketing techniques are now being mobilized for family planning purposes. Market research is fundamental to the success of such programs. In addition to normal survey procedures and the limitations of analysis merely in terms of pairwise relationships, systems models are applied to the survey findings of a Kenya contraceptive social marketing experiment in order to gain insights into the enogenous and exogenous variables relating to consumer behavior using bivariate techniques. The results of such analysis on the survey findings are presented. The conclusion is drawn that model building methodologies as described for evaluating contraceptive social marketing programs do not present any significant difficulties and that it is a practical and useful technique that provides useful insights into the dynamics of adoption of socially desirable products such as contraceptives.

  12. Urban geochemistry: research strategies to assist risk assessment and remediation of brownfield sites in urban areas.

    Science.gov (United States)

    Thornton, I; Farago, M E; Thums, C R; Parrish, R R; McGill, R A R; Breward, N; Fortey, N J; Simpson, P; Young, S D; Tye, A M; Crout, N M J; Hough, R L; Watt, J

    2008-12-01

    Urban geochemical maps of Wolverhampton and Nottingham, based on multielement analysis of surface soils, have shown distribution patterns of "total" metals concentrations relating to past and present industrial and domestic land use and transport systems. Several methods have been used to estimate the solubility and potential bioavailability of metals, their mineral forms and potential risks to urban population groups. These include sequential chemical extraction, soil pore water extraction and analysis, mineralogical analysis by scanning electron microscopy, source apportionment by lead isotope analysis and the development of models to predict metal uptake by homegrown vegetables to provide an estimate of risk from metal consumption and exposure. The results from these research strategies have been integrated with a geographical information system (GIS) to provide data for future land-use planning.

  13. A study of seismology as a dynamic, distributed area of scientific research

    CERN Document Server

    Wagner, Caroline S

    2009-01-01

    Seismology has several features that suggest it is a highly internationalized field: the subject matter is global, the tools used to analyse seismic waves are dependent upon information technologies, and governments are interested in funding cooperative research. We explore whether an emerging field like seismology has a more internationalised structure than the older, related field of geophysics. Using aggregated journal-journal citations, we first show that, within the citing environment, seismology emerged from within geophysics as its own field in the 1990s. The bibliographic analysis, however, does not show that seismology is more internationalised than geophysics: in 2000, seismology had a lower percentage of all articles co-authored on an international basis. Nevertheless, social network analysis shows that the core group of cooperating countries within seismology is proportionately larger and more distributed than that within geophysics. While the latter exhibits an established network with a hierarch...

  14. A quantitative flood risk analysis methodology for urban areas with integration of social research data

    Science.gov (United States)

    Escuder-Bueno, I.; Castillo-Rodríguez, J. T.; Zechner, S.; Jöbstl, C.; Perales-Momparler, S.; Petaccia, G.

    2012-09-01

    Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009-2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative). First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

  15. A quantitative flood risk analysis methodology for urban areas with integration of social research data

    Directory of Open Access Journals (Sweden)

    I. Escuder-Bueno

    2012-09-01

    Full Text Available Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009–2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative. First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

  16. Social and economic research program for the Geysers-Calistoga known geothermal resource area

    Energy Technology Data Exchange (ETDEWEB)

    Hall, C.; O' Banion, K.

    1979-03-27

    The purpose of this study is to assess the economic and social effects of projected geothermal resource development for both direct use and electric power generation and to analyze local regulatory policy options designed to mitigate adverse effects. The key issues are land use, fiscal and public infrastructure systems, demography, and the local economy. The study has seven elements: a computer-based inventory and analysis of land characteristics, constraints, sensitivity, and suitability for various land uses; projections of direct and electric geothermal development; primary and induced economic activity using an input-output model; demographic changes; the land and infrastructural demand created; an assessment of the economic and social effects of various configurations in land use that could result; and an analysis of various local regulatory policy options to mitigate adverse effects. The study is a cooperative effort among two national laboratories, a regional agency, and the four Geysers-area counties (Lake, Mendocino, Napa, and Sonoma). The assessment results are intended to guide Department of Energy planners on the environmental consequences of program implementation. The regulatory policy analysis is intended for local officials who are implementing development-management policy.

  17. Effect of hydrophilic coating on microorganism colonization in silicone tubing.

    Science.gov (United States)

    Cağavi, F; Akalan, N; Celik, H; Gür, D; Güçiz, B

    2004-06-01

    Shunt infections are one of the major causes of mortality and morbidity of patients with hydrocephalus. The aim of this research is to compare the bacterial colonization characteristics of a regular silicone elastomer shunt material coated with polyvinylpyrrolidone and dimethylpolysiloxane (silicone). Regular coated shunt materials were compared by in-vivo and in-vitro methods. In the in-vitro experiment, silicone and coated material immersed and not immersed in vancomycin solution was treated with a certain concentration of Staphylococcus epidermidis. In the in-vivo study, silicone and coated material specimens were treated with Staphylococcus epidermidis and they were stereotactically placed in the lateral ventricles of the rats. One week after the inoculation, shunt pieces were removed and the colonies were counted by using a scanning electron microscope. There was a statistically significant difference of colonization in the in-vitro groups in coated material vs. silicone, coated material vs. vancomycin treated silicone, vancomycin treated coated material vs. silicone, vancomycin treated coated material vs. vancomycin treated silicone. There was no statistically significant difference for colonization in in-vitro groups of coated material and vancomycin treated coated material. With in-vivo experiments we can say that, coated material catheters are superior than the silicone catheters in respect to colonization but after the bacterial colonization has occurred, the amount of colonization did not differ. Coated material catheters are superior to silicone catheters and they prevent bacterial colonization in some respect. Copyright 2004 Springer-Verlag

  18. Advances in silicon nanophotonics

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher; Pu, Minhao

    plasma effect have been tested up to 40 Gbit/s, and hybrid evanescent silicon lasers have been realized both in the form of distributed feed-back lasers and micro-disk lasers. For enhancing the impact of silicon photonics in future ultrafast and energy-efficient all-optical signal processing, e......Silicon has long been established as an ideal material for passive integrated optical circuitry due to its high refractive index, with corresponding strong optical confinement ability, and its low-cost CMOS-compatible manufacturability. However, the inversion symmetry of the silicon crystal lattice...... has been an obstacle for a simple realization of electro-optic modulators, and its indirect band gap has prevented the realization of efficient silicon light emitting diodes and lasers. Still, significant progress has been made in the past few years. Electro-optic modulators based on the free carrier...

  19. Silicone-containing composition

    Science.gov (United States)

    Mohamed, Mustafa

    2012-01-24

    A silicone-containing composition comprises the reaction product of a first component and an excess of an isocyanate component relative to the first component to form an isocyanated intermediary. The first component is selected from one of a polysiloxane and a silicone resin. The first component includes a carbon-bonded functional group selected from one of a hydroxyl group and an amine group. The isocyanate component is reactive with the carbon-bonded functional group of the first component. The isocyanated intermediary includes a plurality of isocyanate functional groups. The silicone-containing composition comprises the further reaction product of a second component, which is selected from the other of the polysiloxane and the silicone resin. The second component includes a plurality of carbon-bonded functional groups reactive with the isocyanate functional groups of the isocyanated intermediary for preparing the silicone-containing composition.

  20. Intraventricular Silicone Oil

    Science.gov (United States)

    Mathis, Stéphane; Boissonnot, Michèle; Tasu, Jean-Pierre; Simonet, Charles; Ciron, Jonathan; Neau, Jean-Philippe

    2016-01-01

    Abstract Intracranial silicone oil is a rare complication of intraocular endotamponade with silicone oil. We describe a case of intraventricular silicone oil fortuitously observed 38 months after an intraocular tamponade for a complicated retinal detachment in an 82 year-old woman admitted in the Department of Neurology for a stroke. We confirm the migration of silicone oil along the optic nerve. We discuss this rare entity with a review of the few other cases reported in the medical literature. Intraventricular migration of silicone oil after intraocular endotamponade is usually asymptomatic but have to be known of the neurologists and the radiologists because of its differential diagnosis that are intraventricular hemorrhage and tumor. PMID:26735537

  1. 2016 Energetic Materials Gordon Research Conference and Gordon Research Seminar Research Area 7: Chemical Sciences 7.0 Chemical Sciences (Dr. James K. Parker)

    Science.gov (United States)

    2016-08-10

    sources , gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden...Rachel Huber (Los Alamos National Laboratory, USA) "The Role of Atmosphere in Nanocarbon Formation Under Extreme Conditions for Detonation of...Lunch 1:30 pm - 2:30 pm Mentorship Component: Careers in Energetic Materials Research Discussion Leaders: Rachel Huber (Los Alamos National

  2. Silicon germanium mask for deep silicon etching

    KAUST Repository

    Serry, Mohamed

    2014-07-29

    Polycrystalline silicon germanium (SiGe) can offer excellent etch selectivity to silicon during cryogenic deep reactive ion etching in an SF.sub.6/O.sub.2 plasma. Etch selectivity of over 800:1 (Si:SiGe) may be achieved at etch temperatures from -80 degrees Celsius to -140 degrees Celsius. High aspect ratio structures with high resolution may be patterned into Si substrates using SiGe as a hard mask layer for construction of microelectromechanical systems (MEMS) devices and semiconductor devices.

  3. Review of Occupational Therapy Intervention Research in the Practice Area of Children and Youth 2009–2013

    Science.gov (United States)

    Bendixen, Roxanna M.; Huang, Yu Yun; Lim, Yoonjeong

    2014-01-01

    PURPOSE. We conducted a systematic review examining the extent to which pediatric intervention research recently published in the American Journal of Occupational Therapy reflects occupational therapy’s holistic occupation-based tenets. METHOD. We surveyed 10 systematic reviews and analyzed 38 single effectiveness studies for intervention approach, type, level of environmental targeting, level of occupational task and participation practice, and measures used. RESULTS. Of the 38 single effectiveness studies, 12 (32%) explicitly incorporated both environmental targets of intervention and practice of complex or in vivo occupational tasks, with steady increases during the 2009–2013 time frame. CONCLUSION. In the area of children and youth, occupational therapy is making steady gains in reflecting and demonstrating the effectiveness of the profession’s holistic, occupation-based tenets. Occupational therapy researchers must be mindful to ensure that despite the reductionist nature of intervention research, interventions reflect the profession’s holistic understanding of the interplay between the child, environment, and occupations. PMID:24581415

  4. The DAMPE silicon tungsten tracker

    CERN Document Server

    Gallo, Valentina; Asfandiyarov, R; Azzarello, P; Bernardini, P; Bertucci, B; Bolognini, A; Cadoux, F; Caprai, M; Domenjoz, M; Dong, Y; Duranti, M; Fan, R; Franco, M; Fusco, P; Gargano, F; Gong, K; Guo, D; Husi, C; Ionica, M; Lacalamita, N; Loparco, F; Marsella, G; Mazziotta, M N; Mongelli, M; Nardinocchi, A; Nicola, L; Pelleriti, G; Peng, W; Pohl, M; Postolache, V; Qiao, R; Surdo, A; Tykhonov, A; Vitillo, S; Wang, H; Weber, M; Wu, D; Wu, X; Zhang, F; De Mitri, I; La Marra, D

    2017-01-01

    The DArk Matter Particle Explorer (DAMPE) satellite has been successfully launched on the 17th December 2015. It is a powerful space detector designed for the identification of possible Dark Matter signatures thanks to its capability to detect electrons and photons with an unprecedented energy resolution in an energy range going from few GeV up to 10 TeV. Moreover, the DAMPE satellite will contribute to a better understanding of the propagation mechanisms of high energy cosmic rays measuring the nuclei flux up to 100 TeV. DAMPE is composed of four sub-detectors: a plastic strip scintillator, a silicon-tungsten tracker-converter (STK), a BGO imaging calorimeter and a neutron detector. The STK is made of twelve layers of single-sided AC-coupled silicon micro-strip detectors for a total silicon area of about 7 $m^2$ . To promote the conversion of incident photons into electron-positron pairs, tungsten foils are inserted into the supporting structure. In this document, a detailed description of the STK constructi...

  5. Undergraduate Research at a Minority University: Studying the Atmospheric Conditions in Urban vs. Rural Areas

    Science.gov (United States)

    Morris, P. A.; Green Garcia, A.; Hromis, A.; Vaquiz, E.; Wright, J. M.; Austin, S. A.; Johnson, L. P.; Musselwhite, D.; Walter, D.

    2009-12-01

    A grant from the National Science Foundation (NFS) funded a three year atmospheric science program known as the Minority University Consortium for Earth and Space Science (MUCESS) that supports undergraduate research programs devoted to studying ozone (O3) profiles. MUCESS institutions are represented by the University of Houston-Downtown (UHD), Medgar Evers College of the City University of New York (MEC), and South Carolina State University (SCSU). The primary strength of the program lies in the fact that it provides a venue for students from the participating minority institutions to build bridges of dialogue and strengthen research capabilities. A secondary strength of MUCESS is that the collaborative institutions are widely separated geographically but they have excellent communications and the ability to coordinate launches and support annual workshops. MUCESS supported a series of ozonesonde launches from multiple sites between April and July 2009. Both urban and rural sites were chosen based on their proximity to the three participating minority universities. Balloon and ozone monitoring technology facilitated data acquisition from cost-effective, environmentally friendly, and reproducible experiments. Payloads consisting of an ozonesonde, Vaisala® radiosonde, and GPS receiver provided information on dynamic atmospheric conditions that exist from ground level through altitudes up to one hundred thousand feet. Preparations for the collaborative launch included an initial calibration phase where identical calibration procedures prepared all three payloads. This calibration phase was performed five to seven days in advance of the launch. An additional calibration was performed the day of launch to verify communications between in-flight and ground radio transmitter and receiver, as well as to validate partial pressure and O3 concentration output from the ozonesonde. Each payload was tethered to a 600 gram weather balloon which was then carried up to the

  6. Brittle materials at high-loading rates: an open area of research

    Science.gov (United States)

    Forquin, Pascal

    2017-01-01

    Brittle materials are extensively used in many civil and military applications involving high-strain-rate loadings such as: blasting or percussive drilling of rocks, ballistic impact against ceramic armour or transparent windshields, plastic explosives used to damage or destroy concrete structures, soft or hard impacts against concrete structures and so on. With all of these applications, brittle materials are subjected to intense loadings characterized by medium to extremely high strain rates (few tens to several tens of thousands per second) leading to extreme and/or specific damage modes such as multiple fragmentation, dynamic cracking, pore collapse, shearing, mode II fracturing and/or microplasticity mechanisms in the material. Additionally, brittle materials exhibit complex features such as a strong strain-rate sensitivity and confining pressure sensitivity that justify expending greater research efforts to understand these complex features. Currently, the most popular dynamic testing techniques used for this are based on the use of split Hopkinson pressure bar methodologies and/or plate-impact testing methods. However, these methods do have some critical limitations and drawbacks when used to investigate the behaviour of brittle materials at high loading rates. The present theme issue of Philosophical Transactions A provides an overview of the latest experimental methods and numerical tools that are currently being developed to investigate the behaviour of brittle materials at high loading rates. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

  7. The energy investment decision in the nonresidential building sector: Research into the areas of influence

    Energy Technology Data Exchange (ETDEWEB)

    Harkreader, S.A.; Ivey, D.L.

    1987-04-01

    The purpose of this report is to describe and to characterize the decision process in the nonresidential building sector as well as the variables influencing energy investment decisions, both of which impact the development of R and D agendas for the Office of Building and Community Systems (BCS). The report reviews the available information on the factors that influence energy investment decisions and identifies information gaps where additional research is needed. This report focuses on variables and combinations of these variables (descriptive states) that influence the non residential energy investment decision maker. Economic and demographic descriptors, energy investment decision maker characteristics, and variables affecting energy investments are identified. This response examines the physical characteristics of buildings, characteristics of the legal environment surrounding buildings, demographic factors, economic factors, and decision processes, all of which impact the nonresidential energy investment market. The emphasis of the report is on providing possible methodologies for projecting the future of the nonresidential energy investment market, as well as, collecting the data necessary for such projections. The use of alternate scenarios is suggested as a projection tool and suggestions for collecting the appropriate data are made in the recommendations.

  8. Using integrated research and interdisciplinary science: Potential benefits and challenges to managers of parks and protected areas

    Science.gov (United States)

    van Riper, Charles; Powell, Robert B.; Machlis, Gary; van Wagtendonk, Jan W.; van Riper, Carena J.; von Ruschkowski, Eick; Schwarzbach, Steven E.; Galipeau, Russell E.

    2012-01-01

    Our purpose in this paper is to build a case for utilizing interdisciplinary science to enhance the management of parks and protected areas. We suggest that interdisciplinary science is necessary for dealing with the complex issues of contemporary resource management, and that using the best available integrated scientific information be embraced and supported at all levels of agencies that manage parks and protected areas. It will take the commitment of park managers, scientists, and agency leaders to achieve the goal of implementing the results of interdisciplinary science into park management. Although such calls go back at least several decades, today interdisciplinary science is sporadically being promoted as necessary for supporting effective protected area management(e.g., Machlis et al. 1981; Kelleher and Kenchington 1991). Despite this history, rarely has "interdisciplinary science" been defined, its importance explained, or guidance provided on how to translate and then implement the associated research results into management actions (Tress et al. 2006; Margles et al. 2010). With the extremely complex issues that now confront protected areas (e.g., climate change influences, extinctions and loss of biodiversity, human and wildlife demographic changes, and unprecedented human population growth) information from more than one scientific discipline will need to be brought to bear in order to achieve sustained management solutions that resonate with stakeholders (Ostrom 2009). Although interdisciplinary science is not the solution to all problems, we argue that interdisciplinary research is an evolving and widely supported best practice. In the case of park and protected area management, interdisciplinary science is being driven by the increasing recognition of the complexity and interconnectedness of human and natural systems, and the notion that addressing many problems can be more rapidly advanced through interdisciplinary study and analysis.

  9. Using a Bayesian network to clarify areas requiring research in a host-pathogen system.

    Science.gov (United States)

    Bower, D S; Mengersen, K; Alford, R A; Schwarzkopf, L

    2017-12-01

    Bayesian network analyses can be used to interactively change the strength of effect of variables in a model to explore complex relationships in new ways. In doing so, they allow one to identify influential nodes that are not well studied empirically so that future research can be prioritized. We identified relationships in host and pathogen biology to examine disease-driven declines of amphibians associated with amphibian chytrid fungus (Batrachochytrium dendrobatidis). We constructed a Bayesian network consisting of behavioral, genetic, physiological, and environmental variables that influence disease and used them to predict host population trends. We varied the impacts of specific variables in the model to reveal factors with the most influence on host population trend. The behavior of the nodes (the way in which the variables probabilistically responded to changes in states of the parents, which are the nodes or variables that directly influenced them in the graphical model) was consistent with published results. The frog population had a 49% probability of decline when all states were set at their original values, and this probability increased when body temperatures were cold, the immune system was not suppressing infection, and the ambient environment was conducive to growth of B. dendrobatidis. These findings suggest the construction of our model reflected the complex relationships characteristic of host-pathogen interactions. Changes to climatic variables alone did not strongly influence the probability of population decline, which suggests that climate interacts with other factors such as the capacity of the frog immune system to suppress disease. Changes to the adaptive immune system and disease reservoirs had a large effect on the population trend, but there was little empirical information available for model construction. Our model inputs can be used as a base to examine other systems, and our results show that such analyses are useful tools for

  10. Emerging areas of research reported during the CDC National Conference on Pfiesteria: from biology to public health.

    Science.gov (United States)

    Rubin, C; McGeehin, M A; Holmes, A K; Backer, L; Burreson, G; Earley, M C; Griffith, D; Levine, R; Litaker, W; Mei, J; Naeher, L; Needham, L; Noga, E; Poli, M; Rogers, H S

    2001-10-01

    Since its identification in 1996, the marine dinoflagellate Pfiesteria piscicida Steidinger & Burkholder has been the focus of intense scientific inquiry in disciplines ranging from estuarine ecology to epidemiology and from molecular biology to public health. Despite these research efforts, the extent of human exposure and the degree of human illness directly associated with Pfiesteria is still in the process of being defined. Unfortunately, during this same time Pfiesteria has also stimulated media coverage that in some instances jumped ahead of the science to conclude that Pfiesteria presents a widespread threat to human health. Political and economic forces also came into play when the tourism and seafood industries were adversely impacted by rumors of toxin-laden water in estuaries along the east coast of the United States. Amid this climate of evolving science and public concern, Pfiesteria has emerged as a highly controversial public health issue. In October 2000 Centers for Disease Control and Prevention sponsored the National Conference on Pfiesteria: From Biology to Public Health to bring together Pfiesteria researchers from many disparate disciplines. The goal of this meeting was to describe the state of the science and identify directions for future research. In preparation for the conference an expert peer-review panel was commissioned to review the existing literature and identify research gaps; the summary of their review is published in this monograph. During the meeting primary Pfiesteria researchers presented previously unpublished results. The majority of those presentations are included as peer-reviewed articles in this monograph. The discussion portion of the conference focused upon researcher-identified research gaps. This article details the discussion segments of the conference and makes reference to the presentations as it describes emerging areas of Pfiesteria research.

  11. A brief review of recent developments in the designs that prevent bio-fouling on silicon and silicon-based materials.

    Science.gov (United States)

    Zhang, Xiaoning; Brodus, DaShan; Hollimon, Valerie; Hu, Hongmei

    2017-01-01

    Silicon and silicon-based materials are essential to our daily life. They are widely used in healthcare and manufacturing. However, silicon and silicon-based materials are susceptible to bio-fouling, which is of great concern in numerous applications. To date, interdisciplinary research in surface science, polymer science, biology, and engineering has led to the implementation of antifouling strategies for silicon-based materials. However, a review to discuss those antifouling strategies for silicon-based materials is lacking. In this article, we summarized two major approaches involving the functionalization of silicon and silicon-based materials with molecules exhibiting antifouling properties, and the fabrication of silicon-based materials with nano- or micro-structures. Both approaches lead to a significant reduction in bio-fouling. We critically reviewed the designs that prevent fouling due to proteins, bacteria, and marine organisms on silicon and silicon-based materials. Graphical abstractStrategies used in the designs that prevent bio-fouling on silicon and silicon-based materials.

  12. Optimization of time–temperature schedule for nitridation of silicon ...

    Indian Academy of Sciences (India)

    compact on the basis of silicon and nitrogen reaction kinetics. J RAKSHIT and P K DAS*. Central Glass and Ceramic Research Institute, Jadavpur, Calcutta 700 032, India. MS received 27 March 2000; revised 1 June 2000. Abstract. A time–temperature schedule for formation of silicon–nitride by direct nitridation of silicon ...

  13. A Cost Roadmap for Silicon Heterojunction Solar Cells

    NARCIS (Netherlands)

    Louwen, A.|info:eu-repo/dai/nl/375268456; van Sark, W.G.J.H.M.|info:eu-repo/dai/nl/074628526; Schropp, Ruud; Faaij, A.

    Research and development of silicon heterojunction (SHJ) solar cells has seen a marked increase since the recent expiry of core patents describing SHJ technology. SHJ solar cells are expected to offer various cost benefits compared to conventional crystalline silicon solar cells. This paper analyses

  14. Silicon and silicide nanowires applications, fabrication, and properties

    CERN Document Server

    Tu, King-Ning

    2013-01-01

    This book comprises theoretical and experimental analysis of various properties of silicon nanocrystals, research methods and preparation techniques, and some promising applications. It comprises nine chapters. The first three are based on processing, the next three on properties, and the last three on applications of nanowires of silicon and silicides.

  15. ENTREPRENEURSHIP AS A FACTOR OF THE RURAL AREAS DEVELOPMENT – THE RESULTS OF RESEARCH AT THE LOCAL AND REGIONAL LEVEL

    Directory of Open Access Journals (Sweden)

    Grażyna Adamczyk-Łojewska

    2016-03-01

    Full Text Available The article presents the results of research concerning natural persons conducting economic activity registered in the REGON system that characterize the development of entrepreneurship in rural areas in Poland in the post-accession period. The main objective of this study was to identify the development tendencies and territorial diff erentiation in the range of the analysed form of economic activity. The research was conducted using computer local data banks (BDL published by Central Statistical Offi ce of Poland, and also the techniques of GIS (Geographic Information Systems to depict parts of the results in the form of thematic maps. The analysis of registered natural persons in relation to the population (per 100 inhabitants was carried out at the two levels: local (in all municipalities in the country for 2003–2012, as well as regional level (for 16 voivodeships for 2003–2014. The research pointed to an increase of the importance of economic entrepreneurship in development of rural areas, and at the same time it showed a large territorial diff erentiation in this respect.

  16. The level of health in Elementary School Students in Training and Research Areas and Evaluation of School Screening Examination Results

    Directory of Open Access Journals (Sweden)

    Cemalettin Kalyoncu

    2011-10-01

    Full Text Available AIM: The research was planned in order to evaluate the level of health’s elementary schools located in Eskisehir Osmangazi University School of Medicine Public Health Department Training and Research Areas and the school health services they have been receiving for the last eight years. METHOD: 1st, 2nd, 7th and 8th grade students studying in 12 elementary schools located in the Training and Research Areas in 2009-2010 academic year were enrolled to the study. On days of the screenings, a total of 1405 students available (1405/1569: %89.5 in the schools were reached. Growth, seeing, hearing, mouth-teeth health, systemic physical examination and by consulting to the teachers, state of mind and existence of chronic diseases were researched. For each child, information containing the existence of school enrolment examination, the number of periodic examinations that have been conducted on the child, and also the results of the examination of the same year was inquired. RESULTS: 1.0 % of the students were detected as very weak, 4.8 % as weak, 75.9 % as normal, 15.8 % as overweight and 2.5 % as obese. In eye examinations, 10.5% of the students had refractive error, 6.2 % had amblyopia and 3.1% had diplopia. In the ear examination, it was determined that 48.7 % of the students had plug, 2.5 % had perforated tympanum, and 3.1 % had hearing loss. In mouth and teeth examination, it was detected that 64.8% of the students had tooth decay. All of the students who were claimed to have undergone school enrolment examination were first grade students and that examinations included examination results of this year. Health forms containing the results of school enrolment examination and periodic examinations of 2nd, 7th and 8th grade students were not found. School screening were conducted only in two district elementary schools. The eye examination results reported in the records appeared to be inconsistent with screning results. CONCLUSION: It was shown

  17. Role of water in the tribochemical removal of bare silicon

    Science.gov (United States)

    Chen, Cheng; Xiao, Chen; Wang, Xiaodong; Zhang, Peng; Chen, Lei; Qi, Yaqiong; Qian, Linmao

    2016-12-01

    Nanowear tests of bare silicon against a SiO2 microsphere were conducted in air (relative humidity [RH] = 0%-89%) and water using an atomic force microscope. Experimental results revealed that the water played an important role in the tribochemical wear of the bare silicon. A hillock-like wear trace with a height of 0.7 nm was generated on the bare silicon surface in dry air. As the RH increased, the wear depth increased and reached the maximum level in water. Analysis of frictional dissipated energy suggested that the wear of the bare silicon was not dominated by mechanical interactions. High-resolution transmission electron microscopy detection demonstrated that the silicon atoms and crystal lattice underneath the worn area maintained integral perfectly and thus further confirmed the tribochemical wear mechanism of the bare silicon. Finally, the role of water in the tribochemical wear of the bare silicon may be explained by the following three aspects: the hydroxylation by hydroxyl ions auto-ionized in water, the hydrolytic reaction of water molecules, and the dissolution of the tribochemical product SiOmHn in liquid water. With increasing RH, a greater water amount would adsorb to the Si/SiO2 interface and induce a more serious tribochemical wear on the bare silicon surface. The results of this paper may provide further insight into the tribochemical removal mechanism of bare monocrystalline silicon and furnish the wider reaction cognition for chemical mechanical polishing.

  18. Silicon nanowire hybrid photovoltaics

    KAUST Repository

    Garnett, Erik C.

    2010-06-01

    Silicon nanowire Schottky junction solar cells have been fabricated using n-type silicon nanowire arrays and a spin-coated conductive polymer (PEDOT). The polymer Schottky junction cells show superior surface passivation and open-circuit voltages compared to standard diffused junction cells with native oxide surfaces. External quantum efficiencies up to 88% were measured for these silicon nanowire/PEDOT solar cells further demonstrating excellent surface passivation. This process avoids high temperature processes which allows for low-cost substrates to be used. © 2010 IEEE.

  19. Silicon tracker for LHC

    Energy Technology Data Exchange (ETDEWEB)

    Bencze, G.; Bosteels, M.; Brenner, R.; Czellar, S.; Ekman, K.; Hentinen, A.; Hietanen, I.; Huhtinen, M.; Inkinen, S.; Karimaeki, V.; Karttaavi, T.; Kinnunen, R.; Lindgren, J.; Merlo, J.P.; Oksakivi, T.; Onnela, A.; Orava, R.; Pietarinen, E.; Pimiae, M.; Roth, W.; Roennqvist, C.; Saarikko, J.P.; Schulman, T.; Tuuva, T.; Voutilainen, M.; Vuoskoski, J.; Oesterberg, K. (Research Inst. for High Energy Physics, SEFT, Helsinki (Finland) Physics Dept., Univ. of Helsinki (Finland) Univ. of Technology, Helsinki, Espoo (Finland) AAbo Akademi, Domkyrkotorget, Turku (Finland) Univ. of Technology, Tampere (Finland) DAPNIA, Centre d' Etudes Nucleaires, 91 Gif-sur-Yvette, Saclay (France) CERN, Geneva (Switzerland))

    1993-05-01

    A study of a possible layout of a Silicon tracker has been done. The design is based on simulations done in the context of the Compact Muon Solenoid (CMS) detector for the LHC. The high granularity of the silicon strip detectors yields to low occupancies. New type of a silicon strip detector, single sided stereo angle detector (SSSD), has been designed to match the requirements of a LHC tracker. This detector allows a z-coordinate measurement without increasing the number of channels i.e. power consumption and it facilitates a tracker design with reasonable complicity. (orig.)

  20. Amorphous silicon for thin-film transistors

    NARCIS (Netherlands)

    Schropp, Rudolf Emmanuel Isidore

    1987-01-01

    Hydrogenated amorphous silicon (a-Si:H) has considerable potential as a semiconducting material for large-area photoelectric and photovoltaic applications. Moreover, a-Si:H thin-film transistors (TFT’s) are very well suited as switching devices in addressable liquid crystal display panels and

  1. Development of self-aligned gated porous silicon microtip field emission arrays for vacuum microelectronic applications

    Science.gov (United States)

    Jessing, Jeffrey Richard

    Solid state microelectronics is the dominate technology in the present day electronics industry. However, as the physical dimensions decrease, it is becoming apparent that solid state devices have inherent performance limitations, such as finite saturation drift velocity, high temperature degradation, and failure in extreme radiation environments. To address these problems a relatively new technology, called vacuum microelectronics, has emerged. Vacuum microelectronics encompasses the fabrication, characterization, and application of various devices whose operation is based on vacuum ballistic transport of field emitted electrons from microminiature electrodes. The field of vacuum microelectronics has advanced at a rapid rate over the past decade; however, there remain key issues to be addressed prior to any widespread commercialization of this technology. Field emission arrays (FEAs) must operate at low voltages and generate high current densities with uniform, long-lifetime operation. The use of porous silicon cathodes in vacuum microelectronic applications is a promising alternative to existing silicon and metal field emitters. Surface modification of bulk crystalline silicon by electrochemical anodization in a concentrated hydrofluoric acid (HF) solution has been shown to produce large submicroscopic field enhancement and large emission area. The primary focus of this research was the development of novel gated FEAs based on porous silicon microtip cathodes. Device design consisted of both experimental and theoretical efforts. Employing semiconductor process technology, the successful fabrication of an operational self-aligned gated porous silicon microtip FEA was demonstrated. Small arrays exhibited Fowler-Nordheim characteristics over several decades of anode current. A peak stable current of approximately 60 to 70 nA per tip was obtained at less than 125 V. A correlation of anodization conditions with emission properties has been found, and a simple emission

  2. Advanced silicon on insulator technology

    Science.gov (United States)

    Godbey, D.; Hughes, H.; Kub, F.

    1991-01-01

    Undoped, thin-layer silicon-on-insulator was fabricated using wafer bonding and selective etching techniques employing a molecular beam epitaxy (MBE) grown Si0.7Ge0.3 layer as an etch stop. Defect free, undoped 200-350 nm silicon layers over silicon dioxide are routinely fabricated using this procedure. A new selective silicon-germanium etch was developed that significantly improves the ease of fabrication of the bond and etch back silicon insulator (BESOI) material.

  3. USGS ecosystem research for the next decade: advancing discovery and application in parks and protected areas through collaboration

    Science.gov (United States)

    van Riper, Charles; Nichols, James D.; Wingard, G. Lynn; Kershner, Jeffrey L.; Cloern, James E.; Jacobson, Robert B.; White, Robin P.; McGuire, Anthony David; Williams, Byron K.; Gelfenbaum, Guy; Shapiro, Carl D.

    2014-01-01

    Ecosystems within parks and protected areas in the United States and throughout the world are being transformed at an unprecedented rate. Changes associated with natural hazards, greenhouse gas emissions, and increasing demands for water, food, land, energy and mineral resources are placing urgency on sound decision making that will help sustain our Nation’s economic and environmental well-being (Millennium Ecosystem Assessment, 2005). In recognition of the importance of science in making these decisions, the U.S. Geological Survey (USGS) in 2007 identified ecosystem science as one of six science directions included in a comprehensive decadal strategy (USGS 2007). The Ecosystems Mission Area was identified as essential for integrating activity within the USGS and as a key to enhanced integration with other Federal and private sector research and management organizations (Myers at al., 2007). This paper focuses on benefits to parks and protected areas from the USGS Ecosystems Mission Area plan that expanded the scope of the original 2007 science strategy, to identify the Bureau’s work in ecosystem science over the next decade (Williams et al., 2013). The plan describes a framework that encompasses both basic and applied science and allows the USGS to continue to contribute meaningfully to conservation and management issues related to the Nation’s parks and ecological resources. This framework relies on maintaining long-standing, collaborative relationships with partners in both conducting science and applying scientific results. Here we summarize the major components of the USGS Ecosystems Science Strategy, articulating the vision, goals and strategic approaches, then outlining some of the proposed actions that will ultimately prove useful to those managing parks and protected areas. We end with a discussion on the future of ecosystem science for the USGS and how it can be used to evaluate ecosystem change and the associated consequences to management of our

  4. Investigacion Educativa: Areas - Politicas - Estrategias y Proyectos del ICOLPE, 2 (Educational Research: Topics, Policies, Strategies, and Projects of the Colombian Institute of Pedagogy, 2),

    Science.gov (United States)

    Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.

    This booklet defines and establishes guidelines for educational research in Colombia. Sections describe basic philosophy and objectives, types of research, policies for educational investigation, governmental role, and principle areas for educational research. A listing of current and proposed research projects is provided. The final section…

  5. Silicon nanomaterials platform for bioimaging, biosensing, and cancer therapy.

    Science.gov (United States)

    Peng, Fei; Su, Yuanyuan; Zhong, Yiling; Fan, Chunhai; Lee, Shuit-Tong; He, Yao

    2014-02-18

    biomedical applications, including biosensor, bioimaging, and cancer therapy. First, we show that the interesting photoluminescence properties (e.g., strong fluorescence and robust photostability) and excellent biocompatibility of silicon nanoparticles (SiNPs) are superbly suitable for direct and long-term visualization of biological systems. The strongly fluorescent SiNPs are highly effective for bioimaging applications, especially for long-term cellular labeling, cancer cell detection, and tumor imaging in vitro and in vivo with high sensitivity. Next, we discuss the utilization of silicon nanomaterials to construct high-performance biosensors, such as silicon-based field-effect transistors (FET) and surface-enhanced Raman scattering (SERS) sensors, which hold great promise for ultrasensitive and selective detection of biological species (e.g., DNA and protein). Then, we introduce recent exciting research findings on the applications of silicon nanomaterials for cancer therapy with encouraging therapeutic outcomes. Lastly, we highlight the major challenges and promises in this field, and the prospect of a new nanobiotechnology platform based on silicon nanomaterials.

  6. Superhydrophobic silicone fiber mats fabricated by electrospinning from solution

    Science.gov (United States)

    Ludwig, Bonnie; Clark, Aneta; Snow, Steven; Hill, Randal; Schmidt, Randall; Fogg, Brad; Lo, Peter

    2007-03-01

    Fine silicone fibers of 1 -- 20 μm diameter were fabricated from solution via electrospinning. These are the first examples of fine fibers prepared from silicone homopolymers. Fiber morphology (beaded, ribbon-like, smooth) and diameter were controlled. The nanoscale surface roughness of nonwoven fiber mats created with silicone fibers produced a superhydrophobic surface that had a water contact angle of ˜160^o. The superhydrophobic surface was made reversibly hydrophilic with exposure to oxygen plasma. The combination of high surface area and superhydrophobicity suggests potential applications in the areas of water-repellent textiles, filtration, adsorption and chemical separations, wound dressings, and fuel cells.

  7. Note: Anodic bonding with cooling of heat-sensitive areas

    DEFF Research Database (Denmark)

    Vesborg, Peter Christian Kjærgaard; Olsen, Jakob Lind; Henriksen, Toke Riishøj

    2010-01-01

    Anodic bonding of silicon to glass always involves heating the glass and device to high temperatures so that cations become mobile in the electric field. We present a simple way of bonding thin silicon samples to borosilicate glass by means of heating from the glass side while locally cooling heat......-sensitive areas from the silicon side. Despite the high thermal conductivity of silicon, this method allows a strong anodic bond to form just millimeters away from areas essentially at room temperature....

  8. Silicon microfabricated beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A., E-mail: aliman@ppinang.uitm.edu.my; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A. [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40450, Shah Alam, Selangor (Malaysia); Ain, M. F. [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300,Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-30

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  9. ALICE Silicon Pixel Detector

    CERN Multimedia

    2003-01-01

    The Silicon Pixel Detector (SPD) is part of the Inner Tracking System (ITS) of the ALICE experiment : . SPD Structure . Bump Bonding . Test beam . ALICE1LHCb Readout Chip . Chip Tests . Data from the SPD

  10. Silicon production process evaluations

    Science.gov (United States)

    1982-05-01

    Engineering design of the third distillation column in the process was accomplished. The initial design is based on a 94.35% recovery of dichlorosilane in the distillate and a 99.9% recovery of trichlorosilane in the bottoms. The specified separation is achieved at a reflux ratio of 15 with 20 trays (equilibrium stages). Additional specifications and results are reported including equipment size, temperatures and pressure. Specific raw material requirements necessary to produce the silicon in the process are presented. The primary raw materials include metallurgical grade silicon, silicon tetrachloride, hydrogen, copper (catalyst) and lime (waste treatment). Hydrogen chloride is produced as by product in the silicon deposition. Cost analysis of the process was initiated during this reporting period.

  11. Enamel silicon and fluoride relationships demonstrating a surface silicon effect that facilitates fluoride uptake.

    Science.gov (United States)

    Levy, J S; Koritzer, R T

    1976-01-01

    This study indicated that a clear relationship exists between silicon and fluoride. We have also demonstrated a probable surface enamel silicon effect that increases fluoride uptake. The complex set of relationships described in the surface chemistry of calcium, tin, and zirconium with fluoride, hydroxide, phosphate, and other surface-occurring ions need not be considered to confuse the specific silicon-fluoride relationship presented here because in this computation we are relating the changes in the silicon and fluoride ion values only. We have, however, considered the thermodynamics of such reactions and intend to elaborate on it in a later publication. We are aware of the small depth of fluoride penetration into enamel after topical treatment Health Foundation, Research Unit at the National Bureau of Standards, Washington, DC 20034, USA.

  12. High-Index Contrast Silicon Rich Silicon Nitride Optical Waveguides and Devices

    DEFF Research Database (Denmark)

    Philipp, Hugh Taylor

    2004-01-01

    This research focused on the realization of high-density integrated optical devices made with high-index contrast waveguides. The material platform used for to develop these devices was modeled after standard silicon on silicon technology. The high-index waveguide core material was silicon rich...... silicon nitride. This provided a sharp contrast with silica and made low-loss waveguide bending radii less than 25mm possible. An immediate consequence of such small bending radii is the ability to make practical ring resonator based devices with a large free spectral range. Several ring resonator based...... devices have been demonstrated. Directly UV-written waveguides have also been used with high-index contrast ring resonators to make hybrid devices. These hybrid devices are interesting because of the possibility of making practical low insertion-loss devices that utilize the benefits of a high...

  13. Investigation of migration of organic silicone into stone and its prevention; Silicone kei dansei secchakuzai no seibun ga sekizaichu ni shinto suru gensho no kyumei to shinto taisaku

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, M.; Sasaki, M. [Kajima Construction Co. Ltd., Tokyo (Japan)

    1998-07-30

    Quantitative analyses of silicone migration into marble from elastic silicon adhesive were carried out by EPMA and LMA, and the amount of migrated silicone was calculated in terms of silicone concentration. By EPMA, silicone distribution into the area centering around the boundary between elastic adhesive and marble was clarified, and the migrating condition of silicone from elastic adhesive to marble was made clear. In the case of LMA, silicone concentration in micro-area in marble was measured to use the measured result for the succeeding analyses. As a result of the analysis, the trend of the change of silicone migration with the passage of time could be expressed by treating the silicone migration as diffusion phenomenon, and the depth of silicone migration could be quantified. It was confirmed that the cover primer applied at the back of marble to inhibit migration could prevent contamination of marble caused by silicone migration. The analytical method of this study seemed to be applicable to other stone materials or other adhesive and sealing materials. 14 refs., 12 figs., 2 tabs.

  14. Workshop on Basic Research Opportunities in Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Benner, J.; McConnell, R.; Deb, S., Editors

    1999-08-25

    The Basic Research Opportunities in Photovoltaics Workshop was held on May 3, 1999, in Seattle, Washington, in conjunction with the 195th Meeting of the Electrochemical Society. The workshop was structured into eight topics. Each topic area opened with a presentation in which the participants were asked to address the following: a brief introduction of the area of research; key research issues that were identified in an earlier workshop in 1992; what fundamental research has been done since then or is currently being done to address those issues; what are the research issues that are still relevant in light of advances made since the first workshop; identification of new fundamental research opportunities that will lead to important advances and innovations; and identification of significant commonalities and common research issues that have a cross-cutting impact, such as logically exist in silicon-based thin films, II-VI, and related materials. The topic areas discussed included amorphous and microcrystalline silicon, crystalline silicon, cadmium telluride, copper indium diselenide; III-V materials; novel materials and energy conversion approaches, semiconducting oxides, and characterization. After the meeting, participants in each working topic continued discussions by electronic means, completing journal articles that are to be published as a separate section in the ECS Proceedings of the ''PV for the 21st Century'' Symposium.

  15. Research Natural Areas on National Forest System lands in Idaho, Montana, Nevada, Utah, and Western Wyoming: A guidebook for scientists, managers, and educators

    Science.gov (United States)

    Angela G. Evenden; Melinda Moeur; J. Stephen Shelly; Shannon F. Kimball; Charles A. Wellner

    2001-01-01

    This guidebook is intended to familiarize land resource managers, scientists, educators, and others with Research Natural Areas (RNAs) managed by the USDA Forest Service in the Northern Rocky Mountains and Intermountain West. This guidebook facilitates broader recognition and use of these valuable natural areas by describing the RNA network, past and current research...

  16. Contributions of Indian Council of Medical Research (ICMR) in the area of Medicinal plants/Traditional medicine.

    Science.gov (United States)

    Tandon, Neeraj; Yadav, Satyapal Singh

    2017-02-02

    Medicinal plants belong to the oldest known health care products that have been used by human beings all over the world and are major components of the formulations used in indigenous system of medicine practiced in many countries. Besides, finding place as health supplements, nutraceuticals, cosmetics, herbal tea etc. there has been a global insurgence of interest, including India, leading to enormous research/activities in the area of medicinal plants. The article is aimed to provide the effort and initiatives of ICMR towards research on medicinal plants and its contributions on consolidation of Indian research on medicinal plants that are very relevant and important in the national context. The various initiatives undertaken by ICMR on research on traditional medicines/medicinal plants in the past are reviewed and documented in this article. The multi-disciplinary, multicentric research initiatives of ICMR have resulted in validation of traditional treatment Kshaarasootra (medicated Ayurvedic thread) for anal fistula, Vijayasar (heart wood of Pterocarpus marsupium Roxb.) for diabetes mellitus, encouraging micro- and macrofilaricidal activity of Shakotak (stem bark of Streblus asper Lour.) in experimental studies an iridoid glycosides fraction isolated from root/rhizomes of Picrorhiza kurroa Royle ex Benth. (designated as Picroliv) for viral hepatitis. Other developmental and compilation of research works on Indian medicinal plants have resulted in publications of the thirteen volumes of quality standards, comprising of 449 Indian medicinal plants; three volumes of 90 phytochemical reference standards; fifteen volumes of review monographs on 4167 medicinal plant species; and one publication each on perspectives of Indian medicinal plants for management of liver disorders, lymphatic filariasis and diabetes mellitus (details available at http://www.icmr.nic.in/mpsite). The ICMR efforts assume special significance in the light of multifaceted use of medicinal plants

  17. Social aspects of revitalization of rural areas. Implementation of the rural revival programme in lodzkie voivodeship. Assumptions for sociological research

    Directory of Open Access Journals (Sweden)

    Pamela Jeziorska-Biel

    2012-04-01

    Full Text Available Essential elements of the process of rural renovation programme are: stimulating activity of local communities, cooperation for development, while preserving social identity, cultural heritage and natural environment. Implementing a rural revival programme in Poland: Sectoral Operational Programme “The Restructuring and Modernisation of the Food Sector and the Development of Rural Areas in 2004-2006” (action 2.3 “Rural renovation and protection and preservation of cultural heritage” evokes criticism. A wide discussion is carried amongst researchers, politicians, social activists, and local government practitioners. The main question remains: “is rural renovation process in Poland conducted in accordance with the rules in European countries or it is only a new formula of rural modernisation with the use of European funds?” The authors are joining the discussion and in the second part of the article they are presenting the assumption of sociological research. The aim of the analysis is to grasp the essence of revitalization of rural areas located in Łódzkie voivodeship, and analyse the question of specificity of rural Revival Programmes. What is the scope and manner of use of local capital? If so, are the results obtained from implementing a rural revival programme in 2004-2006 within the scope of sustainable development? What activities are predominant in the process of project implementation? Is it rural modernisation, revitalization of the rural areas, barrier removal and change in Infrastructure, or creation of social capital and subjectivity of the local community? Has the process of rural renovation in Łódzkie voivodeship got the so called “social face” and if so, to what extent? The major assumption is that rural renovation programme in Łódzkie voivodeship relates more to revitalization material aspects than “spirituality”.

  18. First Silicon Microdosimeters Based on Cylindrical Diodes

    Directory of Open Access Journals (Sweden)

    C. Guardiola

    2014-12-01

    Full Text Available Silicon detectors are used in many medical applications for particle tracking, X-ray medical imaging, gamma or X-ray spectrometry, among others. The development of new silicon detectors for specific physics areas leads to overcome technological challenges that means not only optimize the design, but also improve the micro-fabrication processes. A new design of a solid-state- detector based on silicon microfabrication is described in this work in order to create a novel microdosimeter. This microdosimeter improves the performance of existing microdosimeters using three-dimensional microfabrication technology development. The microdosimeter could help to obtain biophysical parameters necessary to elucidate the relative biological effectiveness in hadrontherapy as well as the equivalent dose of background radiations present in nuclear medicine, aerospace exploration, nuclear facilities, particle accelerator and aviation.

  19. Amorphous silicon crystalline silicon heterojunction solar cells

    CERN Document Server

    Fahrner, Wolfgang Rainer

    2013-01-01

    Amorphous Silicon/Crystalline Silicon Solar Cells deals with some typical properties of heterojunction solar cells, such as their history, the properties and the challenges of the cells, some important measurement tools, some simulation programs and a brief survey of the state of the art, aiming to provide an initial framework in this field and serve as a ready reference for all those interested in the subject. This book helps to "fill in the blanks" on heterojunction solar cells. Readers will receive a comprehensive overview of the principles, structures, processing techniques and the current developmental states of the devices. Prof. Dr. Wolfgang R. Fahrner is a professor at the University of Hagen, Germany and Nanchang University, China.

  20. Oxygen defect processes in silicon and silicon germanium

    KAUST Repository

    Chroneos, A.

    2015-06-18

    Silicon and silicon germanium are the archetypical elemental and alloy semiconductor materials for nanoelectronic, sensor, and photovoltaic applications. The investigation of radiation induced defects involving oxygen, carbon, and intrinsic defects is important for the improvement of devices as these defects can have a deleterious impact on the properties of silicon and silicon germanium. In the present review, we mainly focus on oxygen-related defects and the impact of isovalent doping on their properties in silicon and silicon germanium. The efficacy of the isovalent doping strategies to constrain the oxygen-related defects is discussed in view of recent infrared spectroscopy and density functional theory studies.

  1. Silicon-Based Light Sources for Silicon Integrated Circuits

    Directory of Open Access Journals (Sweden)

    L. Pavesi

    2008-01-01

    Full Text Available Silicon the material per excellence for electronics is not used for sourcing light due to the lack of efficient light emitters and lasers. In this review, after having introduced the basics on lasing, I will discuss the physical reasons why silicon is not a laser material and the approaches to make it lasing. I will start with bulk silicon, then I will discuss silicon nanocrystals and Er3+ coupled silicon nanocrystals where significant advances have been done in the past and can be expected in the near future. I will conclude with an optimistic note on silicon lasing.

  2. Research on Geo-information Data Model for Preselected Areas of Geological Disposal of High-level Radioactive Waste

    Science.gov (United States)

    Gao, M.; Huang, S. T.; Wang, P.; Zhao, Y. A.; Wang, H. B.

    2016-11-01

    The geological disposal of high-level radioactive waste (hereinafter referred to "geological disposal") is a long-term, complex, and systematic scientific project, whose data and information resources in the research and development ((hereinafter referred to ”R&D”) process provide the significant support for R&D of geological disposal system, and lay a foundation for the long-term stability and safety assessment of repository site. However, the data related to the research and engineering in the sitting of the geological disposal repositories is more complicated (including multi-source, multi-dimension and changeable), the requirements for the data accuracy and comprehensive application has become much higher than before, which lead to the fact that the data model design of geo-information database for the disposal repository are facing more serious challenges. In the essay, data resources of the pre-selected areas of the repository has been comprehensive controlled and systematic analyzed. According to deeply understanding of the application requirements, the research work has made a solution for the key technical problems including reasonable classification system of multi-source data entity, complex logic relations and effective physical storage structures. The new solution has broken through data classification and conventional spatial data the organization model applied in the traditional industry, realized the data organization and integration with the unit of data entities and spatial relationship, which were independent, holonomic and with application significant features in HLW geological disposal. The reasonable, feasible and flexible data conceptual models, logical models and physical models have been established so as to ensure the effective integration and facilitate application development of multi-source data in pre-selected areas for geological disposal.

  3. Laser-zone growth in a Ribbon-To-Ribbon (RTR) process. Silicon sheet growth development for the large area sheet task of the low-cost solar array project

    Science.gov (United States)

    Baghdadi, A.; Gurtler, R. W.; Legge, R.; Sopori, B.; Ellis, R. J.

    1978-01-01

    A new calculation of the effects of thermal stresses during growth on silicon ribbon quality is reported. Thermal stress distributions are computed for ribbon growth under a variety of temperature profiles. A growth rate of 55 cu cm/min with a single ribbon was achieved. The growth of RTR ribbon with a fairly uniform parallel dendritic structure was demonstrated. Results with two approaches were obtained for reducing the Mo impurity level in polycrystalline feedstock. Coating the Mo substrate with Si3N4 does not effect thermal shear separation of the polyribbon; this process shows promise of improving cell efficiency and also increasing the useful life of the molybdenum substrate. A number of solar cells were fabricated on RTR silicon grown from CVD feedstock.

  4. Silicon Based Anodes for Li-Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiguang; Wang, Wei; Xiao, Jie; Xu, Wu; Graff, Gordon L.; Yang, Zhenguo; Choi, Daiwon; Li, Xiaolin; Wang, Deyu; Liu, Jun

    2012-06-15

    Silicon is environmentally benign and ubiquitous. Because of its high specific capacity, it is considered one of the most promising candidates to replace the conventional graphite negative electrode used in today's Li ion batteries. Silicon has a theoretical specific capacity of nearly 4200 mAh/g (Li21Si5), which is 10 times larger than the specific capacity of graphite (LiC6, 372 mAh/g). However, the high capacity of silicon is associated with huge volume changes (more than 300 percent) when alloyed with lithium, which can cause severe cracking and pulverization of the electrode and lead to significant capacity loss. Significant scientific research has been conducted to circumvent the deterioration of silicon based anode materials during cycling. Various strategies, such as reduction of particle size, generation of active/inactive composites, fabrication of silicon based thin films, use of alternative binders, and the synthesis of 1-D silicon nanostructures have been implemented by a number of research groups. Fundamental mechanistic research has also been performed to better understand the electrochemical lithiation and delithiation process during cycling in terms of crystal structure, phase transitions, morphological changes, and reaction kinetics. Although efforts to date have not attained a commercially viable Si anode, further development is expected to produce anodes with three to five times the capacity of graphite. In this chapter, an overview of research on silicon based anodes used for lithium-ion battery applications will be presented. The overview covers electrochemical alloying of the silicon with lithium, mechanisms responsible for capacity fade, and methodologies adapted to overcome capacity degradation observed during cycling. The recent development of silicon nanowires and nanoparticles with significantly improved electrochemical performance will also be discussed relative to the mechanistic understanding. Finally, future directions on the

  5. Catastrophic Impact of Silicon on Silicon: Unraveling the Genesis Impact Using Sample 61881

    Science.gov (United States)

    Kuhlman, K. R.; Kim, H.; Jurewicz, A. J. G.; Gonzalez, C. P.; Allums, K. K.

    2016-01-01

    The Genesis mission collected solar wind and brought it back to Earth in order to provide precise knowledge of solar isotopic and elemental compositions. The ions in the solar wind were stopped in the collectors at depths on the order of 10 to a few hundred nanometers. This shallow implantation layer is critical for scientific analysis of the composition of the solar wind and must be preserved throughout sample handling, cleaning, processing, distribution, preparation and analysis. The current work is motivated by the need to understand the interaction of the Genesis payload with contamination during the crash in the Utah desert. Silicon contamination has been found to be notoriously difficult to remove from silicon samples despite multiple cleanings with multiple techniques. However, the question has been posed, "Does the silicon really need to be removed for large area analyses?." If the recalcitrant silicon contamination is all pure silicon from fractured collectors, only a very tiny fraction of that bulk material will contain solar wind, which could skew the analyses. This could be complicated if the silicon trapped other materials and/or gases as it impacted the surface.

  6. Nanoscale semiconducting silicon as a nutritional food additive

    Energy Technology Data Exchange (ETDEWEB)

    Canham, L T [pSiNutria Ltd, Malvern Hills Science Park, Geraldine Road, Malvern, Worcestershire WR14 3SZ (United Kingdom)

    2007-05-09

    Very high surface area silicon powders can be realized by high energy milling or electrochemical etching techniques. Such nanoscale silicon structures, whilst biodegradable in the human gastrointestinal tract, are shown to be remarkably stable in most foodstuffs and beverages. The potential for using silicon to improve the shelf life and bioavailability of specific nutrients in functional foods is highlighted. Published drug delivery data implies that the nanoentrapment of hydrophobic nutrients will significantly improve their dissolution kinetics, through a combined effect of nanostructuring and solid state modification. Nutrients loaded to date include vitamins, fish oils, lycopene and coenzyme Q10. In addition, there is growing published evidence that optimized release of orthosilicic acid, the biodegradation product of semiconducting silicon in the gut, offers beneficial effects with regard bone health. The utility of nanoscale silicon in the nutritional field shows early promise and is worthy of much further study.

  7. Probing silicon quantum dots by single-dot techniques

    Science.gov (United States)

    Sychugov, Ilya; Valenta, Jan; Linnros, Jan

    2017-02-01

    Silicon nanocrystals represent an important class of non-toxic, heavy-metal free quantum dots, where the high natural abundance of silicon is an additional advantage. Successful development in mass-fabrication, starting from porous silicon to recent advances in chemical and plasma synthesis, opens up new possibilities for applications in optoelectronics, bio-imaging, photovoltaics, and sensitizing areas. In this review basic physical properties of silicon nanocrystals revealed by photoluminescence spectroscopy, lifetime, intensity trace and electrical measurements on individual nanoparticles are summarized. The fabrication methods developed for accessing single Si nanocrystals are also reviewed. It is concluded that silicon nanocrystals share many of the properties of direct bandgap nanocrystals exhibiting sharp emission lines at low temperatures, on/off blinking, spectral diffusion etc. An analysis of reported results is provided in comparison with theory and with direct bandgap material quantum dots. In addition, the role of passivation and inherent interface/matrix defects is discussed.

  8. Every teacher an English teacher? Literacy strategy teaching and research in the content area of science education

    Science.gov (United States)

    Buckingham, Thomas

    Recent statements from teachers of English and literacy (NCTE, 2007) have voiced the failure of schools to help minority students and ELLs close the literacy achievement gap and the responsibility of all teachers to help with this endeavor. Central to this effort in secondary schools are the content area teachers, as their subjects constitute the bulk of school day instruction. While there have been small studies and field reports of what content teachers are or are not teaching in the way of literacy instruction (Fisher and Ivey, 2005; Verplaste, 1996, 1998; Vacca and Vacca 1989), researchers have not had success measuring the literacy practices of content area teachers in a broad-based study. This study focuses specifically on what many researchers in both the content literacy and ESL fields have emphasized for promoting literacy in the classroom---teaching metacognitive strategies. Twelve metacognitive functions derived from a literacy strategies handbook are employed as a means to ascertain strategy usage within the lessons whether specifically known content strategies are named or not. The initial analysis is performed on over 100 lesson plans hosted at four prominent university science education sites, all within a five year period (2003-7). In addition to the lesson plan analysis, a review of 100 articles taken from five on-line science education journals reveal what the science education field addresses this issue. Findings suggest that while 80% of science teachers include some type of strategic teaching and learning in their lessons, only about 20% of science teachers explicitly utilize strategies as listed in content literacy manuals and promoted by literacy and ESL experts. Rather, most science teachers implicitly include these strategies within their lessons and/or promote their own subject-specific strategies in content teaching. Analysis of science education research and publications shows that there is a focus on literacy and specifically strategic

  9. characterization of nanocrystalline silicon germanium film

    African Journals Online (AJOL)

    a

    The nanocrystalline silicon-germanium films (Si/Ge) and Si/Ge nanotubes have low ... Si/Ge nanostructures are considered as candidates with high potential for ... more attractive material than PS for both fundamental research and industrial ...

  10. The Tyrolean Alps LTSER platform – providing scientific insights for better management of protected areas. eco.mont (Journal on Protected Mountain Areas Research)|eco.mont Vol. 9 No. 1 9 1|

    OpenAIRE

    Kerle, Sarah; Tappeiner, Ulrike

    2017-01-01

    In a fast-changing world, Long-Term Socio-Ecological Research (LTSER) promises to provide new understanding of society-nature interactions. Management of protected areas (PAs) relies heavily on such scientific knowledge to address complex issues. Since large areas within the Tyrolean Alps are under protection, close collaboration between scientists working in LTSER within the Tyrolean Alps and the managers of PAs would be very beneficial for appropriate area management.

  11. The area-of-interest problem in eyetracking research: A noise-robust solution for face and sparse stimuli.

    Science.gov (United States)

    Hessels, Roy S; Kemner, Chantal; van den Boomen, Carlijn; Hooge, Ignace T C

    2016-12-01

    A problem in eyetracking research is choosing areas of interest (AOIs): Researchers in the same field often use widely varying AOIs for similar stimuli, making cross-study comparisons difficult or even impossible. Subjective choices while choosing AOIs cause differences in AOI shape, size, and location. On the other hand, not many guidelines for constructing AOIs, or comparisons between AOI-production methods, are available. In the present study, we addressed this gap by comparing AOI-production methods in face stimuli, using data collected with infants and adults (with autism spectrum disorder [ASD] and matched controls). Specifically, we report that the attention-attracting and attention-maintaining capacities of AOIs differ between AOI-production methods, and that this matters for statistical comparisons in one of three groups investigated (the ASD group). In addition, we investigated the relation between AOI size and an AOI's attention-attracting and attention-maintaining capacities, as well as the consequences for statistical analyses, and report that adopting large AOIs solves the problem of statistical differences between the AOI methods. Finally, we tested AOI-production methods for their robustness to noise, and report that large AOIs-using the Voronoi tessellation method or the limited-radius Voronoi tessellation method with large radii-are most robust to noise. We conclude that large AOIs are a noise-robust solution in face stimuli and, when implemented using the Voronoi method, are the most objective of the researcher-defined AOIs. Adopting Voronoi AOIs in face-scanning research should allow better between-group and cross-study comparisons.

  12. Game-Theory Based Research on Oil-Spill Prevention and Control Modes in Three Gorges Reservoir Area

    Science.gov (United States)

    Yin, Jie; Xiong, Ting

    2018-01-01

    Aiming at solving the existing oil pollution in the Three Gorges reservoir, this paper makes research on oil-spill prevention and control mode based on game theory. Regarding the built modes and comparative indicator system, overall efficiency indicator functions are used to compare general effect, overall cost, and overall efficiency, which concludes that the mode combining government and enterprise has the highest overall efficiency in preventing and controlling ship oil spills. The suggested mode together its correspondingly designed management system, has been applied to practice for a year in Three Gorges Reservoir Area and has made evident improvements to the existing oil pollution, meanwhile proved to be quite helpful to the pollution prevention and control in the lower reaches of Yangtze River.

  13. Principles, application areas and an example of risk assessment conducted at the Danish Institute for Food and Veterinary Research

    DEFF Research Database (Denmark)

    Greiner, Matthias; Paisley, Larry; Nørgaard, Julie Hostrup

    2004-01-01

    is responsible for the risk assessment component of the risk analysis process and provides advice and support for the risk management and risk communication component, which is generally under the auspices of the Danish Veterinary and Food Administration (DVFA). The paper presents guidelines for the conduct...... of risk assessments at the DFVF. Important elements of these guidelines are the independence between risk assessment and risk management, the commitment to science-based, transparent and fully documented procedures and adherence to a protocol that regulates the cooperation between DFVF and DVFA. Typical......The Department for Epidemiology and Risk Analysis at the Danish Institute for Food and Veterinary Research (DFVF) is concerned with risk analyses in the areas of food safety, zoo noses, antimicrobial resistance and OIE (World Organisation for Animal Health) list A and B diseases. The DFVF...

  14. A comparison of research into cachexia, wasting and related skeletal muscle syndromes in three chronic disease areas.

    Science.gov (United States)

    Stewart Coats, Andrew J; Shewan, Louise G

    2017-05-15

    We compared the frequency of cancer, heart and lung related cachexia and cachexia-related research articles in the specialist journal, Journal of Cachexia, Sarcopenia and Muscle (JCSM) to those seen in a leading European journal in each specialist area during 2015 and 2016 to assess whether work on cachexia and related fields is relatively over or under represented in each specialist area. In the dedicated journal, Journal of Cachexia, Sarcopenia and Muscle, there were 44 references related to cancer, 5 related to respiratory disease, 5 related to heart failure, and 21 related to more than one of these chronic diseases. Despite this cancer preponderance, in the European Journal of Cancer in the two publication years, there were only 5 relevant publications (0.67% of the journal output), compared to 16 (1.41%) in the European Respiratory Journal and 10 (2.19%) in the European Journal of Heart Failure. There is considerable under-representation of cancer cachexia-related papers in the major European Cancer journal despite a high proportion in the dedicated cachexia journal. The under-representation is even more marked when expressed as a percentage, 0.67%, compared to 1.41% and 2.19% of the lung and heart journals respectively. These results are consistent with a worrying lack of interest in, or publication of, cachexia and related syndromes research in the cancer literature in Europe compared to its importance as a clinical syndrome. Greater interest is shown in lung and cardiology journals. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  15. The Technological Mineralogical Research of Molybdenum in Skarn-type Ore of Huangshaping Polymetallic Mining Area, Hunan, China

    Science.gov (United States)

    Liu, W. H.; Pan, J. Y.

    2017-10-01

    Huangshaping is one of the most important polymetallic deposits in the south of Hunan Province. Through field investigation, chemical analysis, observation under the optical microscope, energy spectrum analysis of the SEM and X-ray diffraction, the author made a technological mineralogical research of molybdenum on skarn-type ore, and the result shows that the ore containing molybdenum is mainly on the contact of the granite porphyry and the impure limestone in the lower carboniferous Shidengzi group. Besides molybdenum, the ore minerals contain scheelite, native bismuth, bismuthinite, magnetite and so on; and the gangue minerals are mainly andradite, fluorite and wollastonite. Part of the molybdenum exists in the scheelite in form of isomorphism, and there is an obvious negative correlation between MoO3 and WO3. The molybdenite granularity is mainly located in the 0.04~ 0.08mm area, which accounts for 29.5% of the total and is the finely disseminated ore. For samples of 70%, 90%, and 100% with the particle size of more than 200 meshes, the maximum recovery of the molybdenite are 75.15%, 86.45% and 91.25% respectively. So there will be a better use of molybdenum if we properly improve the grinded particle size of the comprehensive samples. As part of the molybdenum is distributed in the scheelite lattice, the actual recovery rate in this area may decline compared with the ideal value.

  16. RESEARCH: Influence of Social, Biophysical, and Managerial Conditions on Tourism Experiences Within the Great Barrier Reef World Heritage Area.

    Science.gov (United States)

    Shafer; Inglis

    2000-07-01

    / Managing protected areas involves balancing the enjoyment of visitors with the protection of a variety of cultural and biophysical resources. Tourism pressures in the Great Barrier Reef World Heritage Area (GBRWHA) are creating concerns about how to strike this balance in a marine environment. Terrestrial-based research has led to conceptual planning and management frameworks that address issues of human use and resource protection. The limits of acceptable change (LAC) framework was used as a conceptual basis for a study of snorkeling at reef sites in the GBRWHA. The intent was to determine if different settings existed among tourism operators traveling to the reef and, if so, to identify specific conditions relating to those settings. Snorkelers (N = 1475) traveling with tourism operations of different sizes who traveled to different sites completed surveys. Results indicated that snorkelers who traveled with larger operations (more people and infrastructure) differed from those traveling with smaller operations (few people and little on-site infrastructure) on benefits received and in the way that specific conditions influenced their enjoyment. Benefits related to nature, escape, and family helped to define reef experiences. Conditions related to coral, fish, and operator staff had a positive influence on the enjoyment of most visitors but, number of people on the trip and site infrastructure may have the greatest potential as setting indicators. Data support the potential usefulness of visitor input in applying the LAC concept to a marine environment where tourism and recreational uses are rapidly changing.

  17. Research on the design of a buffer strip for nonpoint source pollution control in the Three Gorges Reservoir Area, China

    Science.gov (United States)

    Shan, N.; Ruan, X.

    2015-12-01

    Following the implementation of the Three Gorges Dam Project, nonpoint source (NPS) pollution has become a serious problem in the Three Gorges Reservoir (TGR). An urgent need exists to build buffer strips along the TGR to improve water quality. However, to design the optimal buffer strip for NPS pollution control is challenging because of spatial variations in topography, hydrology, slope and drainage patterns in the Three Gorges Reservoir Area (TGRA). This research focus on (1) plan the placement of buffer strip in the TGRA for water quality benefits using terrain analysis. (2) estimate suitable widths of buffer strip for different objectives of water quality protection to reflect regional variations in physical conditions. Terrain analysis can provide assessments for placement of conservation practices. There are some ineffective areas where the performance of conservation practices is minimal at watershed scale. The results showed that with increased conservation objectives, greater widths are required to ensure NPS pollutant removal and improvements in water quality. The widths of the modelling buffer vary significantly in spatial with variation in pollutant concentration, slope and soil conditions. It is necessary to install buffer strip along the tributary streams for NPS pollution control and water quality protection at the watershed scale.

  18. Micro-spectroscopy on silicon wafers and solar cells

    National Research Council Canada - National Science Library

    Gundel, Paul; Schubert, Martin C; Heinz, Friedemann D; Woehl, Robert; Benick, Jan; Giesecke, Johannes A; Suwito, Dominik; Warta, Wilhelm

    2011-01-01

    Micro-Raman (μRS) and micro-photoluminescence spectroscopy (μPLS) are demonstrated as valuable characterization techniques for fundamental research on silicon as well as for technological issues in the photovoltaic production...

  19. Determining the Scope of Collection Development and Research Assistance for Cross-Disciplinary Areas: A Case Study of Two Contrasting Areas, Nanotechnology and Transportation Engineering

    Science.gov (United States)

    Williamson, Jeanine M.; Han, Lee D.; Colon-Aguirre, Monica

    2009-01-01

    The study examined the extent of cross-disciplinarity in nanotechnology and transportation engineering research. Researchers in these two fields were determined from the web sites of the U.S. News and World Report top 100 schools in civil engineering and materials science. Web of Science searches for 2006 and 2007 articles were obtained and the…

  20. Nanoslits in silicon chips.

    Science.gov (United States)

    Aref, Thomas; Brenner, Matthew; Bezryadin, Alexey

    2009-01-28

    Potassium hydroxide (KOH) etching of a patterned [100] oriented silicon wafer produces V-shaped etch pits. We demonstrate that the remaining thickness of silicon at the tip of the etch pit can be reduced to approximately 5 microm using an appropriately sized etch mask and optical feedback. Starting from such an etched chip, we have developed two different routes for fabricating 100 nm scale slits that penetrate through the macroscopic silicon chip (the slits are approximately 850 microm wide at one face of the chip and gradually narrow to approximately 100-200 nm wide at the opposite face of the chip). In the first process, the etched chips are sonicated to break the thin silicon at the tip of the etch pit and then further KOH etched to form a narrow slit. In the second process, focused ion beam milling is used to etch through the thin silicon at the tip of the etch pit. The first method has the advantage that it uses only low-resolution technology while the second method offers more control over the length and width of the slit. Our slits can be used for preparing mechanically stable, transmission electron microscopy samples compatible with electrical transport measurements or as nanostencils for depositing nanowires seamlessly connected to their contact pads.