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Sample records for speed characterize pure

  1. Too Little, Too Late: Reduced Visual Span and Speed Characterize Pure Alexia

    Science.gov (United States)

    Habekost, Thomas; Leff, Alexander P.

    2009-01-01

    Whether normal word reading includes a stage of visual processing selectively dedicated to word or letter recognition is highly debated. Characterizing pure alexia, a seemingly selective disorder of reading, has been central to this debate. Two main theories claim either that 1) Pure alexia is caused by damage to a reading specific brain region in the left fusiform gyrus or 2) Pure alexia results from a general visual impairment that may particularly affect simultaneous processing of multiple items. We tested these competing theories in 4 patients with pure alexia using sensitive psychophysical measures and mathematical modeling. Recognition of single letters and digits in the central visual field was impaired in all patients. Visual apprehension span was also reduced for both letters and digits in all patients. The only cortical region lesioned across all 4 patients was the left fusiform gyrus, indicating that this region subserves a function broader than letter or word identification. We suggest that a seemingly pure disorder of reading can arise due to a general reduction of visual speed and span, and explain why this has a disproportionate impact on word reading while recognition of other visual stimuli are less obviously affected. PMID:19366870

  2. Thermomechanical characterization of pure polycrystalline tantalum

    International Nuclear Information System (INIS)

    Rittel, D.; Bhattacharyya, A.; Poon, B.; Zhao, J.; Ravichandran, G.

    2007-01-01

    The thermomechanical behavior of pure polycrystalline tantalum has been characterized over a wide range of strain rates, using the recently developed shear compression specimen [D. Rittel, S. Lee, G. Ravichandran, Experimental Mechanics 42 (2002) 58-64]. Dynamic experiments were carried out using a split Hopkinson pressure bar, and the specimen's temperature was monitored throughout the tests using an infrared radiometer. The results of the mechanical tests confirm previous results on pure Ta. Specifically, in addition to its significant strain rate sensitivity, it was observed that pure Ta exhibits very little strain hardening at high strain rates. The measured temperature rise in the specimen's gauge was compared to theoretical predictions which assume a total conversion of the mechanical energy into heat (β = 1) [G.I. Taylor, H. Quinney, Proceedings of the Royal Society of London, vol. A, 1934, pp. 307-326], and an excellent agreement was obtained. This result confirms the previous result of Kapoor and Nemat-Nasser [R. Kapoor, S. Nemat-Nasser, Mech. Mater. 27 (1998) 1-12], while a different experimental approach was adopted here. The assumption that β = 1 is found to be justified in this specific case by the lack of dynamic strain hardening of pure Ta. However, this assumption should be limited to non-hardening materials, to reflect the fact that strain hardening implies that part of the mechanical energy is stored into the material's microstructure

  3. High Speed On-Wafer Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At the High Speed On-Wafer Characterization Laboratory, researchers characterize and model devices operating at terahertz (THz) and millimeter-wave frequencies. The...

  4. Growth and characterization of gel grown pure and mixed iron ...

    Indian Academy of Sciences (India)

    Unknown

    is to grow pure and mixed iron (II)–manganese levo-tartrate crystals by the single diffusion gel growth technique and characterize them by several methods. 2. ... also attracted several researchers to grow different crystals for various ...

  5. Characterization of pure and copper-doped iron tartrate crystals

    Indian Academy of Sciences (India)

    Single crystal growth of pure and copper-doped iron tartrate crystals bearing composition Cu Fe(1−) C4H4O6 · H2O, where = 0, 0.07, 0.06, 0.05, 0.04, 0.03, is achieved using gel technique. The elemental analysis has been done using energy-dispersive X-ray analysis (EDAX) spectrum. The characterization studies ...

  6. Thermal characterization of commercially pure titanium for dental applications

    Directory of Open Access Journals (Sweden)

    Enori Gemelli

    2007-09-01

    Full Text Available Thermal characterization of commercially pure titanium was carried out in dry air to investigate the oxidation kinetics, the oxide structures and their properties. Oxidation kinetics were performed by thermogravimetry in isothermal conditions between 300 and 750 °C for 48 hours and the oxide structures were studied by differential thermal analyses and X ray diffraction between room temperature and 1000 °C. The oxidation kinetic increases with temperature and is very fast in the initial period of oxidation, decreasing rapidly with time, especially up to 600 °C. Kinetic laws varied between the inverse logarithmic for the lower temperatures (300 and 400 °C and the parabolic for the higher temperatures (650, 700 and 750 °C. Evidences from X ray diffraction and differential thermal analyses showed that crystallization of the passive oxide film, formed at room temperature, into anatase occurs at about 276 °C. The crystallized oxide structure is composed of anatase between 276 and 457 °C, anatase and rutile sublayers between 457 and 718 °C, and a pure layer of rutile after 718 °C. Rockwell-C adhesion tests reveled that the oxide films formed up to 600 °C have a good adhesion. Vickers indentations on the oxidized surfaces showed that the hardness of the oxide film, measured at 600 and 650 °C, is approximately 9500 MPa. At these temperatures the surface roughness varied between 0.90 and 1.30 mm.

  7. Characterizing commercial pureed foods: sensory, nutritional, and textural analysis.

    Science.gov (United States)

    Ettinger, Laurel; Keller, Heather H; Duizer, Lisa M

    2014-01-01

    Dysphagia (swallowing impairment) is a common consequence of stroke and degenerative diseases such as Parkinson's and Alzheimer's. Limited research is available on pureed foods, specifically the qualities of commercial products. Because research has linked pureed foods, specifically in-house pureed products, to malnutrition due to inferior sensory and nutritional qualities, commercial purees also need to be investigated. Proprietary research on sensory attributes of commercial foods is available; however direct comparisons of commercial pureed foods have never been reported. Descriptive sensory analysis as well as nutritional and texture analysis of commercially pureed prepared products was performed using a trained descriptive analysis panel. The pureed foods tested included four brands of carrots, of turkey, and two of bread. Each commercial puree was analyzed for fat (Soxhlet), protein (Dumas), carbohydrate (proximate analysis), fiber (total fiber), and sodium content (Quantab titrator strips). The purees were also texturally compared with a line spread test and a back extrusion test. Differences were found in the purees for sensory attributes as well as nutritional and textural properties. Findings suggest that implementation of standards is required to reduce variability between products, specifically regarding the textural components of the products. This would ensure all commercial products available in Canada meet standards established as being considered safe for swallowing.

  8. Parameter design and performance analysis of shift actuator for a two-speed automatic mechanical transmission for pure electric vehicles

    Directory of Open Access Journals (Sweden)

    Jianjun Hu

    2016-08-01

    Full Text Available Recent developments of pure electric vehicles have shown that pure electric vehicles equipped with two-speed or multi-speed gearbox possess higher energy efficiency by ensuring the drive motor operates at its peak performance range. This article presents the design, analysis, and control of a two-speed automatic mechanical transmission for pure electric vehicles. The shift actuator is based on a motor-controlled camshaft where a special geometric groove is machined, and the camshaft realizes the axial positions of the synchronizer sleeve for gear engaging, disengaging, and speed control of the drive motor. Based on the force analysis of shift process, the parameters of shift actuator and shift motor are designed. The drive motor’s torque control strategy before shifting, speed governing control strategy before engaging, shift actuator’s control strategy during gear engaging, and drive motor’s torque recovery strategy after shift process are proposed and implemented with a prototype. To validate the performance of the two-speed gearbox, a test bed was developed based on dSPACE that emulates various operation conditions. The experimental results indicate that the shift process with the proposed shift actuator and control strategy could be accomplished within 1 s under various operation conditions, with shift smoothness up to passenger car standard.

  9. Wear behaviors of pure aluminum and extruded aluminum alloy (AA2024-T4) under variable vertical loads and linear speeds

    Science.gov (United States)

    Jung, Jeki; Oak, Jeong-Jung; Kim, Yong-Hwan; Cho, Yi Je; Park, Yong Ho

    2017-11-01

    The aim of this study was to investigate the transition of wear behavior for pure aluminum and extruded aluminum alloy 2024-T4 (AA2024-T4). The wear test was carried using a ball-on-disc wear testing machine at various vertical loads and linear speeds. The transition of wear behaviors was analyzed based on the microstructure, wear tracks, wear cross-section, and wear debris. The critical wear rates for each material are occurred at lower linear speed for each vertical load. The transition of wear behavior was observed in which abrasion wears with the generation of an oxide layer, fracture of oxide layer, adhesion wear, severe adhesion wear, and the generation of seizure occurred in sequence. In case of the pure aluminum, the change of wear debris occurred in the order of blocky, flake, and needle-like debris. Cutting chip, flake-like, and coarse flake-like debris was occurred in sequence for the extruded AA2024-T4. The transition in the wear behavior of extruded AA2024-T4 occurred slower than in pure aluminum.

  10. Characterizing speed-independence of high-level designs

    DEFF Research Database (Denmark)

    Kishinevsky, Michael; Staunstrup, Jørgen

    1994-01-01

    This paper characterizes the speed-independence of high-level designs. The characterization is a condition on the design description ensuring that the behavior of the design is independent of the speeds of its components. The behavior of a circuit is modeled as a transition system, that allows data...... types, and internal as well as external non-determinism. This makes it possible to verify the speed-independence of a design without providing an explicit realization of the environment. The verification can be done mechanically. A number of experimental designs have been verified including a speed-independent...

  11. Optical characterization of phase transitions in pure polymers and blends

    Energy Technology Data Exchange (ETDEWEB)

    Mannella, Gianluca A.; Brucato, Valerio; La Carrubba, Vincenzo, E-mail: vincenzo.lacarrubba@unipa.it [Department of Civil, Environmental, Aerospace and Materials Engineering (DICAM), University of Palermo, Viale delle Scienze, Ed. 8, 90128 Palermo (Italy)

    2015-12-17

    To study the optical properties of polymeric samples, an experimental apparatus was designed on purpose and set up. The sample is a thin film enclosed between two glass slides and a PTFE frame, with a very thin thermocouple placed on sample for direct temperature measurement. This sample holder was placed between two aluminum slabs, equipped with a narrow slit for optical measurements and with electrical resistances for temperature control. Sample was enlightened by a laser diode, whereas transmitted light was detected with a photodiode. Measurements were carried out on polyethylene-terephtalate (PET) and two different polyamides, tested as pure polymers and blends. The thermal history imposed to the sample consisted in a rapid heating from ambient temperature to a certain temperature below the melting point, a stabilization period, and then a heating at constant rate. After a second stabilization period, the sample was cooled. The data obtained were compared with DSC measurements performed with the same thermal history. In correspondence with transitions detected via DSC (e.g. melting, crystallization and cold crystallization), the optical signal showed a steep variation. In particular, crystallization resulted in a rapid decrease of transmitted light, whereas melting gave up an increase of light transmitted by the sample. Further variations in transmitted light were recorded for blends, after melting: those results may be related to other phase transitions, e.g. liquid-liquid phase separation. All things considered, the apparatus can be used to get reliable data on phase transitions in polymeric systems.

  12. Optical characterization of phase transitions in pure polymers and blends

    International Nuclear Information System (INIS)

    Mannella, Gianluca A.; Brucato, Valerio; La Carrubba, Vincenzo

    2015-01-01

    To study the optical properties of polymeric samples, an experimental apparatus was designed on purpose and set up. The sample is a thin film enclosed between two glass slides and a PTFE frame, with a very thin thermocouple placed on sample for direct temperature measurement. This sample holder was placed between two aluminum slabs, equipped with a narrow slit for optical measurements and with electrical resistances for temperature control. Sample was enlightened by a laser diode, whereas transmitted light was detected with a photodiode. Measurements were carried out on polyethylene-terephtalate (PET) and two different polyamides, tested as pure polymers and blends. The thermal history imposed to the sample consisted in a rapid heating from ambient temperature to a certain temperature below the melting point, a stabilization period, and then a heating at constant rate. After a second stabilization period, the sample was cooled. The data obtained were compared with DSC measurements performed with the same thermal history. In correspondence with transitions detected via DSC (e.g. melting, crystallization and cold crystallization), the optical signal showed a steep variation. In particular, crystallization resulted in a rapid decrease of transmitted light, whereas melting gave up an increase of light transmitted by the sample. Further variations in transmitted light were recorded for blends, after melting: those results may be related to other phase transitions, e.g. liquid-liquid phase separation. All things considered, the apparatus can be used to get reliable data on phase transitions in polymeric systems

  13. Quantitative characterization of microstructure of pure copper processed by ECAP

    Czech Academy of Sciences Publication Activity Database

    Šedivý, O.; Beneš, V.; Ponížil, P.; Král, Petr; Sklenička, Václav

    2013-01-01

    Roč. 32, č. 2 (2013), s. 65-75 ISSN 1580-3139 Institutional support: RVO:68081723 Keywords : electron backscatter diffraction * ultrafine-grained metals * microstructure * microstructure characterization * grain boundaries Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.697, year: 2013

  14. Monitoring ice nucleation in pure and salty water via high-speed imaging and computer simulations

    Czech Academy of Sciences Publication Activity Database

    Bauerecker, S.; Ulbig, P.; Buch, V.; Vrbka, Luboš; Jungwirth, Pavel

    2008-01-01

    Roč. 112, č. 20 (2008), s. 7631-7636 ISSN 1932-7447 R&D Projects: GA MŠk LC512; GA ČR(CZ) GD203/05/H001 Grant - others:DFG(DE) 529278 Institutional research plan: CEZ:AV0Z40550506 Keywords : ice freezing * high speed imaging * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.396, year: 2008

  15. Effect of Laser Power and Scan Speed on Melt Pool Characteristics of Commercially Pure Titanium (CP-Ti)

    Science.gov (United States)

    Kusuma, Chandrakanth; Ahmed, Sazzad H.; Mian, Ahsan; Srinivasan, Raghavan

    2017-07-01

    Selective laser melting (SLM) is an additive manufacturing technique that creates complex parts by selectively melting metal powder layer-by-layer using a laser. In SLM, the process parameters decide the quality of the fabricated component. In this study, single beads of commercially pure titanium (CP-Ti) were melted on a substrate of the same material using an in-house built SLM machine. Multiple combinations of laser power and scan speed were used for single bead fabrication, while the laser beam diameter and powder layer thickness were kept constant. This experimental study investigated the influence of laser power, scan speed, and laser energy density on the melt pool formation, surface morphology, geometry (width and height), and hardness of solidified beads. In addition, the observed unfavorable effect such as inconsistency in melt pool width formation is discussed. The results show that the quality, geometry, and hardness of solidified melt pool are significantly affected by laser power, scanning speed, and laser energy density.

  16. Geometric characterization of separability and entanglement in pure Gaussian states by single-mode unitary operations

    Science.gov (United States)

    Adesso, Gerardo; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-10-01

    We present a geometric approach to the characterization of separability and entanglement in pure Gaussian states of an arbitrary number of modes. The analysis is performed adapting to continuous variables a formalism based on single subsystem unitary transformations that has been recently introduced to characterize separability and entanglement in pure states of qubits and qutrits [S. M. Giampaolo and F. Illuminati, Phys. Rev. A 76, 042301 (2007)]. In analogy with the finite-dimensional case, we demonstrate that the 1×M bipartite entanglement of a multimode pure Gaussian state can be quantified by the minimum squared Euclidean distance between the state itself and the set of states obtained by transforming it via suitable local symplectic (unitary) operations. This minimum distance, corresponding to a , uniquely determined, extremal local operation, defines an entanglement monotone equivalent to the entropy of entanglement, and amenable to direct experimental measurement with linear optical schemes.

  17. Geometric characterization of separability and entanglement in pure Gaussian states by single-mode unitary operations

    International Nuclear Information System (INIS)

    Adesso, Gerardo; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-01-01

    We present a geometric approach to the characterization of separability and entanglement in pure Gaussian states of an arbitrary number of modes. The analysis is performed adapting to continuous variables a formalism based on single subsystem unitary transformations that has been recently introduced to characterize separability and entanglement in pure states of qubits and qutrits [S. M. Giampaolo and F. Illuminati, Phys. Rev. A 76, 042301 (2007)]. In analogy with the finite-dimensional case, we demonstrate that the 1xM bipartite entanglement of a multimode pure Gaussian state can be quantified by the minimum squared Euclidean distance between the state itself and the set of states obtained by transforming it via suitable local symplectic (unitary) operations. This minimum distance, corresponding to a, uniquely determined, extremal local operation, defines an entanglement monotone equivalent to the entropy of entanglement, and amenable to direct experimental measurement with linear optical schemes

  18. Optical characterization of pure vegetable oils and their biodiesels using Raman spectroscopy

    Science.gov (United States)

    Firdous, S.; Anwar, S.; Waheed, A.; Maraj, M.

    2016-04-01

    Great concern regarding energy resources and environmental polution has increased interest in the study of alternative sources of energy. Biodiesels as an alternative fuel provide a suitable diesel oil substitute for internal combustion engines. The Raman spectra of pure biodiesels of soybean oil, olive oil, coconut oil, animal fats, and petroleum diesel are optically characterized for quality and biofuel as an alternative fuel. The most significant spectral differences are observed in the frequency range around 1457 cm-1 for pure petroleum diesel, 1427 for fats biodiesel, 1670 cm-1 for pure soybean oil, 1461 cm-1 for soybean oil based biodiesel, 1670 cm-1 for pure olive oil, 1666 cm-1 for olive oil based biodiesel, 1461 cm-1 for pure coconut oil, and 1460 cm-1 for coconut oil based biodiesel, which is used for the analysis of the phase composition of oils. A diode pump solid-state laser with a 532 nm wavelength is used as an illuminating light. It is demonstrated that the peak positions and relative intensities of the vibrations of the oils can be used to identify the biodiesel quality for being used as biofuel.

  19. Optical characterization of pure vegetable oils and their biodiesels using Raman spectroscopy

    International Nuclear Information System (INIS)

    Firdous, S; Anwar, S; Waheed, A; Maraj, M

    2016-01-01

    Great concern regarding energy resources and environmental polution has increased interest in the study of alternative sources of energy. Biodiesels as an alternative fuel provide a suitable diesel oil substitute for internal combustion engines. The Raman spectra of pure biodiesels of soybean oil, olive oil, coconut oil, animal fats, and petroleum diesel are optically characterized for quality and biofuel as an alternative fuel. The most significant spectral differences are observed in the frequency range around 1457 cm −1 for pure petroleum diesel, 1427 for fats biodiesel, 1670 cm −1 for pure soybean oil, 1461 cm −1 for soybean oil based biodiesel, 1670 cm −1 for pure olive oil, 1666 cm −1 for olive oil based biodiesel, 1461 cm −1 for pure coconut oil, and 1460 cm −1 for coconut oil based biodiesel, which is used for the analysis of the phase composition of oils. A diode pump solid-state laser with a 532 nm wavelength is used as an illuminating light. It is demonstrated that the peak positions and relative intensities of the vibrations of the oils can be used to identify the biodiesel quality for being used as biofuel. (paper)

  20. Characterizing the speed and paths of shared bicycles in Lyon

    OpenAIRE

    Jensen , Pablo; Rouquier , Jean-Baptiste; Ovtracht , Nicolas; Robardet , Céline

    2010-01-01

    Thanks to numerical data gathered by Lyon's shared bicycling system V\\'elo'v, we are able to analyze 11.6 millions bicycle trips, leading to the first robust characterization of urban bikers' behaviors. We show that bicycles outstrip cars in downtown Lyon, by combining high speed and short paths.These data also allows us to calculate V\\'elo'v fluxes on all streets, pointing to interesting locations for bike paths.

  1. Synthesis and characterization of ceramic powders of pure and doped with trivalent erbium barium tungstate

    International Nuclear Information System (INIS)

    Sousa, R.B. de; Nascimento, V.A. do; Matos, J. M.E. de; Santos, M.R.M.C.

    2014-01-01

    This research proposes the synthesis and characterization of pure and doped with Er"3"+ (1 and 2 %) barium tungstate powders prepared by the coprecipitation method. In order to characterize the obtained powders were used X-Ray Diffractometry, Raman Spectroscopy and Fourier Transform Infrared Spectroscopy. According to the standard XRD spectra, the crystals exhibited the presence of tetragonal scheelite structure without the presence of secondary phases. Raman spectra showed the presence of eleven vibrational modes and two modes were observed in the infrared spectra. The synthesized oxides showed good crystallinity and structurally ordered at short and long-range. (author)

  2. Speed-dependent Voigt lineshape parameter database from dual frequency comb measurements up to 1305 K. Part I: Pure H2O absorption, 6801-7188 cm-1

    Science.gov (United States)

    Schroeder, Paul J.; Cich, Matthew J.; Yang, Jinyu; Giorgetta, Fabrizio R.; Swann, William C.; Coddington, Ian; Newbury, Nathan R.; Drouin, Brian J.; Rieker, Gregory B.

    2018-05-01

    We measure speed-dependent Voigt lineshape parameters with temperature-dependence exponents for several hundred spectroscopic features of pure water spanning 6801-7188 cm-1. The parameters are extracted from broad bandwidth, high-resolution dual frequency comb absorption spectra with multispectrum fitting techniques. The data encompass 25 spectra ranging from 296 K to 1305 K and 1 to 17 Torr of pure water vapor. We present the extracted parameters, compare them to published data, and present speed-dependence, self-shift, and self-broadening temperature-dependent parameters for the first time. Lineshape data is extracted using a quadratic speed-dependent Voigt profile and a single self-broadening power law temperature-dependence exponent over the entire temperature range. The results represent an important step toward a new high-temperature database using advanced lineshape profiles.

  3. Espresso beverages of pure origin coffee: mineral characterization, contribution for mineral intake and geographical discrimination.

    Science.gov (United States)

    Oliveira, Marta; Ramos, Sandra; Delerue-Matos, Cristina; Morais, Simone

    2015-06-15

    Espresso coffee beverages prepared from pure origin roasted ground coffees from the major world growing regions (Brazil, Ethiopia, Colombia, India, Mexico, Honduras, Guatemala, Papua New Guinea, Kenya, Cuba, Timor, Mussulo and China) were characterized and compared in terms of their mineral content. Regular consumption of one cup of espresso contributes to a daily mineral intake varying from 0.002% (sodium; Central America) to 8.73% (potassium; Asia). The mineral profiles of the espresso beverages revealed significant inter- and intra-continental differences. South American pure origin coffees are on average richer in the analyzed elements except for calcium, while samples from Central America have generally lower mineral amounts (except for manganese). Manganese displayed significant differences (pworld coffee producers were achieved by applying canonical discriminant analysis. Manganese and calcium were found to be the best chemical descriptors for origin. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Structural characterization of pure and doped calcium phosphate bioceramics prepared by simple solid state method

    International Nuclear Information System (INIS)

    Ahmed, S.; Kabir, H.; Nigar, F.

    2011-01-01

    Calcium Phosphate based bioceramic materials, in pure and doped forms have been successfully synthesized from egg shells by using solid-state method for the first time. Considering the diverse role of zinc and fluoride in biological functions, these two ions were chosen to develop the substituted bioceramic materials. Structural characterizations of these developed bioceramics were performed by using FTIR, XRD, SEM and EDS techniques. The results revealed that the fluoride doped apatite was formed in single phase containing hydroxyapatite while pure and Zinc doped apatites contained -TCP with hydroxyapatite. Experimental results and the crystallographic parameters matched well with the literature values indicating that the present experimental protocol favoured the formation of the desired bioceramics. However, to synthesize the (Ca (PO)) based bioceramic materials, such a simple solid-state approach would obviously be very helpful, not only in making the process economically feasible, but also in creating an effective material recycling technology for waste-management. (author)

  5. Effects of alloying element on weld characterization of laser-arc hybrid welding of pure copper

    Science.gov (United States)

    Hao, Kangda; Gong, Mengcheng; Xie, Yong; Gao, Ming; Zeng, Xiaoyan

    2018-06-01

    Effects of alloying elements of Si and Sn on weld characterizations of laser-arc hybrid welded pure copper (Cu) with thickness of 2 mm was studied in detail by using different wires. The weld microstructure was analyzed, and the mechanical properties (micro-hardness and tensile property), conductivity and corrosion resistance were tested. The results showed that the alloying elements benefit the growth of column grains within weld fusion zone (FZ), increase the ultimate tensile strength (UTS) of the FZ and weld corrosion resistance, and decrease weld conductivity. The mechanisms were discussed according to the results.

  6. Speed

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Speed. The rate of information transferred per second is the speed of the information. Measured in bits per second. Need for speed on the net: You-Tube phenomenon; IPTV; 3D Video telephony. Online gaming; HDTV.

  7. Synthesis and Characterization of Pure Copper Nanostructures Using Wood Inherent Architecture as a Natural Template

    Science.gov (United States)

    Dong, Youming; Wang, Kaili; Tan, Yi; Wang, Qingchun; Li, Jianzhang; Mark, Hughes; Zhang, Shifeng

    2018-04-01

    The inherent sophisticated structure of wood inspires researchers to use it as a natural template for synthesizing functional nanoparticles. In this study, pure copper nanoparticles were synthesized using poplar wood as a natural inexpensive and renewable template. The crystal structure and morphologies of the copper nanoparticles were characterized by X-ray diffraction and field emission scanning electron microscopy. The optical properties, antibacterial properties, and stability of the hybrid wood materials were also tested. Due to the hierarchical and anisotropic structure and electron-rich components of wood, pure copper nanoparticles with high stability were synthesized with fcc structure and uniform sizes and then assembled into corncob-like copper deposits along the wood cell lumina. The products of nanoparticles depended strongly on the initial OH- concentration. With an increase in OH- concentration, Cu2O gradually decreased and Cu remained. Due to the restrictions inherent in wood structure, the derived Cu nanoparticles showed similar grain size in spite of increased Cu2+ concentration. This combination of Cu nanostructures and wood exhibited remarkable optical and antibacterial properties.

  8. Concurrent Flame Growth, Spread and Extinction over Composite Fabric Samples in Low Speed Purely Forced Flow in Microgravity

    Science.gov (United States)

    Zhao, Xiaoyang; T'ien, James S.; Ferkul, Paul V.; Olson, Sandra L.

    2015-01-01

    As a part of the NASA BASS and BASS-II experimental projects aboard the International Space Station, flame growth, spread and extinction over a composite cotton-fiberglass fabric blend (referred to as the SIBAL fabric) were studied in low-speed concurrent forced flows. The tests were conducted in a small flow duct within the Microgravity Science Glovebox. The fuel samples measured 1.2 and 2.2 cm wide and 10 cm long. Ambient oxygen was varied from 21% down to 16% and flow speed from 40 cm/s down to 1 cm/s. A small flame resulted at low flow, enabling us to observe the entire history of flame development including ignition, flame growth, steady spread (in some cases) and decay at the end of the sample. In addition, by decreasing flow velocity during some of the tests, low-speed flame quenching extinction limits were found as a function of oxygen percentage. The quenching speeds were found to be between 1 and 5 cm/s with higher speed in lower oxygen atmosphere. The shape of the quenching boundary supports the prediction by earlier theoretical models. These long duration microgravity experiments provide a rare opportunity for solid fuel combustion since microgravity time in ground-based facilities is generally not sufficient. This is the first time that a low-speed quenching boundary in concurrent spread is determined in a clean and unambiguous manner.

  9. Preparation and characterization of very pure zirconium tetrafluoride. Application to fluorinated glass

    International Nuclear Information System (INIS)

    Bridenne, M.

    1986-12-01

    The synthesis of anhydrous and very pure zirconium tetrafluoride from zirconium tetraborohydride is studied. Zr F 4 is used for fabrication of fluorozirconate glass. Zr (BH 4 ) 4 is purified by sublimation. Two fluorinating agents F 2 and anhydrous HF are used for fluorination. The apparatus is made of fluorinated polymers and a Kel-F prototype reactor was realized. 20 g of Zr F 4 are obtained in 44 hrs with a yield of 88 %. Purity is characterized by chemical analysis (atomique absorption spectroscopy and spark mass spectroscopy) and absorption of an optical fiber made of zirconium tetrafluoride. Cr, Ni, Co and Cu content is lower than 0.1 ppm. Possibility of pilot scale production is discussed [fr

  10. Synthesis and characterization of pure and Tb/Cu doped Alq3 nanostructures

    International Nuclear Information System (INIS)

    Salah, Numan; Habib, Sami S.; Khan, Zishan H.; Alharbi, Najlaa D.

    2013-01-01

    Tris (8-hydroxyquinoline) aluminum (Alq 3 ) is an organic semiconductor molecule, widely used in optoelectronic devices. In this work we report on fabricating different nanostructures of Alq 3 and characterize them using different techniques. Nanostructured films of Alq 3 were grown using the physical vapor condensation and thermal-vapor transport methods. The as synthesized films were characterized by X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and absorption spectra. Nanoparticles and nanorods/nanowires are observed in the synthesized films. Tb and Cu doped Alq 3 films were also produced and studied for their photoluminescence (PL) properties. When the original powder sample of Alq 3 was excited by 378 nm, one broad PL emission band is observed at around 515 nm. The pure nanoparticles film shows similar band with a drastic increase in the intensity by a factor of 2. This has been attributed to the large specific surface area, which might has increased the absorption and then the quantum yields. The Tb and Cu doped films show also similar band with a slight shift in the peak position to the blue region, but with further enhancement in the peak intensity, particularly that of Cu. The PL intensity of Cu doped sample is around 1.5 times stronger than that of the pure Alq 3 nanoparticles. This remarkable result on obtaining highly luminescent nanomaterial based on Cu doped Alq 3 nanoparticles film might be useful for future organic light emitting diode display devices. -- Highlights: • Films of Alq 3 nanostructures were grown using different methods. • The PL intensity of Alq 3 in its nanostructure form is enhanced by a factor of 2. • This enhancement is attributed to the large specific surface area of the nanostructures. • Films of Alq 3 nanoparticles doped with Tb and Cu showed further PL enhancement. • The Tb and Cu ions could contribute to the PL intensity of the green band of Alq3

  11. Extraction and characterization of bound extracellular polymeric substances from cultured pure cyanobacterium (Microcystis wesenbergii).

    Science.gov (United States)

    Liu, Lizhen; Qin, Boqiang; Zhang, Yunlin; Zhu, Guangwei; Gao, Guang; Huang, Qi; Yao, Xin

    2014-08-01

    Preliminary characterization of bound extracellular polymeric substances (bEPS) of cyanobacteria is crucial to obtain a better understanding of the formation mechanism of cyanobacterial bloom. However, the characterization of bEPS can be affected by extraction methods. Five sets (including the control) of bEPS from Microcystis extracted by different methods were characterized using three-dimensional excitation and emission matrix (3DEEM) fluorescence spectroscopy combined chemical spectrophotometry; and the characterization results of bEPS samples were further compared. The agents used for extraction were NaOH, pure water and phosphate buffered saline (PBS) containing cationic exchange resins, and hot water. Extraction methods affected the fluorescence signals and intensities in the bEPS. Five fluorescence peaks were observed in the excitation and emission matrix fluorescence spectra of bEPS samples. Two peaks (peaks T₁ and T₂) present in all extractions were identified as protein-like fluorophores, two (peaks A and C) as humic-like fluorophores, and one (peak E) as a fulvic-like substance. Among these substances, the humic-like and fulvic-like fluorescences were only seen in the bEPS extracted with hot water. Also, NaOH solution extraction could result in strong fluorescence intensities compared to the other extraction methods. It was suggested that NaOH at pH10.0 was the most appropriate method to extract bEPS from Microcystis. In addition, dialysis could affect the yields and characteristics of extracted bEPS during the determination process. These results will help us to explore the issues of cyanobacterial blooms. Copyright © 2014. Published by Elsevier B.V.

  12. Analytical characterization of pure and blended watermelon (citrullus lanatus) oil: impact of blending on oxidative stability

    International Nuclear Information System (INIS)

    Azeem, M.W.; Nadeem, M.

    2015-01-01

    Analytical characterization of pure, blended watermelon (Citrulluslanatus) oil and impact of blending on oxidative stability was investigated. Watermelon oil was added with mango (Mangiferaindica L.) kernel oil at four different concentrations 5, 10, 15 and 20% (B 1, B2, B3 and B4) and referenced with a control (100% watermelon oil). All the blends were stored in transparent PET bottles at ambient temperature (25-28 degree C) for 3 months; storage stability was assessed at the interval of 1 month. Free fatty acid, unsaponifiable matter, saponification value, refractive index and iodine value of watermelon seed oil and mango kernel oil was 1.38%, 0.34%; 0.71%, 1.68%; 198, 193; 1.468, 1.457; 107.51, 54.62, respectively. The tocopherol content of watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 127.49, 205.44, 135.24, 144.52, 156.81 and 169.34 mg/kg. delta tocopherol in watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 55.26, 34.81, 53.64, 51.27, 50.14 and 48.23 mg/kg. Concentration of linoleic acid decreased from 50.78% to 30.17% when 40% mango kernel oil was added to watermelon oil. Oleic acid increased from 22.89% in watermelon oil to 25.19%, 28.84% and 30.64% in B1, B2, B3 and B4. The increase in peroxide value of watermelon oil, B1, B2, B3 and B4 was 10.07, 9.56, 7.62, 5.17 and 2.87 (meqO/sub 2//kg) in a time dependent manner. Induction period of pure watermelon oil was less than mango kernel oil and blends. These results suggest that chemical characteristics and oxidative stability of pure watermelon oil can be improved by blending with mango kernel oil. (author)

  13. Analytical Characterization of Pure and Blended Watermelon (Citrullus lanatus oil: Impact of Blending on Oxidative Stability

    Directory of Open Access Journals (Sweden)

    Muhammad Waqar Azeem

    2015-06-01

    Full Text Available Analytical characterization of pure, blended watermelon (Citrulluslanatus oil and impact of blending on oxidative stability was investigated. Watermelon oil was added with mango (Mangiferaindica L. kernel oil at four different concentrations 5, 10, 15 and 20% (B1, B2, B3 and B4 and referenced with a control (100% watermelon oil. All the blends were stored in transparent PET bottles at ambient temperature (25-28oC for 3 months; storage stability was assessed at the interval of 1 month. Free fatty acid, unsaponifiable matter, saponification value, refractive index and iodine value of watermelon seed oil and mango kernel oil was 1.38%, 0.34%; 0.71%, 1.68%; 198, 193; 1.468, 1.457; 107.51, 54.62, respectively. The α tocopherol content of watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 127.49, 205.44, 135.24, 144.52, 156.81 and 169.34 mg/kg. δ tocopherol in watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 55.26, 34.81, 53.64, 51.27, 50.14 and 48.23 mg/kg. Concentration of linoleic acid decreased from 50.78% to 30.17% when 40% mango kernel oil was added to watermelon oil. Oleic acid increased from 22.89% in watermelon oil to 25.19%, 28.84% and 30.64% in B1, B2, B3 and B4. The increase in peroxide value of watermelon oil, B1, B2, B3 and B4 was 10.07, 9.56, 7.62, 5.17 and 2.87 (meqO2/kg in a time dependent manner. Induction period of pure watermelon oil was less than mango kernel oil and blends. These results suggest that chemical characteristics and oxidative stability of pure watermelon oil can be improved by blending with mango kernel oil.

  14. Preparation and initial characterization of fluidized bed steam reforming pure-phase standards

    Energy Technology Data Exchange (ETDEWEB)

    Missimer, D. M.; Rutherford, R. L.

    2013-03-21

    Hanford is investigating the Fluidized Bed Steam Reforming (FBSR) process for their Low Activity Waste. The FBSR process offers a low-temperature continuous method by which liquid waste can be processed with the addition of clay into a sodium aluminosilicate (NAS) waste form. The NAS waste form is mainly comprised of nepheline (NaAlSiO{sub 4}), sodalite (Na{sub 8}[AlSiO{sub 4}]{sub 6}Cl{sub 2}), and nosean (Na{sub 8}[AlSiO{sub 4}]{sub 6}SO{sub 4}). Anions such as perrhenate (ReO{sub 4}{sup -}), pertechnetate (TcO{sub 4}{sup -}), and iodine (I{sup -}) are expected to replace sulfate in the nosean structure and/or chloride in the sodalite mineral structure (atomically bonded inside the aluminosilicate cages that these mineral structures possess). In the FBSR waste form, each of these phases can exist in a variety of solid solutions that differ from the idealized forms observed in single crystals in nature. The lack of understanding of the durability of these stoichiometric or idealized mineral phases complicates the ability to deconvolute the durability of the mixed phase FBSR product since it is a combination of different NAS phases. To better understand the behavior, fabrication and testing of the individual phases of the FBSR product is required. Analytical Development (AD) of the Science and Technology directorate of the Savannah River National Laboratory (SRNL) was requested to prepare the series of phase-pure standards, consisting of nepheline, nosean, and Cl, Re, and I sodalite. Once prepared, X-ray Diffraction (XRD) analyses were used to confirm the products were phase pure. These standards are being used for subsequent characterization studies consisting of the following: single-pass flow-through (SPFT) testing, development of thermodynamic data, and x-ray diffraction (XRD) calibration curves. In addition to the above mentioned phase-pure standards, AD was tasked with fabricating a mixed Tc-Re sodalite.

  15. Synthesis And Characterization Of Pure-Silica- Zeolite-Beta Membrane

    Directory of Open Access Journals (Sweden)

    Yeong Yin Fong

    2017-11-01

    Full Text Available The semiconductor industry needs low dielectric constant (low k-value materials to more advance microprocessor and chips by reducing the size of the device features. In fabricate this context, a new material with lower k value than conventional silica ( k = 3.9 - 4.2 is needed in order to improve the circuit performance. As per the recent International Semiconductor Technology plan, a low-k material with a k = 1.6 will be needed by 2010. The choice of the inorganic zeolite membrane is an attractive option for low k material and suitable for microprocess application.  In the present study, a pure silica zeolite beta membrane coated on the non-porous stainless steel support was synthesized using in situ crystallization of a gel with the composition of  SiO2 : 0.6 TEAOH : 0.6 HF : 10.1 H2O. The crystallization was carried in the presence of tetraethylammonium hydroxide TEA(OH as structure directing agent, fumed silica, HF and deionized water at pH value of 9. The crystallization under hydrothermal conditions at 130oC was carried out for the time period of 14 days. The membrane was characterized by X-Ray Diffraction ( XRD ,  Thermogravimetric Analysis ( TGA , Nitrogen Adsorption and Scanning Electron Microscope ( SEM .   SEM micrographs show highly crystalline, truncated square bipyramidal morphology of pure silica zeolite beta was coated on the non-porous stainless steel support. The membrane dielectric constant, k-value was measured as 2.64 which makes it suitable for the microprocessor applications.

  16. Synthesis and characterization of pure and Tb/Cu doped Alq{sub 3} nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Salah, Numan, E-mail: nsalah@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Habib, Sami S. [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Khan, Zishan H. [Department of Applied Sciences, Faculty of Engineering and Technology, Jamia Millia, Islamia (Central University), New Delhi 110025 (India); Alharbi, Najlaa D. [Center of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Sciences Faculty for Girls, King Abdulaziz University, Jeddah-21589 (Saudi Arabia)

    2013-11-15

    Tris (8-hydroxyquinoline) aluminum (Alq{sub 3}) is an organic semiconductor molecule, widely used in optoelectronic devices. In this work we report on fabricating different nanostructures of Alq{sub 3} and characterize them using different techniques. Nanostructured films of Alq{sub 3} were grown using the physical vapor condensation and thermal-vapor transport methods. The as synthesized films were characterized by X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and absorption spectra. Nanoparticles and nanorods/nanowires are observed in the synthesized films. Tb and Cu doped Alq{sub 3} films were also produced and studied for their photoluminescence (PL) properties. When the original powder sample of Alq{sub 3} was excited by 378 nm, one broad PL emission band is observed at around 515 nm. The pure nanoparticles film shows similar band with a drastic increase in the intensity by a factor of 2. This has been attributed to the large specific surface area, which might has increased the absorption and then the quantum yields. The Tb and Cu doped films show also similar band with a slight shift in the peak position to the blue region, but with further enhancement in the peak intensity, particularly that of Cu. The PL intensity of Cu doped sample is around 1.5 times stronger than that of the pure Alq{sub 3} nanoparticles. This remarkable result on obtaining highly luminescent nanomaterial based on Cu doped Alq{sub 3} nanoparticles film might be useful for future organic light emitting diode display devices. -- Highlights: • Films of Alq{sub 3} nanostructures were grown using different methods. • The PL intensity of Alq{sub 3} in its nanostructure form is enhanced by a factor of 2. • This enhancement is attributed to the large specific surface area of the nanostructures. • Films of Alq{sub 3} nanoparticles doped with Tb and Cu showed further PL enhancement. • The Tb and Cu ions could contribute to the PL intensity of the green

  17. Synthesis, Characterization, and Magnetic Properties of Pure and EDTA-Capped NiO Nanosized Particles

    Directory of Open Access Journals (Sweden)

    H. T. Rahal

    2017-01-01

    Full Text Available The effect of ethylenediaminetetraacetic acid (EDTA as a capping agent on the structure, morphology, optical, and magnetic properties of nickel oxide (NiO nanosized particles, synthesized by coprecipitation method, was investigated. Nickel chloride hexahydrate and sodium hydroxide (NaOH were used as precursors. The resultant nanoparticles were characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, and scanning electron microscopy (SEM. XRD patterns showed that NiO have a face-centered cubic (FCC structure. The crystallite size, estimated by Scherrer formula, has been found in the range of 28–33 nm. It is noticed that EDTA-capped NiO nanoparticles have a smaller size than pure nanoparticles. Thus, the addition of 0.1 M capping agent EDTA can form a nucleation point for nanoparticles growth. The optical and magnetic properties were investigated by Fourier transform infrared spectroscopy (FTIR and UV-vis absorption spectroscopy (UV as well as electron paramagnetic resonance (EPR and magnetization measurements. FTIR spectra indicated the presence of absorption bands in the range of 402–425 cm−1, which is a common feature of NiO. EPR for NiO nanosized particles was measured at room temperature. An EPR line with g factor ≈1.9–2 is detected for NiO nanoparticles, corresponding to Ni2+ ions. The magnetic hysteresis of NiO nanoparticles showed that EDTA capping recovers the surface magnetization of the nanoparticles.

  18. Preparation and characterization of enamel coating on pure titanium as a hydrogen penetration barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Jie, E-mail: taojie@nuaa.edu.cn [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China); Guo, Xunzhong [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China); Huang, Zhendong [Graduate School of Human and Environmental Studies, Kyoto University, oshida-Nihonmatsu-Cho, Sakyo-Ku, Kyoto shi 606-8501 (Japan); Liu, Hongbing [Shanghai Aircraft Manufacturing Co,. Ltd, Shanghai 200436 (China); Wang, Tao [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China)

    2013-06-15

    Highlights: ► The enamel coating was prepared by spin-coating and enameling method. ► The dense enamel coatings were chemically bonded with TA1 substrate. ► The coatings possessed better thermal shock resistance property. ► The coatings had excellent ball-dropping impact properties. ► The enamel coating exhibited a good barrier effect to hydrogen isotope penetration. -- Abstract: The enamel coating with a thickness of 90–110 × 10{sup −6} m was prepared on TA1 substrate by spin-coating and enameling to solve the problems of hydrogen isotope penetration for commercial pure titanium TA1. The microstructure and the interfacial morphology of the samples were characterized respectively by X-ray diffraction, optical and scanning electron microscopy. The profiles of main elements at the interface were analyzed by EDS line-scanning. The experimental results indicated that the dense enamel coatings were chemically bonded with TA1 substrate, and possessed better thermal shock resistance and ball-dropping impact properties. It was concluded from the results of hydrogen charging test with Vickers microhardness measurement and deuterium penetration experiments that the as-prepared dense enamel coating exhibited a good barrier effect to hydrogen isotope penetration.

  19. Construction and characterization of a pure protein hydrogel for drug delivery application.

    Science.gov (United States)

    Xu, Xu; Xu, ZhaoKang; Yang, XiaoFeng; He, YanHao; Lin, Rong

    2017-02-01

    Injectable hydrogels have a variety of applications, including regenerative medicine, tissue engineering and controlled drug delivery. In this paper, we reported on a pure protein hydrogel based on tetrameric recombinant proteins for the potential drug delivery application. This protein hydrogel was formed instantly by simply mixing two recombinant proteins (ULD-TIP1 and ULD-GGGWRESAI) through the specific protein-peptide interaction. The protein hydrogel was characterized by rheology and scanning electron microscopy (SEM). In vitro cytotoxicity test indicated that the developed protein hydrogel had no apparent cytotoxicity against L-929 cells and HCEC cells after 48h incubation. The formed protein hydrogels was gradually degraded after incubation in phosphate buffered solution (PBS, pH=7.4) for a period of 144h study, as indicated by in vitro degradation test. Encapsulation of model drug (sodium diclofenac; DIC) were achieved by simple mixing of drugs with hydrogelator and the entrapped drugs was almost completely released from hydrogels within 24h via a diffusion manner. As a conclusion, the simple and mild preparation procedure and good biocompatibility of protein hydrogel would render its good promising candidate for drug delivery applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. MicroRNA and histopathological characterization of pure mucinous breast carcinoma

    International Nuclear Information System (INIS)

    Zhou, Feng; Li, Shuai; Meng, Hui-Min; Qi, Li-Qiang; Gu, Lin

    2013-01-01

    Pure mucinous breast carcinoma (PMBC) is an uncommon histological type of breast cancer characterized by a large amount of mucin production. MicroRNA (miRNA) is a large class of small noncoding RNA of about 22 nt involved in the regulation of various biological processes. This study aims to identify the miRNA expression profile in PMBC. MiRNA expression profiles in 11 PMBCs were analyzed by miRNA-microarray and real-time polymerase chain reaction (PCR). Thirty-one PMBCs and 27 invasive ductal carcinoma of no special types (IDC-NSTs) were assessed by immunohistochemistry using antibodies against ER, PR-progesterone receptor, HER2, Ki-67, Bcl-2, p53, PCNA, and CK5 and 6. We analyzed the miRNA expression in 11 PMBCs and corresponding normal tissues using miRNA-microarray and real-time PCR, and found that miR-143 and miR-224-5p were significantly downregulated in mucinous carcinoma tissue. Compared with IDC-NSTs, PMBC showed a significantly higher ER positive rate, lower HER-2 positive rate, and lower cell proliferation rates. To our knowledge, this is the first study to demonstrate the miRNA expression profile of PMBC, and our findings may lead to further understanding of this type of breast cancer

  1. Relationship between water activity, deformation speed, and crispness characterization

    NARCIS (Netherlands)

    Castro Prada, E.M.; Primo Martin, C.; Meinders, M.B.J.; Hamer, R.J.; Vliet, van T.

    2009-01-01

    Very little is known on the rate dependency of the fracture behavior of crispy products as a function of water activity (Aw). Therefore, the effect of deformation speed on instrumental and sensory crispness was studied as a function of Aw. Deformation speed clearly affects the transition Aw range

  2. High-Speed Thermal Characterization of Cryogenic Flows, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna proposes to continue development on a high-speed fiber optic sensor and readout system for cryogenic temperature measurements in liquid oxygen (LOX) and liquid...

  3. Surface-treated commercially pure titanium for biomedical applications: Electrochemical, structural, mechanical and chemical characterizations

    International Nuclear Information System (INIS)

    Ogawa, Erika S.; Matos, Adaias O.; Beline, Thamara; Marques, Isabella S.V.; Sukotjo, Cortino; Mathew, Mathew T.; Rangel, Elidiane C.; Cruz, Nilson C.; Mesquita, Marcelo F.; Consani, Rafael X.

    2016-01-01

    Modified surfaces have improved the biological performance and biomechanical fixation of dental implants compared to machined (polished) surfaces. However, there is a lack of knowledge about the surface properties of titanium (Ti) as a function of different surface treatment. This study investigated the role of surface treatments on the electrochemical, structural, mechanical and chemical properties of commercial pure titanium (cp-Ti) under different electrolytes. Cp-Ti discs were divided into 6 groups (n = 5): machined (M—control); etched with HCl + H_2O_2 (Cl), H_2SO_4 + H_2O_2 (S); sandblasted with Al_2O_3 (Sb), Al_2O_3 followed by HCl + H_2O_2 (SbCl), and Al_2O_3 followed by H_2SO_4 + H_2O_2 (SbS). Electrochemical tests were conducted in artificial saliva (pHs 3; 6.5 and 9) and simulated body fluid (SBF—pH 7.4). All surfaces were characterized before and after corrosion tests using atomic force microscopy, scanning electron microscopy, energy dispersive microscopy, X-ray diffraction, surface roughness, Vickers microhardness and surface free energy. The results indicated that Cl group exhibited the highest polarization resistance (R_p) and the lowest capacitance (Q) and corrosion current density (I_c_o_r_r) values. Reduced corrosion stability was noted for the sandblasted groups. Acidic artificial saliva decreased the R_p values of cp-Ti surfaces and produced the highest I_c_o_r_r values. Also, the surface treatment and corrosion process influenced the surface roughness, Vickers microhardness and surface free energy. Based on these results, it can be concluded that acid-etching treatment improved the electrochemical stability of cp-Ti and all treated surfaces behaved negatively in acidic artificial saliva. - Highlights: • Characterization of surface treatment for biomedical implants was investigated. • Sandblasting reduced the corrosion stability of cp-Ti. • Acid etching is a promising dental implants surface treatment.

  4. Surface-treated commercially pure titanium for biomedical applications: Electrochemical, structural, mechanical and chemical characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Erika S.; Matos, Adaias O.; Beline, Thamara [Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av Limeira, 901, Piracicaba, São Paulo 13414-903 (Brazil); IBTN/Br—Institute of Biomaterials, Tribocorrosion and Nanomedicine—Brazilian Branch (Brazil); Marques, Isabella S.V. [Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av Limeira, 901, Piracicaba, São Paulo 13414-903 (Brazil); Sukotjo, Cortino [Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, 801 S Paulina, Chicago, IL, USA, 60612 (United States); IBTN—Institute of Biomaterials, Tribocorrosion and Nanomedicine (United States); Mathew, Mathew T. [IBTN—Institute of Biomaterials, Tribocorrosion and Nanomedicine (United States); Department of Biomedical Sciences, University of Illinois, College of Medicine at Rockford, 1601 Parkview Avenue, Rockford, IL, USA, 61107 (United States); Rangel, Elidiane C.; Cruz, Nilson C. [IBTN/Br—Institute of Biomaterials, Tribocorrosion and Nanomedicine—Brazilian Branch (Brazil); Laboratory of Technological Plasmas, Engineering College, Univ Estadual Paulista (UNESP), Av Três de Março, 511, Sorocaba, São Paulo 18087-180 (Brazil); Mesquita, Marcelo F.; Consani, Rafael X. [Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av Limeira, 901, Piracicaba, São Paulo 13414-903 (Brazil); and others

    2016-08-01

    Modified surfaces have improved the biological performance and biomechanical fixation of dental implants compared to machined (polished) surfaces. However, there is a lack of knowledge about the surface properties of titanium (Ti) as a function of different surface treatment. This study investigated the role of surface treatments on the electrochemical, structural, mechanical and chemical properties of commercial pure titanium (cp-Ti) under different electrolytes. Cp-Ti discs were divided into 6 groups (n = 5): machined (M—control); etched with HCl + H{sub 2}O{sub 2} (Cl), H{sub 2}SO{sub 4} + H{sub 2}O{sub 2} (S); sandblasted with Al{sub 2}O{sub 3} (Sb), Al{sub 2}O{sub 3} followed by HCl + H{sub 2}O{sub 2} (SbCl), and Al{sub 2}O{sub 3} followed by H{sub 2}SO{sub 4} + H{sub 2}O{sub 2} (SbS). Electrochemical tests were conducted in artificial saliva (pHs 3; 6.5 and 9) and simulated body fluid (SBF—pH 7.4). All surfaces were characterized before and after corrosion tests using atomic force microscopy, scanning electron microscopy, energy dispersive microscopy, X-ray diffraction, surface roughness, Vickers microhardness and surface free energy. The results indicated that Cl group exhibited the highest polarization resistance (R{sub p}) and the lowest capacitance (Q) and corrosion current density (I{sub corr}) values. Reduced corrosion stability was noted for the sandblasted groups. Acidic artificial saliva decreased the R{sub p} values of cp-Ti surfaces and produced the highest I{sub corr} values. Also, the surface treatment and corrosion process influenced the surface roughness, Vickers microhardness and surface free energy. Based on these results, it can be concluded that acid-etching treatment improved the electrochemical stability of cp-Ti and all treated surfaces behaved negatively in acidic artificial saliva. - Highlights: • Characterization of surface treatment for biomedical implants was investigated. • Sandblasting reduced the corrosion stability of cp

  5. Obtainment and characterization of pure and doped gadolinium oxy ortho silicates with terbium III, precursor of luminescent silicates with sulphur

    International Nuclear Information System (INIS)

    Simoneti, J.A.

    1992-01-01

    Silicate and sulfide lattices are uniquely efficient luminescent materials to excitation by cathodic rays and furthermore the cathodoluminescence study of these compounds have been few investigated. In this work it has been prepared, characterized and investigated some spectroscopic properties of pure and Tb a+ - activated Gd 2 Si O 3 system and it has been tried to substitute oxygen by sulphur in order to obtain this or sulfide-silicate lattices. Products were characterized by vibrational infrared spectroscopy, powder X-ray diffraction patterns and electronic emission in UV-VIS region. (author)

  6. Synthesis and characterization of nano- and microcrystalline cubes of pure and Ag-doped LiF

    Science.gov (United States)

    Alharbi, Najlaa D.; Salah, Numan; Habib, Sami S.; Alarfaj, Esam

    2013-01-01

    Lithium fluoride (LiF) produced in single crystals and doped with proper activators is a highly sensitive phosphor used in several applications such as integrated optics, colour centre laser and radiation dosimetry. In this work, we have developed a new synthetic chemical co-precipitation route for the synthesis of well-crystallized micro- and nanocrystalline cubes of pure and silver (Ag)-doped LiF. The as-synthesized samples were characterized by x-ray diffraction (XRD), scanning electron microscopy, absorption spectrum, photoluminescence (PL) and Raman spectroscopy. Size of the produced cubes could be controlled in the range 10 µm-50 nm by varying the solvent : co-solvent ratio. Micro-sized cubes could be grown in the presence of water as a solvent, while ethanol, which acts as a co-solvent, is found to be effective in reducing the size to the nanoscale. XRD results show complete crystalline structures in a griceite phase. The PL result of pure nanocubes exhibits a broad band in the range 370-550 nm, while that doped with Ag shows a prominent band at 420 nm. Raman spectra of the pure and Ag-doped LiF samples display several bands located in the range 80-236 cm-1. These results show that pure nanocubes of LiF have active colour centres without irradiation, which could be enhanced/modified by Ag dopants. This implies that these nanocubes might be useful in the development of optical devices.

  7. Synthesis and characterization of nano- and microcrystalline cubes of pure and Ag-doped LiF

    International Nuclear Information System (INIS)

    Alharbi, Najlaa D; Salah, Numan; Habib, Sami S; Alarfaj, Esam

    2013-01-01

    Lithium fluoride (LiF) produced in single crystals and doped with proper activators is a highly sensitive phosphor used in several applications such as integrated optics, colour centre laser and radiation dosimetry. In this work, we have developed a new synthetic chemical co-precipitation route for the synthesis of well-crystallized micro- and nanocrystalline cubes of pure and silver (Ag)-doped LiF. The as-synthesized samples were characterized by x-ray diffraction (XRD), scanning electron microscopy, absorption spectrum, photoluminescence (PL) and Raman spectroscopy. Size of the produced cubes could be controlled in the range 10 µm-50 nm by varying the solvent:co-solvent ratio. Micro-sized cubes could be grown in the presence of water as a solvent, while ethanol, which acts as a co-solvent, is found to be effective in reducing the size to the nanoscale. XRD results show complete crystalline structures in a griceite phase. The PL result of pure nanocubes exhibits a broad band in the range 370-550 nm, while that doped with Ag shows a prominent band at 420 nm. Raman spectra of the pure and Ag-doped LiF samples display several bands located in the range 80-236 cm -1 . These results show that pure nanocubes of LiF have active colour centres without irradiation, which could be enhanced/modified by Ag dopants. This implies that these nanocubes might be useful in the development of optical devices.

  8. Manufacturing and Characterization of Ultra Pure Ferrous Alloys Final Report CRADA No. TC02069.0

    Energy Technology Data Exchange (ETDEWEB)

    Lesuer, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McGreevy, T. E. [Caterpillar Inc., Mossville, IL (United States)

    2017-09-06

    This CRADA was a.collaborative effort between the Lawrence Livermore National Security LLC (formerly University of California)/Lawrence Livermore National Laboratory (LLNL),and Caterpillar Inc. (CaterpiHar), to further advance levitation casting techniques (developed at the Central Research Institute for Material (CRIM) in St. Petersburg, Russia) for use in manufacturing high purity metal alloys. This DOE Global Initiatives for Proliferation Prevention Program (IPP) project was to develop and demonstrate the levitation casting technology for producing ultra-pure alloys.

  9. Characterization of Input Current Interharmonics in Adjustable Speed Drives

    DEFF Research Database (Denmark)

    Soltani, Hamid; Davari, Pooya; Zare, Firuz

    2017-01-01

    This paper investigates the interharmonic generation process in the input current of double-stage Adjustable Speed Drives (ASDs) based on voltage source inverters and front-end diode rectifiers. The effects of the inverter output-side low order harmonics, caused by implementing the double......-edge symmetrical regularly sampled Space Vector Modulation (SVM) technique, on the input current interharmonic components are presented and discussed. Particular attention is also given to the influence of the asymmetrical regularly sampled modulation technique on the drive input current interharmonics....... The developed theoretical analysis predicts the drive interharmonic frequency locations with respect to the selected sampling strategies. Simulation and experimental results on a 2.5 kW ASD system verify the effectiveness of the theoretical analysis....

  10. Use of accelerators in activation analysis, specially for the characterization of pure substances

    International Nuclear Information System (INIS)

    Engelmann, C.

    1979-01-01

    The principal means of activation, their respective potential performance and their preferential fields of application are briefly reviewed. The possibilities offered by charged particles and gamma photons where the determination of light elements or of other impurities is concerned, in pure substances, are discussed. Examples, relating to the evaluation of boron, carbon, nitrogen, oxygen or fluorine levels in metals (Na, Al, Ti, Ni, Cu, Zr, Mo, Ta, W, Pb, etc.), in alloys (PbCuTe, PbSnCd) and in semiconductors (Si, AsGa, InP, etc.) are presented. Where some of these products are concerned, the results obtained by nuclear methods are compared with the values provided by other analytical techniques. The superiority of the first, when the concentration levels of these impurities are less than 1 μg.g -1 , is clearly apparent [fr

  11. Synthesis, characterizations and anti-bacterial activities of pure and Ag doped CdO nanoparticles by chemical precipitation method.

    Science.gov (United States)

    Sivakumar, S; Venkatesan, A; Soundhirarajan, P; Khatiwada, Chandra Prasad

    2015-02-05

    In the present study, synthesized pure and Ag (1%, 2%, and 3%) doped Cadmium Oxide (CdO) nanoparticles by chemical precipitation method. Then, the synthesized products were characterized by thermo gravimetric-differential thermal analysis (TG-DTA), X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, Ultra violet-Vis diffused reflectance spectroscopy (UV-Vis-DRS), Scanning electron microscopy (SEM), Energy dispersive X-rays (EDX) spectroscopy, and anti-bacterial activities, respectively. The transition temperatures and phase transitions of Cd(OH)2 to CdO at 400°C was confirmed by TG-DTA analysis. The XRD patterns show the cubic shape and average particle sizes are 21, 40, 34, and 37nm, respectively for pure and Ag doped samples. FT-IR study confirmed the presence of CdO and Ag at 677 and 459cm(-1), respectively. UV-Vis-DRS study shows the variation on direct and indirect band gaps. The surface morphologies and elemental analysis have been confirmed from SEM and with EDX. In addition, the synthesized products have been characterized by antibacterial activities against Gram-positive and negative bacteria. Further, the present investigation suggests that CdO nanoparticles have the great potential applications on various industrial and medical fields of research. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Characterizing occipital condyle loads under high-speed head rotation.

    Science.gov (United States)

    Pintar, Frank A; Yoganandan, Narayan; Baisden, Jamie

    2005-11-01

    Because of the need to evaluate anthropomorphic test device (ATD) biofidelity under high-head angular accelerations, the purpose of the present investigation was to develop appropriate instrumentation for intact post mortem human subject (PMHS) testing, validate the instrumentation, and obtain information to characterize the response of the head-neck complex under this loading scenario. A series of rigid-arm pendulum, inertially loaded ATD tests was conducted. Head and neck ATD hydraulic piston chin pull tests were conducted. Subsequently, a series of PMHS tests was conducted to derive the response of the human head-neck under high-rate chin loading. Finally, Hybrid III and THOR-NT ATD head-neck systems were evaluated under the same scenario as the PMHS. A parametric analysis for center of gravity (CG) location and accelerometer orientation determined that even small errors (+/- 3 mm or 2 degrees), produced errors in the force and moment calculations by as much as 17 %. If the moment of inertia (MOI) term was varied by 5 %, resulting moment calculations were affected by as much as 8 %. If the 5 % error in MOI was used to compute occipital condyle moments, and results compared to upper load cell derived moments, peaks differed by as much as 24 %. The head CG and mass MOI should be directly measured for each preparation to obtain accurate results. The injury run on each specimen resulted in predominantly C1-C2 separations or partial separations. The 50(th) percentile probability of AIS=2+ neck injury using tensile force was about 2400 N; for AIS=3+ neck injury the 50(th) percentile risk was about 3180 N. When inserting extension moment as the criteria, the 50(th) percentile probability of an AIS=2+ injury was 51 Nm. The AIS=3+ extension moment at the 50(th) percentile probability was 75 Nm. The new THOR-NT ATD head-neck produced more biofidelic responses with an alternate head-neck junction design compared to the Hybrid III ATD.

  13. Characterization of Powder Metallurgy Processed Pure Magnesium Materials for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Matěj Březina

    2017-10-01

    Full Text Available Magnesium with its mechanical properties and nontoxicity is predetermined as a material for biomedical applications; however, its high reactivity is a limiting factor for its usage. Powder metallurgy is one of the promising methods for the enhancement of material mechanical properties and, due to the introduced plastic deformation, can also have a positive influence on corrosion resistance. Pure magnesium samples were prepared via powder metallurgy. Compacting pressures from 100 MPa to 500 MPa were used for samples’ preparation at room temperature and elevated temperatures. The microstructure of the obtained compacts was analyzed in terms of microscopy. The three-point bendisng test and microhardness testing were adopted to define the compacts’ mechanical properties, discussing the results with respect to fractographic analysis. Electrochemical corrosion properties analyzed with electrochemical impedance spectroscopy carried out in HBSS (Hank’s Balanced Salt Solution and enriched HBSS were correlated with the metallographic analysis of the corrosion process. Cold compacted materials were very brittle with low strength (up to 50 MPa and microhardness (up to 50 HV (load: 0.025 kg and degraded rapidly in both solutions. Hot pressed materials yielded much higher strength (up to 250 MPa and microhardness (up to 65 HV (load: 0.025 kg, and the electrochemical characteristics were significantly better when compared to the cold compacted samples. Temperatures of 300 °C and 400 °C and high compacting pressures from 300 MPa to 500 MPa had a positive influence on material bonding, mechanical and electrochemical properties. A compacting temperature of 500 °C had a detrimental effect on material compaction when using pressure above 200 MPa.

  14. Characterization of nanostructured pure aluminum tubes produced by tubular channel angular pressing (TCAP)

    Energy Technology Data Exchange (ETDEWEB)

    Mesbah, M. [Centre of Advanced Manufacturing and Material Processing, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Faraji, G., E-mail: ghfaraji@ut.ac.ir [School of Mechanical Engineering, College of Engineering, University of Tehran, 11155-4563 Tehran (Iran, Islamic Republic of); Centre of Advanced Manufacturing and Material Processing, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Bushroa, A.R. [Centre of Advanced Manufacturing and Material Processing, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-01-10

    Ultrafine grained (UFG) aluminum tubes were fabricated by the tubular channel angular pressing (TCAP) process. The microstructural evolution was characterized by transmission electron microscopy (TEM) and mechanical properties were evaluated by compression test and hardness measurements. TEM analysis of specimen subjected to one TCAP pass showed the formation of an array of elongated subgrains with high angle grain boundaries. Increase in the number of passes changes the elongated grains to equiaxed grains with ∼310 nm sizes. Microhardness value of the processed tubes was enhanced to 49.4 Hv after one pass from an initial value of 32.9 Hv. Yield and ultimate strengths were increased 2.5 and 2.28 times as compared to annealed specimen. Compression tests also showed that UFG aluminum tubes exhibit lower work hardening and almost perfect plastic behavior without any failure.

  15. Characterization of nanostructured pure aluminum tubes produced by tubular channel angular pressing (TCAP)

    International Nuclear Information System (INIS)

    Mesbah, M.; Faraji, G.; Bushroa, A.R.

    2014-01-01

    Ultrafine grained (UFG) aluminum tubes were fabricated by the tubular channel angular pressing (TCAP) process. The microstructural evolution was characterized by transmission electron microscopy (TEM) and mechanical properties were evaluated by compression test and hardness measurements. TEM analysis of specimen subjected to one TCAP pass showed the formation of an array of elongated subgrains with high angle grain boundaries. Increase in the number of passes changes the elongated grains to equiaxed grains with ∼310 nm sizes. Microhardness value of the processed tubes was enhanced to 49.4 Hv after one pass from an initial value of 32.9 Hv. Yield and ultimate strengths were increased 2.5 and 2.28 times as compared to annealed specimen. Compression tests also showed that UFG aluminum tubes exhibit lower work hardening and almost perfect plastic behavior without any failure

  16. Characterization of Vocal Fold Vibration in Sulcus Vocalis Using High-Speed Digital Imaging

    Science.gov (United States)

    Yamauchi, Akihito; Yokonishi, Hisayuki; Imagawa, Hiroshi; Sakakibara, Ken-Ichi; Nito, Takaharu; Tayama, Niro; Yamasoba, Tatsuya

    2017-01-01

    Purpose: The aim of the present study was to qualitatively and quantitatively characterize vocal fold vibrations in sulcus vocalis by high-speed digital imaging (HSDI) and to clarify the correlations between HSDI-derived parameters and traditional vocal parameters. Method: HSDI was performed in 20 vocally healthy subjects (8 men and 12 women) and…

  17. Some studies on mechanical properties and microstructural characterization of automated TIG welding of thin commercially pure titanium sheets

    Energy Technology Data Exchange (ETDEWEB)

    Karpagaraj, A.; Siva shanmugam, N., E-mail: nsiva@nitt.edu; Sankaranarayanasamy, K.

    2015-07-29

    Gas Tungsten Arc Welding (GTAW) is a commonly used welding process for welding Titanium materials. Welding of titanium and its alloys poses several intricacies to the designer as they are prone to oxidation phenomenon. To overcome this contamination, a relatively new type of shielding arrangement is experimented. The proposed design and arrangement have been employed for joining commercially pure titanium sheets with variations in the GTAW process parameters namely the welding current and travel speed. Bead on plate (BoP) trials were conducted on thin sheets of 2 mm thickness by varying the process parameters. Subsequently, the macro structure images were captured. Based on these results, the process parameters are chosen for carrying out full penetration butt joints on 1.6 mm and 2 mm thick titanium sheets. The influences of these parameters of GTAW on the microstructure, mechanical properties and surface morphology at the fractured locations of the welded joints are examined. The microstructural properties of base metal, heat affected zone and fusion zone are analyzed through optical microscopy. The welded joints showed an ultimate tensile strength of about 383 MPa with 15.7% elongation. The hardness value at fusion zone and base metal are typically observed to be 191 and 153 HV-0.5, respectively. X-ray diffraction study is conducted to examine the chemical composition in the parent metal and fusion zone of the weld. Fractured surface is examined using Scanning Electron Microscopy which revealed dimple kind of rupture present at the fractured surfaces owing to insufficient or excessive heat with slight impurities that prevents the accomplishment of stronger micro-level weld integrity.

  18. Some studies on mechanical properties and microstructural characterization of automated TIG welding of thin commercially pure titanium sheets

    International Nuclear Information System (INIS)

    Karpagaraj, A.; Siva shanmugam, N.; Sankaranarayanasamy, K.

    2015-01-01

    Gas Tungsten Arc Welding (GTAW) is a commonly used welding process for welding Titanium materials. Welding of titanium and its alloys poses several intricacies to the designer as they are prone to oxidation phenomenon. To overcome this contamination, a relatively new type of shielding arrangement is experimented. The proposed design and arrangement have been employed for joining commercially pure titanium sheets with variations in the GTAW process parameters namely the welding current and travel speed. Bead on plate (BoP) trials were conducted on thin sheets of 2 mm thickness by varying the process parameters. Subsequently, the macro structure images were captured. Based on these results, the process parameters are chosen for carrying out full penetration butt joints on 1.6 mm and 2 mm thick titanium sheets. The influences of these parameters of GTAW on the microstructure, mechanical properties and surface morphology at the fractured locations of the welded joints are examined. The microstructural properties of base metal, heat affected zone and fusion zone are analyzed through optical microscopy. The welded joints showed an ultimate tensile strength of about 383 MPa with 15.7% elongation. The hardness value at fusion zone and base metal are typically observed to be 191 and 153 HV-0.5, respectively. X-ray diffraction study is conducted to examine the chemical composition in the parent metal and fusion zone of the weld. Fractured surface is examined using Scanning Electron Microscopy which revealed dimple kind of rupture present at the fractured surfaces owing to insufficient or excessive heat with slight impurities that prevents the accomplishment of stronger micro-level weld integrity

  19. Pure phase LaFeO3 perovskite with improved surface area synthesized using different routes and its characterization

    International Nuclear Information System (INIS)

    Gosavi, Priti V.; Biniwale, Rajesh B.

    2010-01-01

    Three different wet chemistry routes, namely co-precipitation, combustion and sol-gel methods were used to synthesize LaFeO 3 perovskite with improved surface area. The synthesized perovskite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), Brunauer-Emmett-Teller (BET) nitrogen adsorption, ultraviolet diffused reflectance spectroscopy (UVDRS) and Fourier transform infrared (FTIR) spectroscopy techniques. Improved surface area was observed for all three methods as compared to the previously reported values. The perovskite synthesized using sol-gel method yields comparatively pure, crystalline phase of LaFeO 3 and relatively higher surface area of 16.5 m 2 g -1 and porosity. The material synthesized using co-precipitation method yielded other phases in addition to the targeted phase. The morphology of perovskite synthesized using co-precipitation method was uniform agglomerates. Combustion method yields flakes type morphology and that of sol-gel method was open pore type morphology. The selection of method for perovskite synthesis largely depends on the targeted application and the desired properties of perovskites. The results reported in this study are useful for establishing a simple scalable method for preparation of high surface area LaFeO 3 as compared to solid-oxide method. Further, the typical heating cycle followed for calcinations resulted in relatively high surface area in the case of all three methods.

  20. Experimental Characterization of LTE Wireless Links in High-Speed Trains

    Directory of Open Access Journals (Sweden)

    Tomás Domínguez-Bolaño

    2017-01-01

    Full Text Available Multimedia and data-based services experienced a nonstopping growth over the last few years. People are continuously on the move using devices to access multimedia contents or other data-based services. Due to this, railway companies are showing a great interest in deploying broadband mobile wireless networks in high-speed-trains with the aim of supporting both passenger services provisioning as well as automatic train control and signaling. Nowadays, the most widely used technology for communications between trains and the railway infrastructure is GSM for Railways (GSM-R; however, it has limited capabilities to support such advanced services. Due to its success in the mass market, Long Term Evolution (LTE seems to be the best candidate to substitute GSM-R. In this paper, we experimentally characterize the downlink between an LTE Evolved NodeB (eNodeB and a high-speed train in a commercial high-speed line. We consider two links: the one between the eNodeB and the antennas placed outdoors on the train roof, and the direct link between the eNodeB and a receiver inside the train. Such a characterization consists in assessing the path loss, the Signal to Noise Ratio, the K-Factor, the Power Delay Profile, the delay spread, and the Doppler Power Spectral Density.

  1. High-Speed Printing Process Characterization using the Lissajous Trajectory Method

    Science.gov (United States)

    Lee, Sangwon; Kim, Daekeun

    2018-04-01

    We present a novel stereolithographic three-dimensional (3D) printing process that uses Lissajous trajectories. By using Lissajous trajectories, this 3D printing process allows two laser-scanning mirrors to operate at similar high-speed frequencies simultaneously, and the printing speed can be faster than that of raster scanning used in conventional stereolithography. In this paper, we first propose the basic theoretical background for this printing process based on Lissajous trajectories. We also characterize its printing conditions, such as printing size, laser spot size, and minimum printing resolution, with respect to the operating frequencies of the scanning mirrors and the capability of the laser modulation. Finally, we demonstrate simulation results for printing basic 2D shapes by using a noble printing process algorithm.

  2. High-speed infrared imaging for material characterization in experimental mechanics experiments

    Science.gov (United States)

    Gagnon, Marc-André; Marcotte, Frédérick; Lagueux, Philippe; Farley, Vincent; Guyot, Éric; Morton, Vince

    2017-10-01

    Heat transfers are involved in many phenomena such as friction, tensile stress, shear stress and material rupture. Among the challenges encountered during the characterization of such thermal patterns is the need for both high spatial and temporal resolution. Infrared imaging provides information about surface temperature that can be attributed to the stress response of the material and breaking of chemical bounds. In order to illustrate this concept, tensile and shear tests were carried out on steel, aluminum and carbon fiber composite materials and monitored using high-speed (Telops FASTM2K) and high-definition (Telops HD-IR) infrared imaging. Results from split-Hopkinson experiments carried out on a polymer material at high strain-rate are also presented. The results illustrate how high-speed and high-definition infrared imaging in the midwave infrared (MWIR, 3 - 5 μm) spectral range can provide detailed information about the thermal properties of materials undergoing mechanical testing.

  3. Detecting Different Road Infrastructural Elements Based on the Stochastic Characterization of Speed Patterns

    Directory of Open Access Journals (Sweden)

    Mario Muñoz-Organero

    2017-01-01

    Full Text Available The automatic detection of road related information using data from sensors while driving has many potential applications such as traffic congestion detection or automatic routable map generation. This paper focuses on the automatic detection of road elements based on GPS data from on-vehicle systems. A new algorithm is developed that uses the total variation distance instead of the statistical moments to improve the classification accuracy. The algorithm is validated for detecting traffic lights, roundabouts, and street-crossings in a real scenario and the obtained accuracy (0.75 improves the best results using previous approaches based on statistical moments based features (0.71. Each road element to be detected is characterized as a vector of speeds measured when a driver goes through it. We first eliminate the speed samples in congested traffic conditions which are not comparable with clear traffic conditions and would contaminate the dataset. Then, we calculate the probability mass function for the speed (in 1 m/s intervals at each point. The total variation distance is then used to find the similarity among different points of interest (which can contain a similar road element or a different one. Finally, a k-NN approach is used for assigning a class to each unlabelled element.

  4. Physical-Chemical Characterization of Fruit Purees and Relationship with Sensory Analysis Carried out by Infants (12 to 24 mo).

    Science.gov (United States)

    Inarejos-García, A M; Mancebo-Campos, V; Cañizares, P; Llanos, J

    2015-05-01

    Fruit purees are one of the foods earliest introduced foods in infants' diet during the complementary period. The rheological characteristics together with the sensory analysis are decisive factors for the acceptance of the food product by the infant. The sensory analysis of three commercial fruit purees (mixed fruits, pear, and plum) was studied by employing a new objective sensory parameter named as SAIR (Sensory Acceptance by Infants Ratio), which is the quotient between the percentage of puree consumed (%) by the time (seconds) throughout the storage time. In parallel, the rheological characteristics of the purees were analyzed in order to obtain a relationship with the SAIR parameter. It was proved that the best acceptance of the product (higher SAIR) was observed for such purees showing a lower apparent viscosity (lower consistency index, "K") and a less pseudoplastic behavior (higher flow behavior index, "n"). These results may help to obtain higher acceptance values based on easy obtainable and objective parameters. © 2015 Institute of Food Technologists®

  5. Characterization of material parameters for high speed forming and cutting via experiment and inverse simulation

    Science.gov (United States)

    Scheffler, Christian; Psyk, Verena; Linnemann, Maik; Tulke, Marc; Brosius, Alexander; Landgrebe, Dirk

    2018-05-01

    High speed velocity effects in production technology provide a broad range of technological and economic advantages [1, 2]. However, exploiting them necessitates the knowledge of strain rate dependent material behavior in process modelling. In general, high speed material data characterization features several difficulties and requires sophisticated approaches in order to provide reliable material data. This paper proposes two innovative concepts with electromagnetic and pneumatic drive and an approach for material characterization in terms of strain rate dependent flow curves and parameters of failure or damage models. The test setups have been designed for investigations of strain rates up to 105 s-1. In principle, knowledge about the temporary courses and local distributions of stress and strain in the specimen is essential for identifying material characteristics, but short process times, fast changes of the measurement values, small specimen size and frequently limited accessibility of the specimen during the test hinder directly measuring these parameters at high-velocity testing. Therefore, auxiliary test parameters, which are easier to measure, are recorded and used as input data for an inverse numerical simulation that provides the desired material characteristics, e.g. the Johnson-Cook parameters, as a result. These parameters are a force equivalent strain signal on a measurement body and the displacement of the upper specimen edge.

  6. A high-speed scintillation-based electronic portal imaging device to quantitatively characterize IMRT delivery.

    Science.gov (United States)

    Ranade, Manisha K; Lynch, Bart D; Li, Jonathan G; Dempsey, James F

    2006-01-01

    We have developed an electronic portal imaging device (EPID) employing a fast scintillator and a high-speed camera. The device is designed to accurately and independently characterize the fluence delivered by a linear accelerator during intensity modulated radiation therapy (IMRT) with either step-and-shoot or dynamic multileaf collimator (MLC) delivery. Our aim is to accurately obtain the beam shape and fluence of all segments delivered during IMRT, in order to study the nature of discrepancies between the plan and the delivered doses. A commercial high-speed camera was combined with a terbium-doped gadolinium-oxy-sulfide (Gd2O2S:Tb) scintillator to form an EPID for the unaliased capture of two-dimensional fluence distributions of each beam in an IMRT delivery. The high speed EPID was synchronized to the accelerator pulse-forming network and gated to capture every possible pulse emitted from the accelerator, with an approximate frame rate of 360 frames-per-second (fps). A 62-segment beam from a head-and-neck IMRT treatment plan requiring 68 s to deliver was recorded with our high speed EPID producing approximately 6 Gbytes of imaging data. The EPID data were compared with the MLC instruction files and the MLC controller log files. The frames were binned to provide a frame rate of 72 fps with a signal-to-noise ratio that was sufficient to resolve leaf positions and segment fluence. The fractional fluence from the log files and EPID data agreed well. An ambiguity in the motion of the MLC during beam on was resolved. The log files reported leaf motions at the end of 33 of the 42 segments, while the EPID observed leaf motions in only 7 of the 42 segments. The static IMRT segment shapes observed by the high speed EPID were in good agreement with the shapes reported in the log files. The leaf motions observed during beam-on for step-and-shoot delivery were not temporally resolved by the log files.

  7. A high-speed scintillation-based electronic portal imaging device to quantitatively characterize IMRT delivery

    International Nuclear Information System (INIS)

    Ranade, Manisha K.; Lynch, Bart D.; Li, Jonathan G.; Dempsey, James F.

    2006-01-01

    We have developed an electronic portal imaging device (EPID) employing a fast scintillator and a high-speed camera. The device is designed to accurately and independently characterize the fluence delivered by a linear accelerator during intensity modulated radiation therapy (IMRT) with either step-and-shoot or dynamic multileaf collimator (MLC) delivery. Our aim is to accurately obtain the beam shape and fluence of all segments delivered during IMRT, in order to study the nature of discrepancies between the plan and the delivered doses. A commercial high-speed camera was combined with a terbium-doped gadolinium-oxy-sulfide (Gd 2 O 2 S:Tb) scintillator to form an EPID for the unaliased capture of two-dimensional fluence distributions of each beam in an IMRT delivery. The high speed EPID was synchronized to the accelerator pulse-forming network and gated to capture every possible pulse emitted from the accelerator, with an approximate frame rate of 360 frames-per-second (fps). A 62-segment beam from a head-and-neck IMRT treatment plan requiring 68 s to deliver was recorded with our high speed EPID producing approximately 6 Gbytes of imaging data. The EPID data were compared with the MLC instruction files and the MLC controller log files. The frames were binned to provide a frame rate of 72 fps with a signal-to-noise ratio that was sufficient to resolve leaf positions and segment fluence. The fractional fluence from the log files and EPID data agreed well. An ambiguity in the motion of the MLC during beam on was resolved. The log files reported leaf motions at the end of 33 of the 42 segments, while the EPID observed leaf motions in only 7 of the 42 segments. The static IMRT segment shapes observed by the high speed EPID were in good agreement with the shapes reported in the log files. The leaf motions observed during beam-on for step-and-shoot delivery were not temporally resolved by the log files

  8. Characterization of condenser microphones under different environmental conditions for accurate speed of sound measurements with acoustic resonators

    Energy Technology Data Exchange (ETDEWEB)

    Guianvarc' h, Cecile; Pitre, Laurent [Laboratoire Commun de Metrologie LNE/Cnam, 61 rue du Landy, 93210 La Plaine Saint Denis (France); Gavioso, Roberto M.; Benedetto, Giuliana [Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, 10135 Turin (Italy); Bruneau, Michel [Laboratoire d' Acoustique de l' Universite du Maine UMR CNRS 6613, av. Olivier Messiaen, 72085 Le Mans Cedex 9 (France)

    2009-07-15

    Condenser microphones are more commonly used and have been extensively modeled and characterized in air at ambient temperature and static pressure. However, several applications of interest for metrology and physical acoustics require to use these transducers in significantly different environmental conditions. Particularly, the extremely accurate determination of the speed of sound in monoatomic gases, which is pursued for a determination of the Boltzmann constant k by an acoustic method, entails the use of condenser microphones mounted within a spherical cavity, over a wide range of static pressures, at the temperature of the triple point of water (273.16 K). To further increase the accuracy achievable in this application, the microphone frequency response and its acoustic input impedance need to be precisely determined over the same static pressure and temperature range. Few previous works examined the influence of static pressure, temperature, and gas composition on the microphone's sensitivity. In this work, the results of relative calibrations of 1/4 in. condenser microphones obtained using an electrostatic actuator technique are presented. The calibrations are performed in pure helium and argon gas at temperatures near 273 K and in the pressure range between 10 and 600 kPa. These experimental results are compared with the predictions of a realistic model available in the literature, finding a remarkable good agreement. The model provides an estimate of the acoustic impedance of 1/4 in. condenser microphones as a function of frequency and static pressure and is used to calculate the corresponding frequency perturbations induced on the normal modes of a spherical cavity when this is filled with helium or argon gas.

  9. Proportion of various dendromass components of spruce (Picea abies), and partial models for modification of wind speed and radiation by pure spruce stands

    International Nuclear Information System (INIS)

    Wollmerstädt, J.; Sharma, S.C.; Marsch, M.

    1992-01-01

    Means for quantifying dendromass components of spruce stands have been discussed, and partial models for modification of radiation and wind by the pure spruce stand were developed. By means of a sampling procedure, the components needle dry mass and branchwood dry mass without needles of individual trees are recorded. Using the relationship between branch basal diameter and needle respectively branchwood dry mass, the total needle and branchwood dry mass of trees is estimated. Based on that, stand or regional parameters for the allometric function between diameter breast height and needle respectively branchwood dry mass can be determined for defined H/D-clusters. Published data from various sources were used in this paper. The lowest coefficients of determination were found in H/D-cluster 120 (H/D-values over 114). Therefore, further differentiation within this range seems to be necessary. For assimilation models, there should be quantification of needle dry mass separately for needle age classes and morphological characteristics of needles. Basis for the estimate of tree-bole volume is the relationship between H/D-value and oven-dry weight. There are problems as far as methods for quantifying the subterranean dendromass (e.g. dynamics of fine roots) are concerned; this is requiring considerable efforts, too. Spatial structure was also described by allometric functions (crown length and crown cover in relation to diameter breast height). For the partial model to express wind modification by the stand, standardized wind profiles as related to crown canopy density were used. The modification of radiation by the stand is closely related with the vertical needle mass distribution (sum curves). These two partial models have to be considered as an approach for the description of the modifying effect by the stocking [de

  10. Characterizing shock waves in hydrogel using high speed imaging and a fiber-optic probe hydrophone

    Science.gov (United States)

    Anderson, Phillip A.; Betney, M. R.; Doyle, H. W.; Tully, B.; Ventikos, Y.; Hawker, N. A.; Roy, Ronald A.

    2017-05-01

    The impact of a stainless steel disk-shaped projectile launched by a single-stage light gas gun is used to generate planar shock waves with amplitudes on the order of 102MPa in a hydrogel target material. These shock waves are characterized using ultra-high-speed imaging as well as a fiber-optic probe hydrophone. Although the hydrogel equation of state (EOS) is unknown, the combination of these measurements with conservation of mass and momentum allows us to calculate pressure. It is also shown that although the hydrogel behaves similarly to water, the use of a water EOS underpredicts pressure amplitudes in the hydrogel by ˜10 % at the shock front. Further, the water EOS predicts pressures approximately 2% higher than those determined by conservation laws for a given value of the shock velocity. Shot to shot repeatability is controlled to within 10%, with the shock speed and pressure increasing as a function of the velocity of the projectile at impact. Thus the projectile velocity may be used as an adequate predictor of shock conditions in future work with a restricted suite of diagnostics.

  11. Synthesis, characterization and anti-bacterial activities of pure and Co-doped BaSO4 nanoparticles via chemical precipitation route.

    Science.gov (United States)

    Sivakumar, S; Soundhirarajan, P; Venkatesan, A; Khatiwada, Chandra Prasad

    2015-02-25

    In the present study, we reported that the synthesis and characterization of pure and diverse mole Co-doped BaSO4 nanoparticles have been synthesized by chemical precipitation technique. X-ray diffraction analysis (XRD) brought out the information about the synthesized products is orthorhombic structure and highly crystalline in nature. The average grain size of the samples was determined by using the Debye-Scherer's equation. The existence of functional groups and band area of the samples were confirmed by Fourier transform infrared (FTIR) spectroscopy. The direct and indirect band gap energy of pure and doped samples was carried out using UV-VIS-DRS. The surface micrograph, morphological distribution and elemental compositions of the synthesized products were assessed by scanning electron microscopy (SEM) and Energy dispersive X-ray (EDS). Thermo gravimetric and differential thermal analysis (TG-DTA) techniques were analyzed thermal behaviour of pure and Co-doped samples. Finally, antibacterial activities found the Gram-positive and Gram-negative bacteria are more active in transporter, dehydrogenize and periplasmic enzymatic activities of pure and doped samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Synthesis and Characterization of Phase-pure Copper Zinc Tin Sulfide (Cu2ZnSnS4) Nanoparticles

    Science.gov (United States)

    Monahan, Bradley Michael

    Semiconductor nanoparticles have been an important area of research in many different disciplines. A substantial amount of this work has been put toward advancing the field of photovoltaics. However, current p-type photovoltaic materials can not sustain the large scale production needed for future energy demands due to their low elemental abundance. Therefore, Earth abundant semiconductor materials have become of great interest to the photovoltaic community especially, the material copper zinc tin sulfide (CZTS), also known by its mineral name kesterite. CZTS exhibits desirable properties for photovoltaics, such as elemental abundance, high absorption coefficient (~104 cm-1 ), high carrier concentration, and optimum direct band gap (1.5 eV). To date, solution based approaches for making CZTS have yielded the most promising conversion efficiencies in solar cells. To that end, the motivation of nanoparticle based inks that can be used in high throughput production are an attractive route for large scale deployment. This has driven the need to make high quality CZTS nanoparticles that possess the properties of the pure kesterite phase with high monodispersity that can be deposited into dense thin films. The inherent challenge of making a quaternary compound of a single phase has made this a difficult task; however, some of those fundamental problems are addressed in this thesis. This had resulted in the synthesis of phase-pure k-CZTS confirmed by powder X-ray diffraction, Raman spectroscopy, UV-visible absorption spectroscopy and energy dispersive x-ray spectroscopy. Furthermore, ultra-fast laser spectroscopy was done on CZTS thin films made from phase-pure kesterite nanoparticles synthesized in this work. This thesis provides new data that directly probes the lifetime of photogenerated free carriers in kesterite CZTS (k-CZTS) thin films.

  13. Characterization of Axial Inducer Cavitation Instabilities via High Speed Video Recordings

    Science.gov (United States)

    Arellano, Patrick; Peneda, Marinelle; Ferguson, Thomas; Zoladz, Thomas

    2011-01-01

    Sub-scale water tests were undertaken to assess the viability of utilizing high resolution, high frame-rate digital video recordings of a liquid rocket engine turbopump axial inducer to characterize cavitation instabilities. These high speed video (HSV) images of various cavitation phenomena, including higher order cavitation, rotating cavitation, alternating blade cavitation, and asymmetric cavitation, as well as non-cavitating flows for comparison, were recorded from various orientations through an acrylic tunnel using one and two cameras at digital recording rates ranging from 6,000 to 15,700 frames per second. The physical characteristics of these cavitation forms, including the mechanisms that define the cavitation frequency, were identified. Additionally, these images showed how the cavitation forms changed and transitioned from one type (tip vortex) to another (sheet cavitation) as the inducer boundary conditions (inlet pressures) were changed. Image processing techniques were developed which tracked the formation and collapse of cavitating fluid in a specified target area, both in the temporal and frequency domains, in order to characterize the cavitation instability frequency. The accuracy of the analysis techniques was found to be very dependent on target size for higher order cavitation, but much less so for the other phenomena. Tunnel-mounted piezoelectric, dynamic pressure transducers were present throughout these tests and were used as references in correlating the results obtained by image processing. Results showed good agreement between image processing and dynamic pressure spectral data. The test set-up, test program, and test results including H-Q and suction performance, dynamic environment and cavitation characterization, and image processing techniques and results will be discussed.

  14. Characterization of Ge Doping on Sb_2Te_3 for High-Speed Phase Change Memory Application

    International Nuclear Information System (INIS)

    Zhu Yue-Qin; Xie Hua-Qing; Zhang Zhong-Hua; Song San-Nian; Song Zhi-Tang; Shen Lan-Lan; Li Le; Wu Liang-Cai; Liu Bo

    2015-01-01

    The phase change material of Ge-doped Sb_2Te_3 is shown to have higher crystallization temperature and better thermal stability compared with pure Sb_2Te_3. Ge_0_._1_1Sb_2Te_3 alloys are considered to be a potential candidate for phase change random access memories, as proved by a higher crystallization temperature, a better data retention ability, and a faster switching speed in comparison with those of Ge_2Sb_2Te_5. In addition, Ge_0_._1_1Sb_2Te_3 presents extremely rapid reverse switching speed (10 ns), and up to 10"5 programming cycles are obtained with stable set and reset resistances. (paper)

  15. Preparation and characterization of phase-pure anatase and rutile TiO2 powder by new chemistry route

    International Nuclear Information System (INIS)

    Pereira, E. A.; Montanhera, M.A.; Paula, F.R.; Spada, E.R.

    2014-01-01

    Titanium dioxide (TiO 2 ) is used in a wire range applications such as photocatalysis and sensor device. In this work is shown a new and effective method for the preparation of TiO 2 nanocrystalline in the crystallographic forms, anatase and rutile. The method involves dissolving the TiOSO 4 powder in H 2 O 2 solution and thermal treatment of amorphous precipitate. The technique of X-ray diffraction was used to follow the structure evolution of amorphous precipitate. Pure anatase structure and rutile are obtained at 600 deg C and 1000 deg C with a grain size estimated 24 and 55 nm respectively. TiO 2 nanoparticles is a promising alternative of the low cost whose potential for solar cells deserve a careful evaluation, especially in hybrid solar cells that employs TiO 2 as electron acceptor and as transport channels. (author)

  16. Synthesis and characterization of pure strontium apatite particles and nanoporous scaffold prepared by dextrose-templated method

    Science.gov (United States)

    Ma, Xiaoyu; Liu, Yongjia; Zhu, Bangshang

    2018-02-01

    Strontium shows an increasing interest on bone formation and bone resorption prevention. Here, pure apatite strontium (Ap-SrOH) [Sr5(PO4)3(OH), strontium hydroxyapatite] particles were prepared by the precipitation method using Sr(NO3)2 · 6H2O and (NH4)2HPO4 as reagents. Scanning electron microscope, transmission electron microscope combined with electron diffraction, X-ray diffraction, Fourier transform infrared spectra (FTIR), variable temperature FTIR and thermo gravimetric analysis were employed to evaluate the crystalline structure, chemical composition, and thermal stability of the Ap-SrOH particles. The results show that phase pure Ap-SrOH particles were prepared by wet precipitation. The obtained Ap-SrOH particles are single crystal in phase structure, they have hexagonal fusiform shape, and their size is about 30-180 nm in diameter, and 0.4-2.5 μm in length. The cell MTT assay evaluations indicate that Ap-SrOH particles have very low cytotoxicity. Furthermore, nanoporous Ap-SrOH scaffolds were synthesized by anhydrous dextrose template method. After mixed 5-10 wt% of anhydrous dextrose with Ap-SrOH particles, pressed into discs, and sintered in microwave muffle furnace at 600 °C, the scaffolds with both nanoporous and nanotopography were formed. Cell culture of MC3T3-E1 osteoblasts in vitro show cells grow well on nanoporous Ap-SrOH scaffold. Therefore, Ap-SrOH particles and their nanoporous scaffolds are promising biomaterials for bone repairing and bone disease (e.g. osteoporosis) healing.

  17. Morphological and microstructural characterization of nanostructured pure α-phase W coatings on a wide thickness range

    Energy Technology Data Exchange (ETDEWEB)

    Gordillo, N., E-mail: nuri.gordillo@gmail.com [Instituto de Fusión Nuclear, ETSI de Industriales, Universidad Politécnica de Madrid, C/José Gutierrez Abascal, 2, E-28006 Madrid (Spain); CEI Campus Moncloa, UCM-UPM, Madrid (Spain); Panizo-Laiz, M. [Instituto de Fusión Nuclear, ETSI de Industriales, Universidad Politécnica de Madrid, C/José Gutierrez Abascal, 2, E-28006 Madrid (Spain); Tejado, E. [Department of Materials Science, Research Centre on Safety and Durability of Structures and Materials (CISDEM), UPM-CSIC, C/Profesor Aranguren s/n, E-28040 Madrid (Spain); Centro Nacional de Investigaciones Metalúrgicas, CENIM-CSIC, Madrid (Spain); Fernandez-Martinez, I. [Instituto de Energía Solar (IES), Universidad Politécnica de Madrid, Avenida Complutense s/n, E-28040 Madrid (Spain); Instituto de Microelectrónica de Madrid, IMM-CNM-CSIC, Isaac Newton 8 PTM, Tres Cantos, E-28760 Madrid (Spain); Rivera, A. [Instituto de Fusión Nuclear, ETSI de Industriales, Universidad Politécnica de Madrid, C/José Gutierrez Abascal, 2, E-28006 Madrid (Spain); Pastor, J.Y. [Department of Materials Science, Research Centre on Safety and Durability of Structures and Materials (CISDEM), UPM-CSIC, C/Profesor Aranguren s/n, E-28040 Madrid (Spain); Castro, C. Gómez de [Departamento de Física de Materiales, Facultad de CC. Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, E-28040 Madrid (Spain); and others

    2014-10-15

    Highlights: • Pure α-phase tungsten nanostructures were deposited by DC-magnetron sputtering. • Non-delaminated coatings were achieved at powers ≤50 W. • The coating thicknesses vary from 30 nm up to ∼4.0 μm. • The influence of the substrate on the coating properties was investigated. • We report on the morphological, microstructural and mechanical properties. - Abstract: Nanostructured tungsten (nanoW) coatings have been deposited by DC magnetron sputtering. First, the influence of the sputtering power on the adhesion of the coatings to the substrate was investigated by depositing coatings at powers varying from 30 up to 220 W. Non-delaminated coatings were achieved at powers ≤50 W. Second, the influence of coating thickness on the morphological, microstructural and mechanical properties was investigated for films deposited at 50 W with thicknesses varying from 30 nm up to ∼4.0 μm. SEM images reveal that all the films are highly compact, consisting of nanometer sized columns that grow perpendicular to the substrate. XRD data evidence that films are monophasic, being made of pure α-phase. All coatings show compressive stress and low micro-strain. Nanoindentation tests show that coatings have a hardness higher than that reported for coarse grained W. No significant dependence of the previous properties on coating thickness was observed. Finally, the influence of the substrate on coatings properties was studied, by depositing a W coating at a power of 50 W on a commercial steel substrate: no significant dependence was found.

  18. GPS-Based Highway Performance Monitoring Performance Monitoring Using GPS: Characterization of Travel Speeds on any Roadway Segment

    OpenAIRE

    Kornhauser, Alain L.

    2012-01-01

    Presented is a characterization of travel speed on any roadway segment based on probe vehicle position data. Most of the characterization is based position data obtained from GPS receivers because of their high precision and their increasing availability. Comparison is also made to Qualcomm’s Automatic Satellite Position Reporting (QASPR) system because of its long history (10+ years) of extensive use by the long-haul trucking industry. Described is the use of these data in conjunction with d...

  19. Characterizations of diverse mole of pure and Ni-doped α-Fe2O3 synthesized nanoparticles through chemical precipitation route.

    Science.gov (United States)

    Sivakumar, S; Anusuya, D; Khatiwada, Chandra Prasad; Sivasubramanian, J; Venkatesan, A; Soundhirarajan, P

    2014-07-15

    In the present study, an attempt has been made for characterization and synthesis of pure and Ni-doped α-Fe2O3 (hematite) nanoparticles by chemical precipitation method. The synthesized products have been studied by X-ray diffraction (X-RD), Fourier transform infrared (FTIR) spectroscopy, UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM) techniques. The estimated average diameter of α-Fe2O3 nanoparticles were calculated by using the Debye-Scherrer equation and established as 31 nm. SEM micrographs showed the surface morphology as well as structures and particles distributions of synthesized samples. The UV-Vis DRS showed the indirect and direct band gap energies of pure and Ni-doped α-Fe2O3, these were reduced from 1.9847 to 1.52 eV and 2.0503 to 1.76 eV respectively. This result suggested the dopant enhanced the semiconducting behavior of iron oxide nanoparticles to an extent proportional to its nickel doped in the α-Fe2O3. Further, the magnetic properties of the pure and doped samples were investigated by vibrating sample magnetometer (VSM) and evaluated the information of pure and doped samples exhibited saturated hysteresis loop at room temperature, which is indicating that the weak ferromagnetism in nature of our synthesized samples. In addition, it has been found from the magnetization hysteresis curves of Ni-doping, resulting from increased the saturation of magnetization and reduced the coercivity of used samples. Therefore, the present study showed the reduction in band gap energies and coercive field for α-Fe2O3 nanoparticles due to nickel doped. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Pure energy solutions - pure tomorrows

    International Nuclear Information System (INIS)

    Allison, J.

    2006-01-01

    HTC is an energy technology company whose mandate is to deliver 'Carbon Clear Solutions' to address the pending challenges the energy sector is facing in meeting the environmental impact of Greenhouse Gas emissions, and energy security. HTC will speak on its comprehensive suite of technologies including hydrogen production, CO 2 capture and CO 2 sequestration. HTC has patented technologies that produce H 2 from a broad variety of feedstocks such as Natural gas, Diesel, Gasoline, Bio-fuels i.e. ethanol, methanol and Coal Gasification. HTC Hydrogen reformation systems are unique in their method of delivering pure Hydrogen. Dry Reformation Reactor - New catalyst system designed to eliminate contamination problems (i.e. coking) while at the same time operate at a low temperature. Water Gas Shift Reactor - Plus - improved and redesigned catalyst that improves operating temperature and hydrogen production efficiency. Two stage catalyst reactor that provides near balance of the endothermic and exothermic reaction temperatures for efficient energy balance

  1. Characterization of the viscoelastic behavior of the pure bitumen grades 10/20 and 35/50 with macroindentation and finite element computation

    KAUST Repository

    Hamzaoui, Rabah

    2013-06-23

    In this article, we present an identification procedure that allows the determination of the viscoelasticity behavior of different grades of pure bitumen (bitumen 35/50 and bitumen 10/20). The procedure required in the first stage a mechanical response based on macroindentation experiments with a cylindrical indenter. A finite element simulation was performed in the second stage to compute the mechanical response corresponding to a viscoelasticity model described by three mechanical parameters. The comparison between the experimental and numerical responses showed a perfect matching. In addition, the identification procedure helped to discriminate between different bitumens characterized by different asphaltene and maltene contents. Finally, the developed procedure could be used as an efficient tool to characterize the mechanical behavior of the viscoelastic materials, thanks to the quantified relationship between the viscoleastic parameters and the force-penetration response. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3440-3450, 2013 Copyright © 2013 Wiley Periodicals, Inc.

  2. Antagonistic Mono- and Bi-Articular Lower-Limb Muscle Activities’ Model Characterization at Different Speeds

    Directory of Open Access Journals (Sweden)

    Dzahir M.A.M

    2017-01-01

    Full Text Available Nowadays, medical rehabilitation system has become a requirement due to increment in national rehabilitation centres and medical hospitals. An assistive rehabilitation orthosis becomes essential and was used for rehabilitation therapy, condition monitoring, and physical strengthening. This study focused on the lower limb assistive rehabilitation orthosis development using pneumatic artificial muscle. To successfully control this orthosis system which consists of antagonistic mono- and biarticular muscle actuators, it is necessary to construct a reliable control algorithm. The suitable control scheme and strategy to manoeuvre this orthosis system similar to human musculoskeletal system have yet to be fully developed and established. Based on the review study, it is said that the co-contraction controls of anterior-posterior pneumatic muscles was able to improve the joint stiffness and stability of the orthosis as well as good manoeuvrability. Therefore, a characterization model of an antagonistic mono- and bi-articular muscles activities of human's lowerlimb during walking motion will be necessary. A healthy young male subject was used as test subject to obtain the sEMG muscle activities for antagonistic mono- and bi-articular muscles (i.e., Vastus Medialis-VM, Vastus Lateralis-VL, Rectus Femoris-RF, and Bicep Femoris-BF. The tests were carried out at different speeds of 2km/h, 3km/h, and 4km/h for one minute walking motion on a treadmill. Then, the patterns of the sEMG muscle activities were modelled and characterised using fifth order polynomial equation. Based on the results, it is shown that the anterior and posterior muscles were exhibited a muscle synergy in-between multiple anterior or posterior muscles and muscle co-contraction between anteriorposterior muscles in order to control the movements at the joints during walking motion. As conclusion, it is proven that the sEMG muscle activities of the antagonistic mono- and bi

  3. Thin film deposition and characterization of pure and iron-doped electron-beam evaporated tungsten oxide for gas sensors

    Energy Technology Data Exchange (ETDEWEB)

    Tesfamichael, Tuquabo, E-mail: t.tesfamichael@qut.edu.a [Faculty of Built Environment and Engineering, School of Engineering Systems, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000 (Australia); Arita, Masashi [Graduate School of Information Science and Technology, Hokkaido University, Kita-14, Nishi-9, Kita-ku, Sapporo, 060-0814 (Japan); Bostrom, Thor [Faculty of Science and Technology, School of Physical and Chemical Sciences, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000 (Australia); Bell, John [Centre for Built Environment and Engineering Research, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000 (Australia)

    2010-06-30

    Pure tungsten oxide (WO{sub 3}) and iron-doped (10 at.%) tungsten oxide (WO{sub 3}:Fe) nanostructured thin films were prepared using a dual crucible Electron Beam Evaporation (EBE) technique. The films were deposited at room temperature under high vacuum onto glass as well as alumina substrates and post-heat treated at 300 {sup o}C for 1 h. Using Raman spectroscopy the as-deposited WO{sub 3} and WO{sub 3}:Fe films were found to be amorphous, however their crystallinity increased after annealing. The estimated surface roughness of the films was similar (of the order of 3 nm) to that determined using Atomic Force Microscopy (AFM). As observed by AFM, the WO{sub 3}:Fe film appeared to have a more compact surface as compared to the more porous WO{sub 3} film. X-ray photoelectron spectroscopy analysis showed that the elemental stoichiometry of the tungsten oxide films was consistent with WO{sub 3}. A slight difference in optical band gap energies was found between the as-deposited WO{sub 3} (3.22 eV) and WO{sub 3}:Fe (3.12 eV) films. The differences in the band gap energies of the annealed films were significantly higher, having values of 3.12 eV and 2.61 eV for the WO{sub 3} and WO{sub 3}:Fe films respectively. The heat treated films were investigated for gas sensing applications using noise spectroscopy. It was found that doping of Fe to WO{sub 3} produced gas selectivity but a reduced gas sensitivity as compared to the WO{sub 3} sensor.

  4. Characterization of the polymer energy landscape in polymer:fullerene bulk heterojunctions with pure and mixed phases

    KAUST Repository

    Sweetnam, Sean

    2014-10-08

    Theoretical and experimental studies suggest that energetic offsets between the charge transport energy levels in different morphological phases of polymer:fullerene bulk heterojunctions may improve charge separation and reduce recombination in polymer solar cells (PSCs). In this work, we use cyclic voltammetry, UV-vis absorption, and ultraviolet photoelectron spectroscopy to characterize hole energy levels in the polymer phases of polymer:fullerene bulk heterojunctions. We observe an energetic offset of up to 150 meV between amorphous and crystalline polymer due to bandgap widening associated primarily with changes in polymer conjugation length. We also observe an energetic offset of up to 350 meV associated with polymer:fullerene intermolecular interactions. The first effect has been widely observed, but the second effect is not always considered despite being larger in magnitude for some systems. These energy level shifts may play a major role in PSC performance and must be thoroughly characterized for a complete understanding of PSC function.

  5. High speed diagnostics for characterization of oxygen / hydrogen rocket injector flowfields

    Science.gov (United States)

    Locke, Justin M.

    Temporally-resolved diagnostics are needed to characterize the highly-turbulent flowfields of rocket engine combustors. Two different high speed diagnostic techniques have been applied successfully to study the combustion and mixing characteristics of single-element shear-coaxial injector flowfield in a rocket combustor. Tunable diode laser absorption spectroscopy (TDLAS) is applied to make in-situ measurements with combusting gas-gas propellants, and high speed imaging incorporating backlighting is applied to combusting and non-combusting liquid-gas and gas-gas propellants. Tunable diode laser absorption spectroscopy has been used to make path-integrated temperature and H2O mole fraction measurements in a gaseous oxygen / gaseous hydrogen uni-element rocket chamber with hot background flow. Four mixture conditions were studied at a nominal chamber pressure of 115 psia. Near infrared diode lasers were utilized to target rovibrational transitions of water vapor, which is created through the combustion processes. Both direct absorption spectroscopy and wavelength modulation spectroscopy with second harmonic normalized by first harmonic (1f-normalized WMS-2 f) techniques were applied, with the harmonic detection technique found to yield the best results. Centerline measurements were made at two axial locations, in the near-injector region and far-field region further downstream. Time-resolved measurements of temperature and H2O mole fraction in the rocket chamber are presented. The TDLAS measurements shows clear differences between the near-injector and downstream measurement locations. Mean path-integrated temperatures and H2O mole fractions in the near-injector region are lower than the downstream measurement location. Fluctuations in path-integrated temperature and H2O mole fraction in the downstream location are significantly greater than the near-injector region. This suggests increased turbulence and larger-scale mixing processes are occurring in the downstream

  6. Synthesis and Characterization of Pure and Al Modified BaSnO3 Thick Film Resistor and Studies of its Gas Sensing Performance

    Directory of Open Access Journals (Sweden)

    N. U. PATIL

    2013-02-01

    Full Text Available In this work we report the synthesis, microstructure, electric properties and sensing performance of BaSnO3 (BS powder, it was prepared by solid state mechano-chemical method. As prepared powder is calcinated at temperatures 1000 °C and 1200 °C and tested for crystallization. Thick films were prepared using simple yet effective screen-printing technology. Structural and electrical analyses were performed and the results have been correlated. The pure BS film shows good response (S=9.8 to NH3 at elevated temperature up to 500 °C along with response other gases with lower sensitivity such as CO2, CO, H2S for various gas concentrations, when the pure film is surface modified with Al2O3, film improves the selectivity and sensitivity. Maximum response (S=21.2 was found to H2S gas at temperature of 300 °C for gas concentration as low as up to 100 ppm. The characterization of the films was done by XRD, SEM and TGA. Crystallite size, surface area, electric properties and gas sensitivity of the films were measured and presented.

  7. Synthesis and characterization of pure and Li⁺ activated Alq₃ complexes for green and blue organic light emitting diodes and display devices.

    Science.gov (United States)

    Bhagat, S A; Borghate, S V; Kalyani, N Thejo; Dhoble, S J

    2014-08-01

    Pure and Li(+)-doped Alq3 complexes were synthesized by simple precipitation method at room temperature, maintaining the stoichiometric ratio. These complexes were characterized by X-ray diffraction, ultraviolet-visible absorption and Fourier transform infrared and photoluminescence (PL) spectra. X-ray diffraction analysis reveals the crystalline nature of the synthesized complexes, while Fourier transform infrared spectroscopy confirm the molecular structure, the completion of quinoline ring formation and presence of quinoline structure in the metal complex. Ultraviolet-visible and PL spectra revealed that Li(+) activated Alq3 complexes exhibit the highest intensity in comparison to pure Alq3 phosphor. Thus, Li(+) enhances PL emission intensity when doped into Alq3 phosphor. The excitation spectra lie in the range of 383-456 nm. All the synthesized complexes other than Liq give green emission, while Liq gives blue emission with enhanced intensity. Thus, he synthesized phosphors are the best suitable candidates for green- and blue-emitting organic light emitting diode, PL liquid-crystal display and solid-state lighting applications. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Spectral characterization of the fluorescent components present in humic substances, fulvic acid and humic acid mixed with pure benzo(a)pyrene solution

    Science.gov (United States)

    El Fallah, Rawa; Rouillon, Régis; Vouvé, Florence

    2018-06-01

    The fate of benzo(a)pyrene (BaP), a ubiquitous contaminant reported to be persistent in the environment, is largely controlled by its interactions with the soil organic matter. In the present study, the spectral characteristics of fluorophores present in the physical fractions of the soil organic matter were investigated in the presence of pure BaP solution. After extraction of humic substances (HSs), and their fractionation into fluvic acid (FA) and humic acid (HA), two fluorescent compounds (C1 and C2) were identified and characterized in each physical soil fraction, by means of fluorescence excitation-emission matrices (FEEMs) and Parallel Factor Analysis (PARAFAC). Then, to each type of fraction having similar DOC content, was added an increasing volume of pure BaP solution in attempt to assess the behavior of BaP with the fluorophores present in each one. The application of FEEMs-PARAFAC method validated a three-component model that consisted of the two resulted fluorophores from HSs, FA and HA (C1 and C2) and a BaP-like fluorophore (C3). Spectral modifications were noted for components C2HSs (C2 in humic substances fraction) (λex/λem: 420/490-520 nm), C2FA (C2 in fulvic acid fraction) (λex/λem: 400/487(517) nm) and C1HA (C1 in humic acid fraction) (λex/λem: 350/452(520) nm). We explored the impact of increasing the volume of the added pure BaP solution on the scores of the fluorophores present in the soil fractions. It was found that the scores of C2HSs, C2FA, and C1HA increased when the volume of the added pure BaP solution increased. Superposition of the excitation spectra of these fluorophores with the emission spectrum of BaP showed significant overlaps that might explain the observed interactions between BaP and the fluorescent compounds present in SOM physical fractions.

  9. Characterization of Tool Wear in High-Speed Milling of Hardened Powder Metallurgical Steels

    Directory of Open Access Journals (Sweden)

    Fritz Klocke

    2011-01-01

    Full Text Available In this experimental study, the cutting performance of ball-end mills in high-speed dry-hard milling of powder metallurgical steels was investigated. The cutting performance of the milling tools was mainly evaluated in terms of cutting length, tool wear, and cutting forces. Two different types of hardened steels were machined, the cold working steel HS 4-2-4 PM (K490 Microclean/66 HRC and the high speed steel HS 6-5-3 PM (S790 Microclean/64 HRC. The milling tests were performed at effective cutting speeds of 225, 300, and 400 m/min with a four fluted solid carbide ball-end mill (0 = 6, TiAlN coating. It was observed that by means of analytically optimised chipping parameters and increased cutting speed, the tool life can be drastically enhanced. Further, in machining the harder material HS 4-2-4 PM, the tool life is up to three times in regard to the less harder material HS 6-5-3 PM. Thus, it can be assumed that not only the hardness of the material to be machined plays a vital role for the high-speed dry-hard cutting performance, but also the microstructure and thermal characteristics of the investigated powder metallurgical steels in their hardened state.

  10. Phenotypic characterization of speed-associated gait changes in mice reveals modular organization of locomotor networks

    DEFF Research Database (Denmark)

    Bellardita, Carmelo; Kiehn, Ole

    2015-01-01

    behavioral outcomes expressed at different speeds of locomotion. Here, we use detailed kinematic analyses to search for signatures of a modular organization of locomotor circuits in intact and genetically modified mice moving at different speeds of locomotion. We show that wild-type mice display three...... distinct gaits: two alternating, walk and trot, and one synchronous, bound. Each gait is expressed in distinct ranges of speed with phenotypic inter-limb and intra-limb coordination. A fourth gait, gallop, closely resembled bound in most of the locomotor parameters but expressed diverse inter......-limb coordination. Genetic ablation of commissural V0V neurons completely removed the expression of one alternating gait, trot, but left intact walk, gallop, and bound. Ablation of commissural V0V and V0D neurons led to a loss of walk, trot, and gallop, leaving bound as the default gait. Our study provides...

  11. Characterization of Diamond Nanoparticles by High-Speed Micro-Thermal Field-Flow Fractionation

    Czech Academy of Sciences Publication Activity Database

    Janča, Josef

    2015-01-01

    Roč. 20, č. 8 (2015), s. 671-680 ISSN 1023-666X R&D Projects: GA MŠk(CZ) LO1212 Institutional support: RVO:68081731 Keywords : diamond nanoparticles * high-speed microfluidic separation * micro-thermal field-flow fractionation, * article size distribution Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.515, year: 2015

  12. Flow and free running speed characterization of dental air turbine handpieces.

    Science.gov (United States)

    Dyson, J E; Darvell, B W

    1999-09-01

    Dental air turbine handpieces have been widely used in clinical dentistry for over 30 years, yet little work has been reported on their performance. A few studies have been concerned with measurement of speed (i.e. rotation rate), torque and power performance of these devices, but neither investigations of functional relationships between controlling variables nor theory dealing specifically with this class of turbine have been reported. This has hindered the development of satisfactory methods of handpiece specification and of testing dental rotary cutting tools. It was the intention of the present work to remedy that deficiency. Measurements of pressure, temperature, gas flow rate and rotation rate were made with improved accuracy and precision for 14 ball bearing turbine handpieces on several gases. Functional relationships between gas properties, supply pressure, flow rate, turbine design factors and free running speed were identified and equations describing these aspects of behaviour of this class of turbine developed. The rotor radius, through peripheral Mach number, was found to be a major determinant of speed performance. In addition, gas flow was found to be an important limiting factor through the effect of choke. Each dental handpiece can be treated as a simple orifice of a characteristic cross-sectional area. Free running speed can be explained in terms of gas properties and pressure, with allowance for a design-specific performance coefficient.

  13. Functional characterization of salt-tolerant microbial esterase WDEst17 and its use in the generation of optically pure ethyl (R)-3-hydroxybutyrate.

    Science.gov (United States)

    Wang, Yilong; Xu, Yongkai; Zhang, Yun; Sun, Aijun; Hu, Yunfeng

    2018-06-01

    The two enantiomers of ethyl 3-hydroxybutyrate are important intermediates for the synthesis of a great variety of valuable chiral drugs. The preparation of chiral drug intermediates through kinetic resolution reactions catalyzed by esterases/lipases has been demonstrated to be an efficient and environmentally friendly method. We previously functionally characterized microbial esterase PHE21 and used PHE21 as a biocatalyst to generate optically pure ethyl (S)-3-hydroxybutyrate. Herein, we also functionally characterized one novel salt-tolerant microbial esterase WDEst17 from the genome of Dactylosporangium aurantiacum subsp. Hamdenensis NRRL 18085. Esterase WDEst17 was further developed as an efficient biocatalyst to generate (R)-3-hydroxybutyrate, an important chiral drug intermediate, with the enantiomeric excess being 99% and the conversion rate being 65.05%, respectively, after process optimization. Notably, the enantio-selectivity of esterase WDEst17 was opposite than that of esterase PHE21. The identification of esterases WDEst17 and PHE21 through genome mining of microorganisms provides useful biocatalysts for the preparation of valuable chiral drug intermediates. © 2018 Wiley Periodicals, Inc.

  14. Dynamic Characterizations of an 8-frame, Half-Strip, High-speed X-ray Microchannel Plate Imager

    International Nuclear Information System (INIS)

    Ken Moy; Ming Wu; Craig Kruschwitz; Aric Tibbits; Matt Griffin; Greg Rochau

    2008-01-01

    High-speed microchannel plate (MCP)-based imagers are critical detectors for x-ray diagnostics employed on Z-experiments at Sandia National Laboratories (SNL) to measure time-resolved x-ray spectra and to image dynamic hohlraums. A multiframe design using eight half strips in one imager permits recordings of radiation events in discrete temporal snapshots to yield a time-evolved movie. We present data using various facilities to characterize the performance of this design. These characterization studies include DC and pulsed-voltage biased measurements in both saturated and linear operational regimes using an intense, short-pulsed UV laser. Electrical probe measurements taken to characterize the shape of the HV pulse propagating across the strips help to corroborate the spatial gain dependence

  15. Design and characterization of high-speed CMOS pseudo-LVDS transceivers

    International Nuclear Information System (INIS)

    Kondratenko, S V

    2016-01-01

    High-speed transceiver for on-board systems of data collection and processing need to meet additional requirements, such as low power consumption and increased radiation hardness. It is therefore necessary to compare and search for alternative variants of transceivers on the physical layer, where high transfer speed is not achieved at the cost of a significant increase in power consumption or a limitation of transmission distance by the size of a printed circuit board. For on-board applications, it is also necessary to solve the problem of increasing the radiation hardness without going to expensive types of technology. In this paper, we studied some variants of implementation of pseudo-LVDS transceivers and analyzed their achievable quantitative characteristics. According to the results of calculations and analysis of the literature, specialized transceivers of this type, intended for the manufacture or manufactured according to the bulk CMOS technology processes in the range of 250-80 nm, can provide data speeds up to 6 Gbps at a specific power consumption of less than 4 mW/Gbps. (paper)

  16. Design and characterization of high-speed CMOS pseudo-LVDS transceivers

    Science.gov (United States)

    Kondratenko, S. V.

    2016-02-01

    High-speed transceiver for on-board systems of data collection and processing need to meet additional requirements, such as low power consumption and increased radiation hardness. It is therefore necessary to compare and search for alternative variants of transceivers on the physical layer, where high transfer speed is not achieved at the cost of a significant increase in power consumption or a limitation of transmission distance by the size of a printed circuit board. For on-board applications, it is also necessary to solve the problem of increasing the radiation hardness without going to expensive types of technology. In this paper, we studied some variants of implementation of pseudo-LVDS transceivers and analyzed their achievable quantitative characteristics. According to the results of calculations and analysis of the literature, specialized transceivers of this type, intended for the manufacture or manufactured according to the bulk CMOS technology processes in the range of 250-80 nm, can provide data speeds up to 6 Gbps at a specific power consumption of less than 4 mW/Gbps.

  17. Ultrasound Characterization of Microbead and Cell Suspensions by Speed of Sound Measurements of Neutrally Buoyant Samples

    DEFF Research Database (Denmark)

    Cushing, Kevin W.; Garofalo, Fabio; Magnusson, Cecilia

    2017-01-01

    . The density of the microparticles is determined by using a neutrally buoyant selection process that involves centrifuging of microparticles suspended in different density solutions, CsCl for microbeads and Percoll for cells. The speed of sound at 3 MHz in the neutrally buoyant suspensions is measured...... and fixed cells, such as red blood cells, white blood cells, DU-145 prostate cancer cells, MCF-7 breast cancer cells, and LU-HNSCC-25 head and-neck squamous carcinoma cells in phosphate buffered saline. The results show agreement with published data obtained by other methods....

  18. Sonochemical synthesis and characterization of nano-sized zinc(II coordination complex as a precursor for the preparation of pure-phase zinc(II oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Maryam Ranjbar

    2017-01-01

    Full Text Available In current study, nanoparticles and single crystals of a Zn(II coordination complex, [Zn(dmphI2](1, {dmph=2,9-dimethyl-1,10-phenanthroline(neocuproine}, have been synthesized by the reaction of zinc(II acetate, KI and neocuproine as ligand in methanol using sonochemical and heat gradient methods, respectively. The nanostructure of 1 was characterized by scanning electron microscopy (SEM, X-ray powder diffraction (XRD, FT-IR spectroscopy and elemental analyses, and the structure of compound 1 was determined by single-crystal X-ray diffraction. The thermal stability of nano-sized 1 has been studied by thermogravimetric (TG and differential thermal analyses (DTA. Structural determination of compound 1 reveals the Zn(II ion is four-coordinated in a distorted tetrahedral configuration by two N atoms from a 2,9-dimethyl-1,10-Phenanthroline ligand and two terminal I atoms. The effect of supercritical condition on stability, size and morphology of nano-structured compound 1 has also been studied. The XRD pattern of the residue obtained from thermal decomposition of nano-sized compound 1 at 600 °C under air atmosphere provided pure phase of ZnO with the average particles size of about 31 nm.

  19. Isolation, pure culture and characterization of Serratia symbiotica sp. nov., the R-type of secondary endosymbiont of the black bean aphid Aphis fabae.

    Science.gov (United States)

    Sabri, Ahmed; Leroy, Pascal; Haubruge, Eric; Hance, Thierry; Frère, Isabelle; Destain, Jacqueline; Thonart, Philippe

    2011-09-01

    An intracellular symbiotic bacterium was isolated from the flora of a natural clone of the black bean aphid Aphis fabae. The strain was able to grow freely in aerobic conditions on a rich medium containing 1 % of each of the following substrates: glucose, yeast extract and casein peptone. Pure culture was achieved through the use of solid-phase culture on the same medium and the strain was designated CWBI-2.3(T). 16S rRNA gene sequence analysis revealed that strain CWBI-2.3(T) was a member of the class Gammaproteobacteria, having high sequence similarity (>99 %) with 'Candidatus Serratia symbiotica', the R-type of secondary endosymbiont that is found in several aphid species. As strain CWBI-2.3(T) ( = LMG 25624(T) = DSM 23270(T)) was the first R-type symbiont to be isolated and characterized, it was designated as the type strain of Serratia symbiotica sp. nov.

  20. Synthesis, characterization and anti-microbial activity of pure, Cu2+ and Cd2+ doped organic NLO l-arginine trifluoroacetate single crystals

    Science.gov (United States)

    Prasanyaa, T.; Haris, M.; Jayaramakrishnan, V.; Amgalan, M.; Mathivanan, V.

    2013-10-01

    Optically transparent Cu2+ and Cd2+ doped l-arginine trifluoroacetate (LATF) single crystals were grown from its aqueous solution using the slow solvent evaporation technique. The grown crystals were characterized by powder x-ray diffraction to confirm the monoclinic crystal structure. The percentage of transmittance measured using the ultraviolet-visible-near infrared spectrophotometer was found to be more than 80% for doped crystals. The functional group analysis of the grown crystals has been made by Fourier transform infrared spectroscopy. Thermogravimetric/differential thermal analysis was performed for the grown crystals. An atomic absorption study was carried out to determine the presence of Cu2+ and Cd2+. The hardness of the grown crystals was assessed and the results show a significant variation in the hardness value between the pure and doped LATF crystals. The second harmonic generation measurements show that Cu2+ doped LATF is 2.8 times greater and Cd2+ doped is 2.6 times greater than KDP. The anti-bacterial and anti-fungal activities of the title compound were performed using the disc diffusion method against standard bacteria Escherichia coli, Xanthomonas oryzae and against the fungus Aspergillus niger and Aspergillus flavus.

  1. Synthesis, characterization and anti-microbial activity of pure, Cu2+ and Cd2+ doped organic NLO l-arginine trifluoroacetate single crystals

    International Nuclear Information System (INIS)

    Prasanyaa, T; Haris, M; Amgalan, M; Mathivanan, V; Jayaramakrishnan, V

    2013-01-01

    Optically transparent Cu 2+ and Cd 2+ doped l-arginine trifluoroacetate (LATF) single crystals were grown from its aqueous solution using the slow solvent evaporation technique. The grown crystals were characterized by powder x-ray diffraction to confirm the monoclinic crystal structure. The percentage of transmittance measured using the ultraviolet–visible–near infrared spectrophotometer was found to be more than 80% for doped crystals. The functional group analysis of the grown crystals has been made by Fourier transform infrared spectroscopy. Thermogravimetric/differential thermal analysis was performed for the grown crystals. An atomic absorption study was carried out to determine the presence of Cu 2+ and Cd 2+ . The hardness of the grown crystals was assessed and the results show a significant variation in the hardness value between the pure and doped LATF crystals. The second harmonic generation measurements show that Cu 2+ doped LATF is 2.8 times greater and Cd 2+ doped is 2.6 times greater than KDP. The anti-bacterial and anti-fungal activities of the title compound were performed using the disc diffusion method against standard bacteria Escherichia coli, Xanthomonas oryzae and against the fungus Aspergillus niger and Aspergillus flavus. (paper)

  2. Channel characterization for high-speed W-band wireless communication links

    DEFF Research Database (Denmark)

    Rommel, Simon; Cavalcante, Lucas Costa Pereira; Vegas Olmos, Juan José

    2015-01-01

    We present and discuss results from an experimental characterization of the W-band indoor wireless channel, including both large and small scale fading phenomena as well as corresponding channel parameters and their impact on system performance....

  3. Microstructural characterization of WC-TiC-Co cutting tools during high-speed machining of P20 mold steel

    International Nuclear Information System (INIS)

    Farhat, Z.N.

    2003-01-01

    The wear behavior of tungsten carbide (WC)-TiC-Co cutting tools during cutting P20 tool steel was investigated. Orthogonal cutting tests were performed on a CNC lathe using five speeds, namely, 60, 120, 240, 380 and 600 m/min. Wear, as the width of the wear land, was monitored at five time intervals. Wear characterization of the rake and the flank surfaces as well as the collected chips was performed using scanning electron microscopy (SEM), backscattered electron imaging and energy-dispersive X-ray analysis (EDX). Microhardness of collected chips was also performed to monitor strain hardening effects during cutting. Two dominant wear mechanisms were identified: at high speed (380-600 m/min), wear was found to occur by a melt wear mechanism; at low speed (60-120 m/min), adhesion (built-up edge) followed by delamination was found to be the cause of wear damage. It was also found that deformation in the chips occurred by localized shear deformation

  4. High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy

    International Nuclear Information System (INIS)

    Hihath, Sahar; Santala, Melissa K.; Campbell, Geoffrey; Benthem, Klaus van

    2016-01-01

    The dewetting of thin films can occur in either the solid or the liquid state for which different mass transport mechanisms are expected to control morphological changes. Traditionally, dewetting dynamics have been examined on time scales between several seconds to hours, and length scales ranging between nanometers and millimeters. The determination of mass transport mechanisms on the nanoscale, however, requires nanoscale spatial resolution and much shorter time scales. This study reports the high-speed observation of dewetting phenomena for kinetically constrained Ni thin films on crystalline SrTiO_3 substrates. Movie-mode Dynamic Transmission Electron Microscopy (DTEM) was used for high-speed image acquisition during thin film dewetting at different temperatures. DTEM imaging confirmed that the initial stages of film agglomeration include edge retraction, hole formation, and growth. Finite element modeling was used to simulate temperature distributions within the DTEM samples after laser irradiation with different energies. For pulsed laser irradiation at 18 μJ, experimentally observed hole growth suggests that Marangoni flow dominates hole formation in the liquid nickel film. After irradiation with 13.8 μJ, however, the observations suggest that dewetting was initiated by nucleation of voids followed by hole growth through solid-state surface diffusion.

  5. High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hihath, Sahar [Department of Materials Science and Engineering, University of California, Davis, 1 Shields Ave., Davis, California 95616 (United States); Department of Physics, University of California, Davis, 1 Shields Ave., Davis, California 95616 (United States); Santala, Melissa K.; Campbell, Geoffrey [Materials Science Division, Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States); Benthem, Klaus van, E-mail: benthem@ucdavis.edu [Department of Materials Science and Engineering, University of California, Davis, 1 Shields Ave., Davis, California 95616 (United States)

    2016-08-28

    The dewetting of thin films can occur in either the solid or the liquid state for which different mass transport mechanisms are expected to control morphological changes. Traditionally, dewetting dynamics have been examined on time scales between several seconds to hours, and length scales ranging between nanometers and millimeters. The determination of mass transport mechanisms on the nanoscale, however, requires nanoscale spatial resolution and much shorter time scales. This study reports the high-speed observation of dewetting phenomena for kinetically constrained Ni thin films on crystalline SrTiO{sub 3} substrates. Movie-mode Dynamic Transmission Electron Microscopy (DTEM) was used for high-speed image acquisition during thin film dewetting at different temperatures. DTEM imaging confirmed that the initial stages of film agglomeration include edge retraction, hole formation, and growth. Finite element modeling was used to simulate temperature distributions within the DTEM samples after laser irradiation with different energies. For pulsed laser irradiation at 18 μJ, experimentally observed hole growth suggests that Marangoni flow dominates hole formation in the liquid nickel film. After irradiation with 13.8 μJ, however, the observations suggest that dewetting was initiated by nucleation of voids followed by hole growth through solid-state surface diffusion.

  6. Development and characterization of high-frequency resonance-enhanced microjet actuators for control of high-speed jets

    Science.gov (United States)

    Upadhyay, Puja; Gustavsson, Jonas P. R.; Alvi, Farrukh S.

    2016-05-01

    For flow control applications requiring high-frequency excitation, very few actuators have sufficient dynamic response and/or control authority to be useful in high-speed flows. Due to this reason, experiments involving high-frequency excitation, attempted in the past, have been limited to either low-frequency actuation with reasonable control authority or moderate-frequency actuation with limited control authority. The current work expands on the previous development of the resonance-enhanced microactuators to design actuators that are capable of producing high-amplitude pulses at much higher frequencies [{O} (10 kHz)]. Using lumped element modeling, two actuators have been designed with nominal frequencies of 20 and 50 kHz. Extensive benchtop characterization using acoustic measurements as well as optical diagnostics using a high-resolution micro-schlieren setup is employed to characterize the dynamic response of these actuators. The actuators performed at a range of frequencies, 20.3-27.8 and 54.8-78.2 kHz, respectively. In addition to providing information on the actuator flow physics and performance at various operating conditions, this study serves to develop easy-to-integrate high-frequency actuators for active control of high-speed jets. Preliminary testing of these actuators is performed by implementing the 20-kHz actuator on a Mach 0.9 free jet flow field for noise reduction. Acoustic measurements in the jet near field demonstrate attenuation of radiated noise at all observation angles.

  7. Rehabilitation of pure alexia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Ólafsdóttir, Rannveig Rós; Arendt, Ida-Marie

    2013-01-01

    that pure alexia was an easy target for rehabilitation efforts. We review the literature on rehabilitation of pure alexia from 1990 to the present, and find that patients differ widely on several dimensions like alexia severity, and associated deficits. Many patients reported to have pure alexia......-designed and controlled studies of rehabilitation of pure alexia....

  8. Characterization of a Laser-Generated Perturbation in High-Speed Flow for Receptivity Studies

    Science.gov (United States)

    Chou, Amanda; Schneider, Steven P.; Kegerise, Michael A.

    2014-01-01

    A better understanding of receptivity can contribute to the development of an amplitude-based method of transition prediction. This type of prediction model would incorporate more physics than the semi-empirical methods, which are widely used. The experimental study of receptivity requires a characterization of the external disturbances and a study of their effect on the boundary layer instabilities. Characterization measurements for a laser-generated perturbation were made in two different wind tunnels. These measurements were made with hot-wire probes, optical techniques, and pressure transducer probes. Existing methods all have their limitations, so better measurements will require the development of new instrumentation. Nevertheless, the freestream laser-generated perturbation has been shown to be about 6 mm in diameter at a static density of about 0.045 kg/cubic m. The amplitude of the perturbation is large, which may be unsuitable for the study of linear growth.

  9. Semi-automatic characterization and simulation of VCSEL devices for high speed VSR communications

    Science.gov (United States)

    Pellevrault, S.; Toffano, Z.; Destrez, A.; Pez, M.; Quentel, F.

    2006-04-01

    Very short range (VSR) high bit rate optical fiber communications are an emerging market dedicated to local area networks, digital displays or board to board interconnects within real time calculators. In this technology, a very fast way to exchange data with high noise immunity and low-cost is needed. Optical multimode graded index fibers are used here because they have electrical noise immunity and are easier to handle than monomode fibers. 850 nm VCSEL are used in VSR communications because of their low cost, direct on-wafer tests, and the possibility of manufacturing VCSEL arrays very easily compared to classical optical transceivers using edge-emitting laser diodes. Although much research has been carried out in temperature modeling on VCSEL emitters, few studies have been devoted to characterizations over a very broad range of temperatures. Nowadays, VCSEL VSR communications tend to be used in severe environments such as space, avionics and military equipments. Therefore, a simple way to characterize VCSEL emitters over a broad range of temperature is required. In this paper, we propose a complete characterization of the emitter part of 2.5 Gb/s opto-electrical transceiver modules operating from -40°C to +120°C using 850 nm VCSELs. Our method uses simple and semi-automatic measurements of a given set of chosen device parameters in order to make fast and efficient simulations.

  10. Optical and structural characterization of the pure and doped BaY2F8 with rare earths for application in radiation detectors and scintillators

    International Nuclear Information System (INIS)

    Mello, Ana Carolina Santana de

    2008-01-01

    In this work Barium Yttrium Fluoride (BaY 2 F 8 -BaYF) doped with different concentrations of ions Tb 3+ , Er 3+ , Tm 3+ e Nd 3+ were characterized, aiming the application in radiation detection devices that use the scintillating properties. Two types of samples were produced in the CLA-IPEN-SP, polycrystalline samples, obtained via solid state reaction of BaF 2 and YF 3 under HF atmosphere, and single crystals, obtained via the zone melting method also in a HF atmosphere. The samples were characterized using the following experimental techniques: X-ray powder diffraction, Radioluminescence (RL), Optical Absorption and Dispersive X-ray Absorption Spectroscopy (DXAS). The X-ray diffraction pattern showed the presence of the phase BaY 2 F 8 and a small amount of the phase Ba 4 Y 3 F 17 in the polycrystalline pure and Tb 3+ doped samples. The other samples showed only the desired BaY 2 F 8 phase. The radioluminescence measurements of the doped BaYF, when irradiated with X-rays, showed emission peaks in energies that are characteristics of the 4f-4f transitions of rare earths. The RL of the samples with 2 mol por cent and 3 mold of Tb 3+ showed quite intense peaks with a maximum emission peak at 545 nm. The Tm 3+ doped BYF showed that the scintillation efficiency is not directly proportional to the doping level, and the highest RL emission were obtained for the polycrystalline samples doped with 1 mol por cent, showing a maximum peak intensity at 456 nm (the blue region of the visible spectrum). All samples showed a phosphorescent decay time of the order of seconds. Single crystals of BaYF doped with 2 mol por cent of Er 3+ , in addition to one of the highest phosphorescence time, presents a quite strong Rl in the green region of the spectra. The radiation damage was evaluated by the optical absorption techniques and the results showed that the formation of the absorption bands can be connected to colors centers generated by radiation in the matrix. Measurements of

  11. Characterization of the viscoelastic behavior of the pure bitumen grades 10/20 and 35/50 with macroindentation and finite element computation

    KAUST Repository

    Hamzaoui, Rabah; Guessasma, Sofiane; Bennabi, Abdelkrim

    2013-01-01

    In this article, we present an identification procedure that allows the determination of the viscoelasticity behavior of different grades of pure bitumen (bitumen 35/50 and bitumen 10/20). The procedure required in the first stage a mechanical

  12. Mechanical characterization of polymers and composites with a servohydraulic high-speed tensile tester

    Science.gov (United States)

    Béguelin, Ph.; Barbezat, M.; Kausch, H. H.

    1991-12-01

    This study is concerned with the measurement of the mechanical behaviour of polymers and composites at intermediate strain rates. It illustrates with two examples, the application of a high speed servohydraulic testing machine and a newly designed optical extensometer. In the first part of the study, the dynamic nature of high speed tensile testing with servohydraulic apparatus is discussed, and a damping technique is proposed. In the second part, this technique has been applied to the measurement of the tensile properties of annealed and unannealed neat PEEK at strain rates between 3 × 10^{-2} and 2,4 × 10^2 s^{-1}. Both materials show increased yield stress and drawing stress with increasing strain rate. However, annealed specimens have been shown to exhibit superior mechanical properties. In the third part, mode I delamination tests have been performed on unidirectional IM6/PEEK composites at nominal strain rates between 1 × 10^{-6} and 8 × 10^{-1} s^{-1}. At the higher velocities the analysis is performed by means of FFT filtering. A moderate reduction in interlaminar fracture toughness was found with increasing loading rate. Cette étude aborde la mesure des propriétés mécaniques des polymères et composites soumis à des vitesses de déformation moyennes. Elle illustre au travers de deux exemples l'utilisation d'une machine d'essais servo-hydraulique à grande vitesse. Elle présente également un capteur optique d'extensométrie de conception nouvelle. Dans la première partie de l'étude, la nature vibratoire des essais de traction à vitesse élevée réalisés sur une machine servo-hydraulique est discutée, et une technique d'amortissement est proposée. Dans une deuxième partie, cette technique est appliquée à l'étude des propriétés en traction du PEEK non recuit et recuit dans le domaine des vitesses de déformation de 3 × 10^{-2} à 2,4 × 10^2 s^{-1}. Les résultats montrent un accroissement systématique de la contrainte au seuil

  13. High-speed crystal detection and characterization using a fast-readout detector.

    Science.gov (United States)

    Aishima, Jun; Owen, Robin L; Axford, Danny; Shepherd, Emma; Winter, Graeme; Levik, Karl; Gibbons, Paul; Ashton, Alun; Evans, Gwyndaf

    2010-09-01

    A novel raster-scanning method combining continuous sample translation with the fast readout of a Pilatus P6M detector has been developed on microfocus beamline I24 at Diamond Light Source. This fast grid-scan tool allows the rapid evaluation of large sample volumes without the need to increase the beam size at the sample through changes in beamline hardware. A slow version is available for slow-readout detectors. Examples of grid-scan use in centring optically invisible samples and in detecting and characterizing numerous microcrystals on a mesh-like holder illustrate the most common applications of the grid scan now in routine use on I24.

  14. Shelter Index and a simple wind speed parameter to characterize vegetation control of sand transport threshold and Flu

    Science.gov (United States)

    Gillies, J. A.; Nield, J. M.; Nickling, W. G.; Furtak-Cole, E.

    2014-12-01

    Wind erosion and dust emissions occur in many dryland environments from a range of surfaces with different types and amounts of vegetation. Understanding how vegetation modulates these processes remains a research challenge. Here we present results from a study that examines the relationship between an index of shelter (SI=distance from a point to the nearest upwind vegetation/vegetation height) and particle threshold expressed as the ratio of wind speed measured at 0.45 times the mean plant height divided by the wind speed at 17 m when saltation commences, and saltation flux. The results are used to evaluate SI as a parameter to characterize the influence of vegetation on local winds and sediment transport conditions. Wind speed, wind direction, saltation activity and point saltation flux were measured at 35 locations in defined test areas (~13,000 m2) in two vegetation communities: mature streets of mesquite covered nebkhas and incipient nebkhas dominated by low mesquite plants. Measurement positions represent the most open areas, and hence those places most susceptible to wind erosion among the vegetation elements. Shelter index was calculated for each measurement position for each 10° wind direction bin using digital elevation models for each site acquired using terrestrial laser scanning. SI can show the susceptibility to wind erosion at different time scales, i.e., event, seasonal, or annual, but in a supply-limited system it can fail to define actual flux amounts due to a lack of knowledge of the distribution of sediment across the surface of interest with respect to the patterns of SI.

  15. Polarized ensembles of random pure states

    International Nuclear Information System (INIS)

    Cunden, Fabio Deelan; Facchi, Paolo; Florio, Giuseppe

    2013-01-01

    A new family of polarized ensembles of random pure states is presented. These ensembles are obtained by linear superposition of two random pure states with suitable distributions, and are quite manageable. We will use the obtained results for two purposes: on the one hand we will be able to derive an efficient strategy for sampling states from isopurity manifolds. On the other, we will characterize the deviation of a pure quantum state from separability under the influence of noise. (paper)

  16. Polarized ensembles of random pure states

    Science.gov (United States)

    Deelan Cunden, Fabio; Facchi, Paolo; Florio, Giuseppe

    2013-08-01

    A new family of polarized ensembles of random pure states is presented. These ensembles are obtained by linear superposition of two random pure states with suitable distributions, and are quite manageable. We will use the obtained results for two purposes: on the one hand we will be able to derive an efficient strategy for sampling states from isopurity manifolds. On the other, we will characterize the deviation of a pure quantum state from separability under the influence of noise.

  17. Evaluation of interface characterization and adhesion of glass ceramics to commercially pure titanium and gold alloy after thermal- and mechanical-loading

    NARCIS (Netherlands)

    Ccahuana Vasqueza, Vanessa Zulema; Ozcan, Mutlu; Kimpara, Estevao Tomomitsu

    Objectives. This study evaluated the effect of thermal- and mechanical-cycling on the shear bond strength of three low-fusing glassy matrix dental ceramics to commercial pure titanium (cpTi) when compared to conventional feldspathic ceramic fused to gold alloy. Methods. Metallic frameworks

  18. Calculus migration characterization during Ho:YAG laser lithotripsy by high-speed camera using suspended pendulum method.

    Science.gov (United States)

    Zhang, Jian James; Rajabhandharaks, Danop; Xuan, Jason Rongwei; Chia, Ray W J; Hasenberg, Thomas

    2017-07-01

    Calculus migration is a common problem during ureteroscopic laser lithotripsy procedure to treat urolithiasis. A conventional experimental method to characterize calculus migration utilized a hosting container (e.g., a "V" grove or a test tube). These methods, however, demonstrated large variation and poor detectability, possibly attributed to the friction between the calculus and the container on which the calculus was situated. In this study, calculus migration was investigated using a pendulum model suspended underwater to eliminate the aforementioned friction. A high-speed camera was used to study the movement of the calculus which covered zero order (displacement), first order (speed), and second order (acceleration). A commercialized, pulsed Ho:YAG laser at 2.1 μm, a 365-μm core diameter fiber, and a calculus phantom (Plaster of Paris, 10 × 10 × 10 mm 3 ) was utilized to mimic laser lithotripsy procedure. The phantom was hung on a stainless steel bar and irradiated by the laser at 0.5, 1.0, and 1.5 J energy per pulse at 10 Hz for 1 s (i.e., 5, 10, and 15 W). Movement of the phantom was recorded by a high-speed camera with a frame rate of 10,000 FPS. The video data files are analyzed by MATLAB program by processing each image frame and obtaining position data of the calculus. With a sample size of 10, the maximum displacement was 1.25 ± 0.10, 3.01 ± 0.52, and 4.37 ± 0.58 mm for 0.5, 1, and 1.5 J energy per pulse, respectively. Using the same laser power, the conventional method showed <0.5 mm total displacement. When reducing the phantom size to 5 × 5 × 5 mm 3 (one eighth in volume), the displacement was very inconsistent. The results suggested that using the pendulum model to eliminate the friction improved sensitivity and repeatability of the experiment. A detailed investigation on calculus movement and other causes of experimental variation will be conducted as a future study.

  19. Sixth form pure mathematics

    CERN Document Server

    Plumpton, C

    1968-01-01

    Sixth Form Pure Mathematics, Volume 1, Second Edition, is the first of a series of volumes on Pure Mathematics and Theoretical Mechanics for Sixth Form students whose aim is entrance into British and Commonwealth Universities or Technical Colleges. A knowledge of Pure Mathematics up to G.C.E. O-level is assumed and the subject is developed by a concentric treatment in which each new topic is used to illustrate ideas already treated. The major topics of Algebra, Calculus, Coordinate Geometry, and Trigonometry are developed together. This volume covers most of the Pure Mathematics required for t

  20. Spray Droplet Characterization from a Single Nozzle by High Speed Image Analysis Using an In-Focus Droplet Criterion.

    Science.gov (United States)

    Minov, Sofija Vulgarakis; Cointault, Frédéric; Vangeyte, Jürgen; Pieters, Jan G; Nuyttens, David

    2016-02-06

    Accurate spray characterization helps to better understand the pesticide spray application process. The goal of this research was to present the proof of principle of a droplet size and velocity measuring technique for different types of hydraulic spray nozzles using a high speed backlight image acquisition and analysis system. As only part of the drops of an agricultural spray can be in focus at any given moment, an in-focus criterion based on the gray level gradient was proposed to decide whether a given droplet is in focus or not. In a first experiment, differently sized droplets were generated with a piezoelectric generator and studied to establish the relationship between size and in-focus characteristics. In a second experiment, it was demonstrated that droplet sizes and velocities from a real sprayer could be measured reliably in a non-intrusive way using the newly developed image acquisition set-up and image processing. Measured droplet sizes ranged from 24 μm to 543 μm, depending on the nozzle type and size. Droplet velocities ranged from around 0.5 m/s to 12 m/s. The droplet size and velocity results were compared and related well with the results obtained with a Phase Doppler Particle Analyzer (PDPA).

  1. Generalized pure Lovelock gravity

    Science.gov (United States)

    Concha, Patrick; Rodríguez, Evelyn

    2017-11-01

    We present a generalization of the n-dimensional (pure) Lovelock Gravity theory based on an enlarged Lorentz symmetry. In particular, we propose an alternative way to introduce a cosmological term. Interestingly, we show that the usual pure Lovelock gravity is recovered in a matter-free configuration. The five and six-dimensional cases are explicitly studied.

  2. Generalized pure Lovelock gravity

    Directory of Open Access Journals (Sweden)

    Patrick Concha

    2017-11-01

    Full Text Available We present a generalization of the n-dimensional (pure Lovelock Gravity theory based on an enlarged Lorentz symmetry. In particular, we propose an alternative way to introduce a cosmological term. Interestingly, we show that the usual pure Lovelock gravity is recovered in a matter-free configuration. The five and six-dimensional cases are explicitly studied.

  3. Characterization for solidification and phase transformations of pure-titanium steel weld metal with time-resolved X-ray diffraction system

    International Nuclear Information System (INIS)

    Terasaki, Hidenori; Komizo, Yu-ichi; Nishino, Fumihiro; Ikeda, Masahiko

    2007-01-01

    Understanding and controlling solidification and phase transformation process of weld metal is essential for forming the microstructure with superior mechanical property. Recent evolution of analysis technique makes for solidification and phase transformation process to be in-situ analyzed, in direct and reciprocal lattice space. In the present work, unidirectional-solidification and phase transformation in the weld metal of commercial pure-titanium in Gas Tungsten Arc welding was in-situ observed by using Time-Resolved X-Ray Diffraction system with two-dimensional pixel detector. An undulator beam was used as a probe. Larger diffraction area could be detected in the time-resolution of 0.05 seconds, in unidirectional solidification and subsequent phase transformation process of pure-titanium weld metal. Furthermore, the microstructure formation during β-α phase transformation was in situ observed with High temperature Laser Scanning Confocal Microscopy. The crystal configurations in unidirectional solidification of weld metal and rapid change of phase ratio in reconstructive phase transformation were clearly analyzed. (author)

  4. Structural and Electrochemical Characterization of Pure LiFePO4 and Nanocomposite C-LiFePO4 Cathodes for Lithium Ion Rechargeable Batteries

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2009-01-01

    Full Text Available Pure lithium iron phosphate (LiFePO4 and carbon-coated LiFePO4 (C-LiFePO4 cathode materials were synthesized for Li-ion batteries. Structural and electrochemical properties of these materials were compared. X-ray diffraction revealed orthorhombic olivine structure. Micro-Raman scattering analysis indicates amorphous carbon, and TEM micrographs show carbon coating on LiFePO4 particles. Ex situ Raman spectrum of C-LiFePO4 at various stages of charging and discharging showed reversibility upon electrochemical cycling. The cyclic voltammograms of LiFePO4 and C-LiFePO4 showed only a pair of peaks corresponding to the anodic and cathodic reactions. The first discharge capacities were 63, 43, and 13 mAh/g for C/5, C/3, and C/2, respectively for LiFePO4 where as in case of C-LiFePO4 that were 163, 144, 118, and 70 mAh/g for C/5, C/3, C/2, and 1C, respectively. The capacity retention of pure LiFePO4 was 69% after 25 cycles where as that of C-LiFePO4 was around 97% after 50 cycles. These results indicate that the capacity and the rate capability improved significantly upon carbon coating.

  5. Prediction of mechanical properties in friction stir welds of pure copper

    International Nuclear Information System (INIS)

    Heidarzadeh, A.; Saeid, T.

    2013-01-01

    Highlights: • Range of parameters for defect-free friction stir welded pure copper was reached. • Models were developed for predicting UTS, TE and hardness of pure copper joints. • Analysis of variance was used to validate the developed models. • Effect of welding parameters on mechanical behavior of welded joints was explored. • The microstructure and fracture surface of welded joints were investigated. - Abstract: This research was carried out to predict the mechanical properties of friction stir welded pure copper joints. Response surface methodology based on a central composite rotatable design with three parameters, five levels, and 20 runs, was used to conduct the experiments and to develop the mathematical regression model by using of Design-Expert software. The three welding parameters considered were rotational speed, welding speed, and axial force. Analysis of variance was applied to validate the predicted models. Microstructural characterization and fractography of joints were examined using optical and scanning electron microscopes. Also, the effects of the welding parameters on mechanical properties of friction stir welded joints were analyzed in detail. The results showed that the developed models were reasonably accurate. The increase in welding parameters resulted in increasing of tensile strength of the joints up to a maximum value. Elongation percent of the joints increased with increase of rotational speed and axial force, but decreased by increasing of welding speed, continuously. In addition, hardness of the joints decreased with increase of rotational speed and axial force, but increased by increasing of welding speed. The joints welded at higher heat input conditions revealed more ductility fracture mode

  6. Measuring the speed of dark: Detecting dark energy perturbations

    International Nuclear Information System (INIS)

    Putter, Roland de; Huterer, Dragan; Linder, Eric V.

    2010-01-01

    The nature of dark energy can be probed not only through its equation of state but also through its microphysics, characterized by the sound speed of perturbations to the dark energy density and pressure. As the sound speed drops below the speed of light, dark energy inhomogeneities increase, affecting both cosmic microwave background and matter power spectra. We show that current data can put no significant constraints on the value of the sound speed when dark energy is purely a recent phenomenon, but can begin to show more interesting results for early dark energy models. For example, the best fit model for current data has a slight preference for dynamics [w(a)≠-1], degrees of freedom distinct from quintessence (c s ≠1), and early presence of dark energy [Ω de (a<<1)≠0]. Future data may open a new window on dark energy by measuring its spatial as well as time variation.

  7. Pure partial monosomy 3p (3p25.3 → pter: Prenatal diagnosis and array comparative genomic hybridization characterization

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2012-09-01

    Conclusion: In this case, aCGH has characterized a 3p deleted region with haploinsufficiency of the neurodevelopmental genes associated with cognitive deficit and mental retardation but without involvement of the congenital heart disease susceptibility locus, and QF-PCR has determined a paternal origin of the deletion. aCGH and QF-PCR help to delineate the genomic imbalance in prenatally detected de novo chromosome aberration, and the information acquired is useful for genetic counseling.

  8. Pure natural inflation

    Directory of Open Access Journals (Sweden)

    Yasunori Nomura

    2018-01-01

    Full Text Available We point out that a simple inflationary model in which the axionic inflaton couples to a pure Yang–Mills theory may give the scalar spectral index (ns and tensor-to-scalar ratio (r in complete agreement with the current observational data.

  9. Language as Pure Potential

    Science.gov (United States)

    Park, Joseph Sung-Yul

    2016-01-01

    Language occupies a crucial position in neoliberalism, due to the reimagination of language as commodified skill. This paper studies the role of language ideology in this transformation by identifying a particular ideology that facilitates this process, namely the ideology which views language as pure potential. Neoliberalism treats language as a…

  10. Production of pure metals

    Science.gov (United States)

    Philipp, W. H.; Marsik, S. J.; May, C. E. (Inventor)

    1974-01-01

    A process for depositing elements by irradiating liquids is reported. Ultra pure elements are precipitated from aqueous solutions or suspensions of compounds. A solution of a salt of a metal to be prepared is irradiated, and the insoluble reaction product settles out. Some chemical compounds may also be prepared in this manner.

  11. Pure γ-families

    International Nuclear Information System (INIS)

    Dunaevskii, A.M.

    1977-01-01

    The subject of this work are pure gamma families consisting of the gamma quanta produced in the early stages of cosmic cascades. The criteria of selecting these families from the all measured families are presented. The characteristics of these families are given and some conclusions about the mechanism of the nuclear-electromagnetic cascades are extracted. (S.B.)

  12. Dahlbeck and Pure Ontology

    Science.gov (United States)

    Mackenzie, Jim

    2016-01-01

    This article responds to Johan Dahlbeck's "Towards a pure ontology: Children's bodies and morality" ["Educational Philosophy and Theory," vol. 46 (1), 2014, pp. 8-23 (EJ1026561)]. His arguments from Nietzsche and Spinoza do not carry the weight he supposes, and the conclusions he draws from them about pedagogy would be…

  13. Pure natural inflation

    Science.gov (United States)

    Nomura, Yasunori; Watari, Taizan; Yamazaki, Masahito

    2018-01-01

    We point out that a simple inflationary model in which the axionic inflaton couples to a pure Yang-Mills theory may give the scalar spectral index (ns) and tensor-to-scalar ratio (r) in complete agreement with the current observational data.

  14. Prediction of grain size and mechanical properties in friction stir welded pure copper joints using a thermal model

    DEFF Research Database (Denmark)

    Heidarzadeh, A.; Jabbaribehnam, Mirmasoud; Esmaily, M.

    2015-01-01

    In this study, a thermal model was developed and applied to simulate the friction stir welding of pure copper plates with the thickness of 2 mm. The different traverse speeds of 100, 200, 300, and 400 mm min−1 and rotational speeds of 400, 700, 900 rev min−1 were considered as welding parameters....... Microstructural characterization, hardness measurement, tensile test, and fractography were conducted experimentally. The comparison between the numerical and experimental results showed that the developed model was practically accurate. In addition, the results confirmed that the peak temperature...

  15. Pure chiral optical fibres.

    Science.gov (United States)

    Poladian, L; Straton, M; Docherty, A; Argyros, A

    2011-01-17

    We investigate the properties of optical fibres made from chiral materials, in which a contrast in optical activity forms the waveguide, rather than a contrast in the refractive index; we refer to such structures as pure chiral fibres. We present a mathematical formulation for solving the modes of circularly symmetric examples of such fibres and examine the guidance and polarisation properties of pure chiral step-index, Bragg and photonic crystal fibre designs. Their behaviour is shown to differ for left- and right-hand circular polarisation, allowing circular polarisations to be isolated and/or guided by different mechanisms, as well as differing from equivalent non-chiral fibres. The strength of optical activity required in each case is quantified.

  16. Purely leptonic currents

    International Nuclear Information System (INIS)

    Gourdin, M.

    1976-01-01

    In most gauge theories weak neutral currents appear as a natural consequence of the models, but the specific properties are not predicted in a general way. In purely leptonic interactions the structure of these currents can be tested without making assumptions about the weak couplings of the hadrons. The influence of neutral currents appearing in the process e + e - → μ + μ - can be measured using the polarization of the outgoing myons. (BJ) [de

  17. Purely Functional Structured Programming

    OpenAIRE

    Obua, Steven

    2010-01-01

    The idea of functional programming has played a big role in shaping today's landscape of mainstream programming languages. Another concept that dominates the current programming style is Dijkstra's structured programming. Both concepts have been successfully married, for example in the programming language Scala. This paper proposes how the same can be achieved for structured programming and PURELY functional programming via the notion of LINEAR SCOPE. One advantage of this proposal is that m...

  18. Characterization of in vivo Achilles tendon forces in rabbits during treadmill locomotion at varying speeds and inclinations.

    Science.gov (United States)

    West, John R; Juncosa, Natalia; Galloway, Marc T; Boivin, Gregory P; Butler, David L

    2004-11-01

    The objective of this study was to test the hypothesis that increasing the speed and inclination of the treadmill increases the peak Achilles tendon forces and their rates of rise and fall in force. Implantable force transducers (IFT) were inserted in the confluence of the medial and lateral heads of the left gastrocnemius tendon in 11 rabbits. IFT voltages were successfully recorded in 8 animals as the animals hopped on a treadmill at each of two speeds (0.1 and 0.3 mph) and inclinations (0 degrees and 12 degrees). Instrumented tendons were isolated shortly after sacrifice and calibrated. Contralateral unoperated tendons were failed in uniaxial tension to determine maximum or failure force, from which safety factor (ratio of maximum force to peak in vivo force) was calculated for each activity. Peak force and the rates of rise and fall in force significantly increased with increasing treadmill inclination (prabbit Achilles tendon and other tendon repairs. Force patterns can also serve as input data for mechanical stimulation of tissue-engineered constructs in culture. Such approaches are expected to help accelerate tendon repair after injury.

  19. Is the propagation speed of ultrasound in human organs a diagnostic parameter for tissue characterization? Evaluation using the liver parenchyma in children and adolescents as an example

    International Nuclear Information System (INIS)

    Born, M.; Franke, I.

    2011-01-01

    New sonographic machines permit the measurement of the propagation speed of ultrasound (PSU) in humans. The liver seems to be an appropriate organ for examining whether the PSU may be used as a diagnostic parameter for tissue characterization since the liver is easily accessible to sonography and its variable content of fat impacts the PSU. Purpose: To determine whether there is a measurable correlation between obesity and PSU in the liver. Methods: In 69 children and adolescents, the PSU in the liver was measured sonographically and correlated to BMI, age, size and weight of the children. Results: A strong correlation was found between the PSU in the liver and the BMI. The PSU was significantly lower in obese children (1507 m/s) than in children with normal body weight (1564 m/s). Conclusion: PSU seems to be promising as an additional diagnostic parameter for characterizing liver tissue. Further evaluation is necessary. (orig.)

  20. Preparation of pure phenols from tars

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J

    1929-06-18

    A process is disclosed for preparing pure phenols from brown coal and shale tar, characterized in that the alkaline extract obtained from the tar is oxidized and concurrently the alkaline solution is separated from the existing impurities by heating with steam at high temperature, which finally reaches at least 150/sup 0/C.

  1. Pure homology of algebraic varieties

    OpenAIRE

    Weber, Andrzej

    2003-01-01

    We show that for a complete complex algebraic variety the pure component of homology coincides with the image of intersection homology. Therefore pure homology is topologically invariant. To obtain slightly more general results we introduce "image homology" for noncomplete varieties.

  2. Characterization of a 512x512-pixel 8-output full-frame CCD for high-speed imaging

    Science.gov (United States)

    Graeve, Thorsten; Dereniak, Eustace L.

    1993-01-01

    The characterization of a 512 by 512 pixel, eight-output full frame CCD manufactured by English Electric Valve under part number CCD13 is discussed. This device is a high- resolution Silicon-based array designed for visible imaging applications at readout periods as low as two milliseconds. The characterization of the device includes mean-variance analysis to determine read noise and dynamic range, as well as charge transfer efficiency, MTF, and quantum efficiency measurements. Dark current and non-uniformity issues on a pixel-to-pixel basis and between individual outputs are also examined. The characterization of the device is restricted by hardware limitations to a one MHz pixel rate, corresponding to a 40 ms readout time. However, subsections of the device have been operated at up to an equivalent 100 frames per second. To maximize the frame rate, the CCD is illuminated by a synchronized strobe flash in between frame readouts. The effects of the strobe illumination on the imagery obtained from the device is discussed.

  3. Sonochemical and high-speed optical characterization of cavitation generated by an ultrasonically oscillating dental file in root canal models.

    Science.gov (United States)

    Macedo, R G; Verhaagen, B; Fernandez Rivas, D; Gardeniers, J G E; van der Sluis, L W M; Wesselink, P R; Versluis, M

    2014-01-01

    Ultrasonically Activated Irrigation makes use of an ultrasonically oscillating file in order to improve the cleaning of the root canal during a root canal treatment. Cavitation has been associated with these oscillating files, but the nature and characteristics of the cavitating bubbles were not yet fully elucidated. Using sensitive equipment, the sonoluminescence (SL) and sonochemiluminescence (SCL) around these files have been measured in this study, showing that cavitation occurs even at very low power settings. Luminol photography and high-speed visualizations provided information on the spatial and temporal distribution of the cavitation bubbles. A large bubble cloud was observed at the tip of the files, but this was found not to contribute to SCL. Rather, smaller, individual bubbles observed at antinodes of the oscillating file with a smaller amplitude were leading to SCL. Confinements of the size of bovine and human root canals increased the amount of SL and SCL. The root canal models also showed the occurrence of air entrainment, resulting in the generation of stable bubbles, and of droplets, near the air-liquid interface and leading eventually to a loss of the liquid. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Synthesis and characterization of NaCo(1-x)MnxO2 solid electrolyte using sol-gel method: the effect of milling speed variations

    Science.gov (United States)

    Suyati, L.; Widyayanti, O. A.; Qushoyyi, M.; Darmawan, A.; Nuryanto, R.

    2018-04-01

    Battery is a device that converts chemical energy into electrical energy through electrochemical process. Further research on the synthesis of cathode of Na-ion battery that has good conductivity to maximize the battery performance needs to be conducted. One of the production steps of the NaCo(1-x)NaCo cathode synthesis in the Na-Ion battery was a ball-milling process, in which by the ball-milling process, the crystal size of NaCo(1-x)MnxO2 cathode can be minimized. The purpose of this study was to determine the effect of variation of ball-milling speed to the characteristics of resulting product including the oxide types composing NaCo(1-x)MnxO2 cathode, surface morphology, and conductivity. The main ingredients used were sodium acetate, manganese acetate, cobalt acetate with molar ratio of 0.7: 0.66: 0.22, respectively and citric acid as chelating agent with the M/CA ratio of 1: 1. The variations of milling speed were 0, 300, 400, 500, 600 and 700 rpm. Characterization of the product was conducted using XRD, SEM-EDS, and conductivity meter (LCR-meter). The result showed that a solid electrolyte of NaCo(1-x)MnxO2 consisting of NaMnO2, NaO2, CoO, Co2O3, MnO2 components was successfully synthesized. The observation on the milling speed at 400 rpm showed that the solid electrolyte produced had the highest conductivity i.e. 4.08 x 10-6 Scm-1 with a homogeneous surface morphology and had a spinel formula NaCo0,65Mn0,35O2.

  5. New Technologies Provide Quantum Changes in the Scale, Speed, and Success of SELEX Methods and Aptamer Characterization

    Directory of Open Access Journals (Sweden)

    Abdullah Ozer

    2014-01-01

    Full Text Available Single-stranded oligonucleotide aptamers have attracted great attention in the past decade because of their diagnostic and therapeutic potential. These versatile, high affinity and specificity reagents are selected by an iterative in vitro process called SELEX, Systematic Evolution of Ligands by Exponential Enrichment. Numerous SELEX methods have been developed for aptamer selections; some that are simple and straightforward, and some that are specialized and complicated. The method of SELEX is crucial for selection of an aptamer with desired properties; however, success also depends on the starting aptamer library, the target molecule, aptamer enrichment monitoring assays, and finally, the analysis and characterization of selected aptamers. Here, we summarize key recent developments in aptamer selection methods, as well as other aspects of aptamer selection that have significant impact on the outcome. We discuss potential pitfalls and limitations in the selection process with an eye to aid researchers in the choice of a proper SELEX strategy, and we highlight areas where further developments and improvements are desired. We believe carefully designed multiplexed selection methods, when complemented with high-throughput downstream analysis and characterization assays, will yield numerous high-affinity aptamers to protein and small molecule targets, and thereby generate a vast array of reagents for probing basic biological mechanisms and implementing new diagnostic and therapeutic applications in the near future.

  6. Characterization of hard nitride and carbide titanium and zirconium coatings on high-speed steel cutting tool inserts

    International Nuclear Information System (INIS)

    Fenske, G.; Kaufherr, N.; Albertson, C.; Mapalo, G.; Nielsen, R.; Kaminsky, M.

    1986-01-01

    Hard nitride and carbide coatings of titanium and zirconium deposited by reactive evaporation and reactive sputtering techniques were characterized by electron microscopy and Auger spectroscopy to determine the effect of coating process on coating composition and microstructure. Analysis of the chemical composition by Auger spectroscopy revealed the coatings were of high purity with slight differences in stoichiometry depending on the coating technique. Both techniques produced coatings with a columnar microstructure. However, the reactive sputtering technique produced coarser (shorter and wider) columnar grains than the reactive evaporation technique. Furthermore, selected area diffraction analysis of reactively sputtered ZrN coatings showed a two-phased zone (hcp Zr and fcc ZrN) near the substrate/coating interface, while TiC coatings deposited by reactive sputtering and evaporation only showed a single-phase region of fcc TiC

  7. Scaling model for a speed-dependent vehicle noise spectrum

    Directory of Open Access Journals (Sweden)

    Giovanni Zambon

    2017-06-01

    Full Text Available Considering the well-known features of the noise emitted by moving sources, a number of vehicle characteristics such as speed, unladen mass, engine size, year of registration, power and fuel were recorded in a dedicated monitoring campaign performed in three different places, each characterized by different number of lanes and the presence of nearby reflective surfaces. A full database of 144 vehicles (cars was used to identify statistically relevant features. In order to compare the vehicle transit noise in different environmental condition, all 1/3-octave band spectra were normalized and analysed. Unsupervised clustering algorithms were employed to group together spectrum levels with similar profiles. Our results corroborate the well-known fact that speed is the most relevant characteristic to discriminate between different vehicle noise spectrum. In keeping with this fact, we present a new approach to predict analytically noise spectra for a given vehicle speed. A set of speed-dependent analytical functions are suggested in order to fit the normalized average spectrum profile at different speeds. This approach can be useful for predicting vehicle speed based purely on its noise spectrum pattern. The present work is complementary to the accurate analysis of noise sources based on the beamforming technique.

  8. Bringing Planctomycetes into pure culture

    Directory of Open Access Journals (Sweden)

    Olga Maria Lage

    2012-12-01

    Full Text Available Planctomycetes have been known since the description of Planctomyces bekefii by Gimesi at the beginning of the twentieth century (1924, although the first axenic cultures were only obtained in the 1970s. Since then, eleven genera with fourteen species have been validly named and five candidatus genera belonging to the anaerobic ammonium oxidation, anammox bacteria have also been discovered. However, Planctomycetes diversity is much broader than these numbers indicate, as shown by environmental molecular studies. In recent years the authors have attempted to isolate and cultivate additional strains of Planctomycetes. This paper provides a summary of the isolation work that was carried out to obtain in pure culture Planctomycetes from several environmental sources. The following strains and planctomycetes have been successfully isolated: two freshwater strains from the sediments of an aquarium, which were described as a new genus and species, Aquisphaera giovannonii; several Rhodopirellula strains from the sediments of a water treatment recycling tank of a marine fish farm; and more than 140 planctomycetes from the biofilm community of macroalgae. This collection comprises several novel taxa that are being characterized and described. Improvements in the isolation methodology were made in order to optimize and enlarge the number of Planctomycetes isolated from the macroalgae. The existence of an intimate and an important relationship between planctomycetes and macroalgae reported before by molecular studies is therefore supported by culture dependent methods.

  9. Preparation of pure phenols from tars

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J

    1933-02-07

    A process is disclosed for the preparation of pure phenols from brown coal tar, shale tar, or primary tar, characterized in that the raw oil obtained from the tar is carefully fractionated, in a suitable way without or with a slight pressure decrease, or before the fractionation the raw oil is heated to free the prepared phenolate solution from impurities after successful oxidation by passing in steam at a temperature between 100 and 120/sup 0/C.

  10. Method of producing vegetable puree

    DEFF Research Database (Denmark)

    2004-01-01

    A process for producing a vegetable puree, comprising the sequential steps of: a)crushing, chopping or slicing the vegetable into pieces of 1 to 30 mm; b) blanching the vegetable pieces at a temperature of 60 to 90°C; c) contacted the blanched vegetable pieces with a macerating enzyme activity; d......) blending the macerated vegetable pieces and obtaining a puree....

  11. Magnetic characterization of the stator core of a high-speed motor made of an ultrathin electrical steel sheet using the magnetic property evaluation system

    Directory of Open Access Journals (Sweden)

    Mohachiro Oka

    2018-04-01

    Full Text Available Recently, the application areas for electric motors have been expanding. For instance, electric motors are used in new technologies such as rovers, drones, cars, and robots. The motor used in such machinery should be small, high-powered, highly-efficient, and high-speed. In such motors, loss at high-speed rotation must be especially minimal. Eddy-current loss in the stator core is known to increase greatly during loss at high-speed rotation of the motor. To produce an efficient high-speed motor, we are developing a stator core for a motor using an ultrathin electrical steel sheet with only a small amount of eddy-current loss. Furthermore, the magnetic property evaluation for efficient, high-speed motor stator cores that use conventional commercial frequency is insufficient. Thus, we made a new high-speed magnetic property evaluation system to evaluate the magnetic properties of the efficient high-speed motor stator core. This system was composed of high-speed A/D converters, D/A converters, and a high-speed power amplifier. In experiments, the ultrathin electrical steel sheet dramatically suppressed iron loss and, in particular, eddy-current loss. In addition, a new high-speed magnetic property evaluation system accurately evaluated the magnetic properties of the efficient high-speed motor stator core.

  12. Magnetic characterization of the stator core of a high-speed motor made of an ultrathin electrical steel sheet using the magnetic property evaluation system

    Science.gov (United States)

    Oka, Mohachiro; Enokizono, Masato; Mori, Yuji; Yamazaki, Kazumasa

    2018-04-01

    Recently, the application areas for electric motors have been expanding. For instance, electric motors are used in new technologies such as rovers, drones, cars, and robots. The motor used in such machinery should be small, high-powered, highly-efficient, and high-speed. In such motors, loss at high-speed rotation must be especially minimal. Eddy-current loss in the stator core is known to increase greatly during loss at high-speed rotation of the motor. To produce an efficient high-speed motor, we are developing a stator core for a motor using an ultrathin electrical steel sheet with only a small amount of eddy-current loss. Furthermore, the magnetic property evaluation for efficient, high-speed motor stator cores that use conventional commercial frequency is insufficient. Thus, we made a new high-speed magnetic property evaluation system to evaluate the magnetic properties of the efficient high-speed motor stator core. This system was composed of high-speed A/D converters, D/A converters, and a high-speed power amplifier. In experiments, the ultrathin electrical steel sheet dramatically suppressed iron loss and, in particular, eddy-current loss. In addition, a new high-speed magnetic property evaluation system accurately evaluated the magnetic properties of the efficient high-speed motor stator core.

  13. Speed mathematics

    CERN Document Server

    Handley, Bill

    2012-01-01

    This new, revised edition of the bestselling Speed Mathematics features new chapters on memorising numbers and general information, calculating statistics and compound interest, square roots, logarithms and easy trig calculations. Written so anyone can understand, this book teaches simple strategies that will enable readers to make lightning-quick calculations. People who excel at mathematics use better strategies than the rest of us; they are not necessarily more intelligent. With Speed Mathematics you'll discover methods to make maths easy and fun. This book is perfect for stud

  14. Exploring the potential of open big data from ticketing websites to characterize travel patterns within the Chinese high-speed rail system.

    Directory of Open Access Journals (Sweden)

    Sheng Wei

    Full Text Available Big data have contributed to deepen our understanding in regards to many human systems, particularly human mobility patterns and the structure and functioning of transportation systems. Resonating the recent call for 'open big data,' big data from various sources on a range of scales have become increasingly accessible to the public. However, open big data relevant to travelers within public transit tools remain scarce, hindering any further in-depth study on human mobility patterns. Here, we explore ticketing-website derived data that are publically available but have been largely neglected. We demonstrate the power, potential and limitations of this open big data, using the Chinese high-speed rail (HSR system as an example. Using an application programming interface, we automatically collected the data on the remaining tickets (RTD for scheduled trains at the last second before departure in order to retrieve information on unused transit capacity, occupancy rate of trains, and passenger flux at stations. We show that this information is highly useful in characterizing the spatiotemporal patterns of traveling behaviors on the Chinese HSR, such as weekend traveling behavior, imbalanced commuting behavior, and station functionality. Our work facilitates the understanding of human traveling patterns along the Chinese HSR, and the functionality of the largest HSR system in the world. We expect our work to attract attention regarding this unique open big data source for the study of analogous transportation systems.

  15. Vacuum evaporation of pure metals

    OpenAIRE

    Safarian, Jafar; Engh, Thorvald Abel

    2013-01-01

    Theories on the evaporation of pure substances are reviewed and applied to study vacuum evaporation of pure metals. It is shown that there is good agreement between different theories for weak evaporation, whereas there are differences under intensive evaporation conditions. For weak evaporation, the evaporation coefficient in Hertz-Knudsen equation is 1.66. Vapor velocity as a function of the pressure is calculated applying several theories. If a condensing surface is less than one collision...

  16. Interfacial Microstructure and Mechanical Properties of Friction Stir Welded Joints of Commercially Pure Aluminum and 304 Stainless Steel

    Science.gov (United States)

    Murugan, Balamagendiravarman; Thirunavukarasu, Gopinath; Kundu, Sukumar; Kailas, Satish V.; Chatterjee, Subrata

    2018-05-01

    In the present investigation, friction stir welding of commercially pure aluminum and 304 stainless steel was carried out at varying tool rotational speeds from 200 to 1000 rpm in steps of 200 rpm using 60 mm/min traverse speed at 2 (degree) tool tilt angle. Microstructural characterization of the interfacial zone was carried out using optical microscope and scanning electron microscope. Energy-dispersive spectroscopy indicated the presence of FeAl3 intermetallic phase. Thickness of the intermetallic layer increased with the increase in tool rotational speed. X-ray diffraction studies indicated the formation of intermetallic phases like FeAl2, Fe4Al13, Fe2Al5, and FeAl3. A maximum tensile strength of 90% that of aluminum along with 4.5% elongation was achieved with the welded sample at tool rotational speed of 400 rpm. The stir zone showed higher hardness as compared to base metals, heat affected zone, and thermo-mechanically affected zone due to the presence of intermetallics. The maximum hardness value at the stir zone was achieved at 1000 rpm tool rotational speed.

  17. Pure type systems with subtyping

    NARCIS (Netherlands)

    Zwanenburg, J.; Girard, J.-Y.

    1999-01-01

    We extend the framework of Pure Type Systems with subtyping, as found in F = ¿ . This leads to a concise description of many existing systems with subtyping, and also to some new interesting systems. We develop the meta-theory for this framework, including Subject Reduction and Minimal Typing. The

  18. Visual processing in pure alexia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Habekost, Thomas; Gerlach, Christian

    2010-01-01

    affected. His visual apprehension span was markedly reduced for letters and digits. His reduced visual processing capacity was also evident when reporting letters from words. In an object decision task with fragmented pictures, NN's performance was abnormal. Thus, even in a pure alexic patient with intact...

  19. Pure robotic retrocaval ureter repair

    Directory of Open Access Journals (Sweden)

    Ashok k. Hemal

    2008-12-01

    Full Text Available PURPOSE: To demonstrate the feasibility of pure robotic retrocaval ureter repair. MATERIALS AND METHODS: A 33 year old female presented with right loin pain and obstruction on intravenous urography with the classical "fish-hook" appearance. She was counseled on the various methods of repair and elected to have a robot assisted repair. The following steps are performed during a pure robotic retrocaval ureter repair. The patient is placed in a modified flank position, pneumoperitoneum created and ports inserted. The colon is mobilized to expose the retroperitoneal structures: inferior vena cava, right gonadal vein, right ureter, and duodenum. The renal pelvis and ureter are mobilized and the renal pelvis transected. The ureter is transposed anterior to the inferior vena cava and a pyelopyelostomy is performed over a JJ stent. RESULTS: This patient was discharged on postoperative day 3. The catheter and drain tube were removed on day 1. Her JJ stent was removed at 6 weeks postoperatively. The postoperative intravenous urography at 3 months confirmed normal drainage of contrast medium. CONCLUSION: Pure robotic retrocaval ureter is a feasible procedure; however, there does not appear to be any great advantage over pure laparoscopy, apart from the ergonomic ease for the surgeon as well the simpler intracorporeal suturing.

  20. Neutron Transport in Finite Random Media with Pure-Triplet Scattering

    International Nuclear Information System (INIS)

    Sallaha, M.; Hendi, A.A.

    2008-01-01

    The solution of the one-speed neutron transport equation in a finite slab random medium with pure-triplet anisotropic scattering is studied. The stochastic medium is assumed to consist of two randomly mixed immiscible fluids. The cross section and the scattering kernel are treated as discrete random variables, which obey the same statistics as Markovian processes and exponential chord length statistics. The medium boundaries are considered to have specular reflectivities with angular-dependent externally incident flux. The deterministic solution is obtained by using Pomraning-Eddington approximation. Numerical results are calculated for the average reflectivity and average transmissivity for different values of the single scattering albedo and varying the parameters which characterize the random medium. Compared to the results obtained by Adams et al. in case of isotropic scattering that based on the Monte Carlo technique, it can be seen that we have good comparable data

  1. A sustainable solid state recycling of pure aluminum by means of friction stir extrusion process (FSE)

    Science.gov (United States)

    Mehtedi, Mohamad El; Forcellese, Archimede; Simoncini, Michela; Spigarelli, Stefano

    2018-05-01

    In this research, the feasibility of solid-state recycling of pure aluminum AA1099 machining chips using FSE process is investigated. In the early stage, a FE simulation was conducted in order to optimize the die design and the process parameters in terms of plunge rotational speed and extrusion rate. The AA1099 aluminum chips were produced by turning of an as-received bar without lubrication. The chips were compacted on a MTS machine up to 150KN of load. The extruded samples were analyzed by optical and electron microscope in order to see the material flow and to characterize the microstructure. Finally, micro-hardness Vickers profiles were carried out, in both longitudinal and transversal direction of the obtained profiles, in order to investigate the homogeneity of the mechanical properties of the extrudate.

  2. Multimedia programming with pure data

    CERN Document Server

    Chung, Bryan

    2013-01-01

    A quick and comprehensive tutorial book for media designers to jump-start interactive multimedia production with computer graphics, digital audio, digital video, and interactivity, using the Pure Data graphical programming environment.An introductory book on multimedia programming for media artists/designers who like to work on interactivity in their projects, digital art/design students who like to learn the first multimedia programming technique, and audio-visual performers who like to customize their performance sets

  3. Pure Science and Applied Science

    Directory of Open Access Journals (Sweden)

    Robert J. Aumann

    2011-01-01

    Full Text Available (Excerpt The name of my talk is Pure Science and Applied Science, and the idea I would like to sell to you today is that there is no such thing as “pure” or “applied” science. In other words, there is such a thing as science, but there is no difference between pure and applied science. Science is one entity and cannot be separated into different categories. In order to back that up, I would like to tell you a little story. As an undergraduate, I studied mathematics at City College in New York. At that time, what was called Pure Mathematics was in vogue, and the more prominent mathematicians were a little contemptuous of any kind of application. A very famous, prominent mathematician in the first half of the previous century by the name of G. H. Hardy, who was in a branch of mathematics called number theory, said that the only thing he regretted was that he unwittingly did some important work in mathematical genetics that eventually turned out to have some application. … Such was the atmosphere in the late ’40s of the previous century and, being a young man and impressionable, I was swept up in this atmosphere.

  4. PSYCHE Pure Shift NMR Spectroscopy.

    Science.gov (United States)

    Foroozandeh, Mohammadali; Morris, Gareth; Nilsson, Mathias

    2018-03-13

    Broadband homodecoupling techniques in NMR, also known as "pure shift" methods, aim to enhance spectral resolution by suppressing the effects of homonuclear coupling interactions to turn multiplet signals into singlets. Such techniques typically work by selecting a subset of "active" nuclear spins to observe, and selectively inverting the remaining, "passive", spins to reverse the effects of coupling. Pure Shift Yielded by Chirp Excitation (PSYCHE) is one such method; it is relatively recent, but has already been successfully implemented in a range of different NMR experiments. Paradoxically, PSYCHE is one of the trickiest of pure shift NMR techniques to understand but one of the easiest to use. Here we offer some insights into theoretical and practical aspects of the method, and into the effects and importance of the experimental parameters. Some recent improvements that enhance the spectral purity of PSYCHE spectra will be presented, and some experimental frameworks including examples in 1D and 2D NMR spectroscopy, for the implementation of PSYCHE will be introduced. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Pure White Cell Aplasia and Necrotizing Myositis

    Directory of Open Access Journals (Sweden)

    Peter Geon Kim

    2016-01-01

    Full Text Available Pure white cell aplasia (PWCA is a rare hematologic disorder characterized by the absence of neutrophil lineages in the bone marrow with intact megakaryopoiesis and erythropoiesis. PWCA has been associated with autoimmune, drug-induced, and viral exposures. Here, we report a case of a 74-year-old female who presented with severe proximal weakness without pain and was found to have PWCA with nonspecific inflammatory necrotizing myositis and acute liver injury on biopsies. These findings were associated with a recent course of azithromycin and her daily use of a statin. Myositis improved on prednisone but PWCA persisted. With intravenous immunoglobulin and granulocyte-colony stimulating factor therapies, her symptoms and neutrophil counts improved and were sustained for months.

  6. Texture and Microtexture of Pure (6N and Commercially Pure Aluminum after Deformation by Extrusion with Forward-Backward Rotating Die (Kobo

    Directory of Open Access Journals (Sweden)

    Bieda M.

    2016-03-01

    Full Text Available Pure aluminium (6N and commercially pure aluminium (99.7 was deformed by KOBO method. Microstructure and texture of both materials after deformation was analyzed by means of scanning and transmission electron microscopy. Advanced methods of crystallographic orientations measurements like Electron Backscatter Diffraction - EBSD (SEM and microdiffraction (TEM was used. Grain size distribution and misorientation between grains in cross and longitudinal sections of the samples were analyzed. Differences in size and homogeneity of the grains were observed in both materials. Pure aluminium was characterized by larger grain size in both sections of extruded material. Whereas commercially pure aluminium reveals smaller grain size and more homogeneous and stable microstructure.

  7. Fabrication and evaluation of novel zeolite membranes to control the neoplastic activity and anti-tumoral drug treatments in human breast cancer cells. Part 1: Synthesis and characterization of Pure Zeolite Membranes and Mixed Matrix Membranes for adhesion and growth of cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tavolaro, Palmira, E-mail: p.tavolaro@unical.it [Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Cubo 4/c, 87036 Rende (Italy); Martino, Guglielmo [Department Di.B.E.S.T. (Biologia, Ecologia, Scienze della Terra), Unit of Physiology, University of Calabria, Cubo 4/c, 87036 Rende (Italy); Andò, Sebastiano [Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Cubo 4/c, 87036 Rende (Italy); Tavolaro, Adalgisa [Research Institute on Membrane Technology, Unit of Zeolite Membranes, ITM-CNR, University of Calabria, Cubo 17/c, 87036 Rende (Italy)

    2016-12-01

    Novel pure and hybrid zeolite membranes were prepared with appropriate different physicochemical characteristics such as frameworks, hydrophilicity, crystal size, chemical composition, acid-base properties (Point of Zero Charge, PZC) and surface morphology and used in inorganic cell/scaffold constructs. Because the control of cell interactions, as the adhesion, proliferation, remodelling and mobility, is important for differentiation and progression of tumors, this work focused on response of cancer cells adhered and grown on synthesized zeolite surfaces in order to study the influence of these scaffolds in controlled conditions. We have selected the MCF-7 and MDA-MB-231 human breast cancer cell line as model tumor cell lines. This study showed that all the zeolite membranes synthesized are excellent scaffolds because they are very selective materials to support the adhesion and growth of neoplastic cells. All zeolite scaffolds were characterized by FESEM, FTIR ATR, XRD, AFM, PZC and contact angle analyses. Cell adhesion, viability and morphology were measured by count, MTT assay and FESEM microphotography analysis, at various incubation times. - Highlights: • Novel pure and hybrid zeolite scaffolds were developed. • PZMs and MMMs were characterized and used with human cancer cells. • A systematic study of zeolite scaffolds influence on cell adhesion and morphology was performed. • The PZC value of zeolite membranes controls the cell-cell and scaffold-cell interactions.

  8. Fabrication and evaluation of novel zeolite membranes to control the neoplastic activity and anti-tumoral drug treatments in human breast cancer cells. Part 1: Synthesis and characterization of Pure Zeolite Membranes and Mixed Matrix Membranes for adhesion and growth of cancer cells

    International Nuclear Information System (INIS)

    Tavolaro, Palmira; Martino, Guglielmo; Andò, Sebastiano; Tavolaro, Adalgisa

    2016-01-01

    Novel pure and hybrid zeolite membranes were prepared with appropriate different physicochemical characteristics such as frameworks, hydrophilicity, crystal size, chemical composition, acid-base properties (Point of Zero Charge, PZC) and surface morphology and used in inorganic cell/scaffold constructs. Because the control of cell interactions, as the adhesion, proliferation, remodelling and mobility, is important for differentiation and progression of tumors, this work focused on response of cancer cells adhered and grown on synthesized zeolite surfaces in order to study the influence of these scaffolds in controlled conditions. We have selected the MCF-7 and MDA-MB-231 human breast cancer cell line as model tumor cell lines. This study showed that all the zeolite membranes synthesized are excellent scaffolds because they are very selective materials to support the adhesion and growth of neoplastic cells. All zeolite scaffolds were characterized by FESEM, FTIR ATR, XRD, AFM, PZC and contact angle analyses. Cell adhesion, viability and morphology were measured by count, MTT assay and FESEM microphotography analysis, at various incubation times. - Highlights: • Novel pure and hybrid zeolite scaffolds were developed. • PZMs and MMMs were characterized and used with human cancer cells. • A systematic study of zeolite scaffolds influence on cell adhesion and morphology was performed. • The PZC value of zeolite membranes controls the cell-cell and scaffold-cell interactions.

  9. Concurrence classes for general pure multipartite states

    International Nuclear Information System (INIS)

    Heydari, Hoshang

    2005-01-01

    We propose concurrence classes for general pure multipartite states based on an orthogonal complement of a positive operator-valued measure on quantum phase. In particular, we construct W m class, GHZ m , and GHZ m-1 class concurrences for general pure m-partite states. We give explicit expressions for W 3 and GHZ 3 class concurrences for general pure three-partite states and for W 4 , GHZ 4 and GHZ 3 class concurrences for general pure four-partite states

  10. Optimal purely functional priority queues

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Okasaki, Chris

    1996-01-01

    Brodal recently introduced the first implementation of imperative priority queues to support findMin, insert and meld in O(1) worst-case time, and deleteMin in O(log n) worst-case time. These bounds are asymptotically optimal among all comparison-based priority queues. In this paper, we adapt...... Brodal's data structure to a purely functional setting. In doing so, we both simplify the data structure and clarify its relationship to the binomial queues of Vuillemin, which support all four operations in O(log n) time. Specifically, we derive our implementation from binomial queues in three steps......: first, we reduce the running time of insert to O(1) by eliminating the possibility of cascading links; second, we reduce the running time of findMin to O(1) by adding a global root to hold the minimum element; and finally, we reduce the running time of meld to O(1) by allowing priority queues to contain...

  11. Musical notation reading in pure alexia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Wong, Yetta K.

    2017-01-01

    Pure alexia (PA) is an acquired reading disorder following lesions to left ventral temporo-occipital cortex. Patients with PA read slowly but correctly, and show an abnormal effect of word length on RTs. However, it is unclear how pure alexia may affect musical notation reading. We report a pure...

  12. Analysis of pure maple syrup consumers

    Science.gov (United States)

    Paul E. Sendak

    1974-01-01

    Virtually all of the pure maple syrup productim in the United States is in the northern states of Maine, Massachusetts, Michigan, New Hampshire, New York, Ohio, Pennsylvania, Vermont, and Wisconsin. Pure maple syrup users living in the maple production area and users living in other areas of the United States were asked a series of questions about their use of pure...

  13. Dual Target Search is Neither Purely Simultaneous nor Purely Successive.

    Science.gov (United States)

    Cave, Kyle R; Menneer, Tamaryn; Nomani, Mohammad S; Stroud, Michael J; Donnelly, Nick

    2017-08-31

    Previous research shows that visual search for two different targets is less efficient than search for a single target. Stroud, Menneer, Cave and Donnelly (2012) concluded that two target colours are represented separately based on modeling the fixation patterns. Although those analyses provide evidence for two separate target representations, they do not show whether participants search simultaneously for both targets, or first search for one target and then the other. Some studies suggest that multiple target representations are simultaneously active, while others indicate that search can be voluntarily simultaneous, or switching, or a mixture of both. Stroud et al.'s participants were not explicitly instructed to use any particular strategy. These data were revisited to determine which strategy was employed. Each fixated item was categorised according to whether its colour was more similar to one target or the other. Once an item similar to one target is fixated, the next fixated item is more likely to be similar to that target than the other, showing that at a given moment during search, one target is generally favoured. However, the search for one target is not completed before search for the other begins. Instead, there are often short runs of one or two fixations to distractors similar to one target, with each run followed by a switch to the other target. Thus, the results suggest that one target is more highly weighted than the other at any given time, but not to the extent that search is purely successive.

  14. Speeds in school zones.

    Science.gov (United States)

    2009-02-01

    School speed zones are frequently requested traffic controls for school areas, based on the common belief : that if the transportation agency would only install a reduced speed limit, then drivers would no longer : speed through the area. This resear...

  15. Pure Insulin Nanoparticle Agglomerates for Pulmonary Delivery

    Science.gov (United States)

    Bailey, Mark M.; Gorman, Eric M.; Munson, Eric J.; Berkland, Cory J.

    2009-01-01

    Diabetes is a set of diseases characterized by defects in insulin utilization, either through autoimmune destruction of insulin-producing cells (Type I) or insulin resistance (Type II). Treatment options can include regular injections of insulin, which can be painful and inconvenient, often leading to low patient compliance. To overcome this problem, novel formulations of insulin are being investigated, such as inhaled aerosols. Sufficient deposition of powder in the peripheral lung to maximize systemic absorption requires precise control over particle size and density, with particles between 1 and 5 μm in aerodynamic diameter being within the respirable range. Insulin nanoparticles were produced by titrating insulin dissolved at low pH up to the pI of the native protein, and were then further processed into microparticles using solvent displacement. Particle size, crystallinity, dissolution properties, structural stability, and bulk powder density were characterized. We have demonstrated that pure drug insulin microparticles can be produced from nanosuspensions with minimal processing steps without excipients, and with suitable properties for deposition in the peripheral lung. PMID:18959432

  16. Non-critical pure spinor superstrings

    International Nuclear Information System (INIS)

    Adam, Ido; Grassi, Pietro Antonio; Mazzucato, Luca; Oz, Yaron; Yankielowicz, Shimon

    2007-01-01

    We construct non-critical pure spinor superstrings in two, four and six dimensions. We find explicitly the map between the RNS variables and the pure spinor ones in the linear dilaton background. The RNS variables map onto a patch of the pure spinor space and the holomorphic top form on the pure spinor space is an essential ingredient of the mapping. A basic feature of the map is the requirement of doubling the superspace, which we analyze in detail. We study the structure of the non-critical pure spinor space, which is different from the ten-dimensional one, and its quantum anomalies. We compute the pure spinor lowest lying BRST cohomology and find an agreement with the RNS spectra. The analysis is generalized to curved backgrounds and we construct as an example the non-critical pure spinor type IIA superstring on AdS 4 with RR 4-form flux

  17. Mixtures of maximally entangled pure states

    Energy Technology Data Exchange (ETDEWEB)

    Flores, M.M., E-mail: mflores@nip.up.edu.ph; Galapon, E.A., E-mail: eric.galapon@gmail.com

    2016-09-15

    We study the conditions when mixtures of maximally entangled pure states remain entangled. We found that the resulting mixed state remains entangled when the number of entangled pure states to be mixed is less than or equal to the dimension of the pure states. For the latter case of mixing a number of pure states equal to their dimension, we found that the mixed state is entangled provided that the entangled pure states to be mixed are not equally weighted. We also found that one can restrict the set of pure states that one can mix from in order to ensure that the resulting mixed state is genuinely entangled. Also, we demonstrate how these results could be applied as a way to detect entanglement in mixtures of the entangled pure states with noise.

  18. Microstructural and mechanical properties of pure aluminum, 5083 and 7075 alloys joined by friction stir welding

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Selim Sarper [Celal Bayar Univ., Manisa, Muradiye (Turkey)

    2012-07-01

    In this study, microstructural and mechanical properties of pure aluminum, 5083 and 7075 alloys joined by friction stir welding were investigated. Hardness, tensile, bending and impact tests were applied to the welded samples. In addition, optical and SEM tests were carried out. The effects of welding speed on microstructure and mechanical properties were investigated in these materials. Then, the optimal conditions for friction stir welding were determined for pure aluminum, 5083 and 7075 alloys. The maximum hardness was observed for 7075 while the minimum hardness was observed for pure aluminum. (orig.)

  19. Proceedings of the Flat-plate Solar Array Project Research Forum on the High-speed Growth and Characterization of Crystals for Solar Cells

    Science.gov (United States)

    Dumas, K. A. (Editor)

    1984-01-01

    Theoretical and experimental phenomena, applications, and characterization including stress/strain and other problem areas that limit the rate of growth of crystals suitable for processing into efficient, cost-effective solar cells are discussed. Melt spinning, ribbon growth, rapid solidification, laser recrystallization, and ignot growth of silicon and metals are also discussed.

  20. Controlled synthesis of phase-pure zeolitic imidazolate framework Co-ZIF-9

    NARCIS (Netherlands)

    Öztürk, Z.; Hofmann, J.P.; Lutz, M.; Mazaj, M.; Zabukovec Logar, N.; Weckhuysen, B.M.

    2015-01-01

    The synthesis of phase-pure Co-ZIF-9, an important cobalt-based zeolitic imidazolate framework, could be achieved by modification of the reported synthesis procedure through pH adjustment of the starting synthesis mixture. The phase-pure Co-ZIF-9 material obtained has been characterized by a

  1. Measures for speed management.

    NARCIS (Netherlands)

    2009-01-01

    Measures for speed management are essential for limiting the negative effects of driving too fast and at inappropriate speeds. To begin with, safe and credible speed limits need to be determined. Dynamic and variable speed limits that take into account the current circumstances, such as weather

  2. Creep in commercially pure metals

    International Nuclear Information System (INIS)

    Nabarro, F.R.N.

    2006-01-01

    The creep of commercially pure polycrystalline metals under constant stress has four stages: a virtually instantaneous extension, decelerating Andrade β creep, almost steady-state Andrade κ creep, and an acceleration towards failure. Little is known about the first stage, and the fourth stage has been extensively reviewed elsewhere. The limited experimental evidence on the physical mechanism of the second stage is reviewed and a critical discussion is given of various theories of this stage. The dependence of strain rate on stress in the third, steady-state, period seems to fall into two regimes, a power law with an exponent of about 4-5, and a rather closely exponential law. The limits of the parameters within which a simple theory of the exponential dependence can be expected to be valid are discussed, and found to be compatible with experiments. Theories of the power-law dependence are discussed, and, appear to be unconvincing. The theoretical models do not relate closely to the metallographic and other physical observations. In view of the weakness of theory, experiments which may indicate the physical processes dominant in steady-state creep are reviewed. It is usually not clear whether they pertain to the power-law or the exponential regime. While the theories all assume that most of the deformation occurs homogeneously within the grains, most experimental observations point strongly to a large deformation at or close to the grain boundaries. However, a detailed study of dislocation processes in a single grain of polycrystalline foil strained in the electron microscope shows that most of the observed strain can be accounted for by the motion of single dislocations through the subgrain structure. There is no clear reconciliation of these two sets of observations. Grain-boundary sliding cannot occur without intragranular deformation. One or other process may dominate the overall deformation; the geometrically dominant process may not be the rate

  3. Wire-mesh sensor, ultrasound and high-speed videometry applied for the characterization of horizontal gas-liquid slug flow

    Science.gov (United States)

    Ofuchi, C. Y.; Morales, R. E. M.; Arruda, L. V. R.; Neves, F., Jr.; Dorini, L.; do Amaral, C. E. F.; da Silva, M. J.

    2012-03-01

    Gas-liquid flows occur in a broad range of industrial applications, for instance in chemical, petrochemical and nuclear industries. Correct understating of flow behavior is crucial for safe and optimized operation of equipments and processes. Thus, measurement of gas-liquid flow plays an important role. Many techniques have been proposed and applied to analyze two-phase flows so far. In this experimental research, data from a wire-mesh sensor, an ultrasound technique and high-speed camera are used to study two-phase slug flows in horizontal pipes. The experiments were performed in an experimental two-phase flow loop which comprises a horizontal acrylic pipe of 26 mm internal diameter and 9 m length. Water and air were used to produce the two-phase flow and their flow rates are separately controlled to produce different flow conditions. As a parameter of choice, translational velocity of air bubbles was determined by each of the techniques and comparatively evaluated along with a mechanistic flow model. Results obtained show good agreement among all techniques. The visualization of flow obtained by the different techniques is also presented.

  4. Fundamentals of the Pure Spinor Formalism

    CERN Document Server

    Hoogeveen, Joost

    2010-01-01

    This thesis presents recent developments within the pure spinor formalism, which has simplified amplitude computations in perturbative string theory, especially when spacetime fermions are involved. Firstly the worldsheet action of both the minimal and the non-minimal pure spinor formalism is derived from first principles, i.e. from an action with two dimensional diffeomorphism and Weyl invariance. Secondly the decoupling of unphysical states in the minimal pure spinor formalism is proved

  5. Environmental Stochasticity and the Speed of Evolution

    Science.gov (United States)

    Danino, Matan; Kessler, David A.; Shnerb, Nadav M.

    2018-03-01

    Biological populations are subject to two types of noise: demographic stochasticity due to fluctuations in the reproductive success of individuals, and environmental variations that affect coherently the relative fitness of entire populations. The rate in which the average fitness of a community increases has been considered so far using models with pure demographic stochasticity; here we present some theoretical considerations and numerical results for the general case where environmental variations are taken into account. When the competition is pairwise, fitness fluctuations are shown to reduce the speed of evolution, while under global competition the speed increases due to environmental stochasticity.

  6. Geometric derivation of the quantum speed limit

    International Nuclear Information System (INIS)

    Jones, Philip J.; Kok, Pieter

    2010-01-01

    The Mandelstam-Tamm and Margolus-Levitin inequalities play an important role in the study of quantum-mechanical processes in nature since they provide general limits on the speed of dynamical evolution. However, to date there has been only one derivation of the Margolus-Levitin inequality. In this paper, alternative geometric derivations for both inequalities are obtained from the statistical distance between quantum states. The inequalities are shown to hold for unitary evolution of pure and mixed states, and a counterexample to the inequalities is given for evolution described by completely positive trace-preserving maps. The counterexample shows that there is no quantum speed limit for nonunitary evolution.

  7. Pure Jauch-Piron states on von Neumann algebras

    International Nuclear Information System (INIS)

    Hamhalter, J.

    1993-01-01

    We study Jauch-Piron states and two-valued measures on von Neumann algebra. We prove as the main result that, under some set-theoretical assumption, a pure state of a von Neumann algebra A not containing a central abelian portion is Jauch-Piron if and only if it is σ-additive. Moreover, we show that this result holds for type I factor indenpendently on the set-theoretical axiomatics. As a consequence we obtain a lucid characterization of pure Jauch-Piron states on von Neumann algebras acting on a Hilbert space with real-nonmeasurable dimension (this can be viewed as a generalization of the paper). We also characterize the von Neumann algebras whose logic of projections is Jauch-Piron. Finally, we prove that every two-valued measure on the projection logic of A, where A contains no type I 2 central portion, has to be concentrated at an abelian direct summand of A. (orig.)

  8. Analytical Chemistry as Methodology in Modern Pure and Applied Chemistry

    OpenAIRE

    Honjo, Takaharu

    2001-01-01

    Analytical chemistry is an indispensable methodology in pure and applied chemistry, which is often compared to a foundation stone of architecture. In the home page of jsac, it is said that analytical chemistry is a learning of basic science, which treats the development of method in order to get usefull chemical information of materials by means of detection, separation, and characterization. Analytical chemistry has recently developed into analytical sciences, which treats not only analysis ...

  9. THE PURE RED BLOOD CELL APLASIA IN RENAL TRANSPLANT RECIPIENT

    OpenAIRE

    B. T. Dzumabaeva; L. S. Birjukova; L. B. Kaplanskaya; D. P. Maksimov

    2011-01-01

    The pure red blood cell aplasia of renal transplant recipients caused by parvovirus B19 (PB19) is characterized by persistent anemia which resistant to erythropoietin therapy, lack of reticulocytes, bone marrow hypoplasia, and clinically accompanied by severe recurrent bacterial, fungal and viral infection. In case of reactivation PB19 it is necessarv, first of all, eliminate the causes activation of this virus and to cancel or reduce the dose of drugs which depressed the normal hematopoiesis...

  10. Synthesis and characterization of pure and (Ce, Zr, Ag) doped mesoporous CuO-Fe{sub 2}O{sub 3} as highly efficient and stable nanocatalysts for CO oxidation at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Said, Abd El-Aziz A., E-mail: aasaid55@yahoo.com; Abd El-Wahab, Mohamed M.M.; Goda, Mohamed N.

    2016-12-30

    Highlights: • Highly active and stable Fe-Cu mixed oxides were prepared by co-precipitation method. • Addition of CuO to Fe{sub 2}O{sub 3} increases the chemisorbed oxygen, the conductivity and S{sub BET}. • Activation energy of CO oxidation significantly decreased via doping with foreign ions. - Abstract: A series of single and mixed oxide nanocatalysts of mesoporous CuO-Fe{sub 2}O{sub 3} with different CuO contents (1–50 wt.%) were prepared by a co-precipitation method and further promoted by trace amounts of CeO{sub 2}, ZrO{sub 2} and Ag{sub 2}O (0.1–0.5 wt.%) dopants. The original and calcined catalysts were characterized by TG, DTA, XRD, TEM, VSM, N{sub 2} sorption analysis, surface chemisorbed oxygen and DC electrical conductivity measurements. The catalytic performance of these nanocatalysts toward CO oxidation was studied using a conventional fixed bed flow type reactor. The results revealed that the addition of 1–20 wt.% CuO to Fe{sub 2}O{sub 3} monotonically increases the specific surface area, the amount of surface chemisorbed oxygen, electrical conductivity and catalytic activity of the nanocatalysts. In addition, the catalytic activity indicated that Fe-Cu mixed oxide nanocatalyst promoted with the three dopants (CeO{sub 2}, ZrO{sub 2} and Ag{sub 2}O) exhibited the highest catalytic activity with a total conversion of CO into CO{sub 2} at 100 °C. Moreover, the activation energy of CO oxidation decreased from 38.4 to 23.1 kJmol{sup −1} upon treating the catalyst containing 20 wt.% CuO with the three dopants. Finally the effects of various operational parameters were also studied.

  11. Nigeria Journal of Pure and Applied Physics

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics publishes papers of the highest quality and significance in specific areas of physics, pure and applied, as listed below. The journal content reflects core physics disciplines, but is also open to a broad range of topics whose central theme falls within the bounds of physics.

  12. Super-Maxwellian helium evaporation from pure and salty water

    International Nuclear Information System (INIS)

    Hahn, Christine; Kann, Zachary R.; Faust, Jennifer A.; Skinner, J. L.; Nathanson, Gilbert M.

    2016-01-01

    Helium atoms evaporate from pure water and salty solutions in super-Maxwellian speed distributions, as observed experimentally and modeled theoretically. The experiments are performed by monitoring the velocities of dissolved He atoms that evaporate from microjets of pure water at 252 K and 4–8.5 molal LiCl and LiBr at 232–252 K. The average He atom energies exceed the flux-weighted Maxwell-Boltzmann average of 2RT by 30% for pure water and 70% for 8.5m LiBr. Classical molecular dynamics simulations closely reproduce the observed speed distributions and provide microscopic insight into the forces that eject the He atoms from solution. Comparisons of the density profile and He kinetic energies across the water-vacuum interface indicate that the He atoms are accelerated by He–water collisions within the top 1-2 layers of the liquid. We also find that the average He atom kinetic energy scales with the free energy of solvation of this sparingly soluble gas. This free-energy difference reflects the steeply decreasing potential of mean force on the He atoms in the interfacial region, whose gradient is the repulsive force that tends to expel the atoms. The accompanying sharp decrease in water density suppresses the He–water collisions that would otherwise maintain a Maxwell-Boltzmann distribution, allowing the He atom to escape at high energies. Helium is especially affected by this reduction in collisions because its weak interactions make energy transfer inefficient

  13. Super-Maxwellian helium evaporation from pure and salty water

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Christine; Kann, Zachary R.; Faust, Jennifer A.; Skinner, J. L., E-mail: skinner@chem.wisc.edu, E-mail: nathanson@chem.wisc.edu; Nathanson, Gilbert M., E-mail: skinner@chem.wisc.edu, E-mail: nathanson@chem.wisc.edu [Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706 (United States)

    2016-01-28

    Helium atoms evaporate from pure water and salty solutions in super-Maxwellian speed distributions, as observed experimentally and modeled theoretically. The experiments are performed by monitoring the velocities of dissolved He atoms that evaporate from microjets of pure water at 252 K and 4–8.5 molal LiCl and LiBr at 232–252 K. The average He atom energies exceed the flux-weighted Maxwell-Boltzmann average of 2RT by 30% for pure water and 70% for 8.5m LiBr. Classical molecular dynamics simulations closely reproduce the observed speed distributions and provide microscopic insight into the forces that eject the He atoms from solution. Comparisons of the density profile and He kinetic energies across the water-vacuum interface indicate that the He atoms are accelerated by He–water collisions within the top 1-2 layers of the liquid. We also find that the average He atom kinetic energy scales with the free energy of solvation of this sparingly soluble gas. This free-energy difference reflects the steeply decreasing potential of mean force on the He atoms in the interfacial region, whose gradient is the repulsive force that tends to expel the atoms. The accompanying sharp decrease in water density suppresses the He–water collisions that would otherwise maintain a Maxwell-Boltzmann distribution, allowing the He atom to escape at high energies. Helium is especially affected by this reduction in collisions because its weak interactions make energy transfer inefficient.

  14. High-speed imaging and small-scale explosive characterization techniques to understand effects of primary blast-induced injury on nerve cell structure and function

    Science.gov (United States)

    Piehler, T.; Banton, R.; Zander, N.; Duckworth, J.; Benjamin, R.; Sparks, R.

    2018-01-01

    Traumatic brain injury (TBI) is often associated with blast exposure. Even in the absence of penetrating injury or evidence of tissue injury on imaging, blast TBI may trigger a series of neural/glial cellular and functional changes. Unfortunately, the diagnosis and proper treatment of mild traumatic brain injury (mTBI) caused by explosive blast is challenging, as it is not easy to clinically distinguish blast from non-blast TBI on the basis of patient symptoms. Damage to brain tissue, cell, and subcellular structures continues to occur slowly and in a manner undetectable by conventional imaging techniques. The threshold shock impulse levels required to induce damage and the cumulative effects upon multiple exposures are not well characterized. Understanding how functional and structural damage from realistic blast impact at cellular and tissue levels at variable timescales after mTBI events may be vital for understanding this injury phenomenon and for linking mechanically induced structural changes with measurable effects on the nervous system. Our working hypothesis is that there is some transient physiological dysfunction occurring at cellular and subcellular levels within the central nervous system due to primary blast exposure. We have developed a novel in vitro indoor experimental system that uses real military explosive charges to more accurately represent military blast exposure and to probe the effects of primary explosive blast on dissociated neurons. We believe this system offers a controlled experimental method to analyze and characterize primary explosive blast-induced cellular injury and to understand threshold injury phenomenon. This paper will also focus on the modeling aspect of our work and how it relates to the experimental work.

  15. Fracture probability properties of pure and cantilever bending fatigue of STS304 steel

    International Nuclear Information System (INIS)

    Roh, Sung Kuk; Park, Dae Hyun; Jeong, Soon Uk

    2001-01-01

    Big accidents of flyings, vessel, subways, gas equipments, buildings and bridge happens frequently. Therefore many people are suffering harm of property. The destruction cause of marcaine components is almost accused by fatigue. This study is test for STS304 specimen using pure and cantilever bending state. Rounded and notched specimen including fracture surface investigation was comparatively experimented, fatigue life according to degree of surface finishing was examined. Fatigue fracture probability of notched canilever specimens were predicted by P-S-N curve, median rank and Weibull distribution. And at the relation with the rotational speed and stress, the fatigue life of the test specimen was higher at high speed than low speed

  16. Speed management program plan.

    Science.gov (United States)

    2014-05-01

    Changing public attitudes regarding speeding and speed management will require a comprehensive and concerted effort, involving a wide variety of strategies. This plan identifies six primary focus areas: : A. Data and Data-Driven Approaches, : B. Rese...

  17. Small portable speed calculator

    Science.gov (United States)

    Burch, J. L.; Billions, J. C.

    1973-01-01

    Calculator is adapted stopwatch calibrated for fast accurate measurement of speeds. Single assembled unit is rugged, self-contained, and relatively inexpensive to manufacture. Potential market includes automobile-speed enforcement, railroads, and field-test facilities.

  18. Electric vehicle speed control

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, W.R.; Mc Auliffe, G.N.; Schlageter, G.A.

    1987-06-23

    This patent describes an electric vehicle driven by a DC motor. The vehicle has a field winding, an electric resistance element in circuit with the field winding, a switch in the circuit operative when closed to place. The element in parallel with the field winding weakens the field and increases potential motor speed. Also are relay means for operating the switch, means to determine motor speed, computer means for determining whether the motor speed is increasing or decreasing, and means for operating the relay means to close the switch at a first speed. If the motor speed is increased, it actuates the switch at a second speed lower than the first speed but only if switch has been closed previously and motor speed is decreasing.

  19. Perspectives on the Pure-Tone Audiogram.

    Science.gov (United States)

    Musiek, Frank E; Shinn, Jennifer; Chermak, Gail D; Bamiou, Doris-Eva

    The pure-tone audiogram, though fundamental to audiology, presents limitations, especially in the case of central auditory involvement. Advances in auditory neuroscience underscore the considerably larger role of the central auditory nervous system (CANS) in hearing and related disorders. Given the availability of behavioral audiological tests and electrophysiological procedures that can provide better insights as to the function of the various components of the auditory system, this perspective piece reviews the limitations of the pure-tone audiogram and notes some of the advantages of other tests and procedures used in tandem with the pure-tone threshold measurement. To review and synthesize the literature regarding the utility and limitations of the pure-tone audiogram in determining dysfunction of peripheral sensory and neural systems, as well as the CANS, and to identify other tests and procedures that can supplement pure-tone thresholds and provide enhanced diagnostic insight, especially regarding problems of the central auditory system. A systematic review and synthesis of the literature. The authors independently searched and reviewed literature (journal articles, book chapters) pertaining to the limitations of the pure-tone audiogram. The pure-tone audiogram provides information as to hearing sensitivity across a selected frequency range. Normal or near-normal pure-tone thresholds sometimes are observed despite cochlear damage. There are a surprising number of patients with acoustic neuromas who have essentially normal pure-tone thresholds. In cases of central deafness, depressed pure-tone thresholds may not accurately reflect the status of the peripheral auditory system. Listening difficulties are seen in the presence of normal pure-tone thresholds. Suprathreshold procedures and a variety of other tests can provide information regarding other and often more central functions of the auditory system. The audiogram is a primary tool for determining type

  20. Synthesis and optical characterization of ZrO{sub 2} pure and doped with Er{sup 3+} ions for use as thermoluminescent dosimeter; Sintesis y caracterizacion optica de ZrO{sub 2} puro y dopado con iones Er{sup 3+} para su aplicacion como dosimetro termoluminiscente

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez E, R.; Sosa F, R.; Arrieta C, A. M., E-mail: ralf_gutierrez@yahoo.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Departamento de Fisica, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2015-10-15

    Full text: There are different natural minerals and synthetic inorganic compounds exhibiting the phenomenon of thermoluminescence (Tl); however only part of them meet the requirements for use as Tl dosimeters. In this research the synthesis and characterization of ZrO{sub 2} pure and doped with Er{sup 3+} ions are presented, at a concentration of 0.5 % mol prepared by the sol-gel method in monolithic way and transparent for its possible application as thermoluminescent dosimeter. The materials are characterized by absorption spectroscopy, emission and excitation in the region of UV-Vis-Nir, in which spectra corresponding to ZrO{sub 2} and characteristic bands of Er{sup 3+} doped are observed, identifying the mechanisms of energy transfer for the emitted radiation as one of the most important points in the Tl materials design. It was observed that the threshold dose detection and accuracy of measurements depend on the efficiency of energy conversion. In addition an analysis by scanning electron microscopy, EDS and X-ray diffraction on the morphologic and spectroscopic changes caused by the reduction of organic material is presented. These were carried out in two different drying processes: at room temperature and annealing at 500 degrees C. All these physical and chemical properties are crucial in deciding its application in dosimetry of ionizing radiation. (Author)

  1. Wolf-Hirschhorn (4p-) syndrome: prenatal diagnosis, molecular cytogenetic characterization and association with a 1.2-Mb microduplication at 8p22-p21.3 and a 1.1-Mb microduplication at 10p15.3 in a fetus with an apparently pure 4p deletion.

    Science.gov (United States)

    Chen, Chih-Ping; Su, Yi-Ning; Chen, Yi-Yung; Su, Jun-Wei; Chern, Schu-Rern; Chen, Yu-Ting; Chen, Wen-Lin; Chen, Li-Feng; Wang, Wayseen

    2011-12-01

    To present prenatal diagnosis and molecular cytogenetic characterization of Wolf-Hirschhorn syndrome (WHS) associated with microduplications at 8p and 10p in a fetus with an apparently pure 4p deletion. A 35-year-old gravida 2, para 1 woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Her husband was 38 years of age. There was no family history of congenital malformations. Amniocentesis revealed a karyotype of 46,XY,del(4p16.1). The parental karyotypes were normal. Array comparative genomic hybridization (aCGH) analysis revealed a 6.5-Mb deletion at 4p16.3-p16.1, a 1.2-Mb microduplication at 8p22-p21.3, and a 1.1-Mb microduplication at 10p15.3, or arr cgh 4p16.3p16.1 (0-6,531,998 bp)×1, 8p22p21.3 (18,705,388-19,940,445 bp)×3, 10p15.3 (0-1,105,065 bp)×3. Polymorphic DNA marker analysis confirmed a paternal origin of 4p deletion. Prenatal ultrasound revealed facial dysmorphism and hypospadias. The aCGH analysis of the parents revealed no genomic imbalance. Fluorescence in situ hybridization study showed an unbalanced reciprocal translocation between chromosomes 4 and 10 at bands 4p16.1 and 10p15.3. The cytogenetic result, thus, was 46,XY,der(4)t(4;10)(p16.1;p15.3),dup(8)(p21.3p22). The parents elected to terminate the pregnancy, and a 470-g malformed fetus was delivered. The present case provides evidence that an apparently pure 4p deletion can be associated with subtle chromosome imbalances in other chromosomes. Copyright © 2011. Published by Elsevier B.V.

  2. Experimental and numerical assessment of ignition delay period for pure diesel and biodiesel B20

    Science.gov (United States)

    Aldhaidhawi, Mohanad; Brabec, Marek; Lucian, Miron; Chiriac, Radu; Bădescu, Viorel

    2017-10-01

    The ignition delay period for a compression ignition engine fueled alternatively with pure diesel and with biodiesel B20 has been experimentally and numerically investigated. The engine was operated under full load conditions for two speeds, 1400 rpm speed for maximum brake torque and 2400 rpm speed for maximum brake power. Different parameters suggested as important to define the start of combustion have been considered before the acceptance of a certain evaluation technique of ignition delay. Correlations between these parameters were analyzed and concluded about the best method to identify the start of combustion. The experimental results were further compared with the ignition delay predicted by some correlations. The results showed that the determined ignition delays are in good agreement with those of the Arrhenius type expressions for pure diesel fuel, while for biodiesel B20 the correlation results are significantly different than the experimental results.

  3. Pure spinor integration from the collating formula

    International Nuclear Information System (INIS)

    Grassi, P.A.; Sommovigo, L.

    2011-01-01

    We use the technique developed by Becchi and Imbimbo to construct a well-defined BRST-invariant path integral formulation of pure spinor amplitudes. The space of pure spinors can be viewed from the algebraic geometry point of view as a collection of open sets where the constraints can be solved and a set of free and independent variables can be defined. On the intersections of those open sets, the functional measure jumps and one has to add boundary terms to construct a well-defined path integral. The result is the definition of the pure spinor integration measure constructed in terms of differential forms on each single patch.

  4. Conformal pure radiation with parallel rays

    International Nuclear Information System (INIS)

    Leistner, Thomas; Paweł Nurowski

    2012-01-01

    We define pure radiation metrics with parallel rays to be n-dimensional pseudo-Riemannian metrics that admit a parallel null line bundle K and whose Ricci tensor vanishes on vectors that are orthogonal to K. We give necessary conditions in terms of the Weyl, Cotton and Bach tensors for a pseudo-Riemannian metric to be conformal to a pure radiation metric with parallel rays. Then, we derive conditions in terms of the tractor calculus that are equivalent to the existence of a pure radiation metric with parallel rays in a conformal class. We also give analogous results for n-dimensional pseudo-Riemannian pp-waves. (paper)

  5. Tensor modes in pure natural inflation

    Science.gov (United States)

    Nomura, Yasunori; Yamazaki, Masahito

    2018-05-01

    We study tensor modes in pure natural inflation [1], a recently-proposed inflationary model in which an axionic inflaton couples to pure Yang-Mills gauge fields. We find that the tensor-to-scalar ratio r is naturally bounded from below. This bound originates from the finiteness of the number of metastable branches of vacua in pure Yang-Mills theories. Details of the model can be probed by future cosmic microwave background experiments and improved lattice gauge theory calculations of the θ-angle dependence of the vacuum energy.

  6. Pure Phase Solubility Limits: LANL

    International Nuclear Information System (INIS)

    C. Stockman

    2001-01-01

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO 2 partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility products

  7. Pure Phase Solubility Limits: LANL

    Energy Technology Data Exchange (ETDEWEB)

    C. Stockman

    2001-01-26

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO{sub 2} partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility

  8. Speed in Acquisitions

    DEFF Research Database (Denmark)

    Meglio, Olimpia; King, David R.; Risberg, Annette

    2017-01-01

    The advantage of speed is often invoked by academics and practitioners as an essential condition during post-acquisition integration, frequently without consideration of the impact earlier decisions have on acquisition speed. In this article, we examine the role speed plays in acquisitions across...... the acquisition process using research organized around characteristics that display complexity with respect to acquisition speed. We incorporate existing research with a process perspective of acquisitions in order to present trade-offs, and consider the influence of both stakeholders and the pre......-deal-completion context on acquisition speed, as well as the organization’s capabilities to facilitating that speed. Observed trade-offs suggest both that acquisition speed often requires longer planning time before an acquisition and that associated decisions require managerial judgement. A framework for improving...

  9. Control aspects of quantum computing using pure and mixed states

    Science.gov (United States)

    Schulte-Herbrüggen, Thomas; Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Khaneja, Navin; Glaser, Steffen J.

    2012-01-01

    Steering quantum dynamics such that the target states solve classically hard problems is paramount to quantum simulation and computation. And beyond, quantum control is also essential to pave the way to quantum technologies. Here, important control techniques are reviewed and presented in a unified frame covering quantum computational gate synthesis and spectroscopic state transfer alike. We emphasize that it does not matter whether the quantum states of interest are pure or not. While pure states underly the design of quantum circuits, ensemble mixtures of quantum states can be exploited in a more recent class of algorithms: it is illustrated by characterizing the Jones polynomial in order to distinguish between different (classes of) knots. Further applications include Josephson elements, cavity grids, ion traps and nitrogen vacancy centres in scenarios of closed as well as open quantum systems. PMID:22946034

  10. Control aspects of quantum computing using pure and mixed states.

    Science.gov (United States)

    Schulte-Herbrüggen, Thomas; Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Khaneja, Navin; Glaser, Steffen J

    2012-10-13

    Steering quantum dynamics such that the target states solve classically hard problems is paramount to quantum simulation and computation. And beyond, quantum control is also essential to pave the way to quantum technologies. Here, important control techniques are reviewed and presented in a unified frame covering quantum computational gate synthesis and spectroscopic state transfer alike. We emphasize that it does not matter whether the quantum states of interest are pure or not. While pure states underly the design of quantum circuits, ensemble mixtures of quantum states can be exploited in a more recent class of algorithms: it is illustrated by characterizing the Jones polynomial in order to distinguish between different (classes of) knots. Further applications include Josephson elements, cavity grids, ion traps and nitrogen vacancy centres in scenarios of closed as well as open quantum systems.

  11. Mechanochemical synthesis and characterization of pure Co2B ...

    Indian Academy of Sciences (India)

    mical process Master Thesis (Ankara: Middle East Technical. University). [40] Can M M, Özcan S, Ceylan A and Fırat T 2010 Mater. Sci. Eng. B 172 72. [41] Avar B and Özcan S 2015 J. Alloys Compd. 650 53. [42] Simsek T 2014 Investigation of the zirconium diboride nanocrystal coated different materials mechanic and ...

  12. Preparation and Characterization of Pure Organic Dielectric Composites for Capacitors

    Directory of Open Access Journals (Sweden)

    Mao Xin

    2018-01-01

    Full Text Available This work reports the excellent dielectric composites were prepared from polyimide (PI and poly(vinylidene fluoride (PVDF via solution blending and thermal imidization or chemical imidization. The dielectric and thermal properties of the composites were studied. Results indicated that the dielectric properties of the composites synthesized by these two methods were enhanced through the introduction of PVDF, and the composites exhibited excellent thermal stability. Compared to the thermal imidization, the composites prepared by chemical imidization exhibited superior dielectric properties. This study demonstrated that the PI/PVDF composites were potential dielectric materials in the field of electronics.

  13. EBIC and DLTS characterization of pure Si crystals

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Possibilities of measurements of low defect concentration in Si by the electrical methods are discussed. ... of highly integrated circuits, the tolerable concentrations .... centrations in p-type irradiated FZ–Si after WCE and sub- sequent ...

  14. Characterization of pure and copper-doped iron tartrate crystals ...

    Indian Academy of Sciences (India)

    FTIR), .... rotational and vibrational energy levels of the ground electronic energy state. ..... Vidyalaya College of Arts and Science, Coimbatore, India for the timely help ... Head, Marketing, Pricol Castings Ltd., Coimbatore for the support during the ...

  15. Growth and characterization of pure and lithium doped strontium ...

    Indian Academy of Sciences (India)

    TECS

    Abstract. The effect of lithium ion as dopant on the size and transparency of strontium tartrate tetrahydrate. (SrC4H4O6⋅4H2O) crystals are presented in this paper. Growth of single crystals of undoped and lithium doped strontium tartrate tetrahydrate by controlled diffusion of strontium nitrate into the gel charged with.

  16. Processing and characterization of pure cordierite and zirconia ...

    Indian Academy of Sciences (India)

    3Department of Physics, College of Engineering and Technology, Tiruchirappalli 620 024, ... conventional method described for synthesizing cordierite ... chemical inhomogenity. .... determined by applying the Archimedes principle and poros-.

  17. Preparation and characterization of free-standing pure porphyrin ...

    Indian Academy of Sciences (India)

    Wintec

    is not extensive unlike inorganic, metallic or semicon- ductor nanoparticle. Organic nanoparticles are of in- terest not only because they represent an intermediate situation between single molecules and bulk materi- als, representing a multichromophoric system but also they offer potential applications in science and tech-.

  18. Lectures on the theory of pure motives

    CERN Document Server

    Murre, Jacob P; A, Chris

    2013-01-01

    The theory of motives was created by Grothendieck in the 1960s as he searched for a universal cohomology theory for algebraic varieties. The theory of pure motives is well established as far as the construction is concerned. Pure motives are expected to have a number of additional properties predicted by Grothendieck's standard conjectures, but these conjectures remain wide open. The theory for mixed motives is still incomplete. This book deals primarily with the theory of pure motives. The exposition begins with the fundamentals: Grothendieck's construction of the category of pure motives and examples. Next, the standard conjectures and the famous theorem of Jannsen on the category of the numerical motives are discussed. Following this, the important theory of finite dimensionality is covered. The concept of Chow-K�nneth decomposition is introduced, with discussion of the known results and the related conjectures, in particular the conjectures of Bloch-Beilinson type. We finish with a chapter on relative m...

  19. Global Journal of Pure and Applied Sciences

    African Journals Online (AJOL)

    Global Journal of Pure and Applied Sciences is a multi-disciplinary specialist journal ... research in Biological Science, Agricultural Sciences, Chemical Sciences, ... Comparative study of the physicochemical and bacteriological qualities of ...

  20. Expander graphs in pure and applied mathematics

    OpenAIRE

    Lubotzky, Alexander

    2012-01-01

    Expander graphs are highly connected sparse finite graphs. They play an important role in computer science as basic building blocks for network constructions, error correcting codes, algorithms and more. In recent years they have started to play an increasing role also in pure mathematics: number theory, group theory, geometry and more. This expository article describes their constructions and various applications in pure and applied mathematics.

  1. Refurbishment of JMTR pure water facility

    International Nuclear Information System (INIS)

    Asano, Norikazu; Hanakawa, Hiroki; Kusunoki, Hidehiko; Satou, Shinichi

    2012-05-01

    In the refurbishment of JMTR, facilities were classified into which (1) were all updated, (2) were partly updated, and (3) were continuance used by the considerations of the maintenance history, the change parts availability and the latest technology. The JMTR pure water facility was classified into all updated facility based on the consideration. The Update construction was conducted in between FY2007 and FY2008. The refurbishment of JMTR pure water facility is summarized in this report. (author)

  2. Nanocrystalline Ni-Co Alloy Synthesis by High Speed Electrodeposition

    OpenAIRE

    Idris, Jamaliah; Christian, Chukwuekezie; Gaius, Eyu

    2013-01-01

    Electrodeposition of nanocrystals is economically and technologically viable production path for the synthesis of pure metals and alloys both in coatings and bulk form. The study presents nanocrystalline Ni-Co alloy synthesis by high speed electrodeposition. Nanocrystalline Ni-Co alloys coatings were prepared by direct current (DC) and deposited directly on steel and aluminum substrates without any pretreatment, using high speed electrodeposition method. The influence of the electrolysis par...

  3. Speed and income

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2005-01-01

    The relationship between speed and income is established in a microeconomic model focusing on the trade-off between travel time and the risk of receiving a penalty for exceeding the speed limit. This is used to determine when a rational driver will choose to exceed the speed limit. The relationship...... between speed and income is found again in the empirical analysis of a cross-sectional dataset comprising 60,000 observations of car trips. This is used to perform regressions of speed on income, distance travelled, and a number of controls. The results are clearly statistically significant and indicate...... an average income elasticity of speed of 0.02; it is smaller at short distances and about twice as large at the longest distance investigated of 200 km....

  4. High speed atom source

    International Nuclear Information System (INIS)

    Hoshino, Hitoshi.

    1990-01-01

    In a high speed atom source, since the speed is not identical between ions and electrons, no sufficient neutralizing effect for ionic rays due to the mixing of the ionic rays and the electron rays can be obtained failing to obtain high speed atomic rays at high density. In view of the above, a speed control means is disposed for equalizing the speed of ions forming ionic rays and the speed of electrons forming electron rays. Further, incident angle of the electron rays and/or ionic rays to a magnet or an electrode is made variable. As a result, the relative speed between the ions and the electrons to the processing direction is reduced to zero, in which the probability of association between the ions and the electrons due to the coulomb force is increased to improve the neutralizing efficiency to easily obtain fine and high density high speed electron rays. Further, by varying the incident angle, a track capable of obtaining an ideal mixing depending on the energy of the neutralized ionic rays is formed. Since the high speed electron rays has such high density, they can be irradiated easily to the minute region of the specimen. (N.H.)

  5. Computer ray tracing speeds.

    Science.gov (United States)

    Robb, P; Pawlowski, B

    1990-05-01

    The results of measuring the ray trace speed and compilation speed of thirty-nine computers in fifty-seven configurations, ranging from personal computers to super computers, are described. A correlation of ray trace speed has been made with the LINPACK benchmark which allows the ray trace speed to be estimated using LINPACK performance data. The results indicate that the latest generation of workstations, using CPUs based on RISC (Reduced Instruction Set Computer) technology, are as fast or faster than mainframe computers in compute-bound situations.

  6. Study of speed endurance middle distance runners

    Directory of Open Access Journals (Sweden)

    R.V. Golovaschenko

    2013-12-01

    Full Text Available Purpose : To investigate the boost performance speed endurance runners who specialize in middle-distance running . Material and methods : The study involved team members Vinnytsia region in an amount of 44 people, whose average age was 20,2 ± 2,1 years. Classes are held during the 21-day mesocycle, 5 times a week, twice a day. Things were aimed at enhancing the development of indicators of special speed endurance. Results : The dynamics of the running speed of the model segments that characterize speed endurance athletes. Proved that the improved running 400 meter intervals helps reduce travel time competitive distance of 1500 meters. Conclusion : The use of the program contributes to higher speed endurance, which determines the result in the women's 1,500 meters.

  7. Characterization of high speed synthetic jet actuators

    Science.gov (United States)

    Pikcilingis, Lucia

    Over the last 20 years, synthetic jets have been studied as a means for aerodynamic active flow control. Specifically, synthetic jets provide momentum transfer with zero-net mass flux, which has been proven to be effective for controlling flow fields. A synthetic jet is created by the periodic formation of vortex rings at its orifice due to the periodic motion of a piezoelectric disk(s). The present study seeks to optimize the performance of a synthetic jet actuator by utilizing different geometrical parameters such as disk thickness, orifice width and length, cavity height and cavity diameter, and different input parameters such as driving voltage and frequency. Two apparatuses were used with a cavity diameter of either 80 mm or 160 mm. Piezoelectric-based disks were provided by the Mide Corporation. Experiments were conducted using several synthetic jet apparatuses designed for various geometrical parameters utilizing a dual disk configuration. Velocity and temperature measurements were acquired at the center of the synthetic jet orifice using a temperature compensated hotwire and thermocouple probe. The disk(s) displacement was measured at the center of the disk with a laser displacement sensor. It was shown that the synthetic jets, having the 80 mm cavity diameter, are capable of exceeding peak velocities of 200 m/s with a relatively large orifice of dimensions AR = 12, hc* = 3, and hn* = 4. In addition, the conditions at which the disks were manufactured had minimal effect on the performance of the jet, except for the pair with overnight resting time as opposed to less than an hour resting time for the control units. Altering the tab style of the disks, where the tab allows the electrical circuit to be exposed for external power connection, showed that a thin fragile tab versus a tab of the same thickness as the disk has minimal effect on the performance but affects the durability of the disk due to the fragility or robustness of the tab. The synthetic jets, having a 160 mm cavity diameter, yielded jet velocities greater than 300 m/s. Altering the clamping conditions, at which the disks are clamped, showed that increasing the number of clamping points where the disks are clamped, improved the performance of the jet. Coupling this with a flexible clamping boundary condition yielded the best performing jets. Fatigue tests were conducted for both apparatuses using several different disk designs. These tests showed that there is a degradation of the disks that causes the jet performance to decay and eventually cause a fracture in the disk. It is apparent from this work that, though the conditions at which the disks are manufactured have a small effect on performance, the disks do exhibit a threshold where beyond it the performance decays. Though desired jet velocities and momentums are achievable, the abnormality of the disks needs to be addressed before applying the actuator to practical situations. As this research continues, the synthetic jet actuator will become more robust and reliable to be an effective and reliable source of active flow control.

  8. Unilateral pure trigeminal motor nerve neuropathy: A rare case report

    Directory of Open Access Journals (Sweden)

    Nishant K Srivastava

    2014-01-01

    Full Text Available Unilateral pure trigeminal motor nerve neuropathy is an extremely rare and unique condition, characterized by atrophy of the muscles, innervated by the motor branch of the trigeminal nerve. We report such a case in a 25-year-old male patient. The diagnosis was made on the basis of clinical and radiological examinations. Magnetic Resonance Imaging (MRI proved to be the key for establishing the diagnosis, which showed atrophy and fatty infiltration over the affected side of the muscles of mastication. We were unable to establish the cause of the condition even after performing a brain MRI.

  9. Substructure and electrical resistivity analyses of pure tungsten sheet

    International Nuclear Information System (INIS)

    Trybus, C.L.; Sellers, C.H.; Anderl, R.A.

    1991-01-01

    The substructure of pure tungsten sheet (0.025 mm thick) is examined and quantified by transmission electron microscopy (TEM). Dislocation populations and arrangements are evaluated for as-worked and various annealed conditions of the tungsten sheet. The worked (rolled) tungsten substructure was nonhomogeneous, consisting of areas of very high and low dislocation densities. These results are correlated to resistivity measurements of the tungsten sheet following thermal cycling to 1200 degrees C to determine the substructural changes as a function of temperature. The comparison between the two characterization techniques is used to examine the relationship between structural and electronic properties in tungsten. 15 refs., 6 figs., 2 tabs

  10. Hexagonal ice in pure water and biological NMR samples

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Thomas; Gath, Julia; Hunkeler, Andreas; Ernst, Matthias, E-mail: maer@ethz.ch [ETH Zurich, Physical Chemistry (Switzerland); Böckmann, Anja, E-mail: a.bockmann@ibcp.fr [UMR 5086 CNRS, Université de Lyon 1, Institut de Biologie et Chimie des Protéines (France); Meier, Beat H., E-mail: beme@ethz.ch [ETH Zurich, Physical Chemistry (Switzerland)

    2017-01-15

    Ice, in addition to “liquid” water and protein, is an important component of protein samples for NMR spectroscopy at subfreezing temperatures but it has rarely been observed spectroscopically in this context. We characterize its spectroscopic behavior in the temperature range from 100 to 273 K, and find that it behaves like pure water ice. The interference of magic-angle spinning (MAS) as well as rf multiple-pulse sequences with Bjerrum-defect motion greatly influences the ice spectra.

  11. THE PURE RED BLOOD CELL APLASIA IN RENAL TRANSPLANT RECIPIENT

    Directory of Open Access Journals (Sweden)

    B. T. Dzumabaeva

    2011-01-01

    Full Text Available The pure red blood cell aplasia of renal transplant recipients caused by parvovirus B19 (PB19 is characterized by persistent anemia which resistant to erythropoietin therapy, lack of reticulocytes, bone marrow hypoplasia, and clinically accompanied by severe recurrent bacterial, fungal and viral infection. In case of reactivation PB19 it is necessarv, first of all, eliminate the causes activation of this virus and to cancel or reduce the dose of drugs which depressed the normal hematopoiesis germs, thus to reduce the pancytopenia associating complications in this population. 

  12. Improved Algorithms Speed It Up for Codes

    International Nuclear Information System (INIS)

    Hazi, A

    2005-01-01

    Huge computers, huge codes, complex problems to solve. The longer it takes to run a code, the more it costs. One way to speed things up and save time and money is through hardware improvements--faster processors, different system designs, bigger computers. But another side of supercomputing can reap savings in time and speed: software improvements to make codes--particularly the mathematical algorithms that form them--run faster and more efficiently. Speed up math? Is that really possible? According to Livermore physicist Eugene Brooks, the answer is a resounding yes. ''Sure, you get great speed-ups by improving hardware,'' says Brooks, the deputy leader for Computational Physics in N Division, which is part of Livermore's Physics and Advanced Technologies (PAT) Directorate. ''But the real bonus comes on the software side, where improvements in software can lead to orders of magnitude improvement in run times.'' Brooks knows whereof he speaks. Working with Laboratory physicist Abraham Szoeke and others, he has been instrumental in devising ways to shrink the running time of what has, historically, been a tough computational nut to crack: radiation transport codes based on the statistical or Monte Carlo method of calculation. And Brooks is not the only one. Others around the Laboratory, including physicists Andrew Williamson, Randolph Hood, and Jeff Grossman, have come up with innovative ways to speed up Monte Carlo calculations using pure mathematics

  13. Pure states of general quantum-mechanical systems as Kaehler bundles

    International Nuclear Information System (INIS)

    Abbati, M.C.; Cirelli, R.; Lanzavecchia, P.; Mania, A.

    1984-01-01

    Pure states of general quantum systems in the Csup(*)-algebraic approach are endowed with a structure both of Kaehler manifold and of projective bundle with uniformity on the total space. The former structure gives a geometric interpretation of transition probabilities and Wigner theorem. The latter is a finer structure which determines Csup(*)-algebras up to sup(*)-isomorphisms. Pure states of Csup(*)-algebras with continuous trace among projective bundles with uniformity are characterized

  14. On the Computation and Applications of Bessel Functions with Pure Imaginary Indices

    OpenAIRE

    Matyshev, A. A.; Fohtung, E.

    2009-01-01

    Bessel functions with pure imaginary index (order) play an important role in corpuscular optics where they govern the dynamics of charged particles in isotrajectory quadrupoles. Recently they were found to be of great importance in semiconductor material characterization as they are manifested in the strain state of crystalline material. A new algorithm which can be used for the computation of the normal and modifed Bessel functions with pure imaginary index is proposed. The developed algorit...

  15. Engineering arbitrary pure and mixed quantum states

    International Nuclear Information System (INIS)

    Pechen, Alexander

    2011-01-01

    Controlled manipulation by atomic- and molecular-scale quantum systems has attracted a lot of research attention in recent years. A fundamental problem is to provide deterministic methods for controlled engineering of arbitrary quantum states. This work proposes a deterministic method for engineering arbitrary pure and mixed states of a wide class of quantum systems. The method exploits a special combination of incoherent and coherent controls (incoherent and coherent radiation) and has two properties which are specifically important for manipulating by quantum systems: it realizes the strongest possible degree of their state control, complete density matrix controllability, meaning the ability to steer arbitrary pure and mixed initial states into any desired pure or mixed final state, and it is all-to-one, such that each particular control transfers all initial system states into one target state.

  16. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, G.H.; Sterken, E.

    2002-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for bothmen and women. The historical data show that it is likely that the relation betweenskating speed and distance of the various events is non-linear and converges to a limitvalue. We pay special attention to technical

  17. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, Gerard H.; Sterken, Elmer

    2001-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for both men and women. The historical data show that it is likely that the relation between skating speed and distance of the various events is non-linear and converges to a limit value. We pay special attention to

  18. Topological M Theory from Pure Spinor Formalism

    CERN Document Server

    Grassi, P A; Grassi, Pietro Antonio; Vanhove, Pierre

    2005-01-01

    We construct multiloop superparticle amplitudes in 11d using the pure spinor formalism. We explain how this construction reduces to the superparticle limit of the multiloop pure spinor superstring amplitudes prescription. We then argue that this construction points to some evidence for the existence of a topological M theory based on a relation between the ghost number of the full-fledged supersymmetric critical models and the dimension of the spacetime for topological models. In particular, we show that the extensions at higher orders of the previous results for the tree and one-loop level expansion for the superparticle in 11 dimensions is related to a topological model in 7 dimensions.

  19. Quasinormal modes in pure de Sitter spacetimes

    International Nuclear Information System (INIS)

    Du Daping; Wang Bin; Su Ruheng

    2004-01-01

    We have studied scalar perturbations as well as fermion perturbations in pure de Sitter spacetimes. For scalar perturbations we have shown that well-defined quasinormal modes in d-dimensions can exist provided that the mass of scalar field m>(d-1/2l). The quasinormal modes of fermion perturbations in three and four dimensional cases have also been investigated. We found that different from other dimensional cases, in the three dimensional pure de Sitter spacetime there is no quasinormal mode for the s-wave. This interesting difference caused by the spacial dimensions is true for both scalar and fermion perturbations

  20. Minimal covariant observables identifying all pure states

    Energy Technology Data Exchange (ETDEWEB)

    Carmeli, Claudio, E-mail: claudio.carmeli@gmail.com [D.I.M.E., Università di Genova, Via Cadorna 2, I-17100 Savona (Italy); I.N.F.N., Sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku (Finland); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); I.N.F.N., Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy)

    2013-09-02

    It has been recently shown by Heinosaari, Mazzarella and Wolf (2013) [1] that an observable that identifies all pure states of a d-dimensional quantum system has minimally 4d−4 outcomes or slightly less (the exact number depending on d). However, no simple construction of this type of minimal observable is known. We investigate covariant observables that identify all pure states and have minimal number of outcomes. It is shown that the existence of this kind of observables depends on the dimension of the Hilbert space.

  1. Critical opalescence in the pure Coulomb system

    Science.gov (United States)

    Bobrov, V. B.; Trigger, S. A.

    2011-04-01

    Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.

  2. Effectiveness of Motorcycle speed controlled by speed hump

    Directory of Open Access Journals (Sweden)

    Pornsiri Urapa

    2014-09-01

    Full Text Available Speed humps are one of the traffic calming measures widely accepted to control vehicle speed in the local road. Humps standards from the western countries are designed mainly for the passenger car. This study, therefore, aims to reveal the effectiveness of speed hump to control the motorcycle speed. This study observes the free-flow speed of the riders at the total of 20 speed bumps and humps. They are 0.3-14.8 meter in width and 5-18 centimeter in height. The results reveal that the 85th percentile speeds reduce 15-65 percent when crossing the speed bumps and speed humps. Besides, this study develops the speed model to predict the motorcycle mean speed and 85th percentile speed. It is found that speed humps follow the ITE standard can control motorcycle crossing speeds to be 25-30 Kph which are suitable to travel on the local road.

  3. Comparison of hydrogen storage properties of pure Mg and milled ...

    Indian Academy of Sciences (India)

    Administrator

    increase the hydriding and dehydriding rates, pure Mg was ground under hydrogen atmosphere (reactive .... Hydrogen storage properties of pure Mg and milled pure Mg. 833. Figure 3. ... elongated and flat shapes via collisions with the steel.

  4. RELAXATION OF WARPED DISKS: THE CASE OF PURE HYDRODYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Sorathia, Kareem A.; Krolik, Julian H. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Hawley, John F. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

    2013-05-10

    Orbiting disks may exhibit bends due to a misalignment between the angular momentum of the inner and outer regions of the disk. We begin a systematic simulational inquiry into the physics of warped disks with the simplest case: the relaxation of an unforced warp under pure fluid dynamics, i.e., with no internal stresses other than Reynolds stress. We focus on the nonlinear regime in which the bend rate is large compared to the disk aspect ratio. When warps are nonlinear, strong radial pressure gradients drive transonic radial motions along the disk's top and bottom surfaces that efficiently mix angular momentum. The resulting nonlinear decay rate of the warp increases with the warp rate and the warp width, but, at least in the parameter regime studied here, is independent of the sound speed. The characteristic magnitude of the associated angular momentum fluxes likewise increases with both the local warp rate and the radial range over which the warp extends; it also increases with increasing sound speed, but more slowly than linearly. The angular momentum fluxes respond to the warp rate after a delay that scales with the square root of the time for sound waves to cross the radial extent of the warp. These behaviors are at variance with a number of the assumptions commonly used in analytic models to describe linear warp dynamics.

  5. Color Spectrum Properties of Pure and Non-Pure LATEX in Discriminating Rubber Clone Series

    International Nuclear Information System (INIS)

    Noor Aishah Khairuzzaman; Hadzli Hashim; Nina Korlina Madzhi; Noor Ezan Abdullah; Faridatul Aima Ismail; Ahmad Faiz Sampian; Azhana Fatnin Che Will

    2015-01-01

    A study of color spectrum properties for pure and non-pure latex in discriminating rubber clone series has been presented in this paper. There were five types of clones from the same series being used as samples in this study named RRIM2002, RRIM2007, RRIM2008, RRIM2014, and RRIM3001. The main objective is to identify the significant color spectrum (RGB) from pure and non-pure latex that can discriminate rubber clone series. The significant information of color spectrum properties for pure and non-pure latex is determined by using spectrometer and Statistical Package for the Social Science (SPSS). Visible light spectrum (VIS) is used as a radiation light of the spectrometer to emit light to the surface of the latex sample. By using SPSS software, the further numerical analysis of color spectrum properties is being conducted. As the conclusion, blue color spectrum for non-pure is able to discriminate for all rubber clone series whereas only certain color spectrum can differentiate several clone series for pure latex. (author)

  6. On the Possibility of Laser Cladding for 304 Stainless Steel using Commercially Pure Titanium

    OpenAIRE

    Hashem F. El-Labban; Essam R.I. Mahmoud

    2014-01-01

    This work is an attempt to study the possibility of cladding the 304 stainless steel with commercially pure titanium powder using YAG fiber laser. The treatments were carried out at powers of 2800, 2400 and 2000 W and travelling speeds of 4 and 8 mm/s. In the titanium side, acicular α' martensite structure was produced. At low travelling speed (4 mm/s), coarse intermetallic phases (FeTi and Fe2Ti) were formed, and decohesion were resulted at the interface between the cladding layer and the su...

  7. Investigations in Pure Mathematics: A Constructivist Perspective.

    Science.gov (United States)

    Hirst, Keith; Shiu, Christine

    1995-01-01

    Discusses an investigative, constructivist approach in the context of undergraduate mathematics, with particular reference to pure mathematics, general aims and objectives, assessment strategies, and problems of supervision that affect tutors and lecturers using this approach. Gives students' views on their experiences in this mode of working. (19…

  8. Eco-Cities: Possible or Purely Utopian?

    Science.gov (United States)

    2009-12-01

    00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Eco-Cities: Possible or Purely Utopian? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...2005, Disney modified their building plans for Hong Kong Disneyland by shifting the angle of the front gate by twelve degrees in order to abide by

  9. 76 FR 69284 - Pure Magnesium From China

    Science.gov (United States)

    2011-11-08

    ... China Determination On the basis of the record \\1\\ developed in the subject five-year review, the United... China would be likely to lead to continuation or recurrence of material injury to an industry in the...), entitled Pure Magnesium from China: Investigation No. 731-TA-696 (Third Review). Issued: November 2, 2011...

  10. Is word recognition crowded in pure alexia?

    DEFF Research Database (Denmark)

    Sand, Katrine; Habekost, Thomas; Petersen, Anders

    2017-01-01

    Pure alexia is a selective deficit in reading, which arises following damage to the left ventral occipito-temporal cortex. Crowding, the inability to recognise objects in a clutter, has recently been hypothesised to be the underlying deficit of apperceptive visual agnosia1. Crowding normally occurs...

  11. Perceptions of the Pure Pallet Program

    National Research Council Canada - National Science Library

    Dye, Michael T

    2006-01-01

    .... Recommendations center on educating personnel on the importance of suboptimization avoidance and making the warfighter the most important customer. This research also serves as a formal source of information from which to form conclusions and make judgments on how well Air Force personnel are implementing the pure pallet program.

  12. Purely Magnetic Silent Universes do not Exist

    Science.gov (United States)

    Vu, K. T.; Carminati, J.

    2008-09-01

    We present a new Maple package called STeM (Symbolic Tetrad Manipulation). Using STeM, we outline, using a formalism which is a hybrid of the NP and Orthonormal ones, the proof of the nonexistence of purely magnetic silent universes.

  13. Bayero Journal of Pure and Applied Sciences

    African Journals Online (AJOL)

    The Journal's scope is wide in that it reported findings in the areas of pure and ... Physics, Medical Sciences and Zoology form part of the contents of the Journal. Scientists in the academia, research institutes and industries are therefore ...

  14. Critical current of pure SNS junctions

    International Nuclear Information System (INIS)

    Golub, A.A.; Bezzub, O.P.

    1982-01-01

    Boundary conditions at the superconductor-normal metal interface are determined, taking into account the differences in the effective masses and the density of states of the metals constituting the transition and assumed to be pure. The potential barrier of the interface is chosen to be zero. The critical current of the junction is calculated [ru

  15. Traffic speed management

    Directory of Open Access Journals (Sweden)

    Subotić Jovana Lj.

    2014-01-01

    Full Text Available Speed, and vehicles themselves, affect the level of service and road safety, quality of life, noise from traffic, the environment, health, air pollution, emission of carbon dioxide, global warming, the economy and consumption of non-renewable energy such as oil. Therefore, the speed management of the traffic of multiple significance and that should be primarily to provide effective and economical conditions of the modern and preventive protection of human life as the greatest treasure and then the material resources. The way to accomplish this is by using various (different measures such as: appropriate planning and projecting roads and streets, speed control, the legislation, enforcement, campaigns, education, advanced technologies (ITS.

  16. High-Speed Photography

    International Nuclear Information System (INIS)

    Paisley, D.L.; Schelev, M.Y.

    1998-01-01

    The applications of high-speed photography to a diverse set of subjects including inertial confinement fusion, laser surgical procedures, communications, automotive airbags, lightning etc. are briefly discussed. (AIP) copyright 1998 Society of Photo-Optical Instrumentation Engineers

  17. Wind_Speeds_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included wind speeds for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  18. High speed data acquisition

    International Nuclear Information System (INIS)

    Cooper, P.S.

    1997-07-01

    A general introduction to high speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E78 1) high statistics charmed baryon production and decay experiment now taking data at Fermilab

  19. High speed heterostructure devices

    CERN Document Server

    Beer, Albert C; Willardson, R K; Kiehl, Richard A; Sollner, T C L Gerhard

    1994-01-01

    Volume 41 includes an in-depth review of the most important, high-speed switches made with heterojunction technology. This volume is aimed at the graduate student or working researcher who needs a broad overview andan introduction to current literature. Key Features * The first complete review of InP-based HFETs and complementary HFETs, which promise very low power and high speed * Offers a complete, three-chapter review of resonant tunneling * Provides an emphasis on circuits as well as devices.

  20. Optical and structural characterization of the pure and doped BaY{sub 2}F{sub 8} with rare earths for application in radiation detectors and scintillators; Caracterizacao optica e estrutural do BaY{sub 2}F{sub 8} puro e dopado com terras raras visando aplicacao em detectores de radiacao e cintiladores

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Ana Carolina Santana de

    2008-07-01

    In this work Barium Yttrium Fluoride (BaY{sub 2}F{sub 8} -BaYF) doped with different concentrations of ions Tb{sup 3+}, Er{sup 3+}, Tm{sup 3+} e Nd{sup 3+} were characterized, aiming the application in radiation detection devices that use the scintillating properties. Two types of samples were produced in the CLA-IPEN-SP, polycrystalline samples, obtained via solid state reaction of BaF{sub 2} and YF{sub 3} under HF atmosphere, and single crystals, obtained via the zone melting method also in a HF atmosphere. The samples were characterized using the following experimental techniques: X-ray powder diffraction, Radioluminescence (RL), Optical Absorption and Dispersive X-ray Absorption Spectroscopy (DXAS). The X-ray diffraction pattern showed the presence of the phase BaY{sub 2}F{sub 8} and a small amount of the phase Ba{sub 4}Y{sub 3}F{sub 17} in the polycrystalline pure and Tb{sup 3+}doped samples. The other samples showed only the desired BaY{sub 2}F{sub 8} phase. The radioluminescence measurements of the doped BaYF, when irradiated with X-rays, showed emission peaks in energies that are characteristics of the 4f-4f transitions of rare earths. The RL of the samples with 2 mol por cent and 3 mold of Tb{sup 3+}showed quite intense peaks with a maximum emission peak at 545 nm. The Tm{sup 3+}doped BYF showed that the scintillation efficiency is not directly proportional to the doping level, and the highest RL emission were obtained for the polycrystalline samples doped with 1 mol por cent, showing a maximum peak intensity at 456 nm (the blue region of the visible spectrum). All samples showed a phosphorescent decay time of the order of seconds. Single crystals of BaYF doped with 2 mol por cent of Er{sup 3+}, in addition to one of the highest phosphorescence time, presents a quite strong Rl in the green region of the spectra. The radiation damage was evaluated by the optical absorption techniques and the results showed that the formation of the absorption bands can be

  1. Production and thermal stability of pure and Cr3+ -doped hydroxyapatite

    International Nuclear Information System (INIS)

    De Araujo, T S; De Souza, S O; De Sousa, E M B; Araujo, M S

    2010-01-01

    Hydroxyapatite (HAP) have been used as starting material for biomedical applications. The pure and Cr 3+ -doped hydroxyapatite were prepared by chemical precipitation reactions at 100, 500 e 800 0 C in order to investigate the thermal stability of these materials. The characterization of the thermal behavior of this phosphate, especially on the structural changes with heating, is very important for production of sunscreens The powders were characterized using chemical analysis: X-ray diffraction (XRD) and thermal analysis. The present study was successful in the preparation of pure hydroxyapatite and chromium substituted hydroxyapatites with good thermal stability and nanoparticles formation.

  2. Compound effects of inhaling pure oxygen and lifting height on ear baric function in a hypobaric chamber

    Directory of Open Access Journals (Sweden)

    Dong-qing WEN

    2017-02-01

    Full Text Available Objective To compare the ear baric function between 4000m altitude chamber test with inhaling air and 6900m altitude chamber test with inhaling pure oxygen. Methods Eleven healthy male volunteers attended two tests as two groups by self-comparison. As the air group the volunteers inhaled air at 4000m, while as the pure oxygen group they inhaled pure oxygen at 6900m altitude, and the time interval between the two tests was more than two weeks. During the test, the volunteers breathed air or pure oxygen at random for 1h, and then were exposed at a speed of 20m/s to the target altitude for 5min. Hereafter they were sent back to the ground at the same speed. The changes of subjective symptoms, degree of tympanic congestion, acoustic immitance index and pure-tone auditory threshold were recorded before and after the test. The acoustic impedance index and pure-tone threshold were statistically analyzed. Results Four volunteers (4 ears in air group and 7 volunteers (7 ears in pure oxygen group reported ear pain in altitude chamber exposures, respectively. The pain-triggering altitude was higher in the pure oxygen group. Immediately after tests, there were 3 (3 ears and 5 volunteers (5 ears with Ⅲ degree congestion of the tympanic membrane in the two groups respectively. Four volunteers (6 ears developed gradually aggravated hemorrhages after altitude exposure. And the tympanic membrane congestion difference between groups was statistically significant at 3 and 24h after tests (P<0.01. The type A tympanogram appeared in 11 (15 ears and 11 (14 ears volunteers respectively immediately after tests. The increase of static compliance value was significantly greater in pure oxygen group than in air group immediately after tests (P<0.05, the decrease of middle ear pressure was more significant in pure oxygen group than in air group at 3 and 24h after tests (P<0.05. Both the two altitude exposure tests resulted in eustachian tube dysfunction. At 3 and

  3. Square-root measurement for pure states

    International Nuclear Information System (INIS)

    Huang Siendong

    2005-01-01

    Square-root measurement is a very useful suboptimal measurement in many applications. It was shown that the square-root measurement minimizes the squared error for pure states. In this paper, the least squared error problem is reformulated and a new proof is provided. It is found that the least squared error depends only on the average density operator of the input states. The properties of the least squared error are then discussed, and it is shown that if the input pure states are uniformly distributed, the average probability of error has an upper bound depending on the least squared error, the rank of the average density operator, and the number of the input states. The aforementioned properties help explain why the square-root measurement can be effective in decoding processes

  4. Black hole attractors and pure spinors

    International Nuclear Information System (INIS)

    Hsu, Jonathan P.; Maloney, Alexander; Tomasiello, Alessandro

    2006-01-01

    We construct black hole attractor solutions for a wide class of N = 2 compactifications. The analysis is carried out in ten dimensions and makes crucial use of pure spinor techniques. This formalism can accommodate non-Kaehler manifolds as well as compactifications with flux, in addition to the usual Calabi-Yau case. At the attractor point, the charges fix the moduli according to Σf k = Im(CΦ), where Φ is a pure spinor of odd (even) chirality in IIB (A). For IIB on a Calabi-Yau, Φ = Ω and the equation reduces to the usual one. Methods in generalized complex geometry can be used to study solutions to the attractor equation

  5. International Standardization of Pure Beta Emitters

    International Nuclear Information System (INIS)

    Los Arcos, Jose Maria; Rodriguez, Leonor

    2006-01-01

    The paper describes the traditional methods of standardization of Pure Beta Emitters, their principal characteristics, advantage and drawbacks. It does comparisons between two metrological LSC methods: Triple to double coincidence ratio (TDCR) method and the CIEMAT/NIST method and presents the result obtained with several Key Comparisons serving as practical test of both methods. Both of them represent the siferrit of methods of standardization of pure (and mixed decay) radionuclides. ESIR WG of CCRI(II) is to implement a reference exchange system for the permanent equivalence of β, α and electron capture nuclides, similar to traditional SIR gamma. ESIR project is currently testing a new XAN scintillator and operational tests of the whole system at BIPM are expected by the end of 2006 (test restricted to ESIR NMI members)

  6. Scattering equations, supergravity integrands, and pure spinors

    Energy Technology Data Exchange (ETDEWEB)

    Adamo, Tim; Casali, Eduardo [Department of Applied Mathematics & Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2015-05-25

    The tree-level S-matrix of type II supergravity can be computed in scattering equation form by correlators in a worldsheet theory analogous to a chiral, infinite tension limit of the pure spinor formalism. By defining a non-minimal version of this theory, we give a prescription for computing correlators on higher genus worldsheets which manifest space-time supersymmetry. These correlators are conjectured to provide the loop integrands of supergravity scattering amplitudes, supported on the scattering equations. We give non-trivial evidence in support of this conjecture at genus one and two with four external states. Throughout, we find a close correspondence with the pure spinor formalism of superstring theory, particularly regarding regulators and zero-mode counting.

  7. Heat engine driven by purely quantum information.

    Science.gov (United States)

    Park, Jung Jun; Kim, Kang-Hwan; Sagawa, Takahiro; Kim, Sang Wook

    2013-12-06

    The key question of this Letter is whether work can be extracted from a heat engine by using purely quantum mechanical information. If the answer is yes, what is its mathematical formula? First, by using a bipartite memory we show that the work extractable from a heat engine is bounded not only by the free energy change and the sum of the entropy change of an individual memory but also by the change of quantum mutual information contained inside the memory. We then find that the engine can be driven by purely quantum information, expressed as the so-called quantum discord, forming a part of the quantum mutual information. To confirm it, as a physical example we present the Szilard engine containing a diatomic molecule with a semipermeable wall.

  8. Black Hole Attractors and Pure Spinors

    International Nuclear Information System (INIS)

    Hsu, Jonathan P.; Maloney, Alexander; Tomasiello, Alessandro

    2006-01-01

    We construct black hole attractor solutions for a wide class of N = 2 compactifications. The analysis is carried out in ten dimensions and makes crucial use of pure spinor techniques. This formalism can accommodate non-Kaehler manifolds as well as compactifications with flux, in addition to the usual Calabi-Yau case. At the attractor point, the charges fix the moduli according to Σf k = Im(CΦ), where Φ is a pure spinor of odd (even) chirality in IIB (A). For IIB on a Calabi-Yau, Φ = (Omega) and the equation reduces to the usual one. Methods in generalized complex geometry can be used to study solutions to the attractor equation

  9. Scattering equations, supergravity integrands, and pure spinors

    International Nuclear Information System (INIS)

    Adamo, Tim; Casali, Eduardo

    2015-01-01

    The tree-level S-matrix of type II supergravity can be computed in scattering equation form by correlators in a worldsheet theory analogous to a chiral, infinite tension limit of the pure spinor formalism. By defining a non-minimal version of this theory, we give a prescription for computing correlators on higher genus worldsheets which manifest space-time supersymmetry. These correlators are conjectured to provide the loop integrands of supergravity scattering amplitudes, supported on the scattering equations. We give non-trivial evidence in support of this conjecture at genus one and two with four external states. Throughout, we find a close correspondence with the pure spinor formalism of superstring theory, particularly regarding regulators and zero-mode counting.

  10. Critical opalescence in the pure Coulomb system

    Energy Technology Data Exchange (ETDEWEB)

    Bobrov, V.B., E-mail: vic5907@mail.r [Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaia St., 13, Bd. 2. Moscow 125412 (Russian Federation); Trigger, S.A., E-mail: satron@mail.r [Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaia St., 13, Bd. 2. Moscow 125412 (Russian Federation); Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, D-12489 Berlin (Germany)

    2011-04-18

    Highlights: The review of the critical opalescence problem is presented. Light scattering in a two-component electron-nuclear system is studied. The exact relations between the structure factors and compressibility are found. The obtained relations are valid for strong interaction for the Coulomb systems. The experimental verification of these relations is possible for various elements. - Abstract: Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.

  11. Critical opalescence in the pure Coulomb system

    International Nuclear Information System (INIS)

    Bobrov, V.B.; Trigger, S.A.

    2011-01-01

    Highlights: → The review of the critical opalescence problem is presented. → Light scattering in a two-component electron-nuclear system is studied. → The exact relations between the structure factors and compressibility are found. → The obtained relations are valid for strong interaction for the Coulomb systems. → The experimental verification of these relations is possible for various elements. - Abstract: Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.

  12. Compact objects in pure Lovelock theory

    Science.gov (United States)

    Dadhich, Naresh; Hansraj, Sudan; Chilambwe, Brian

    For static fluid interiors of compact objects in pure Lovelock gravity (involving only one Nth order term in the equation), we establish similarity in solutions for the critical odd and even d = 2N + 1, 2N + 2 dimensions. It turns out that in critical odd d = 2N + 1 dimensions, there cannot exist any bound distribution with a finite radius, while in critical even d = 2N + 2 dimensions, all solutions have similar behavior. For exhibition of similarity, we would compare star solutions for N = 1, 2 in d = 4 Einstein and d = 6 in Gauss-Bonnet theory, respectively. We also obtain the pure Lovelock analogue of the Finch-Skea model.

  13. Analysis of pure and malachite green doped polysulfone sample using FT-IR technique

    Science.gov (United States)

    Nayak, Rashmi J.; Khare, P. K.; Nayak, J. G.

    2018-05-01

    The sample of pure and malachite green doped Polysulfone in the form of foil was prepared by isothermal immersion technique. For the preparation of pure sample 4 gm of Polysulfone was dissolved in 50 ml of Dimethyl farmamide (DMF) solvent, while for the preparation of doped sample 10 mg, 50 mg and 100 mg Malachite Green was mixed with 4 gm of Polysulfone respectively. For the study of structural characterization of these pure and doped sample, Fourier Transform Infra-Red Spectroscopy (FT-IR) technique was used. This study shows that the intensity of transmittance decreases as the ratio of doping increases in pure polysulfone. The reduction in intensity of transmittance is clearly apparent in the present case more over the bands were broader which indicates towards charge transfer interaction between the donar and acceptor molecule.

  14. Pure subrings of the rings Zχ

    International Nuclear Information System (INIS)

    Tsarev, Andrei V

    2009-01-01

    Pure subrings of finite rank in the Z-adic completion of the ring of integers and in its homomorphic images are considered. Certain properties of these rings are studied (existence of an identity element, decomposability into a direct sum of essentially indecomposable ideals, condition for embeddability into a csp-ring, etc.). Additive groups of these rings and conditions under which these rings are subrings of algebraic number fields are described. Bibliography: 12 titles.

  15. Production of Purely Gravitational Dark Matter

    OpenAIRE

    Ema, Yohei; Nakayama, Kazunori; Tang, Yong

    2018-01-01

    In the purely gravitational dark matter scenario, the dark matter particle does not have any interaction except for gravitational one. We study the gravitational particle production of dark matter particle in such a minimal setup and show that correct amount of dark matter can be produced depending on the inflation model and the dark matter mass. In particular, we carefully evaluate the particle production rate from the transition epoch to the inflaton oscillation epoch in a realistic inflati...

  16. Notes on the ambitwistor pure spinor string

    Czech Academy of Sciences Publication Activity Database

    Lipinski Jusinskas, Renann

    2016-01-01

    Roč. 2016, č. 5 (2016), s. 1-12, č. článku 116. ISSN 1029-8479 R&D Projects: GA ČR GBP201/12/G028 Institutional support: RVO:68378271 Keywords : ambitwistor string * pure spinor formalism Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 6.063, year: 2016

  17. About the elaboration of pure uranium dicarbide

    International Nuclear Information System (INIS)

    Besson, J.; Blum, P.; Guinet, Ph.; Spitz, J.

    1963-01-01

    In order to develop methods for the elaboration of as pure as possible uranium dicarbide, the authors report the study of different elaboration processes based on the reaction between uranium and carbon, or between uranium and hydrocarbon, or between uranium oxide and carbon. They finally choose a method which comprises an arc-induced fusion of a mixture of uranium dioxide and carbon. The fusion process is described. The influence of thermal treatments is discussed as well as the graphite electrode carburization

  18. Unitary evolution between pure and mixed states

    International Nuclear Information System (INIS)

    Reznik, B.

    1996-01-01

    We propose an extended quantum mechanical formalism that is based on a wave operator d, which is related to the ordinary density matrix via ρ=dd degree . This formalism allows a (generalized) unitary evolution between pure and mixed states. It also preserves much of the connection between symmetries and conservation laws. The new formalism is illustrated for the case of a two-level system. copyright 1996 The American Physical Society

  19. Sasakian manifolds with purely transversal Bach tensor

    Science.gov (United States)

    Ghosh, Amalendu; Sharma, Ramesh

    2017-10-01

    We show that a (2n + 1)-dimensional Sasakian manifold (M, g) with a purely transversal Bach tensor has constant scalar curvature ≥2 n (2 n +1 ) , equality holding if and only if (M, g) is Einstein. For dimension 3, M is locally isometric to the unit sphere S3. For dimension 5, if in addition (M, g) is complete, then it has positive Ricci curvature and is compact with finite fundamental group π1(M).

  20. Preparation of pure anhydrous rare earth chlorides

    International Nuclear Information System (INIS)

    Bel'kova, N.L.; Slastenova, N.M.; Batyaev, I.M.; Solov'ev, M.A.

    1979-01-01

    A method has been suggested for obtaining extra-pure anhydrous REE chlorides by chloridizing corresponding oxalates by chlorine in a fluid bed, the chloridizing agents being diluted by an inert gas in a ratio of 2-to-1. The method is applicable to the manufacture of quality chlorides not only of light, but also of heavy REE. Neodymium chloride has an excited life of tau=30 μs, this evidencing the absence of the damping impurities

  1. Preparation of very pure active carbon

    International Nuclear Information System (INIS)

    Sloot, H.A. van der; Hoede, D.; Zonderhuis, J.; Meijer, C.

    1980-02-01

    The preparation of very pure active carbon is described. Starting from polyvinylidene chloride active carbon is prepared by carbonization in a nitrogen atmosphere, grinding, sieving and activation of the powder fraction with CO 2 at 950 0 to approximately 50% burn-off. The concentrations of trace and major elements are reduced to the ppb and ppm level, respectively. In the present set-up 100 g of carbon grains and approximately 50 g of active carbon powder can be produced weekly

  2. Graphical calculus for Gaussian pure states

    International Nuclear Information System (INIS)

    Menicucci, Nicolas C.; Flammia, Steven T.; Loock, Peter van

    2011-01-01

    We provide a unified graphical calculus for all Gaussian pure states, including graph transformation rules for all local and semilocal Gaussian unitary operations, as well as local quadrature measurements. We then use this graphical calculus to analyze continuous-variable (CV) cluster states, the essential resource for one-way quantum computing with CV systems. Current graphical approaches to CV cluster states are only valid in the unphysical limit of infinite squeezing, and the associated graph transformation rules only apply when the initial and final states are of this form. Our formalism applies to all Gaussian pure states and subsumes these rules in a natural way. In addition, the term 'CV graph state' currently has several inequivalent definitions in use. Using this formalism we provide a single unifying definition that encompasses all of them. We provide many examples of how the formalism may be used in the context of CV cluster states: defining the 'closest' CV cluster state to a given Gaussian pure state and quantifying the error in the approximation due to finite squeezing; analyzing the optimality of certain methods of generating CV cluster states; drawing connections between this graphical formalism and bosonic Hamiltonians with Gaussian ground states, including those useful for CV one-way quantum computing; and deriving a graphical measure of bipartite entanglement for certain classes of CV cluster states. We mention other possible applications of this formalism and conclude with a brief note on fault tolerance in CV one-way quantum computing.

  3. Electron Acoustic Waves in Pure Ion Plasmas

    Science.gov (United States)

    Anderegg, F.; Driscoll, C. F.; Dubin, D. H. E.; O'Neil, T. M.

    2009-11-01

    Electron Acoustic Waves (EAW) are the low frequency branch of electrostatic plasma waves. These waves exist in neutralized plasmas, pure electron plasmas and in pure ion plasmasfootnotetextF. Anderegg et al., PRL 102, 095001 (2009) and PoP 16, 055705 (2009). (where the name is deceptive). Here, we observe standing mθ= 0 mz= 1 EAWs in a pure ion plasma column. At small amplitude, the EAWs have a phase velocity vph ˜1.4 v, and the frequencies are in close agreement with theory. At moderate amplitudes, waves can be excited over a broad range of frequencies, with observed phase velocities in the range of 1.4 v vph diagnostic shows that particles slower than vph oscillate in phase with the wave, while particles moving faster than vph oscillate 180^o out of phase with the wave. From a fluid perspective, this gives an unusual negative dynamical compressibility. That is, the wave pressure oscillations are 180^o out of phase from the density oscillations, almost fully canceling the electrostatic restoring force, giving the low and malleable frequency.

  4. Everyone Deserves a Speeding Ticket.

    Science.gov (United States)

    Burris, Harold

    1993-01-01

    Presents a first day physics activity having students determine the fine for a speeding ticket if the speeds considered include the earth's rotation and revolution speed, and the movement through the galaxy. (MDH)

  5. Speed of disentanglement in multiqubit systems under a depolarizing channel

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fu-Lin, E-mail: flzhang@tju.edu.cn; Jiang, Yue; Liang, Mai-Lin, E-mail: mailinliang@yahoo.com.cn

    2013-06-15

    We investigate the speed of disentanglement in the multiqubit systems under the local depolarizing channel, in which each qubit is independently coupled to the environment. We focus on the bipartition entanglement between one qubit and the remaining qubits constituting the system, which is measured by the negativity. For the two-qubit system, the speed for the pure state completely depends on its entanglement. The upper and lower bounds of the speed for arbitrary two-qubit states, and the necessary conditions for a state achieving them, are obtained. For the three-qubit system, we study the speed for pure states, whose entanglement properties can be completely described by five local-unitary-transformation invariants. An analytical expression of the relation between the speed and the invariants is derived. The speed is enhanced by the three-tangle which is the entanglement among the three qubits, but reduced by the two-qubit correlations outside the concurrence. The decay of the negativity can be restrained by the other two negativity with the coequal sense. The unbalance between two qubits can reduce the speed of disentanglement of the remaining qubit in the system, and even can retrieve the entanglement partially. For the k-qubit systems in an arbitrary superposition of Greenberger–Horne–Zeilinger state and W state, the speed depends almost entirely on the amount of the negativity when k increases to five or six. An alternative quantitative definition for the robustness of entanglement is presented based on the speed of disentanglement, with comparison to the widely studied robustness measured by the critical amount of noise parameter where the entanglement vanishes. In the limit of large number of particles, the alternative robustness of the Greenberger–Horne–Zeilinger-type states is inversely proportional to k, and the one of the W states approaches 1/√(k)

  6. PERSONALITY AND SPEEDING

    Directory of Open Access Journals (Sweden)

    Richard TAY

    2003-01-01

    Full Text Available While there has been extensive research on the effect of sensation seeking on risky driving, relatively little research has been conducted on Type-A personality. The motivations for speeding are likely to be different for each group and these differences have important implications for the design, implementation and expected efficacy of road safety countermeasures. This paper examines the influence of sensation seeking and Type-A behavior pattern on speeding behaviour. A sample of 139 staff and students in an Australian university were surveyed in July 2001 to gather information on their gender, age, personality and self-reported speeding behaviour. The data were analysed using correlations and analysis of variance procedures. Finally, some implications for road safety are discussed.

  7. Speed-calming measures and their Effect on driving speed

    DEFF Research Database (Denmark)

    Agerholm, Niels; Knudsen, Daniel; Variyeswaran, Kajan

    2017-01-01

    Highlights •Speed humps and chicanes are widespread speed-calming measures. •Humps and chicanes have virtually the same reducing effect on mean speed. •Chicanes reduce speed variation less than humps and might therefore be a less safe measure....

  8. Purely elastic scattering theories and their ultraviolet limits

    International Nuclear Information System (INIS)

    Klassen, T.R.; Chicago Univ., IL; Melzer, E.

    1990-01-01

    We use the thermodynamic Bethe ansatz to find the finite-size corrections to the ground-state energy in an arbitrary (1+1)-dimensional purely elastic scattering theory. The leading finite-size effects are characterized by tilde c=c-12d 0 , where c and d 0 are the central charge and the lowest scaling dimension, respectively, of the (possibly nonunitary) CFT describing the ultraviolet limit of the massive scattering theory. After presenting the purely elastic S-matrix theories that emerged in recent discussions of perturbed CFTs, we calculate their finite-size scaling coefficient tilde c. Our results show that the UV limits of the 'minimal' S-matrix theories are the unperturbed CFTs in question. On the other hand, the S-matrices which have been suggested to describe affine Toda field theories, differing from the minimal S-matrices by coupling-dependent factors, are seen to have free bosonic CFTs as their UV limits. We also discuss some interesting properties of tilde c. In particular, we suggest that tilde c is a measure of the number of degrees of freedom of an arbitrary two-dimensional CFT. (orig.)

  9. Economic impacts associated with pure taxable capacity changes

    International Nuclear Information System (INIS)

    Bjornstad, D.J.

    1978-01-01

    An attempt is made to broaden the purview of fiscal impact analysis to include impacts on the local private sector that may stem from local public sector changes. More specifically, attention is focused on the limiting case, in which new private sector development yields positive changes in fiscal capacity, but does not increase public service demands or interact with the local private sector. This phenomenon is termed a ''pure'' change in fiscal capacity, or, stated differently, pure tax revenue importation. Interest in this issue stems from an analysis of the local impacts of constructing and operating nuclear power stations. Nuclear power stations, like other electrical generating facilities, are characterized by large capital-labor ratios, implying that the impact of siting would be to increase local taxable capacity, via the property tax base, to a greater extent than local private sector activity, via new hirings. Moreover, a small labor force implies a modest change in the demand for local public services, and facilities of this nature by themselves demand few, if any, public services. A nuclear power station, however, may be distinguished from other electrical generating facilities through siting regulations that require locating in a low population density area, a fact which ensures the influence on the community will be substantial. The question of how and to what degree feedback effects from local public to local private sector may take place is described

  10. Relativistic stars with purely toroidal magnetic fields

    International Nuclear Information System (INIS)

    Kiuchi, Kenta; Yoshida, Shijun

    2008-01-01

    We investigate the effects of the purely toroidal magnetic field on the equilibrium structures of the relativistic stars. The basic equations for obtaining equilibrium solutions of relativistic rotating stars containing purely toroidal magnetic fields are derived for the first time. To solve these basic equations numerically, we extend the Cook-Shapiro-Teukolsky scheme for calculating relativistic rotating stars containing no magnetic field to incorporate the effects of the purely toroidal magnetic fields. By using the numerical scheme, we then calculate a large number of the equilibrium configurations for a particular distribution of the magnetic field in order to explore the equilibrium properties. We also construct the equilibrium sequences of the constant baryon mass and/or the constant magnetic flux, which model the evolution of an isolated neutron star as it loses angular momentum via the gravitational waves. Important properties of the equilibrium configurations of the magnetized stars obtained in this study are summarized as follows: (1) For the nonrotating stars, the matter distribution of the stars is prolately distorted due to the toroidal magnetic fields. (2) For the rapidly rotating stars, the shape of the stellar surface becomes oblate because of the centrifugal force. But, the matter distribution deep inside the star is sufficiently prolate for the mean matter distribution of the star to be prolate. (3) The stronger toroidal magnetic fields lead to the mass shedding of the stars at the lower angular velocity. (4) For some equilibrium sequences of the constant baryon mass and magnetic flux, the stars can spin up as they lose angular momentum.

  11. chemf: A purely functional chemistry toolkit.

    Science.gov (United States)

    Höck, Stefan; Riedl, Rainer

    2012-12-20

    Although programming in a type-safe and referentially transparent style offers several advantages over working with mutable data structures and side effects, this style of programming has not seen much use in chemistry-related software. Since functional programming languages were designed with referential transparency in mind, these languages offer a lot of support when writing immutable data structures and side-effects free code. We therefore started implementing our own toolkit based on the above programming paradigms in a modern, versatile programming language. We present our initial results with functional programming in chemistry by first describing an immutable data structure for molecular graphs together with a couple of simple algorithms to calculate basic molecular properties before writing a complete SMILES parser in accordance with the OpenSMILES specification. Along the way we show how to deal with input validation, error handling, bulk operations, and parallelization in a purely functional way. At the end we also analyze and improve our algorithms and data structures in terms of performance and compare it to existing toolkits both object-oriented and purely functional. All code was written in Scala, a modern multi-paradigm programming language with a strong support for functional programming and a highly sophisticated type system. We have successfully made the first important steps towards a purely functional chemistry toolkit. The data structures and algorithms presented in this article perform well while at the same time they can be safely used in parallelized applications, such as computer aided drug design experiments, without further adjustments. This stands in contrast to existing object-oriented toolkits where thread safety of data structures and algorithms is a deliberate design decision that can be hard to implement. Finally, the level of type-safety achieved by Scala highly increased the reliability of our code as well as the productivity of

  12. Modeling of speed distribution for mixed bicycle traffic flow

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2015-11-01

    Full Text Available Speed is a fundamental measure of traffic performance for highway systems. There were lots of results for the speed characteristics of motorized vehicles. In this article, we studied the speed distribution for mixed bicycle traffic which was ignored in the past. Field speed data were collected from Hangzhou, China, under different survey sites, traffic conditions, and percentages of electric bicycle. The statistics results of field data show that the total mean speed of electric bicycles is 17.09 km/h, 3.63 km/h faster and 27.0% higher than that of regular bicycles. Normal, log-normal, gamma, and Weibull distribution models were used for testing speed data. The results of goodness-of-fit hypothesis tests imply that the log-normal and Weibull model can fit the field data very well. Then, the relationships between mean speed and electric bicycle proportions were proposed using linear regression models, and the mean speed for purely electric bicycles or regular bicycles can be obtained. The findings of this article will provide effective help for the safety and traffic management of mixed bicycle traffic.

  13. A Mathematical Model of Marine Diesel Engine Speed Control System

    Science.gov (United States)

    Sinha, Rajendra Prasad; Balaji, Rajoo

    2018-02-01

    Diesel engine is inherently an unstable machine and requires a reliable control system to regulate its speed for safe and efficient operation. Also, the diesel engine may operate at fixed or variable speeds depending upon user's needs and accordingly the speed control system should have essential features to fulfil these requirements. This paper proposes a mathematical model of a marine diesel engine speed control system with droop governing function. The mathematical model includes static and dynamic characteristics of the control loop components. Model of static characteristic of the rotating fly weights speed sensing element provides an insight into the speed droop features of the speed controller. Because of big size and large time delay, the turbo charged diesel engine is represented as a first order system or sometimes even simplified to a pure integrator with constant gain which is considered acceptable in control literature. The proposed model is mathematically less complex and quick to use for preliminary analysis of the diesel engine speed controller performance.

  14. Synthesis of highly phase pure BSCCO superconductors

    Science.gov (United States)

    Dorris, S.E.; Poeppel, R.B.; Prorok, B.C.; Lanagan, M.T.; Maroni, V.A.

    1995-11-21

    An article and method of manufacture (Bi, Pb)-Sr-Ca-Cu-O superconductor are disclosed. The superconductor is manufactured by preparing a first powdered mixture of bismuth oxide, lead oxide, strontium carbonate, calcium carbonate and copper oxide. A second powdered mixture is then prepared of strontium carbonate, calcium carbonate and copper oxide. The mixtures are calcined separately with the two mixtures then combined. The resulting combined mixture is then subjected to a powder in tube deformation and thermal processing to produce a substantially phase pure (Bi, Pb)-Sr-Ca-Cu-O superconductor. 5 figs.

  15. Initial singularity and pure geometric field theories

    Science.gov (United States)

    Wanas, M. I.; Kamal, Mona M.; Dabash, Tahia F.

    2018-01-01

    In the present article we use a modified version of the geodesic equation, together with a modified version of the Raychaudhuri equation, to study initial singularities. These modified equations are used to account for the effect of the spin-torsion interaction on the existence of initial singularities in cosmological models. Such models are the results of solutions of the field equations of a class of field theories termed pure geometric. The geometric structure used in this study is an absolute parallelism structure satisfying the cosmological principle. It is shown that the existence of initial singularities is subject to some mathematical (geometric) conditions. The scheme suggested for this study can be easily generalized.

  16. Purely cubic action for string field theory

    Science.gov (United States)

    Horowitz, G. T.; Lykken, J.; Rohm, R.; Strominger, A.

    1986-01-01

    It is shown that Witten's (1986) open-bosonic-string field-theory action and a closed-string analog can be written as a purely cubic interaction term. The conventional form of the action arises by expansion around particular solutions of the classical equations of motion. The explicit background dependence of the conventional action via the Becchi-Rouet-Stora-Tyutin operator is eliminated in the cubic formulation. A closed-form expression is found for the full nonlinear gauge-transformation law.

  17. Pure phase decoherence in a ring geometry

    International Nuclear Information System (INIS)

    Zhu, Z.; Aharony, A.; Entin-Wohlman, O.; Stamp, P. C. E.

    2010-01-01

    We study the dynamics of pure phase decoherence for a particle hopping around an N-site ring, coupled both to a spin bath and to an Aharonov-Bohm flux which threads the ring. Analytic results are found for the dynamics of the influence functional and of the reduced density matrix of the particle, both for initial single wave-packet states, and for states split initially into two separate wave packets moving at different velocities. We also give results for the dynamics of the current as a function of time.

  18. Radial and axial compression of pure electron

    International Nuclear Information System (INIS)

    Park, Y.; Soga, Y.; Mihara, Y.; Takeda, M.; Kamada, K.

    2013-01-01

    Experimental studies are carried out on compression of the density distribution of a pure electron plasma confined in a Malmberg-Penning Trap in Kanazawa University. More than six times increase of the on-axis density is observed under application of an external rotating electric field that couples to low-order Trivelpiece-Gould modes. Axial compression of the density distribution with the axial length of a factor of two is achieved by controlling the confining potential at both ends of the plasma. Substantial increase of the axial kinetic energy is observed during the axial compression. (author)

  19. Pure and Public, Popular and personal

    DEFF Research Database (Denmark)

    Eriksson, Birgit

    2013-01-01

    In the article I reexamine the traditional aesthetical and political critiques of popular culture and reevaluate the social and communicative potential of bestselling cultural artifacts such as highly popular television series. First, I sketch the alleged aesthetic and social problems of popular...... and the exclusions of the public sphere. I argue that the ideals of a pure aesthetic and a public sphere neglect issues that are crucial to the type of commonality at stake in popular cultural artifacts: personal issues, social conflicts, and what is pleasurable to the senses or has to do with emotions. Third, I...

  20. Synthesis of pure Portland cement phases

    DEFF Research Database (Denmark)

    Wesselsky, Andreas; Jensen, Ole Mejlhede

    2009-01-01

    Pure phases commonly found in Portland cement clinkers are often used to test cement hydration behaviour in simplified experimental conditions. The synthesis of these phases is covered in this paper, starting with a description of phase relations and possible polymorphs of the four main phases...... in Portland cement, i.e. tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium alumino ferrite. Details of the The process of solid state synthesis are is described in general including practical advice on equipment and techniques. Finally In addition, some exemplary mix compositions...

  1. Preparation of a pure molecular quantum gas.

    Science.gov (United States)

    Herbig, Jens; Kraemer, Tobias; Mark, Michael; Weber, Tino; Chin, Cheng; Nägerl, Hanns-Christoph; Grimm, Rudolf

    2003-09-12

    An ultracold molecular quantum gas is created by application of a magnetic field sweep across a Feshbach resonance to a Bose-Einstein condensate of cesium atoms. The ability to separate the molecules from the atoms permits direct imaging of the pure molecular sample. Magnetic levitation enables study of the dynamics of the ensemble on extended time scales. We measured ultralow expansion energies in the range of a few nanokelvin for a sample of 3000 molecules. Our observations are consistent with the presence of a macroscopic molecular matter wave.

  2. Heat engine driven by purely quantum information

    OpenAIRE

    Park, Jung Jun; Kim, Kang-Hwan; Sagawa, Takahiro; Kim, Sang Wook

    2013-01-01

    The key question of this paper is whether work can be extracted from a heat engine by using purely quantum mechanical information. If the answer is yes, what is its mathematical formula? First, by using a bipartite memory we show that the work extractable from a heat engine is bounded not only by the free energy change and the sum of the entropy change of an individual memory but also by the change of quantum mutual information contained inside the memory. We then find that the engine can be ...

  3. Quantum correlations support probabilistic pure state cloning

    Energy Technology Data Exchange (ETDEWEB)

    Roa, Luis, E-mail: lroa@udec.cl [Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Alid-Vaccarezza, M.; Jara-Figueroa, C. [Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Klimov, A.B. [Departamento de Física, Universidad de Guadalajara, Avenida Revolución 1500, 44420 Guadalajara, Jalisco (Mexico)

    2014-02-01

    The probabilistic scheme for making two copies of two nonorthogonal pure states requires two auxiliary systems, one for copying and one for attempting to project onto the suitable subspace. The process is performed by means of a unitary-reduction scheme which allows having a success probability of cloning different from zero. The scheme becomes optimal when the probability of success is maximized. In this case, a bipartite state remains as a free degree which does not affect the probability. We find bipartite states for which the unitarity does not introduce entanglement, but does introduce quantum discord between some involved subsystems.

  4. Dynamical structure of pure Lovelock gravity

    Science.gov (United States)

    Dadhich, Naresh; Durka, Remigiusz; Merino, Nelson; Miskovic, Olivera

    2016-03-01

    We study the dynamical structure of pure Lovelock gravity in spacetime dimensions higher than four using the Hamiltonian formalism. The action consists of a cosmological constant and a single higher-order polynomial in the Riemann tensor. Similarly to the Einstein-Hilbert action, it possesses a unique constant curvature vacuum and charged black hole solutions. We analyze physical degrees of freedom and local symmetries in this theory. In contrast to the Einstein-Hilbert case, the number of degrees of freedom depends on the background and can vary from zero to the maximal value carried by the Lovelock theory.

  5. Intelligent Speed Assistance (ISA).

    NARCIS (Netherlands)

    2015-01-01

    Intelligent Speed Assistance (ISA) has been a promising type of advanced driver support system for some decades. From a technical point of view, large scale ISA implementation is possible in the short term. The different types of ISA are expected to have different effects on behaviour and traffic

  6. Speed mathematics simplified

    CERN Document Server

    Stoddard, Edward

    1994-01-01

    Entertaining, easy-to-follow suggestions for developing greater speed and accuracy in doing mathematical calculations. Surefire methods for multiplying without carrying, dividing with half the pencil work of long division, plus advice on how to add and subtract rapidly, master fractions, work quickly with decimals, handle percentages, and much more.

  7. High speed metal removal

    Science.gov (United States)

    Pugh, R. F.; Pohl, R. F.

    1982-10-01

    Four types of steel (AISI 1340, 4140, 4340, and HF-1) which are commonly used in large caliber projectile manufacture were machined at different hardness ranges representing the as-forged and the heat treated condition with various ceramic tools using ceramic coated tungsten carbide as a reference. Results show that machining speeds can be increased significantly using present available tooling.

  8. Variable speed generators

    CERN Document Server

    Boldea, Ion

    2005-01-01

    With the deregulation of electrical energy production and distribution, says Boldea (Polytechnical Institute, Timisoara, Romania) producers are looking for ways to tailor their electricity for different markets. Variable-speed electric generators are serving that purpose, up to the 400 megavolt ampere unit size, in Japan since 1996 and Germany sinc

  9. Quantum speed limits for Bell-diagonal states

    International Nuclear Information System (INIS)

    Han Wei; Jiang Ke-Xia; Zhang Ying-Jie; Xia Yun-Jie

    2015-01-01

    The lower bounds of the evolution time between two distinguishable states of a system, defined as quantum speed limit time, can characterize the maximal speed of quantum computers and communication channels. We study the quantum speed limit time between the composite quantum states and their target states in the presence of nondissipative decoherence. For the initial states with maximally mixed marginals, we obtain the exact expressions of the quantum speed limit time which mainly depend on the parameters of the initial states and the decoherence channels. Furthermore, by calculating the quantum speed limit time for the time-dependent states started from a class of initial states, we discover that the quantum speed limit time gradually decreases in time, and the decay rate of the quantum speed limit time would show a sudden change at a certain critical time. Interestingly, at the same critical time, the composite system dynamics would exhibit a sudden transition from classical decoherence to quantum decoherence. (paper)

  10. Testing of newly developed functional surfaces under pure sliding conditions

    DEFF Research Database (Denmark)

    Godi, Alessandro; Mohaghegh, Kamran; Grønbæk, J.

    2013-01-01

    the surfaces in an industrial context. In this paper, a number of experimental tests were performed using a novel test rig, called axial sliding test, simulating the contact of surfaces under pure sliding conditions. The aim of the experiments is to evaluate the frictional behavior of a new typology...... of textured surfaces, the so-called multifunctional surfaces, characterized by a plateau area able to bear loads and a deterministic pattern of lubricant pockets. Six surface typologies, namely three multifunctional and three machined using classical processes, were chosen to slide against a mirror....... The results comparison showed clearly how employing multifunctional surfaces can reduce friction forces up to 50 % at high normal loads compared to regularly ground or turned surfaces. Friction coefficients approximately equal to 0.12 were found for classically machined surfaces, whereas the values were 0...

  11. Kinetics of thermal grooving during low temperature recrystallization of pure aluminum

    DEFF Research Database (Denmark)

    Zhang, Yubin; Godfrey, Andy; Juul Jensen, Dorte

    2013-01-01

    The migration of a recrystallization boundary in pure aluminum was followed during in situ annealing in a scanning electron microscope. The microstructure was characterized using the electron channeling contrast technique, and a typical stop-go grain boundary motion was observed during annealing...

  12. Pure spinor partition function and the massive superstring spectrum

    International Nuclear Information System (INIS)

    Aisaka, Yuri; Arroyo, E. Aldo; Berkovits, Nathan; Nekrasov, Nikita

    2008-01-01

    We explicitly compute up to the fifth mass-level the partition function of ten-dimensional pure spinor worldsheet variables including the spin dependence. After adding the contribution from the (x μ , θ α , p α ) matter variables, we reproduce the massive superstring spectrum. Even though pure spinor variables are bosonic, the pure spinor partition function contains fermionic states which first appear at the second mass-level. These fermionic states come from functions which are not globally defined in pure spinor space, and are related to the b ghost in the pure spinor formalism. This result clarifies the proper definition of the Hilbert space for pure spinor variables.

  13. On the importance of PURE - Public Understanding of Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Broman, Lars; Kandpal, Tara C.

    2013-09-15

    Public understanding of science (PUS) is a central concept among science communicators. Public understanding of renewable energy (PURE) is proposed as an important sub-concept of PUS. The aim of this paper is to interest and invite renewable energy scientists to join a PURE research project. Four separate important questions for a PURE research project can be identified: (A) Is PURE important? (B) Which issues of PURE are the most important ones, according to renewable energy scientists? (C) What understanding of renewable energy has the general public today, worldwide? (D) How to achieve PURE?.

  14. High-power pure blue laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, M.; Ohizumi, Y.; Hoshina, Y.; Tanaka, T.; Yabuki, Y.; Goto, S.; Ikeda, M. [Development Center, Sony Shiroishi Semiconductor Inc., Miyagi (Japan); Funato, K. [Materials Laboratories, Sony Corporation, Kanagawa (Japan); Tomiya, S. [Materials Analysis Laboratory, Sony Corporation, Kanagawa (Japan)

    2007-06-15

    We successfully developed high-power and long-lived pure blue laser diodes (LDs) having an emission wavelength of 440-450 nm. The pure-blue LDs were grown by metalorganic chemical vapor deposition (MOCVD) on GaN substrates. The dislocation density was successfully reduced to {proportional_to}10{sup 6} cm{sup -2} by optimizing the MOCVD growth conditions and the active layer structure. The vertical layer structure was designed to have an absorption loss of 4.9 cm{sup -1} and an internal quantum efficiency of 91%. We also reduced the operating current density to 6 kA/cm{sup 2} under 750 mW continuous-wave operation at 35 C by optimizing the stripe width to 12 {mu}m and the cavity length to 2000 {mu}m. The half lifetimes in constant current mode are estimated to be longer than 10000 h. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Purely temporal figure-ground segregation.

    Science.gov (United States)

    Kandil, F I; Fahle, M

    2001-05-01

    Visual figure-ground segregation is achieved by exploiting differences in features such as luminance, colour, motion or presentation time between a figure and its surround. Here we determine the shortest delay times required for figure-ground segregation based on purely temporal features. Previous studies usually employed stimulus onset asynchronies between figure- and ground-containing possible artefacts based on apparent motion cues or on luminance differences. Our stimuli systematically avoid these artefacts by constantly showing 20 x 20 'colons' that flip by 90 degrees around their midpoints at constant time intervals. Colons constituting the background flip in-phase whereas those constituting the target flip with a phase delay. We tested the impact of frequency modulation and phase reduction on target detection. Younger subjects performed well above chance even at temporal delays as short as 13 ms, whilst older subjects required up to three times longer delays in some conditions. Figure-ground segregation can rely on purely temporal delays down to around 10 ms even in the absence of luminance and motion artefacts, indicating a temporal precision of cortical information processing almost an order of magnitude lower than the one required for some models of feature binding in the visual cortex [e.g. Singer, W. (1999), Curr. Opin. Neurobiol., 9, 189-194]. Hence, in our experiment, observers are unable to use temporal stimulus features with the precision required for these models.

  16. MRI of autosomal dominant pure spastic paraplegia

    International Nuclear Information System (INIS)

    Krabbe, K.; Fallentin, E.; Herning, M.; Nielsen, J.E.; Fenger, K.

    1997-01-01

    We examined 16 patients with autosomal dominant pure spastic paraplegia (HSP) and 15 normal controls matched for age and sex using MRI of the brain and spinal cord. Images were assessed qualitatively by two independent radiologists, blinded to the clinical diagnosis. Areas of the brain and corpus callosum on one midsagittal slice and the area of the brain on one axial slice were measured and a ''corpus-callosum index'' expressing the size of the corpus callosum relative to that of the brain was calculated. Cross-sectional areas and anteroposterior and transverse diameters of the spinal cord at the levels of C 2, C 5, T 3, T 6, T 9 and T 11 were measured. No significant differences between patients and controls were found on qualitative evaluation of the images. The patients had a significantly smaller corpus callosum and ''corpus-callosum index'' than controls. This finding, not reported previously, might indicate that the disease process in pure HSP is not confined to the spinal cord. The anteroposterior diameters of the spinal cord at T 3 and T 9 were significantly smaller in patients than in controls. This might correspond to the degeneration of the pyramidal tracts and the dorsal columns described at neuropathological examination. (orig.). With 1 fig., 3 tabs

  17. MRI of autosomal dominant pure spastic paraplegia

    Energy Technology Data Exchange (ETDEWEB)

    Krabbe, K.; Fallentin, E.; Herning, M. [Danish Research Center of Magnetic Resonance, Hvidovre Hospital, Kettegaard alle 30, DK-2650 Hvidovre (Denmark); Nielsen, J.E.; Fenger, K. [Institute of Medical Biochemistry and Genetics, Laboratory of Medical Genetics, Section of Neurogenetics, University of Copenhagen (Denmark)

    1997-10-01

    We examined 16 patients with autosomal dominant pure spastic paraplegia (HSP) and 15 normal controls matched for age and sex using MRI of the brain and spinal cord. Images were assessed qualitatively by two independent radiologists, blinded to the clinical diagnosis. Areas of the brain and corpus callosum on one midsagittal slice and the area of the brain on one axial slice were measured and a ``corpus-callosum index`` expressing the size of the corpus callosum relative to that of the brain was calculated. Cross-sectional areas and anteroposterior and transverse diameters of the spinal cord at the levels of C 2, C 5, T 3, T 6, T 9 and T 11 were measured. No significant differences between patients and controls were found on qualitative evaluation of the images. The patients had a significantly smaller corpus callosum and ``corpus-callosum index`` than controls. This finding, not reported previously, might indicate that the disease process in pure HSP is not confined to the spinal cord. The anteroposterior diameters of the spinal cord at T 3 and T 9 were significantly smaller in patients than in controls. This might correspond to the degeneration of the pyramidal tracts and the dorsal columns described at neuropathological examination. (orig.). With 1 fig., 3 tabs.

  18. Nanoporous Au: an unsupported pure gold catalyst?

    Energy Technology Data Exchange (ETDEWEB)

    Wittstock, A; Neumann, B; Schaefer, A; Dumbuya, K; Kuebel, C; Biener, M; Zielasek, V; Steinrueck, H; Gottfried, M; Biener, J; Hamza, A; B?umer, M

    2008-09-04

    The unique properties of gold especially in low temperature CO oxidation have been ascribed to a combination of various effects. In particular, particle sizes below a few nm and specific particle-support interactions have been shown to play important roles. On the contrary, recent reports revealed that monolithic nanoporous gold (npAu) prepared by leaching a less noble metal, such as Ag, out of the corresponding alloy can also exhibit remarkably high catalytic activity for CO oxidation, even though no support is present. Therefore, it was claimed to be a pure and unsupported gold catalyst. We investigated npAu with respect to its morphology, surface composition and catalytic properties. In particular, we studied the reaction kinetics for low temperature CO oxidation in detail taking mass transport limitation due to the porous structure of the material into account. Our results reveal that Ag, even if removed almost completely from the bulk, segregates to the surface resulting in surface concentrations of up to 10 at%. Our data suggest that this Ag plays a significant role in activation of molecular oxygen. Therefore, npAu should be considered as a bimetallic catalyst rather than a pure Au catalyst.

  19. Tribological Properties of Surface-Textured and Plasma-Nitrided Pure Titanium Under Oil Lubrication Condition

    Science.gov (United States)

    Zhang, Baosen; Dong, Qiangsheng; Ba, Zhixin; Wang, Zhangzhong; Shi, Hancheng; Xue, Yanting

    2018-01-01

    Plasma nitriding was conducted as post-treatment for surface texture on pure titanium to obtain a continuous nitriding layer. Supersonic fine particles bombarding (SFPB) was carried out to prepare surface texture. The surface morphologies and chemical composition were analyzed using scanning electron microscope and energy disperse spectroscopy. The microstructures of modified layers were characterized by transmission electron microscope. The tribological properties of surface-textured and duplex-treated pure titanium under oil lubrication condition were systematically investigated in the ball-on-plate reciprocating mode. The effects of applied load and sliding velocity on the tribological behavior were analyzed. The results show that after duplex treatments, the grains size in modified layer becomes slightly larger, and hardness is obviously improved. Wear resistance of duplex-treated pure titanium is significantly improved referenced to untreated and surface-textured pure titanium, which is 3.22 times as much as untreated pure titanium and 2.15 times of that for surface-textured pure titanium, respectively.

  20. Variable sound speed in interacting dark energy models

    Science.gov (United States)

    Linton, Mark S.; Pourtsidou, Alkistis; Crittenden, Robert; Maartens, Roy

    2018-04-01

    We consider a self-consistent and physical approach to interacting dark energy models described by a Lagrangian, and identify a new class of models with variable dark energy sound speed. We show that if the interaction between dark energy in the form of quintessence and cold dark matter is purely momentum exchange this generally leads to a dark energy sound speed that deviates from unity. Choosing a specific sub-case, we study its phenomenology by investigating the effects of the interaction on the cosmic microwave background and linear matter power spectrum. We also perform a global fitting of cosmological parameters using CMB data, and compare our findings to ΛCDM.

  1. Probes for narcotic receptor mediated phenomena 22. Pt.1: Synthesis and characterization of optically pure [{sup 3}H](+)-4-[({alpha}R)-{alpha}-((2S,5R)-4-propyl-2,5-dimethyl-1-pi perazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide, [{sup 3}H]SNC 121, a novel high affinity and selective ligand for delta opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, S.N.; Bertha, C.M.; Rice, K.C. [National Inst. of Diabetes and Digestive and Kidney Diseases, Medicinal Chemistry Lab., Bethesda, MD (United States); Gutkind, J.S. [National Inst. of Dental Research, Bethesda, MD (United States); Heng Xu; Partilla, J.S.; Rothman, R.B. [National Inst. on Drug Abuse, Clinical Psychopharmacology Section, Baltimore, MD (United States)

    1996-09-01

    The synthesis of unlabelled and labelled SNC 121, a selective nonpeptide ligand for the delta opioid receptor is reported. [{sup 3}H]SNC 121 of specific activity of 26.8 Ci/mmol, was synthesized by catalytic tritiation of the optically pure precursor SNC 80. (author).

  2. Probes for narcotic receptor mediated phenomena 22. Pt.1: Synthesis and characterization of optically pure [3H](+)-4-[(αR)-α-((2S,5R)-4-propyl-2,5-dimethyl-1-pi perazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide, [3H]SNC 121, a novel high affinity and selective ligand for delta opioid receptors

    International Nuclear Information System (INIS)

    Calderon, S.N.; Bertha, C.M.; Rice, K.C.; Gutkind, J.S.; Heng Xu; Partilla, J.S.; Rothman, R.B.

    1996-01-01

    The synthesis of unlabelled and labelled SNC 121, a selective nonpeptide ligand for the delta opioid receptor is reported. [ 3 H]SNC 121 of specific activity of 26.8 Ci/mmol, was synthesized by catalytic tritiation of the optically pure precursor SNC 80. (author)

  3. Improving speed behaviour : the potential of in-car speed assistance and speed limit credibility.

    NARCIS (Netherlands)

    Nes, C.N. van Houtenbos, M. & Schagen, I.N.L.G. van

    2009-01-01

    Speeding is still a common practice on many roads and it contributes to a significant number of crashes. Two new approaches to solve speeding issues are focused on: intelligent speed assistance systems (ISA) and speed limit credibility. Research has indicated that ISA is promising with respect to

  4. Chapter 12. Pure Tap Water Hydraulic Systems and Applications

    DEFF Research Database (Denmark)

    Conrad, Finn; Adelstorp, Anders

    1997-01-01

    Presentation of developed a modern pure tap water hydraulic components (Nessie), systems and industrial applications.......Presentation of developed a modern pure tap water hydraulic components (Nessie), systems and industrial applications....

  5. Production of tomato puree: an alternative to conservation of locally ...

    African Journals Online (AJOL)

    Mo

    suggest a mean of conservation of the surplus of production by processing tomato into puree. The most produced local ... processing into puree on industrial scale. The main .... functions contributing to the reaction of non-enzymatic browning ...

  6. Archives: Bayero Journal of Pure and Applied Sciences

    African Journals Online (AJOL)

    Items 1 - 20 of 20 ... Archives: Bayero Journal of Pure and Applied Sciences. Journal Home > Archives: Bayero Journal of Pure and Applied Sciences. Log in or Register to get access to full text downloads.

  7. Nigeria Journal of Pure and Applied Physics: Journal Sponsorship

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics: Journal Sponsorship. Journal Home > About the Journal > Nigeria Journal of Pure and Applied Physics: Journal Sponsorship. Log in or Register to get access to full text downloads.

  8. Archives: Nigeria Journal of Pure and Applied Physics

    African Journals Online (AJOL)

    Items 1 - 6 of 6 ... Archives: Nigeria Journal of Pure and Applied Physics. Journal Home > Archives: Nigeria Journal of Pure and Applied Physics. Log in or Register to get access to full text downloads.

  9. Nigeria Journal of Pure and Applied Physics: About this journal

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics: About this journal. Journal Home > Nigeria Journal of Pure and Applied Physics: About this journal. Log in or Register to get access to full text downloads.

  10. Nigeria Journal of Pure and Applied Physics: Site Map

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics: Site Map. Journal Home > About the Journal > Nigeria Journal of Pure and Applied Physics: Site Map. Log in or Register to get access to full text downloads.

  11. High speed network sampling

    OpenAIRE

    Rindalsholt, Ole Arild

    2005-01-01

    Master i nettverks- og systemadministrasjon Classical Sampling methods play an important role in the current practice of Internet measurement. With today’s high speed networks, routers cannot manage to generate complete Netflow data for every packet. They have to perform restricted sampling. This thesis summarizes some of the most important sampling schemes and their applications before diving into an analysis on the effect of sampling Netflow records.

  12. Option Panels in Pure-Jump Settings

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Fusari, Nicola; Todorov, Viktor

    We develop parametric inference procedures for large panels of noisy option data in the setting where the underlying process is of pure-jump type, i.e., evolve only through a sequence of jumps. The panel consists of options written on the underlying asset with a (different) set of strikes...... specification for the risk-neutral asset return dynamics, the option prices are nonlinear functions of a time-invariant parameter vector and a time-varying latent state vector (or factors). Furthermore, no-arbitrage restrictions impose a direct link between some of the quantities that may be identified from...... the return and option data. These include the so-called jump activity index as well as the time-varying jump intensity. We propose penalized least squares estimation in which we minimize L_2 distance between observed and model-implied options and further penalize for the deviation of model-implied quantities...

  13. High temperature internal friction in pure aluminium

    International Nuclear Information System (INIS)

    Aboagye, J.K.; Payida, D.S.

    1982-05-01

    The temperature dependence of internal friction of nearly pure aluminium (99.99% aluminium) has been carefully measured as a function of annealing temperature and hence grain size. The results indicate that, provided the frequency and annealing temperature are held constant, the internal friction increases with temperature until some maximum value is attained and then begins to go down as the temperature is further increased. It is also noted that the internal friction decreases with annealing temperature and that annealing time has the same effect as annealing temperature. It is also noted that the internal friction peak is shifted towards higher temperatures as annealing temperature is increased. It is surmised that the grain size or the total grain boundary volume determines the height of the internal friction curve and that the order-disorder transitions at the grain boundaries induced by both entropy and energy gradients give rise to internal friction peaks in polycrystals. (author)

  14. Black holes in pure Lovelock gravities

    International Nuclear Information System (INIS)

    Cai Ronggen; Ohta, Nobuyoshi

    2006-01-01

    Lovelock gravity is a fascinating extension of general relativity, whose action consists of dimensionally extended Euler densities. Compared to other higher order derivative gravity theories, Lovelock gravity is attractive since it has a lot of remarkable features such as the fact that there are no more than second order derivatives with respect to the metric in its equations of motion, and that the theory is free of ghosts. Recently, in the study of black strings and black branes in Lovelock gravity, a special class of Lovelock gravity is considered, which is named pure Lovelock gravity, where only one Euler density term exists. In this paper we study black hole solutions in the special class of Lovelock gravity and associated thermodynamic properties. Some interesting features are found, which are quite different from the corresponding ones in general relativity

  15. Axisymmetric Eigenmodes of Spheroidal Pure Electron Plasmas

    Science.gov (United States)

    Kawai, Yosuke; Saitoh, Haruhiko; Yoshida, Zensho; Kiwamoto, Yasuhito

    2010-11-01

    The axisymmetric electrostatic eigenmodes of spheroidal pure electron plasmas have been studied experimentally. It is confirmed that the observed spheroidal plasma attains a theoretically expected equilibrium density distribution, with the exception of a low-density halo distribution surrounding the plasma. When the eigenmode frequency observed for the plasma is compared with the frequency predicted by the dispersion relation derived under ideal conditions wherein the temperature is zero and the boundary is located at an infinite distance from the plasma, it is observed that the absolute value of the observed frequency is systematically higher than the theoretical prediction. Experimental examinations and numerical calculations indicate that the upward shift of the eigenmode frequency cannot be accounted for solely by the finite temperature effect, but is significantly affected by image charges induced on the conducting boundary and the resulting distortion of the density profile from the theoretical expectation.

  16. MRI of autosomal dominant pure spastic paraplegia

    DEFF Research Database (Denmark)

    Krabbe, K.; Nielsen, J.E.; Fallentin, E.

    1997-01-01

    We examined 16 patients with autosomal dominant pure spastic paraplegia (HSP) and 15 normal controls matched for age and sex using MRI of the brain and spinal cord. Images were assessed qualitatively by two independent radiologists, blinded to the clinical diagnosis. Areas of the brain and corpus...... callosum on one midsagittal slice and the area of the brain on one axial slice were measured and a "corpus-callosum index" expressing the size of the corpus callosum relative to that of the brain was calculated. Cross-sectional areas and anteroposterior and transverse diameters of the spinal cord...... at the levels of C 2, C 5, T 3, T 6, T 9 and T 11 were measured. No significant differences between patients and controls were found on qualitative evaluation of the images. The patients had a significantly smaller corpus callosum and "corpus-callosum index" than controls. This finding, not reported previously...

  17. Catalytic transformations for bipartite pure states

    International Nuclear Information System (INIS)

    Turgut, S

    2007-01-01

    Entanglement catalysis is a phenomenon that usually enhances the conversion probability in the transformation of entangled states by the temporary involvement of another entangled state (so-called catalyst), where after the process is completed the catalyst is returned to the same state. For some pairs of bipartite pure entangled states, catalysis enables a transformation with unit probability of success, in which case the respective Schmidt coefficients of the states are said to satisfy the trumping relation, a mathematical relation which is an extension of the majorization relation. This paper provides all necessary and sufficient conditions for the trumping and two other associated relations. Using these conditions, the least upper bound of conversion probabilities using catalysis is also obtained. Moreover, best conversion ratios achievable with catalysis are found for transformations involving many copies of states

  18. Selective Laser Melting of Pure Copper

    Science.gov (United States)

    Ikeshoji, Toshi-Taka; Nakamura, Kazuya; Yonehara, Makiko; Imai, Ken; Kyogoku, Hideki

    2018-03-01

    Appropriate building parameters for selective laser melting of 99.9% pure copper powder were investigated at relatively high laser power of 800 W for hatch pitch in the range from 0.025 mm to 0.12 mm. The highest relative density of the built material was 99.6%, obtained at hatch pitch of 0.10 mm. Building conditions were also studied using transient heat analysis in finite element modeling of the liquidation and solidification of the powder layer. The estimated melt pool length and width were comparable to values obtained by observations using a thermoviewer. The trend for the melt pool width versus the hatch pitch agreed with experimental values.

  19. Momentum of the Pure Radiation Field

    Directory of Open Access Journals (Sweden)

    Lehnert B.

    2007-01-01

    Full Text Available The local momentum equation of the pure radiation field is considered in terms of an earlier elaborated and revised electromagnetic theory. In this equation the contribution from the volume force is found to vanish in rectangular geometry, and to become nonzero but negligible in cylindrical geometry. Consequently the radiated momentum is due to the Poynting vector only, as in conventional electrodynamics. It results in physically relevant properties of a photon model having an angular momentum (spin. The Poynting vector concept is further compared to the quantized momentum concept for a free particle, as represented by a spatial gradient operator acting on the wave function. However, this latter otherwise successful concept leads to difficulties in the physical interpretation of known and expected photon properties such as the spin, the negligible loss of transverse momentum across a bounding surface, and the Lorentz invariance.

  20. Tractable Quantification of Entanglement for Multipartite Pure States

    International Nuclear Information System (INIS)

    Nian-Quan, Jiang; Yu-Jian, Wang; Yi-Zhuang, Zheng; Gen-Chang, Cai

    2008-01-01

    We present kth-order entanglement measure and global kth-order entanglement measure for multipartite pure states, and extend Bennett's measure of partial entropy for bipartite pure states to a multipartite case. These measures are computable and can effectively classify and quantify the entanglement of multipartite pure states. (general)

  1. Balancing High-Speed Rotors at Low Speed

    Science.gov (United States)

    Giordano, J.; Zorzi, E.

    1986-01-01

    Flexible balancing reduces vibrations at operating speeds. Highspeed rotors in turbomachines dynamically balanced at fraction of operating rotor speed. New method takes into account rotor flexible rather than rigid.

  2. Speed, speed variation and crash relationships for urban arterials.

    Science.gov (United States)

    Wang, Xuesong; Zhou, Qingya; Quddus, Mohammed; Fan, Tianxiang; Fang, Shou'en

    2018-04-01

    Speed and speed variation are closely associated with traffic safety. There is, however, a dearth of research on this subject for the case of urban arterials in general, and in the context of developing nations. In downtown Shanghai, the traffic conditions in each direction are very different by time of day, and speed characteristics during peak hours are also greatly different from those during off-peak hours. Considering that traffic demand changes with time and in different directions, arterials in this study were divided into one-way segments by the direction of flow, and time of day was differentiated and controlled for. In terms of data collection, traditional fixed-based methods have been widely used in previous studies, but they fail to capture the spatio-temporal distributions of speed along a road. A new approach is introduced to estimate speed variation by integrating spatio-temporal speed fluctuation of a single vehicle with speed differences between vehicles using taxi-based high frequency GPS data. With this approach, this paper aims to comprehensively establish a relationship between mean speed, speed variation and traffic crashes for the purpose of formulating effective speed management measures, specifically using an urban dataset. From a total of 234 one-way road segments from eight arterials in Shanghai, mean speed, speed variation, geometric design features, traffic volume, and crash data were collected. Because the safety effects of mean speed and speed variation may vary at different segment lengths, arterials with similar signal spacing density were grouped together. To account for potential correlations among these segments, a hierarchical Poisson log-normal model with random effects was developed. Results show that a 1% increase in mean speed on urban arterials was associated with a 0.7% increase in total crashes, and larger speed variation was also associated with increased crash frequency. Copyright © 2018 Elsevier Ltd. All rights

  3. The role of visual processing speed in reading speed development.

    Science.gov (United States)

    Lobier, Muriel; Dubois, Matthieu; Valdois, Sylviane

    2013-01-01

    A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span), predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.

  4. Monitoring speed before and during a speed publicity campaign.

    NARCIS (Netherlands)

    Schagen, I.N.L.G. van Commandeur, J.J.F. Goldenbeld, C. & Stipdonk, H.

    2016-01-01

    Driving speeds were monitored during a period of 16 weeks encompassing different stages of an anti-speeding campaign in the Netherlands. This campaign targeted speed limit violations in built-up areas. The observation periods differed in terms of intensity and media used for the campaign. Small

  5. The role of visual processing speed in reading speed development.

    Directory of Open Access Journals (Sweden)

    Muriel Lobier

    Full Text Available A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span, predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.

  6. Crystal growth kinetics in undercooled melts of pure Ge, Si and Ge-Si alloys

    Science.gov (United States)

    Herlach, Dieter M.; Simons, Daniel; Pichon, Pierre-Yves

    2018-01-01

    We report on measurements of crystal growth dynamics in semiconducting pure Ge and pure Si melts and in Ge100-xSix (x = 25, 50, 75) alloy melts as a function of undercooling. Electromagnetic levitation techniques are applied to undercool the samples in a containerless way. The growth velocity is measured by the utilization of a high-speed camera technique over an extended range of undercooling. Solidified samples are examined with respect to their microstructure by scanning electron microscopic investigations. We analyse the experimental results of crystal growth kinetics as a function of undercooling within the sharp interface theory developed by Peter Galenko. Transitions of the atomic attachment kinetics are found at large undercoolings, from faceted growth to dendrite growth. This article is part of the theme issue `From atomistic interfaces to dendritic patterns'.

  7. Experimental study of negative corona discharge in pure carbon dioxide and its mixtures with oxygen

    International Nuclear Information System (INIS)

    Mikoviny, T; Kocan, M; Matejcik, S; Mason, N J; Skalny, J D

    2004-01-01

    The products of a negative corona discharge in both pure CO 2 and mixtures of CO 2 + O 2 have been studied using a coaxial cylindrical electrode geometry with particular emphasis on the production of ozone. The discharge current in pure CO 2 was found to be highly sensitive to the presence of trace concentrations of molecular oxygen and to changes in the flow speed through the discharge. The effect of dissociative electron attachment to ozone on the discharge current was studied by measurements of ozone and CO production. The ozone concentration increases monotonically with increasing content of oxygen in the mixture with carbon dioxide, whereas the CO concentration exhibits a flat maximum for oxygen concentrations of around 4%. A simple kinetic model of the dominant chemical processes is described and compared with the experimental results

  8. Isotopically pure single crystal epitaxial diamond films and their preparation

    International Nuclear Information System (INIS)

    Banholzer, W.F.; Anthony, T.R.; Williams, D.M.

    1992-01-01

    The present invention is directed to the production of single crystal diamond consisting of isotopically pure carbon-12 or carbon-13. In the present invention, isotopically pure single crystal diamond is grown on a single crystal substrate directly from isotopically pure carbon-12 or carbon-13. One method for forming isotopically pure single crystal diamond comprises the steps of placing in a reaction chamber a single substrate heated to an elevated diamond forming temperature. Another method for forming isotopically pure single crystal diamond comprises diffusing isotopically pure carbon-12 or carbon-13 through a metallic catalyst under high pressure to a region containing a single crystal substrate to form an isotopically pure single crystal diamond layer on said single crystal substrate

  9. Mechanical Behavior of Commercially Pure Titanium Weldments at Lower Temperatures

    Science.gov (United States)

    Gupta, R. K.; Anil Kumar, V.; Xavier, X. Roshan

    2018-05-01

    Commercially pure titanium is used for low-temperature applications due to good toughness attributed to single-phase microstructure (α). Electron beam welding (EBW) and gas tungsten arc welding (GTAW) processes have been used for welding two grades of commercially pure titanium (Grade 2 and Grade 4). Martensitic microstructure is found to be finer in the case of EBW joint as compared to GTAW joint due to faster rate of cooling in the former process. Weldments have been characterized to study the mechanical behavior at ambient (298 K) and cryogenic temperatures (20 and 77 K). Strength of weldments increases with the decrease in temperature, which is found to be more prominent in case of Grade 4 titanium as compared to Grade 2. Weld efficiency of Grade 4 is found to be higher at all the temperatures (ambient, 77 and 20 K). However, ultimate tensile strength/yield strength ratio is higher for Grade 2 as compared to Grade 4. % Elongation is found to increase/retained at cryogenic temperatures for Grade 2, and it is found to decrease for Grade 4. Electron backscattered diffraction analysis and transmission electron microscopy of deformed samples confirmed the presence of extensive twinning in Grade 2 and the presence of finer martensitic structure in Grade 4. Fractography analysis of tested specimens revealed the presence of cleavage facets in Grade 4 and dimples in specimens of Grade 2. Higher strength in Grade 4 is attributed to higher oxygen restricting the twin-assisted slip, which is otherwise prominent in Grade 2 titanium.

  10. The speed of gravity in general relativity and theoretical interpretation of the Jovian deflection experiment

    International Nuclear Information System (INIS)

    Kopeikin, Sergei M

    2004-01-01

    According to Einstein, the notions of geodesic, parallel transport (affine connection) and curvature of the spacetime manifold have a pure geometric origin and do not correlate with any electromagnetic concepts. At the same time, curvature is generated by matter which is not affiliated with the spacetime geometric concepts. For this reason, the fundamental constant c entering the geometric and matter sectors of the general theory of relativity has different conceptual meanings. Specifically, the letter c on the left-hand side of the Einstein equations (geometric sector) entering the Christoffel symbols and its time derivatives is the ultimate speed of gravity characterizing the upper limit on the speed of its propagation as well as the maximal rate of change of time derivatives of the metric tensor, that is gravitational field. The letter c on the right-hand side of the Einstein equations (matter sector) is the maximal speed of propagation of any other field rather than gravity. Einstein's general principle of relativity extends his principle of special relativity and equates the numerical value of the ultimate speed of gravity to that of the speed of light in the special theory of relativity but this general principle must be tested experimentally. To this end, we work out the speed of gravity parametrization of the Einstein equations (c g -parametrization) to keep track of the time-dependent effects associated with the geometric sector of general relativity and to separate them from the time-dependent effects of the matter sector. Parametrized post-Newtonian (PPN) approximation of the Einstein equations is derived in order to explain the gravitational physics of the Jovian deflection VLBI experiment conducted on 8 September 2002. The post-Newtonian series expansion in the c g -parametrized general relativity is with respect to a small parameter that is proportional to the ratio of the characteristic velocity of the bodies to the speed of propagation of the

  11. AgraPure Mississippi Biomass Project

    Energy Technology Data Exchange (ETDEWEB)

    Blackwell,D.A; Broadhead, L.W.; Harrell, W.J.

    2006-03-31

    The AgraPure Mississippi Biomass project was a congressionally directed project, initiated to study the utilization of Mississippi agricultural byproducts and waste products in the production of bio-energy and to determine the feasibility of commercialization of these agricultural byproducts and waste products as feedstocks in the production of energy. The final products from this project were two business plans; one for a Thermal plant, and one for a Biodiesel/Ethanol plant. Agricultural waste fired steam and electrical generating plants and biodiesel plants were deemed the best prospects for developing commercially viable industries. Additionally, oil extraction methods were studied, both traditional and two novel techniques, and incorporated into the development plans. Mississippi produced crop and animal waste biomasses were analyzed for use as raw materials for both industries. The relevant factors, availability, costs, transportation, storage, location, and energetic value criteria were considered. Since feedstock accounts for more than 70 percent of the total cost of producing biodiesel, any local advantages are considered extremely important in developing this particular industry. The same factors must be evaluated in assessing the prospects of commercial operation of a steam and electrical generation plant. Additionally, the access to the markets for electricity is more limited, regulated and tightly controlled than the liquid fuel markets. Domestically produced biofuels, both biodiesel and ethanol, are gaining more attention and popularity with the consuming public as prices rise and supplies of foreign crude become less secure. Biodiesel requires no major modifications to existing diesel engines or supply chain and offers significant environmental benefits. Currently the biodiesel industry requires Federal and State incentives to allow the industry to develop and become self-sustaining. Mississippi has available the necessary feedstocks and is

  12. Speeding Fermat's factoring method

    Science.gov (United States)

    McKee, James

    A factoring method is presented which, heuristically, splits composite n in O(n^{1/4+epsilon}) steps. There are two ideas: an integer approximation to sqrt(q/p) provides an O(n^{1/2+epsilon}) algorithm in which n is represented as the difference of two rational squares; observing that if a prime m divides a square, then m^2 divides that square, a heuristic speed-up to O(n^{1/4+epsilon}) steps is achieved. The method is well-suited for use with small computers: the storage required is negligible, and one never needs to work with numbers larger than n itself.

  13. High Speed Photomicrography

    Science.gov (United States)

    Hyzer, William G.

    1983-03-01

    One of the most challenging areas in applying high-speed photography and videography in the plant and laboratory is in the recording of rapid events at macro and microscopic scales. Depth of field, exposure efficiency, working distance, and required exposure time are all reduced as optical magnification is increased, which severely taxes the skill and ingenuity of workers interested in recording any fast moving phenomena through the microscope or with magnifying lenses. This paper defines the problems inherent in photographing within macro and microscopic ranges and offers a systematic approach to optimizing the selection of equipment and choice of applicable techniques.

  14. Speeding Up Innovation

    DEFF Research Database (Denmark)

    Sørensen, Flemming; Mattsson, Jan

    2016-01-01

    Minimisation of time-to-market strategies can provide companies with a competitive advantage in dynamic and competitive environments. Using parallel innovation processes has been emphasised as one strategy to speed up innovation processes and consequently minimise the time-to-market of innovations....... Much innovation today takes place in open structures in which networks play an important role. However, little is known about how innovation networks can facilitate parallel innovation processes. This paper discusses how innovation network structures develop and support exploration and exploitation...... of the network facilitate the parallel innovation process but also how such processes place new requirements on such networks and their management....

  15. High speed rotary drum

    Energy Technology Data Exchange (ETDEWEB)

    Sagara, H

    1970-03-25

    A high speed rotary drum is disclosed in which the rotor vessel is a double-wall structure comprising an inner wave-shaped pipe inserted coaxially within an outer straight pipe, the object being to provide a strengthened composite light-weight structure. Since force induced axial deformation of the straight pipe and radial deformation of the corrugated pipe are small, the composite effectively resists external forces and, if the waves of the inner pipe are given a sufficient amplitude, the thickness of both pipes may be reduced to lower the overall weight. Thus high angular velocities can be obtained to separate U/sup 235/ from gaseous UF/sub 6/.

  16. Speed control variable rate irrigation

    Science.gov (United States)

    Speed control variable rate irrigation (VRI) is used to address within field variability by controlling a moving sprinkler’s travel speed to vary the application depth. Changes in speed are commonly practiced over areas that slope, pond or where soil texture is predominantly different. Dynamic presc...

  17. Safe Speeds and Credible Speed Limits (SaCredSpeed): New Vision for Decision Making on Speed Management.

    NARCIS (Netherlands)

    Aarts, L. Nes, N. van Wegman, F.C.M. Schagen, I.N.L.G. van & Louwerse, R.

    2009-01-01

    Speed is an inherent characteristic of mobility and a hazard to safety. Several approaches exist of how to manage speed. In the Netherlands, the emphasis has mainly been on harm minimisation during the last decades, due to the implementation of the Sustainable Safety vision. Speed management remains

  18. Pay as You Speed, ISA with incentives for not speeding

    DEFF Research Database (Denmark)

    Lahrmann, Harry Spaabæk; Agerholm, Niels; Tradisauskas, Nerius

    2012-01-01

    The Intelligent Speed Adaptation (ISA) project we describe in this article is based on Pay as You Drive principles. These principles assume that the ISA equipment informs a driver of the speed limit, warns the driver when speeding and calculates penalty points. Each penalty point entails the redu......The Intelligent Speed Adaptation (ISA) project we describe in this article is based on Pay as You Drive principles. These principles assume that the ISA equipment informs a driver of the speed limit, warns the driver when speeding and calculates penalty points. Each penalty point entails...... the reduction of a 30% discount on the driver's car insurance premium, which therefore produced the name, Pay as You Speed. The ISA equipment consists of a GPS-based On Board Unit with a mobile phone connection to a web server. The project was planned for a three-year test period with 300 young car drivers...

  19. Two qubits in pure nuclear quadrupole resonance

    International Nuclear Information System (INIS)

    Furman, G.B.; Goren, S.D.; Meerovich, V.M.; Sokolovsky, V.L.

    2002-01-01

    It is shown theoretically that by the use of two radio-frequency fields of the same resonance frequency but with the different phases and directions the degeneracy of the energy spectrum of a spin system with I=3/2 is removed. This leads to four non-degenerate spin states which can be used as a platform for quantum computing. The feasibility of quantum computing based on a pure (without DC magnetic fields) nuclear quadrupole resonance technique is investigated in detail. Various quantum logic gates can be constructed by using different excitation techniques allowing different manipulations with the spin system states. Three realizations of quantum logic gates are considered: the application of an additional magnetic field with the resonance frequency, the amplitude modulation of one of the applied RF fields by the resonance frequency field, and the level-crossing method. It is shown that the probabilities of the resonance transitions depend on the method of excitation and on the direction of the excitation field. Feasibility of quantum computing is demonstrated with the examples of constructing a controlled-NOT logic gate using the resonance excitation technique and SWAP and NOT2 logic gates using the level-crossing method. (author)

  20. Memory for pure tone sequences without contour.

    Science.gov (United States)

    Lefebvre, Christine; Jolicœur, Pierre

    2016-06-01

    We presented pure tones interspersed with white noise sounds to disrupt contour perception in an acoustic short-term memory (ASTM) experiment during which we recorded the electroencephalogram. The memory set consisted of seven stimuli, 0, 1, 2, 3, or 4 of which were to-be-remembered tones. We estimated each participant׳s capacity, K, for each set size and measured the amplitude of the SAN (sustained anterior negativity, an ERP related to acoustic short-term memory). We correlated their K slopes with their SAN amplitude slopes as a function of set size, and found a significant link between performance and the SAN: a larger increase in SAN amplitude was linked with a larger number of stimuli maintained in ASTM. The SAN decreased in amplitude in the later portion of the silent retention interval, but the correlation between the SAN and capacity remained strong. These results show the SAN is not an index of contour but rather an index of the maintenance of individual objects in STM. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Pec power generation system using pure energy

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, K; Sonai, A; Kano, A [Toshiba International Fuel Cells Corp. (Japan). Cell Technology Development Dept.; Yatake, T [Toshiba International Fuel Cells Corp. (Japan). Plant Engineering Dept.

    2002-07-01

    A polymer electrolyte fuel cell (PEFC) power generation system using pure hydrogen was developed by Toshiba International Fuel Cells (TIFC), Japan, under the sponsorship of the World Energy Network (WE-NET) Project. The goals of the project consist of the construction of 30 kilowatt power generation plant for stationary application and target electrical efficiency of over 50 per cent. Two critical technologies were investigated for high utilization stack, as high hydrogen utilization operation represents one of the most important items for the achievement of target efficiency. The first technology examined was the humidification method from cathode side, while the second was the two-block configuration, which is arranged in series in accordance with the flow of hydrogen. Using these technologies as a basis for the work, a 5 kilowatt short stack was developed, and a steady performance was obtained under high hydrogen utilization of up to 98 per cent. It is expected that by March 2003 the design of the hydrogen fueled 30 kilowatt power generation plant will be completed and assembled. 1 ref., 1 tab., 11 figs.

  2. Electron Acoustic Waves in Pure Ion Plasmas

    Science.gov (United States)

    Anderegg, F.; Affolter, M.; Driscoll, C. F.; O'Neil, T. M.; Valentini, F.

    2012-10-01

    Electron Acoustic Waves (EAWs) are the low-frequency branch of near-linear Langmuir (plasma) waves: the frequency is such that the complex dielectric function (Dr, Di) has Dr= 0; and ``flattening'' of f(v) near the wave phase velocity vph gives Di=0 and eliminates Landau damping. Here, we observe standing axisymmetric EAWs in a pure ion column.footnotetextF. Anderegg, et al., Phys. Rev. Lett. 102, 095001 (2009). At low excitation amplitudes, the EAWs have vph˜1.4 v, in close agreement with near-linear theory. At moderate excitation strengths, EAW waves are observed over a range of frequencies, with 1.3 v vphvph.footnotetextF. Valentini et al., arXiv:1206.3500v1. Large amplitude EAWs have strong phase-locked harmonic content, and experiments will be compared to same-geometry simulations, and to simulations of KEENfootnotetextB. Afeyan et al., Proc. Inertial Fusion Sci. and Applications 2003, A.N.S. Monterey (2004), p. 213. waves in HEDLP geometries.

  3. Homogeneous purely buoyancy driven turbulent flow

    Science.gov (United States)

    Arakeri, Jaywant; Cholemari, Murali; Pawar, Shashikant

    2010-11-01

    An unstable density difference across a long vertical tube open at both ends leads to convection that is axially homogeneous with a linear density gradient. We report results from such tube convection experiments, with driving density caused by salt concentration difference or temperature difference. At high enough Rayleigh numbers (Ra) the convection is turbulent with zero mean flow and zero mean Reynolds shear stresses; thus turbulent production is purely by buoyancy. We observe different regimes of turbulent convection. At very high Ra the Nusselt number scales as the square root of the Rayleigh number, giving the so-called "ultimate regime" of convection predicted for Rayleigh-Benard convection in limit of infinite Ra. Turbulent convection at intermediate Ra, the Nusselt number scales as Ra^0.3. In both regimes, the flux and the Taylor scale Reynolds number are more than order of magnitude larger than those obtained in Rayleigh-Benard convection. Absence of a mean flow makes this an ideal flow to study shear free turbulence near a wall.

  4. Radiation resisting features of pure quartz fiber

    International Nuclear Information System (INIS)

    Fujii, Takashi; Nagasawa, Yoshiya; Hoshi, Hiroshi; Tomon, Ryoichi; Ooki, Yoshimichi; Yahagi, Kichinosuke

    1985-01-01

    The control of the generation of color centers is essential for optical fibers used in radiation environment. Even pure quartz which is the best radiation resisting material is not exceptional also elucidarion of the mechanism of the generation of color center is necessary for the development of optical fiber with higher radiation resisting feature. Previously, it was assumed that color centers are distributed uniformly throughout cores. Determination of the distribution of color centers was attempted. Cores were etched with HF after γ-ray irradiation, and the changes of intensity of ESR signals of NBOHC and E'-center were determined. NBOHC were not found in circumferential part, and concentrated in the central part. In other words the tendency of distribution is diametral. Thus, the distribution of precursor is supposed to be affected by certain external cause and the generation of NBOHC was depressed in circumferential area. The distribution of E'-center of high OH sample showed similar tendency and high in the center. Where as the distribution in low OH sample was uniform. The external cause is supposed to be hydrogen derived from silicone clad and silicone buffer. Two kind of precursor is suspected for the explanation of the difference of the E'-center in high OH sample and low OH sample. (Ishimitsu, A.)

  5. The outflow speed of the coma of Halley's comet

    International Nuclear Information System (INIS)

    Combi, M.R.

    1989-01-01

    Data concerning the outflow speed of the coma of Comet Halley are studied in relation to a generalization of the coupled pure-gas-dynamic/Monte Carlo model of Combi and Smyth (1988) to include the dusty-gas dynamics of the inner coma. Measurements made by the Giotto neutral-gas spectrometer, IR water observations from the Kuiper Airborne Observatory, and Doppler radio line profiles of HCN and OH are used to examine the radial dependence of the outflow speed, the asymmetry in the outflow speed, and the overall heliocentric distance dependence of the Doppler profiles, respectively. The results suggest that the model makes it possible to understand the gross long-term behavior and radial structure of the dynamics of the cometary coma. 23 refs

  6. Peccei-Quinn symmetric pure gravity mediation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Jason L.; Olive, Keith A. [University of Minnesota, William I. Fine Theoretical Physics Institute, School of Physics and Astronomy, Minneapolis, MN (United States); Ibe, Masahiro [University of Tokyo, ICRR, Kashiwa (Japan); University of Tokyo, Kavli IPMU (WPI), TODIAS, Kashiwa (Japan); Yanagida, Tsutomu T. [University of Tokyo, Kavli IPMU (WPI), TODIAS, Kashiwa (Japan)

    2014-07-15

    Successful models of pure gravity mediation (PGM) with radiative electroweak symmetry breaking can be expressed with as few as two free parameters, which can be taken as the gravitinomass and tan β. These models easily support a 125-126 GeV Higgs mass at the expense of a scalar spectrum in the multi-TeV range and a much lighter wino as the lightest supersymmetric particle. In these models, it is also quite generic that the Higgs mixing mass parameter, μ, which is determined by the minimization of the Higgs potential is also in the multi-TeV range. For μ > 0, the thermal relic density of winos is too small to account for the darkmatter. The same is true for μ < 0 unless the gravitinomass is of order 500 TeV. Here, we consider the origin of a multi-TeV μ parameter arising from the breakdown of a Peccei-Quinn (PQ) symmetry. A coupling of the PQ-symmetry breaking field, P, to the MSSM Higgs doublets, naturally leads to a value of μ ∝ left angle P right angle {sup 2}/M{sub P} ∝ O(100) TeV and of the order that is required in PGM models. In this case, axions make up the dark matter or some fraction of the dark matter with the remainder made up from thermal or non-thermal winos. We also provide solutions to the problem of isocurvature fluctuations with axion dark matter in this context. (orig.)

  7. Pure analgesics in a rheumatological outpatient clinic

    Directory of Open Access Journals (Sweden)

    M.A. Cimmino

    2011-09-01

    Full Text Available Objective: Pure analgesics are only rarely used by Italian clinicians and this holds true also for rheumatologists. This work is concerned with an evaluation of the use of analgesics in a rheumatological outpatient clinic during the period 1989-1999. Methods: The records of 1705 patients consecutively seen at the clinic were downloaded on a specifically built website. Results: 4469 visits were considered. In 260 of them (5.8%, analgesics were prescribed to 234 (13.7% patients. The number of patients with a prescription of analgesics steadily increased during the years 1989-1999. The diagnoses in patients assuming analgesics were: osteoarthritis (47.1%, inflammatory arthritis (24.2%, soft tissue rheumatisms (13.7%, nonspecific arthralgia/myalgia (7.5%, and connective tissue diseases (2.6%. Peripheral analgesics were used in 188 (82.5% patients and central analgesics were used in the remaining 40 patients (17.5%. Analgesic drugs were used mainly in degenerative joint conditions. The indications for analgesics in the 55 patients with inflammatory arthrits were: (a partial or total remission of arthritis; for this reason non-steroidal anti-inflammatory drugs were no longer required in 18 patients; (b to increase the analgesic effect of NSAIDs in 23 patients; (c contraindications to NSAIDs in 14 patients (renal failure in 2 patients, gastritis in 10, allergy and bleeding in the remaining two. Conclusions: About 14% of our outpatients were treated with analgesics with an increasing trend in the examined period. The main indications for analgesics are degenerative conditions but they can be used also in selected patients with arthritis.

  8. Heat of combustion, sound speed and component fluctuations in natural gas

    International Nuclear Information System (INIS)

    Burstein, L.; Ingman, D.

    1998-01-01

    The heat of combustion and sound speed of natural gas were studied as a function of random fluctuation of the gas fractions. A method of sound speed determination was developed and used for over 50,000 possible variants of component concentrations in four- and five- component mixtures. A test on binary (methane-ethane) and multicomponent (Gulf Coast) gas mixtures under standard pressure and moderate temperatures shows satisfactory predictability of sound speed on the basis of the binary virial coefficients, sound speeds and heat capacities of the pure components. Uncertainty in the obtained values does not exceed that of the pure component data. The results of comparison between two natural gas mixtures - with and without nonflammable components - are reported

  9. ActionScript Developer's Guide to PureMVC

    CERN Document Server

    Hall, Cliff

    2011-01-01

    Gain hands-on experience with PureMVC, the popular open source framework for developing maintainable applications with a Model-View-Controller architecture. In this concise guide, PureMVC creator Cliff Hall teaches the fundamentals of PureMVC development by walking you through the construction of a complete non-trivial Adobe AIR application. Through clear explanations and numerous ActionScript code examples, you'll learn best practices for using the framework's classes in your day-to-day work. Discover how PureMVC enables you to focus on the purpose and scope of your application, while the f

  10. Pure transvaginal excision of mesh erosion involving the bladder.

    Science.gov (United States)

    Firoozi, Farzeen; Goldman, Howard B

    2013-06-01

    We present a pure transvaginal approach to the removal of eroded mesh involving the bladder secondary to placement of transvaginal mesh for management of pelvic organ prolapse (POP) using a mesh kit. Although technically challenging, we demonstrate the feasibility of a purely transvaginal approach, avoiding a potentially more morbid transabdominal approach. The video presents the surgical technique of pure transvaginal excision of mesh erosion involving the bladder after mesh placement using a prolapse kit was performed. This video shows that purely transvaginal removal of mesh erosion involving the bladder can be done safely and is feasible.

  11. Speed control at low wind speeds for a variable speed fixed pitch wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Rosmin, N.; Watson, S.J.; Tompson, M. [Loughborough Univ., Loughborough, Leicestershire (United Kingdom)

    2010-03-09

    The maximum power regulation below rated wind speed is regulated by changing the rotor/generator speed at large frequency range in a fixed pitch, variable speed, stall-regulated wind turbine. In order to capture the power at a maximum value the power coefficient is kept at maximum peak point by maintaining the tip speed ratio at its optimum value. The wind industry is moving from stall regulated fixed speed wind turbines to newer improved innovative versions with better reliability. While a stall regulated fixed pitch wind turbine is among the most cost-effective wind turbine on the market, its problems include noise, severe vibrations, high thrust loads and low power efficiency. Therefore, in order to improve such drawbacks, the rotation of the generator speed is made flexible where the rotation can be controlled in variable speed. This paper discussed the development of a simulation model which represented the behaviour of a stall regulated variable speed wind turbine at low wind speed control region by using the closed loop scalar control with adjustable speed drive. The paper provided a description of each sub-model in the wind turbine system and described the scalar control of the induction machine. It was concluded that by using a constant voltage/frequency ratio of the generator's stator side control, the generator speed could be regulated and the generator torque could be controlled to ensure the power coefficient could be maintained close to its maximum value. 38 refs., 1 tab., 10 figs.

  12. Structural, optical and dielectric properties of pure and chromium (Cr) doped nickel oxide nanoparticles

    Science.gov (United States)

    Gupta, Jhalak; Ahmed, Arham S.

    2018-05-01

    The pure and Cr doped nickel oxide (NiO) nanoparticles have been synthesized by cost effective co-precipitation method having nickel nitrate as initial precursor. The synthesized samples were characterized by X-Ray diffraction (XRD), UV-Visible Spectroscopy(UV-Vis) and LCR meter for structural, optical and dielectric properties respectively. The crystallite size of pure nickel oxide nanoparticles characterized by XRD using Debye Scherer's formula was found to be 21.7nm and the same decreases on increasing Cr concentration whereas optical and dielectric properties were analyzed by UV-Vis and LCR meter respectively. The energy band gaps were determined by UV-Vis using Tauc relation.

  13. Is the propagation speed of ultrasound in human organs a diagnostic parameter for tissue characterization? Evaluation using the liver parenchyma in children and adolescents as an example; Die Schallleitgeschwindigkeit im menschlichen Gewebe. Ein diagnostisch verwertbarer Parameter? Evaluation am Beispiel der Leber bei Kindern und Jugendlichen

    Energy Technology Data Exchange (ETDEWEB)

    Born, M. [Bonn Univ. (Germany). Radiologische Klinik - Kinderradiologie; Franke, I. [Bonn Univ. (Germany). Kinderklinik

    2011-09-15

    New sonographic machines permit the measurement of the propagation speed of ultrasound (PSU) in humans. The liver seems to be an appropriate organ for examining whether the PSU may be used as a diagnostic parameter for tissue characterization since the liver is easily accessible to sonography and its variable content of fat impacts the PSU. Purpose: To determine whether there is a measurable correlation between obesity and PSU in the liver. Methods: In 69 children and adolescents, the PSU in the liver was measured sonographically and correlated to BMI, age, size and weight of the children. Results: A strong correlation was found between the PSU in the liver and the BMI. The PSU was significantly lower in obese children (1507 m/s) than in children with normal body weight (1564 m/s). Conclusion: PSU seems to be promising as an additional diagnostic parameter for characterizing liver tissue. Further evaluation is necessary. (orig.)

  14. MRI appearances of pure epithelial papillary serous borderline ovarian tumours

    International Nuclear Information System (INIS)

    Naqvi, J.; Nagaraju, E.; Ahmad, S.

    2015-01-01

    Borderline epithelial ovarian tumours (BOT) represent 15–20% of all non-benign ovarian epithelial neoplasms. Compared to malignant ovarian tumours, they usually present at a younger age and carry a far superior prognosis. Fertility-conserving surgery is an important treatment option for patients with BOT. Ultrasound and CT are both widely available and play roles in the initial investigation and staging of BOT, respectively. However, lack of soft-tissue contrast limits their ability to characterize BOT. MRI can facilitate recognition of pure epithelial serous BOT (SBOT), including the cystic papillary and surface papillary subtypes. An abundance of hyperintense papillary projections with low signal internal branching and ovarian stroma preservation with a hypointense ovarian capsular margin on T2-weighted imaging are features strongly suggestive of SBOT. In this review we will discuss the general morphological features of SBOT, the benefits and drawbacks of ultrasound and CT in the initial work-up, and the principal MRI features enabling recognition of surface papillary and cystic papillary SBOT

  15. Coating of hydroxyapatite doped Ag on commercially pure titanium surface

    International Nuclear Information System (INIS)

    Vieira, Jonas de Oliveira; Vercik, Luci Cristina de Oliveira; Rigo, Eliana Cristina da Silva

    2012-01-01

    This paper presents results of bioactive coating on commercially pure titanium surface (CpTi) doped with Ag ions. The coating consists of 3 steps, in step 1- surface chemical treatment of the samples with NaOH, step 2 - immersing the substrate in question in a sodium silicate solution (SS) to the nucleation and step 3 - reimmersion these substrates in synthetic solution that simulates the blood serum for precipitation and growth of apatite layer. After the coating step the AgNO 3 substrates were immersed in solutions with concentrations of 20 ppm and 100 ppm at 37 ° C for 48h. The substrates were characterized by scanning electron microscopy (SEM), infrared spectroscopy (IR) and X-ray diffraction (XRD). By the results verified the formation of an apatite layer with aspects of cells, on the surface of CpTi. The increase in Ag concentration causes an increase in Ag amount doped in apatite layer. With the results we concluded that it is possible to obtain an apatite layer on a metal surface as the CpTi doped with Ag ions

  16. Multicopy and stochastic transformation of multipartite pure states

    International Nuclear Information System (INIS)

    Chen Lin; Hayashi, Masahito

    2011-01-01

    Characterizing the transformation and classification of multipartite entangled states is a basic problem in quantum information. We study the problem under the two most common environments, local operations and classical communications (LOCC), stochastic LOCC and two more general environments, multicopy LOCC (MCLOCC), and multicopy SLOCC (MCSLOCC). We show that two transformable multipartite states under LOCC or SLOCC are also transformable under MCLOCC and MCSLOCC. What is more, these two environments are equivalent in the sense that two transformable states under MCLOCC are also transformable under MCSLOCC, and vice versa. Based on these environments we classify the multipartite pure states into a few inequivalent sets and orbits, between which we build the partial order to decide their transformation. In particular, we investigate the structure of SLOCC-equivalent states in terms of tensor rank, which is known as the generalized Schmidt rank. Given the tensor rank, we show that Greenberger-Horne-Zeilinger states can be used to generate all states with a smaller or equivalent tensor rank under SLOCC, and all reduced separable states with a cardinality smaller than or equivalent to the tensor rank under LOCC. Using these concepts, we extended the concept of the ''maximally entangled state'' in the multipartite system.

  17. Preparation Of Pure Carbon From Heavy Oil Fly Ash

    International Nuclear Information System (INIS)

    ABU ZAID, A.H.M.

    2010-01-01

    The Egyptian production of heavy oil is approximately 12 million tons of heavy oil per year and approximately 5.3 million tons of this amount is used as fuel in the electric power stations. Based on the fact that the ash content of Egyptian heavy oil is approximately 0.2 %, about 10600 tons of fly ash is produced per/year which causes a lot of environmental problems such as dusting, release of the acidic liquids and heavy metals such as vanadium, nickel, zinc and unburned carbon. Treatment of fly ash by leaching of vanadium and zinc was carried out under different conditions to achieve the best leaching efficiency of both vanadium and zinc by sodium hydroxide. The leaching efficiency obtained was 91% for vanadium and 98% for zinc. This study was concerned with the precipitation of zinc at pH 7.5 as zinc hydroxide and the precipitation of vanadium as ammonium metavanadate at pH 8.5. Leaching of nickel, iron and other elements from the residue was carried out by 2M HCl under different conditions. The achieved leaching efficiency of nickel was 95% where as that of iron was 92%. Precipitation efficiency of both nickel and iron were 99.9%. The residue, which contains mainly unburned carbon, have been washed two times with water and dried at 200 o C then ground to < 300μm. According to the achieved analysis of the obtained carbon, it can be characterized as pure carbon

  18. Risk-Sensitive Control of Pure Jump Process on Countable Space with Near Monotone Cost

    International Nuclear Information System (INIS)

    Suresh Kumar, K.; Pal, Chandan

    2013-01-01

    In this article, we study risk-sensitive control problem with controlled continuous time pure jump process on a countable space as state dynamics. We prove multiplicative dynamic programming principle, elliptic and parabolic Harnack’s inequalities. Using the multiplicative dynamic programing principle and the Harnack’s inequalities, we prove the existence and a characterization of optimal risk-sensitive control under the near monotone condition

  19. Estimation of effective wind speed

    Science.gov (United States)

    Østergaard, K. Z.; Brath, P.; Stoustrup, J.

    2007-07-01

    The wind speed has a huge impact on the dynamic response of wind turbine. Because of this, many control algorithms use a measure of the wind speed to increase performance, e.g. by gain scheduling and feed forward. Unfortunately, no accurate measurement of the effective wind speed is online available from direct measurements, which means that it must be estimated in order to make such control methods applicable in practice. In this paper a new method is presented for the estimation of the effective wind speed. First, the rotor speed and aerodynamic torque are estimated by a combined state and input observer. These two variables combined with the measured pitch angle is then used to calculate the effective wind speed by an inversion of a static aerodynamic model.

  20. High-speed AC motors

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, T.; Arkkio, A. [Helsinki University of Technology Laboratory of Electromechanics, Otaniemi (Finland)

    1997-12-31

    The paper deals with various types of highspeed electric motors, and their limiting powers. Standard machines with laminated rotors can be utilised if the speed is moderate. The solid rotor construction makes it possible to reach higher power and speed levels than those of laminated rotors. The development work on high-speed motors done at Helsinki University of Technology is presented, too. (orig.) 12 refs.

  1. Pure Electric and Pure Magnetic Resonances in Near-Infrared Metal Double-Triangle Metamaterial Arrays

    International Nuclear Information System (INIS)

    Cao Zhi-Shen; Pan Jian; Chen Zhuo; Zhan Peng; Min Nai-Ben; Wang Zhen-Lin

    2011-01-01

    We experimentally and numerically investigate the optical properties of metamaterial arrays composed of double partially-overlapped metallic nanotriangles fabricated by an angle-resolved nanosphere lithography. We demonstrate that each double-triangle can be viewed as an artificial magnetic element analogous to the conventional metal split-ring-resonator. It is shown that under normal-incidence conditions, individual double-triangle can exhibit a strong local magnetic resonance, but the collective response of the metamaterial arrays is purely electric because magnetic resonances of the two double-triangles in a unit cell having opposite openings are out of phase. For oblique incidences the metamaterial arrays are shown to support a pure magnetic response at the same frequency band. Therefore, switchable electric and magnetic resonances are achieved in double-triangle arrays. Moreover, both the electric and magnetic resonances are shown to allow for a tunability over a large spectral range down to near-infrared. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  2. Wind speed perception and risk.

    Directory of Open Access Journals (Sweden)

    Duzgun Agdas

    Full Text Available BACKGROUND: How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. METHOD: We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. RESULTS: Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk. The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. CONCLUSION: These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  3. Wind speed perception and risk.

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D; Masters, Forrest J

    2012-01-01

    How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  4. Wind Speed Perception and Risk

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D.; Masters, Forrest J.

    2012-01-01

    Background How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human–wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. Method We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Results Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual–perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. Conclusion These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters. PMID:23226230

  5. Bi-orderings on pure braided Thompson's groups

    OpenAIRE

    Burillo, Jose; Gonzalez-Meneses, Juan

    2006-01-01

    In this paper it is proved that the pure braided Thompson’s group BF admits a bi-order, analog to the bi-order of the pure braid groups. Ministerio de Educación y Ciencia Fondo Europeo de Desarrollo Regional

  6. AdS pure spinor superstring in constant backgrounds

    International Nuclear Information System (INIS)

    Chandia, Osvaldo; Bevilaqua, L. Ibiapina; Vallilo, Brenno Carlini

    2014-01-01

    In this paper we study the pure spinor formulation of the superstring in AdS_5×S"5 around point particle solutions of the classical equations of motion. As a particular example we quantize the pure spinor string in the BMN background

  7. Pure soliton solutions of some nonlinear partial differential equations

    International Nuclear Information System (INIS)

    Fuchssteiner, B.

    1977-01-01

    A general approach is given to obtain the system of ordinary differential equations which determines the pure soliton solutions for the class of generalized Korteweg-de Vries equations. This approach also leads to a system of ordinary differential equations for the pure soliton solutions of the sine-Gordon equation. (orig.) [de

  8. Graph Theory to Pure Mathematics: Some Illustrative Examples

    Indian Academy of Sciences (India)

    Graph Theory to Pure Mathematics: Some. Illustrative Examples v Yegnanarayanan is a. Professor of Mathematics at MNM Jain Engineering. College, Chennai. His research interests include graph theory and its applications to both pure maths and theoretical computer science. Keywords. Graph theory, matching theory,.

  9. AdS pure spinor superstring in constant backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Chandia, Osvaldo [Departamento de Ciencias, Facultad de Artes Liberales, Universidad Adolfo Ibáñez,Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez,Diagonal Las Torres 2640, Peñalolén, Santiago (Chile); Bevilaqua, L. Ibiapina [Escola de Ciências e Tecnologia, Universidade Federal do Rio Grande do Norte,Caixa Postal 1524, 59072-970, Natal, RN (Brazil); Vallilo, Brenno Carlini [Facultad de Ciencias Exactas, Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile)

    2014-06-05

    In this paper we study the pure spinor formulation of the superstring in AdS{sub 5}×S{sup 5} around point particle solutions of the classical equations of motion. As a particular example we quantize the pure spinor string in the BMN background.

  10. Nigeria Journal of Pure and Applied Physics: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. Nigeria Journal of Pure and Applied Physics publishes papers of the highest quality and significance in specific areas of physics, pure and applied, as listed below. The journal content reflects core physics disciplines, but is also open to a broad range of topics whose central theme falls within the bounds ...

  11. Preparation and characterization of phase-pure anatase and rutile TiO{sub 2} powder by new chemistry route; Preparacao e caracterizacao de nanoparticulas de TiO{sub 2} nas fases anatase e rutila por uma nova rota quimica

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, E. A.; Montanhera, M.A.; Paula, F.R., E-mail: sevlarede2@yahoo.com.br [Universidade Estadual Paulista Julio de Mesquista Filho (UNESP), Ilha Soltiera, SP (Brazil). Faculdade de Engenharia. Departameinto de Fisica e Quimica; Spada, E.R. [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Institutlo de Fisica

    2014-07-01

    Titanium dioxide (TiO{sub 2}) is used in a wire range applications such as photocatalysis and sensor device. In this work is shown a new and effective method for the preparation of TiO{sub 2} nanocrystalline in the crystallographic forms, anatase and rutile. The method involves dissolving the TiOSO{sub 4} powder in H{sub 2}O{sub 2} solution and thermal treatment of amorphous precipitate. The technique of X-ray diffraction was used to follow the structure evolution of amorphous precipitate. Pure anatase structure and rutile are obtained at 600 deg C and 1000 deg C with a grain size estimated 24 and 55 nm respectively. TiO{sub 2} nanoparticles is a promising alternative of the low cost whose potential for solar cells deserve a careful evaluation, especially in hybrid solar cells that employs TiO{sub 2} as electron acceptor and as transport channels. (author)

  12. Pay as You Speed, ISA with incentive for not speeding

    DEFF Research Database (Denmark)

    Lahrmann, Harry Spaabæk; Agerholm, Niels; Tradisauskas, Nerius

    2012-01-01

    To simulate a market introduction of Intelligent Speed Adaptation (ISA) and to study the effect of a Pay as You Speed (PAYS) concept, a field trial with 153 drivers was conducted during 2007–2009. The participants drove under PAYS conditions for a shorter or a longer period. The PAYS concept......, with and without incentive crossed with informative ISA present or absent. The results showed that ISA is an efficient tool for reducing speeding particularly on rural roads. The analysis of speed data demonstrated that the proportion of distance driven above the speed where the ISA equipment responded (PDA...... level. Both informative ISA and incentive ISA reduced the PDA, but there was no statistically significant interaction. Informative reduced it more than the incentive....

  13. Indigenously developed large pumping speed cryoadsorption cryopump

    International Nuclear Information System (INIS)

    Gangradey, Ranjana; Mukherjee, Samiran Shanti; Agarwal, Jyoti

    2015-01-01

    Indigenous cryoadsorption cryopump with large pumping speeds for fusion reactor application has been developed at the Institute for Plasma Research (IPR). Towards its successful realization, technological bottlenecks were identified, studied and resolved. Hydroformed cryopanels were developed from concept leading to the design and product realization with successful technology transfer to the industry. This has led to the expertise for developing hydroformed panels for any desired shape, geometry and welding pattern. Activated sorbents were developed, characterized using an experimental set up which measures adsorption isotherms down to 4K for hydrogen and helium. Special techniques were evolved for coating sorbents on hydroformed cryopanels with suitable cryo-adhesives. Various arrangements of cryopanels at 4 K surrounded by 80 K shields and baffles (which are also hydroformed) were studied and optimized by transmission probability analysis using Monte Carlo techniques. CFD analysis was used to study the temperature distribution and flow analysis during the cryogen flow through the panels. Integration of the developed technologies to arrive at the final product was a challenging task and this was meticulously planned and executed. This resulted in a cryoadsorption cryopump offering pumping speeds as high as 50,000 to 70,000 1/s for helium and 1,50,000 1/s for hydrogen with a 3.2 m 2 of sorbent panel area. The first laboratory scale pump integrating the developed technologies was a Small Scale CryoPump (SSCP-01) with a pumping speed of 2,000 1/s for helium. Subsequently, Single Panel CryoPump (SPCP-01) with pumping speed 10,000 1/s for helium and a Multiple Panel CryoPump (MPCP-08) with a pumping speed of 70,000 1/s for helium and 1,50,000 1/s for hydrogen respectively were developed. This paper describes the efforts in realizing these products from laboratory to industrial scales. (author)

  14. Speed Estimation in Geared Wind Turbines Using the Maximum Correlation Coefficient

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Marhadi, Kun S.; Jensen, Bogi Bech

    2015-01-01

    to overcome the above mentioned issues. The high speed stage shaft angular velocity is calculated based on the maximum correlation coefficient between the 1 st gear mesh frequency of the last gearbox stage and a pure sinus tone of known frequency and phase. The proposed algorithm utilizes vibration signals...

  15. Structural and optical properties of pure and copper doped zinc oxide nanoparticles

    Science.gov (United States)

    Sajjad, Muhammad; Ullah, Inam; Khan, M. I.; Khan, Jamshid; Khan, M. Yaqoob; Qureshi, Muhammad Tauseef

    2018-06-01

    Pure and copper-doped zinc oxide nanoparticles (NPs) have been synthesized via chemical co-precipitation method where hydrazine is used as reducing agent and aqueous extract of Euphorbia milii plant as capping agent. Main objectives of the reported work are to investigate the effect of copper doping on crystal structure of ZnO nanoparticles; to study the effect of copper doping on optical band gap of ZnO nanoparticles and photoluminescence (PL) study of pure and copper-doped ZnO nanoparticles. To achieve the aforementioned objectives, XRD and SEM tests were performed for the identification and confirmation of crystal structure and morphology of the prepared samples. From XRD data the average grain size for pure ZnO was observed to be 24.62 nm which was first decreased to 18.95 nm for 5 wt% Cu-doped sample and then it was found to increase up to 37.80 nm as the Cu doping was increased to 7 wt%. Optical band gap of pure and Cu-doped ZnO nanoparticles was calculated from diffuse reflectance spectroscopy (DRS) spectra and was found to decrease from 3.13 eV to 2.94 eV as the amount of Cu increases up to 7 wt%. In photoluminescence study, PL technique was used and enhanced visible spectrum was observed. For further characterization FT-IR and EDX tests were also carried out.

  16. Quality assessment of biodiesels obtained from pure cooking oils of some feedstocks and their waste oils

    International Nuclear Information System (INIS)

    Khan, I.; Ansari, T.M.; Manzoor, S.

    2017-01-01

    Biodiesel being a renewable energy resource possesses compositional variability based on the type of feedstock. Biodiesel is considered a cleaner burning fuel and can be used as pure B100 or blended with petro-diesel. In this study, biodiesel was prepared from pure cooking oils (soybean oil, canola oil, sunflower oil, corn oil) and their waste frying oils by base-catalyzed transesterification with methanol in presence of sodium hydroxide. The optimized experimental parameters were applied to achieve the maximum yield of biodiesel. Various fuel properties like kinematic viscosity, flash point, pour point, cloud point, total acid number, specific gravity, water and sediments, conradson carbon residue, sulfur contents, phosphorous contents, sulphated ash, cetane and copper corrosion were determined and found comparable to ASTM standards. Pure cooking oils, their waste frying oils and prepared biodiesels were characterized by FT-IR. The study showed that the biodiesel derived from waste frying oils can be a promising alternative of the biodiesel from pure cooking oils. (author)

  17. Low-Temperature Blanching as a Tool to Modulate the Structure of Pectin in Blueberry Purees.

    Science.gov (United States)

    Chevalier, Laura M; Rioux, Laurie-Eve; Angers, Paul; Turgeon, Sylvie L

    2017-09-01

    Blueberry composition was characterized for 6 cultivars. It contains a good amount of dietary fiber (10% to 20%) and pectin (4% to 7%) whose degree of methylation (DM) is sensitive to food processing. A low temperature blanching (LTB: 60 °C/1 h) was applied on blueberry purees to decrease pectin DM, in order to modulate puree properties and functionalities (that is, viscosity and stability), and to enhance pectin affinity toward other components within food matrices. Fiber content, viscosity, pectin solubility, DM, and monosaccharide composition were determined for both pasteurized, and LTB+pasteurized blueberry purees. The results showed that neither the amount of fiber, nor the viscosity were affected by LTB, indicating that this treatment did not result in any significant pectin depolymerization and degradation. LTB caused a decrease both in pectin DM from 58-67% to 45-47% and in the amount of water-soluble pectin fraction, the latter remaining the major fraction of total pectin at 52% to 57%. A LTB is a simple and mild process to produce blueberry purees with mostly soluble and low-methylated pectin in order to extend functionality and opportunities for interactions with other food ingredients. © 2017 Institute of Food Technologists®.

  18. An improved measurement system for FOG pure lag time with no changing of FOG work status

    Science.gov (United States)

    Chen, X.; Yang, J. H.; Zhou, Y. L.; Shu, X. W.

    2018-05-01

    The minimum pure lag time is an important factor for characterizing the dynamic performance of fiber optical gyroscope. It is defined as the time duration from the reception of velocity-shock signal to the output of corresponding fiber-optic gyroscope data. Many engineering projects have required for this index specifically, so the measurement of the minimum pure lag time is highly demanded. In typically measurement system, the work status of tested FOG has to be changed. In this work, a FOG pure lag time measurement system without changing the work status of the FOG has been demonstrated. During the operation of this test system, the impact structure generated a shock towards the FOG, and the pure lag time was measured through data processing analysis. The design scheme and test principle have been researched and analyzed in detail. And a prototype has been developed and used for experiment successfully. This measurement system can realize a measurement accuracy of better than ±3 μs and a system resolution of 108.6ns.

  19. Optimal Speed Control for Cruising

    DEFF Research Database (Denmark)

    Blanke, M.

    1994-01-01

    With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability......With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability...

  20. NTF – wind speed comparison

    DEFF Research Database (Denmark)

    Vesth, Allan; Gómez Arranz, Paula

    The report describes measurements carried out on a given turbine. A comparison between wind speed on the met mast and Nacelle Wind speed are made and the results are presented on graphs and in a table. The data used for the comparison are the data that are same as used for the power curve report...

  1. Comparative in vitro biocompatibility of nickel-titanium, pure nickel, pure titanium, and stainless steel: genotoxicity and atomic absorption evaluation.

    Science.gov (United States)

    Assad, M; Lemieux, N; Rivard, C H; Yahia, L H

    1999-01-01

    The genotoxicity level of nickel-titanium (NiTi) was compared to that of its pure constituents, pure nickel (Ni) and pure titanium (Ti) powders, and also to 316L stainless steel (316L SS) as clinical reference material. In order to do so, a dynamic in vitro semiphysiological extraction was performed with all metals using agitation and ISO requirements. Peripheral blood lymphocytes were then cultured in the presence of all material extracts, and their comparative genotoxicity levels were assessed using electron microscopy-in situ end-labeling (EM-ISEL) coupled to immunogold staining. Cellular chromatin exposition to pure Ni and 316L SS demonstrated a significantly stronger gold binding than exposition to NiTi, pure Ti, or the untreated control. In parallel, graphite furnace atomic absorption spectrophotometry (AAS) was also performed on all extraction media. The release of Ni atoms took the following decreasing distribution for the different resulting semiphysiological solutions: pure Ni, 316L SS, NiTi, Ti, and controls. Ti elements were detected after elution of pure titanium only. Both pure titanium and nickel-titanium specimens obtained a relative in vitro biocompatibility. Therefore, this quantitative in vitro study provides optimistic results for the eventual use of nickel-titanium alloys as surgical implant materials.

  2. Mixture distributions of wind speed in the UAE

    Science.gov (United States)

    Shin, J.; Ouarda, T.; Lee, T. S.

    2013-12-01

    Wind speed probability distribution is commonly used to estimate potential wind energy. The 2-parameter Weibull distribution has been most widely used to characterize the distribution of wind speed. However, it is unable to properly model wind speed regimes when wind speed distribution presents bimodal and kurtotic shapes. Several studies have concluded that the Weibull distribution should not be used for frequency analysis of wind speed without investigation of wind speed distribution. Due to these mixture distributional characteristics of wind speed data, the application of mixture distributions should be further investigated in the frequency analysis of wind speed. A number of studies have investigated the potential wind energy in different parts of the Arabian Peninsula. Mixture distributional characteristics of wind speed were detected from some of these studies. Nevertheless, mixture distributions have not been employed for wind speed modeling in the Arabian Peninsula. In order to improve our understanding of wind energy potential in Arabian Peninsula, mixture distributions should be tested for the frequency analysis of wind speed. The aim of the current study is to assess the suitability of mixture distributions for the frequency analysis of wind speed in the UAE. Hourly mean wind speed data at 10-m height from 7 stations were used in the current study. The Weibull and Kappa distributions were employed as representatives of the conventional non-mixture distributions. 10 mixture distributions are used and constructed by mixing four probability distributions such as Normal, Gamma, Weibull and Extreme value type-one (EV-1) distributions. Three parameter estimation methods such as Expectation Maximization algorithm, Least Squares method and Meta-Heuristic Maximum Likelihood (MHML) method were employed to estimate the parameters of the mixture distributions. In order to compare the goodness-of-fit of tested distributions and parameter estimation methods for

  3. Process Parameters Optimization for Friction Stir Welding of Pure Aluminium to Brass (CuZn30 using Taguchi Technique

    Directory of Open Access Journals (Sweden)

    Elfar O. M. R.

    2016-01-01

    Full Text Available In this research, the friction stir welding of dissimilar commercial pure aluminium and brass (CuZn30 plates was investigated and the process parameters were optimized using Taguchi L9 orthogonal array. The considered process parameters were the rotational speed, traverse speed and pin offset. The optimum setting was determined with reference to ultimate tensile strength of the joint. The predicted optimum value of ultimate tensile strength was confirmed by experimental run using optimum parameters. Analysis of variance revealed that traverse speed is the most significant factor in controlling the joint tensile strength and pin offset also plays a significant role. In this investigation, the optimum tensile strength is 50% of aluminium base metal. Metallographic examination revealed that intermetallic compounds were formed in the interface of the optimum joint where the tensile failure was observed to take place.

  4. NDT studies of laser cladding defects of pure copper on SS316L for in vessel materials for fusion reactor applications

    International Nuclear Information System (INIS)

    Shaikh, S.; Buddu, Ramesh Kumar; Raole, P.M.; Sarkar, B.

    2015-01-01

    The pure thick copper coatings of 1-3 mm are required for the in-vessel materials for the plasma facing components in fusion reactor systems to extract the very high heat flux in shorter durations (like VDEs) and to protect the in vessel components. Laser cladding technique is one of the potential technique for thick coatings on substrate materials. The present study reports the NDT characterization studies carried on samples of pure copper powder cladded on SS316L substrates of thickness 1 mm - 3 mm , fabricated by CO_2 laser system. Process parameters optimization like laser power, laser travel speed, spot size, powder feed rate and shield gas flow show the effect on quality of final cladding on steel substrates. X-ray radiography and Ultrasonic testing has been carried out thoroughly on the fabricated samples and defects are analyzed. Ultrasonic scan tests using different probes are employed as the interface defects are not thoroughly revealed by radiography. The calibration has been carried out by the test sample plate with known defect size created and various process parameters like amplitude, gain and metal velocity, relevant to specimen are chosen for probes calibration. The interface defects of porosity, lack of penetration, cracks or group porosities are observed in few set of samples developed. Radiography examination revealed the porosity at extreme edges and distributed porosity in the middle for thick cladding. Ultrasonic manual A-scanning with TR probe provides qualitative information about flaw and broadly gives its location of the defects. Samples of 1 mm thick cladding have shown relatively less porosity defects at the interface compared to 3 mm thick samples. (author)

  5. Cohomology in the Pure Spinor Formalism for the Superstring

    International Nuclear Information System (INIS)

    Berkovits, Nathan

    2000-01-01

    A manifestly super-Poincare covariant formalism for the superstring has recently been constructed using a pure spinor variable. Unlike the covariant Green-Schwarz formalism, this new formalism is easily quantized with a BRST operator and tree-level scattering amplitudes have been evaluated in a manifestly covariant manner. In this paper, the cohomology of the BRST operator in the pure spinor formalism is shown to give the usual light-cone Green-Schwarz spectrum. Although the BRST operator does not directly involve the Virasoro constraint, this constraint emerges after expressing the pure spinor variable in terms of SO(8) variables. (author)

  6. Shunting arc plasma source for pure carbon ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y. [Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

    2012-02-15

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm{sup 2} at the peak of the pulse.

  7. Shunting arc plasma source for pure carbon ion beam.

    Science.gov (United States)

    Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA∕mm(2) at the peak of the pulse.

  8. Corrosion of pure OFHC-copper in simulated repository conditions

    International Nuclear Information System (INIS)

    Aaltonen, P.

    1990-04-01

    The research program 'Corrosion of pure OFHC-copper in simulated repository conditions' was planned to provide an experimental evaluation with respect to the theoretical calculations and forecasts made for the corrosion behaviour of pure copper in bentonite groundwater environments at temperatures between 20-80 deg C. The aim of this study in the first place is to evaluate the effects of groundwater composition, bentonite and temperature on the equilibrium and possible corrosion reactions between pure copper and the simulated repository environment. The progress report includes the results obtained after 36 months exposure time

  9. DEVELOPMENT OF VEGETABLE PUREES AND DRINKS BY LACTIC ACID FERMENTATION

    Directory of Open Access Journals (Sweden)

    At. Kraevska

    2014-03-01

    Full Text Available The object of this work was to investigate the possibility for development of vegetable purees and drinks by lactic acid fermentation. It was found that by the direct lactic acid fermentation of Lb.plantarum strain 226/1 the vitamin composition of vegetable purees is preserved and the biological value is increased. Drinks, prepared from fermented vegetable purees were remarkable with the pleasant lactic acid taste, the sucrose-acid composition was stable and balanced and they can be used both in the rational and in the dietary nutrition.

  10. Preserving Ultra-Pure Uranium-233

    International Nuclear Information System (INIS)

    Krichinsky, Alan M.; Goldberg, Steven A.; Hutcheon, Ian D.

    2011-01-01

    Uranium-233 ( 233 U) is a synthetic isotope of uranium formed under reactor conditions during neutron capture by natural thorium ( 232 Th). At high purities, this synthetic isotope serves as a crucial reference material for accurately quantifying and characterizing uranium-bearing materials assays and isotopic distributions for domestic and international nuclear safeguards. Separated, high purity 233 U is stored in vaults at Oak Ridge National Laboratory (ORNL). These materials represent a broad spectrum of 233 U from the standpoint of isotopic purity - the purest being crucial for precise analyses in safeguarding uranium. All 233 U at ORNL is currently scheduled to be disposed of by down-blending with depleted uranium beginning in 2015. This will reduce safety concerns and security costs associated with storage. Down-blending this material will permanently destroy its potential value as a certified reference material for use in uranium analyses. Furthermore, no credible options exist for replacing 233 U due to the lack of operating production capability and the high cost of restarting currently shut down capabilities. A study was commissioned to determine the need for preserving high-purity 233 U. This study looked at the current supply and the historical and continuing domestic need for this crucial isotope. It examined the gap in supplies and uses to meet domestic needs and extrapolated them in the context of international safeguards and security activities - superimposed on the recognition that existing supplies are being depleted while candidate replacement material is being prepared for disposal. This study found that the total worldwide need by this projection is at least 850 g of certified 233 U reference material over the next 50 years. This amount also includes a strategic reserve. To meet this need, 18 individual items totaling 959 g of 233 U were identified as candidates for establishing a lasting supply of certified reference materials (CRM), all

  11. De-trending of wind speed variance based on first-order and second-order statistical moments only

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Hansen, Kurt Schaldemose

    2014-01-01

    The lack of efficient methods for de-trending of wind speed resource data may lead to erroneous wind turbine fatigue and ultimate load predictions. The present paper presents two models, which quantify the effect of an assumed linear trend on wind speed standard deviations as based on available...... statistical data only. The first model is a pure time series analysis approach, which quantifies the effect of non-stationary characteristics of ensemble mean wind speeds on the estimated wind speed standard deviations as based on mean wind speed statistics only. This model is applicable to statistics...... of arbitrary types of time series. The second model uses the full set of information and includes thus additionally observed wind speed standard deviations to estimate the effect of ensemble mean non-stationarities on wind speed standard deviations. This model takes advantage of a simple physical relationship...

  12. Design of very high speed electric generators

    International Nuclear Information System (INIS)

    Labollita, Santiago

    2008-01-01

    This work approaches the design process of an electric generator suitable for running efficiently at high speed, driven by a turbo shaft.The axial flux concept was used.For the mechanical design of the prototype, cooling capacity and mounting method were considered, looking for simplicity of the parts evolved. Neodymium-iron-boron permanent magnets were used as magnetic source.For the electrical design, a calculation tool was developed in order to predict the prototype electrical parameters and optimize its geometry.The goal was to obtain 1 kW of electric power at a speed of 100,000 rpm.The efficiency and electrical behaviour of the prototype were characterized at speeds between 2,000 rpm and 30,000 rpm and then the behaviour at the design condition was predicted by obtaining an equivalent electric circuit.The estimated load voltage was 237 V as well as an electrical efficiency of 95%.Eddy current effects were not recognized. Increase of the internal resistance and decree of inductance were observed while raising the electric frequency.Finally, an electronic system was developed in order to use the prototype as a c.c. motor. Global performance was measured according to different supply characteristic. An optimum supply voltage was found.A maximum efficiency of 63% was reached. [es

  13. SEAL FOR HIGH SPEED CENTRIFUGE

    Science.gov (United States)

    Skarstrom, C.W.

    1957-12-17

    A seal is described for a high speed centrifuge wherein the centrifugal force of rotation acts on the gasket to form a tight seal. The cylindrical rotating bowl of the centrifuge contains a closure member resting on a shoulder in the bowl wall having a lower surface containing bands of gasket material, parallel and adjacent to the cylinder wall. As the centrifuge speed increases, centrifugal force acts on the bands of gasket material forcing them in to a sealing contact against the cylinder wall. This arrangememt forms a simple and effective seal for high speed centrifuges, replacing more costly methods such as welding a closure in place.

  14. Nanocrystalline Ni-Co Alloy Synthesis by High Speed Electrodeposition

    Directory of Open Access Journals (Sweden)

    Jamaliah Idris

    2013-01-01

    Full Text Available Electrodeposition of nanocrystals is economically and technologically viable production path for the synthesis of pure metals and alloys both in coatings and bulk form. The study presents nanocrystalline Ni-Co alloy synthesis by high speed electrodeposition. Nanocrystalline Ni-Co alloys coatings were prepared by direct current (DC and deposited directly on steel and aluminum substrates without any pretreatment, using high speed electrodeposition method. The influence of the electrolysis parameters, such as cathodic current density and temperature at constant pH, on electrodeposition and microstructure of Ni-Co alloys were examined. A homogeneous surface morphology was obtained at all current densities of the plated samples, and it was evident that the current density and temperature affect the coating thickness of Ni-Co alloy coatings.

  15. Electrorefining of High Carbon Ferromanganese in Molten Salts to Produce Pure Ferromanganese

    Directory of Open Access Journals (Sweden)

    Xiao S. J.

    2017-09-01

    Full Text Available High carbon ferromanganese is used as a starting material to prepare pure ferromanganese by electrorefining in molten salts. High carbon ferromanganese was applied as the anode, molybdenum was the cathode and Ag/AgCl was the reference electrode. The anodic dissolution was investigated by linear polarization in molten NaCl-KCl system. Then potentiostatic electrolysis was carried out to produce pure ferromanganese from high carbon ferromanganese. The cathodic product was determined to be a mixture of manganese and iron by x-ray diffraction (XRD. The content of carbon in the product was analyzed by carbon and sulfur analyzer. The post-electrolysis anode was characterized by scanning electron microscope (SEM. The mechanism of the anode dissolution and the distribution of the main impurity of carbon and silicon after electrolysis were discussed.

  16. Studies on various properties of pure and Li-doped Barium Hydrogen Phosphate (BHP) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Nallamuthu, D. [Department of Physics, Aditanar College of Arts and Science, Tiruchendur 628216, Tamil Nadu (India); Selvarajan, P., E-mail: pselvarajanphy@yahoo.co.i [Department of Physics, Aditanar College of Arts and Science, Tiruchendur 628216, Tamil Nadu (India); Freeda, T.H. [Physics Research Centre, S.T. Hindu College, Nagercoil 629002 (India)

    2010-12-15

    Single crystals of pure and Li-doped barium hydrogen phosphate (BHP) were grown by solution method with gel technique. Various properties of the harvested crystals were studied by carrying out single crystal and powder XRD, FTIR, TG/DTA, microhardness and dielectric studies. Atomic absorption study was carried out for Li-doped BHP crystal to check the presence of Li dopants. Unit cell dimensions and diffracting planes of the grown crystals have been identified from XRD studies. Functional groups of the title compounds have been identified from FTIR studies. Density of the grown crystals was calculated using the XRD data. Thermal stability of the samples was checked by TG/DTA studies. Mechanical and dielectric characterizations of the harvested pure and Li-doped BHP crystals reveal the mechanical strength and ferroelectric transition. The observed results are reported and discussed.

  17. The effect of pure state structure on nonequilibrium dynamics

    International Nuclear Information System (INIS)

    Newman, C M; Stein, D L

    2008-01-01

    Motivated by short-range Ising spin glasses, we review some rigorous results and their consequences for the relation between the number/nature of equilibrium pure states and nonequilibrium dynamics. Two of the consequences for spin glass dynamics following an instantaneous deep quench to a temperature with broken spin flip symmetry are: (1) almost all initial configurations lie on the boundary between the basins of attraction of multiple pure states; (2) unless there are uncountably many pure states with almost all pairs having zero overlap, there can be no equilibration to a pure state as time t → ∞. We discuss the relevance of these results to the difficulty of equilibration of spin glasses. We also review some results concerning the 'nature versus nurture' problem of whether the large-t behavior of both ferromagnets and spin glasses following a deep quench is determined more by the initial configuration (nature) or by the dynamics realization (nurture)

  18. Passage from a pure state description to the microcanonical ...

    Indian Academy of Sciences (India)

    ensemble distribution (microcanonical distribution) has no memory of the initial state. In .... state is not erased as the subspace is still state-dependent and no statistical mechanics ... using in the present context, even for pure states, the entropy.

  19. Computer Solution to the Game of Pure Strategy

    Directory of Open Access Journals (Sweden)

    Laurent Bartholdi

    2012-11-01

    Full Text Available We numerically solve the classical "Game of Pure Strategy" using linear programming. We notice an intricate even-odd behaviour in the results of our computations that seems to encourage odd or maximal bids.

  20. Bayero Journal of Pure and Applied Sciences: Submissions

    African Journals Online (AJOL)

    Bayero Journal of Pure and Applied Sciences (BAJOPAS) is an international journal that publishes original research and critical reviews in broad areas of ... Technology, Mathematical Sciences, Microbiology, Physics and Medical Sciences.

  1. A novel application of Recursive Equation Method for determining thermodynamic properties of single phase fluids from density and speed-of-sound measurements

    International Nuclear Information System (INIS)

    Lago, S.; Giuliano Albo, P.A.

    2013-01-01

    Highlights: ► A novel method for calculating the isobaric specific heat capacity is presented. ► Heat capacity (C p ) was determined only by speed-of-sound and density measurements. ► (C p ) temperature dependence has been related to speed-of-sound by a new expression. ► Heat capacity for water, nonane, undecane, and rapeseed oil methyl ester are obtained. -- Abstract: The determination of thermal quantities from mechanical properties is still a challenge in the thermodynamic field. In this work, the authors suggest a preliminary numerical calculation which allows to determine the constant pressure specific heat capacity, starting from density and speed-of-sound experimental values, as input data. This method is a variant of the well characterized Recursive Equation Method (REM) [1] and permits to develop empirical equations of state for single phase fluids. In particular, the isobaric specific heat capacity has been obtained, in a wide range of temperatures and pressures, for pure water, n-nonane, n-undecane, and rapeseed oil methyl ester. The results have been compared with those available in the literature, when it was possible. Moreover, the typical uncertainty of heat capacity has been estimated to be in the order of 1.5%; however it has been shown that it can be improved when proper distributions of the experimental points are available

  2. General entanglement-assisted transformation for bipartite pure quantum states

    Science.gov (United States)

    Song, Wei; Huang, Yan; Nai-LeLiu; Chen, Zeng-Bing

    2007-01-01

    We introduce the general catalysts for pure entanglement transformations under local operations and classical communications in such a way that we disregard the profit and loss of entanglement of the catalysts per se. As such, the possibilities of pure entanglement transformations are greatly expanded. We also design an efficient algorithm to detect whether a k × k general catalyst exists for a given entanglement transformation. This algorithm can also be exploited to witness the existence of standard catalysts.

  3. The b ghost of the pure spinor formalism is nilpotent

    Energy Technology Data Exchange (ETDEWEB)

    Chandia, Osvaldo, E-mail: osvaldo.chandia@uai.c [Departamento de Ciencias, Facultad de Artes Liberales and Facultad de Ingenieria y Ciencias, Universidad Adolfo Ibanez, Santiago (Chile)

    2011-01-10

    The ghost for world-sheet reparametrization invariance is not a fundamental field in the pure spinor formalism. It is written as a combination of pure spinor variables which have conformal dimension two and such that it commutes with the BRST operator to give the world-sheet stress tensor. We show that the ghost variable defined in this way is nilpotent since the OPE of b with itself does not have singularities.

  4. Type I supergravity effective action from pure spinor formalism

    International Nuclear Information System (INIS)

    Alencar, Geova

    2009-01-01

    Using the pure spinor formalism, we compute the tree-level correlation functions for three strings, one closed and two open, in N = 1 D = 10 superspace. Expanding the superfields in components, the respective terms of the effective action for the type I supergravity are obtained. All terms found agree with the effective action known in the literature. This result gives one more consistency test for the pure spinor formalism.

  5. Guidelines for setting speed limits

    CSIR Research Space (South Africa)

    Wium, DJW

    1986-02-01

    Full Text Available , parking and loading manoeuvres, access to bounding properties, intersections, width of road without central median and clear roadside area. The method should result in greater uniformity in speed limits for similar circumstances as set by different...

  6. Testing effects in mixed- versus pure-list designs.

    Science.gov (United States)

    Rowland, Christopher A; Littrell-Baez, Megan K; Sensenig, Amanda E; DeLosh, Edward L

    2014-08-01

    In the present study, we investigated the role of list composition in the testing effect. Across three experiments, participants learned items through study and initial testing or study and restudy. List composition was manipulated, such that tested and restudied items appeared either intermixed in the same lists (mixed lists) or in separate lists (pure lists). In Experiment 1, half of the participants received mixed lists and half received pure lists. In Experiment 2, all participants were given both mixed and pure lists. Experiment 3 followed Erlebacher's (Psychological Bulletin, 84, 212-219, 1977) method, such that mixed lists, pure tested lists, and pure restudied lists were given to independent groups. Across all three experiments, the final recall results revealed significant testing effects for both mixed and pure lists, with no reliable difference in the magnitude of the testing advantage across list designs. This finding suggests that the testing effect is not subject to a key boundary condition-list design-that impacts other memory phenomena, including the generation effect.

  7. Speed management : enforcement and new technologies.

    NARCIS (Netherlands)

    Wegman, F.C.M. & Goldenbeld, C.

    2006-01-01

    Due to the massive character of speeding and inappropriate travel speeds, speed management continues to be an important and challenging policy area. Estimates are that in about a quarter to one third of fatal crashes excessive speeds are involved, making speed one of the crucial factors in road

  8. Speed Variance and Its Influence on Accidents.

    Science.gov (United States)

    Garber, Nicholas J.; Gadirau, Ravi

    A study was conducted to investigate the traffic engineering factors that influence speed variance and to determine to what extent speed variance affects accident rates. Detailed analyses were carried out to relate speed variance with posted speed limit, design speeds, and other traffic variables. The major factor identified was the difference…

  9. Characterization of the voltage control systems and speed of a synchronous machine of high power for short circuit testing; Caracterizacion de los sistemas de control de voltaje y velocidad de una maquina sincrona de alta potencia para pruebas de corto circuito

    Energy Technology Data Exchange (ETDEWEB)

    Segura Ozuna, Victor Octavio; Hernandez Rodriguez, Isaura Victoria; Alcaide Godinez, Indira Xochiquetzal; Garduno Ramirez, Raul; Montero Cervantes, Julio Cesar [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Ruiz Rodriguez, Genaro; Martinez Torres; Ricardo [CFE-LAPEM, Irapuato, Guanajuato (Mexico)

    2012-07-01

    This paper introduces a characterization of the behavior of the speed and voltage control systems of a special purpose synchronous machine (GCC) based on measuring and monitoring physical signals, and recording of the sampled waveforms. Basically, the GCC supplies the energy to perform high-power short-circuits tests to certify electrical equipment and components, as required by the Comision Federal de Electricidad (CFE) in Mexico. The GCC operates alternately as motor and generator. With the GCC operating as motor, speed control during startup, acceleration, re-acceleration and braking is carried out by a static frequency converter (SFC). Complementary, the voltage controller manipulates excitation power to control terminal voltage when the GCC operates as generator and regulates excitation current when the GCC operates as motor. Compared to conventional voltage regulation systems, which must go off in case of short-circuit, the GCC voltage regulator must keep controlling field excitation to maintain the required line current and terminal voltage during short-circuit tests. Monitoring of physical signals was carried out with a portable data acquisition system based on SCXI and PXI digital platforms. A total of 78 signals were monitored with a 6 kHz sampling rate that was enough to obtain detailed signal waveforms. Data captured was processed and plotted for analysis. The signal graphs show the current real behavior of both, the voltage control system and the speed control system, and constitute a precise characterization of their behavior. [Spanish] Este documento presenta una caracterizacion del comportamiento de los sistemas de control de velocidad y voltaje de una maquina sincrona de proposito especial (GCC) basada en la medicion y monitoreo de senales fisicas, asi como en el registro de las formas de onda muestreadas. Basicamente, la GCC suministra la energia para efectuar pruebas de corto circuito de alta potencia para certificar equipo y componentes

  10. Spatial and temporal patterns of global onshore wind speed distribution

    International Nuclear Information System (INIS)

    Zhou, Yuyu; Smith, Steven J

    2013-01-01

    Wind power, a renewable energy source, can play an important role in electrical energy generation. Information regarding wind energy potential is important both for energy related modeling and for decision-making in the policy community. While wind speed datasets with high spatial and temporal resolution are often ultimately used for detailed planning, simpler assumptions are often used in analysis work. An accurate representation of the wind speed frequency distribution is needed in order to properly characterize wind energy potential. Using a power density method, this study estimated global variation in wind parameters as fitted to a Weibull density function using NCEP/climate forecast system reanalysis (CFSR) data over land areas. The Weibull distribution performs well in fitting the time series wind speed data at most locations according to R 2 , root mean square error, and power density error. The wind speed frequency distribution, as represented by the Weibull k parameter, exhibits a large amount of spatial variation, a regionally varying amount of seasonal variation, and relatively low decadal variation. We also analyzed the potential error in wind power estimation when a commonly assumed Rayleigh distribution (Weibull k = 2) is used. We find that the assumption of the same Weibull parameter across large regions can result in non-negligible errors. While large-scale wind speed data are often presented in the form of mean wind speeds, these results highlight the need to also provide information on the wind speed frequency distribution. (letter)

  11. Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp

    DEFF Research Database (Denmark)

    Bell, Ian H.; Wronski, Jorrit; Quoilin, Sylvain

    2014-01-01

    property correlations described here have been implemented into CoolProp, an open-source thermophysical property library. This library is written in C++, with wrappers available for the majority of programming languages and platforms of technical interest. As of publication, 110 pure and pseudo-pure fluids...... are included in the library, as well as properties of 40 incompressible fluids and humid air. The source code for the CoolProp library is included as an electronic annex....

  12. An equation of state for purely kinetic k-essence inspired by cosmic topological defects

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, Ruben; Gonzalez, Eduardo L.; Queijeiro, Alfonso [Instituto Politecnico Nacional, Departamento de Fisica, Escuela Superior de Fisica y Matematicas, Ciudad de Mexico (Mexico)

    2017-06-15

    We investigate the physical properties of a purely kinetic k-essence model with an equation of state motivated in superconducting membranes. We compute the equation of state parameter w and discuss its physical evolution via a nonlinear equation of state. Using the adiabatic speed of sound and energy density, we restrict the range of parameters of the model in order to have an acceptable physical behavior. We study the evolution of the scale factor and address the question of the possible existence of finite-time future singularities. Furthermore, we analyze the evolution of the luminosity distance d{sub L} with redshift z by comparing (normalizing) it with the ΛCDM model. Since the equation of state parameter is z-dependent the evolution of the luminosity distance is also analyzed using the Alcock-Paczynski test. (orig.)

  13. Numerical Simulation and Experimental Analysis of The Equal Channel Angular Pressing of Pure Titanium

    Energy Technology Data Exchange (ETDEWEB)

    Quang, Pham; Nghiep, Do Minh [Hanoi University of Science and Technology, Hanoi (Viet Nam)

    2016-03-15

    The plastic deformation behavior of pure Ti during equal channel angular pressing (ECAP) is simulated using the three-dimension finite volume method and is experimentally investigated. The calculated effective strain and effective stress distributions and histories are analyzed to understand the local and global deformation characteristics. The predicted plastic deformation behavior of the Ti workpiece during the ECAP process was compared with the theoretical total strain for every pass at RAM speed v of 10 mm/s and at constant temperature of 400 ℃. The simulated strain and stress distributions are homogenous in the central region of the ECAP processed Ti. The experimental ECAP performed with four, eight, and twelve passes at 400 ℃ results in refined grain sizes of approximately 5-10 µm, 0.4⁓0.5 µm and 0.1⁓0.2 µm, respectively.

  14. Low speed phaselock speed control system. [for brushless dc motor

    Science.gov (United States)

    Fulcher, R. W.; Sudey, J. (Inventor)

    1975-01-01

    A motor speed control system for an electronically commutated brushless dc motor is provided which includes a phaselock loop with bidirectional torque control for locking the frequency output of a high density encoder, responsive to actual speed conditions, to a reference frequency signal, corresponding to the desired speed. The system includes a phase comparator, which produces an output in accordance with the difference in phase between the reference and encoder frequency signals, and an integrator-digital-to-analog converter unit, which converts the comparator output into an analog error signal voltage. Compensation circuitry, including a biasing means, is provided to convert the analog error signal voltage to a bidirectional error signal voltage which is utilized by an absolute value amplifier, rotational decoder, power amplifier-commutators, and an arrangement of commutation circuitry.

  15. Neural correlates of the difference between working memory speed and simple sensorimotor speed: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Hikaru Takeuchi

    Full Text Available The difference between the speed of simple cognitive processes and the speed of complex cognitive processes has various psychological correlates. However, the neural correlates of this difference have not yet been investigated. In this study, we focused on working memory (WM for typical complex cognitive processes. Functional magnetic resonance imaging data were acquired during the performance of an N-back task, which is a measure of WM for typical complex cognitive processes. In our N-back task, task speed and memory load were varied to identify the neural correlates responsible for the difference between the speed of simple cognitive processes (estimated from the 0-back task and the speed of WM. Our findings showed that this difference was characterized by the increased activation in the right dorsolateral prefrontal cortex (DLPFC and the increased functional interaction between the right DLPFC and right superior parietal lobe. Furthermore, the local gray matter volume of the right DLPFC was correlated with participants' accuracy during fast WM tasks, which in turn correlated with a psychometric measure of participants' intelligence. Our findings indicate that the right DLPFC and its related network are responsible for the execution of the fast cognitive processes involved in WM. Identified neural bases may underlie the psychometric differences between the speed with which subjects perform simple cognitive tasks and the speed with which subjects perform more complex cognitive tasks, and explain the previous traditional psychological findings.

  16. System analysis of automated speed enforcement implementation.

    Science.gov (United States)

    2016-04-01

    Speeding is a major factor in a large proportion of traffic crashes, injuries, and fatalities in the United States. Automated Speed Enforcement (ASE) is one of many approaches shown to be effective in reducing speeding violations and crashes. However...

  17. Influence of Scanning Speed on the Microhardness Property of ...

    African Journals Online (AJOL)

    Akorede

    KEYWORDS: Additive Manufacturing, Laser Metal Deposition, Microstructural Characterization, Scanning speed, Titanium. Alloy. [Received August 31 2016; Revised December 13 2016; Accepted December 20 2016]. I. INTRODUCTION. Titanium and its alloys exhibit a very special combination of properties and corrosion ...

  18. High speed electro optic polymer micro-ringresonator

    NARCIS (Netherlands)

    Leinse, Arne; Diemeer, Mart; Driessen, A.

    2004-01-01

    An electro-optic polymer micro-ring resonator for high speed modulation was designed, realized and characterized. The design of layer-stack and electrodes was done such that modulation frequencies up till 1 GHz should be possible. The device consists of a ridge waveguide, defined in a negative

  19. Spatial layout affects speed discrimination

    Science.gov (United States)

    Verghese, P.; Stone, L. S.

    1997-01-01

    We address a surprising result in a previous study of speed discrimination with multiple moving gratings: discrimination thresholds decreased when the number of stimuli was increased, but remained unchanged when the area of a single stimulus was increased [Verghese & Stone (1995). Vision Research, 35, 2811-2823]. In this study, we manipulated the spatial- and phase relationship between multiple grating patches to determine their effect on speed discrimination thresholds. In a fusion experiment, we merged multiple stimulus patches, in stages, into a single patch. Thresholds increased as the patches were brought closer and their phase relationship was adjusted to be consistent with a single patch. Thresholds increased further still as these patches were fused into a single patch. In a fission experiment, we divided a single large patch into multiple patches by superimposing a cross with luminance equal to that of the background. Thresholds decreased as the large patch was divided into quadrants and decreased further as the quadrants were maximally separated. However, when the cross luminance was darker than the background, it was perceived as an occluder and thresholds, on average, were unchanged from that for the single large patch. A control experiment shows that the observed trend in discrimination thresholds is not due to the differences in perceived speed of the stimuli. These results suggest that the parsing of the visual image into entities affects the combination of speed information across space, and that each discrete entity effectively provides a single independent estimate of speed.

  20. Generalized Geometric Quantum Speed Limits

    Directory of Open Access Journals (Sweden)

    Diego Paiva Pires

    2016-06-01

    Full Text Available The attempt to gain a theoretical understanding of the concept of time in quantum mechanics has triggered significant progress towards the search for faster and more efficient quantum technologies. One of such advances consists in the interpretation of the time-energy uncertainty relations as lower bounds for the minimal evolution time between two distinguishable states of a quantum system, also known as quantum speed limits. We investigate how the nonuniqueness of a bona fide measure of distinguishability defined on the quantum-state space affects the quantum speed limits and can be exploited in order to derive improved bounds. Specifically, we establish an infinite family of quantum speed limits valid for unitary and nonunitary evolutions, based on an elegant information geometric formalism. Our work unifies and generalizes existing results on quantum speed limits and provides instances of novel bounds that are tighter than any established one based on the conventional quantum Fisher information. We illustrate our findings with relevant examples, demonstrating the importance of choosing different information metrics for open system dynamics, as well as clarifying the roles of classical populations versus quantum coherences, in the determination and saturation of the speed limits. Our results can find applications in the optimization and control of quantum technologies such as quantum computation and metrology, and might provide new insights in fundamental investigations of quantum thermodynamics.

  1. Dazzle camouflage affects speed perception.

    Directory of Open Access Journals (Sweden)

    Nicholas E Scott-Samuel

    Full Text Available Movement is the enemy of camouflage: most attempts at concealment are disrupted by motion of the target. Faced with this problem, navies in both World Wars in the twentieth century painted their warships with high contrast geometric patterns: so-called "dazzle camouflage". Rather than attempting to hide individual units, it was claimed that this patterning would disrupt the perception of their range, heading, size, shape and speed, and hence reduce losses from, in particular, torpedo attacks by submarines. Similar arguments had been advanced earlier for biological camouflage. Whilst there are good reasons to believe that most of these perceptual distortions may have occurred, there is no evidence for the last claim: changing perceived speed. Here we show that dazzle patterns can distort speed perception, and that this effect is greatest at high speeds. The effect should obtain in predators launching ballistic attacks against rapidly moving prey, or modern, low-tech battlefields where handheld weapons are fired from short ranges against moving vehicles. In the latter case, we demonstrate that in a typical situation involving an RPG7 attack on a Land Rover the reduction in perceived speed is sufficient to make the grenade miss where it was aimed by about a metre, which could be the difference between survival or not for the occupants of the vehicle.

  2. Gate-Driven Pure Spin Current in Graphene

    Science.gov (United States)

    Lin, Xiaoyang; Su, Li; Si, Zhizhong; Zhang, Youguang; Bournel, Arnaud; Zhang, Yue; Klein, Jacques-Olivier; Fert, Albert; Zhao, Weisheng

    2017-09-01

    The manipulation of spin current is a promising solution for low-power devices beyond CMOS. However, conventional methods, such as spin-transfer torque or spin-orbit torque for magnetic tunnel junctions, suffer from large power consumption due to frequent spin-charge conversions. An important challenge is, thus, to realize long-distance transport of pure spin current, together with efficient manipulation. Here, the mechanism of gate-driven pure spin current in graphene is presented. Such a mechanism relies on the electrical gating of carrier-density-dependent conductivity and spin-diffusion length in graphene. The gate-driven feature is adopted to realize the pure spin-current demultiplexing operation, which enables gate-controllable distribution of the pure spin current into graphene branches. Compared with the Elliott-Yafet spin-relaxation mechanism, the D'yakonov-Perel spin-relaxation mechanism results in more appreciable demultiplexing performance. The feature of the pure spin-current demultiplexing operation will allow a number of logic functions to be cascaded without spin-charge conversions and open a route for future ultra-low-power devices.

  3. Corrosion of pure magnesium under thin electrolyte layers

    International Nuclear Information System (INIS)

    Zhang Tao; Chen Chongmu; Shao Yawei; Meng Guozhe; Wang Fuhui; Li Xiaogang; Dong Chaofang

    2008-01-01

    The corrosion behavior of pure magnesium was investigated by means of cathodic polarization curve, electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) under aerated and deaerated thin electrolyte layers (TEL) with various thicknesses. Based on shot noise theory and stochastic theory, the EN results were quantitatively analyzed by using the Weibull and Gumbel distribution function, respectively. The results show that the cathodic process of pure magnesium under thin electrolyte layer was dominated by hydrogen reduction. With the decreasing of thin electrolyte layer thickness, cathodic process was retarded slightly while the anodic process was inhibited significantly, which indicated that both the cathodic and anodic process were inhibited in the presence of oxygen. The absence of oxygen decreased the corrosion resistance of pure magnesium in case of thin electrolyte layer. The corrosion was more localized under thin electrolyte layer than that in bulk solution. The results also demonstrate that there exist two kinds of effects for thin electrolyte layer on the corrosion behavior of pure magnesium: (1) the rate of pit initiation was evidently retarded compared to that in bulk solution; (2) the probability of pit growth oppositely increased. The corrosion model of pure magnesium under thin electrolyte layer was suggested in the paper

  4. Entropy balance in pure interactions of open quantum systems

    International Nuclear Information System (INIS)

    Urigu, R.

    1989-01-01

    Processes are considered in which a statistical ensemble w of quantum systems is split into ensembles, or channels (w i ), conditional to the occurrence, with respective probabilities (p i w ), of associated macroscopic effects. These processes are described here by a family of operations T i : w → p i w w iT , which remarkably generalize the usual state reductions of the nondestructive measurements. In a previous work it was proved that the microscopic entropy of the given open system decreases or at most remains constant if all the T i are pure operations, i.e., they transform pure states into pure states; it is proved here that the increase in entropy of the external world, computed as S Tm (w) = - Σ i p i w lg p i w , is sufficient to compensate for such an entropy decrease whenever the T i are all pure operations of the first kind, whereas whenever some T i is pure of the second kind (or nonpure, too), the total entropy, computed as above, may decrease

  5. Advancing electric-vehicle development with pure-lead-tin battery technology

    Science.gov (United States)

    O'Brien, W. A.; Stickel, R. B.; May, G. J.

    Electric-vehicle (EV) development continues to make solid progress towards extending vehicle range, reliability and ease of use, aided significantly by technological advances in vehicle systems. There is, however, a widespread misconception that current battery technologies are not capable of meeting even the minimum user requirements that would launch EVs into daily use. Existing pure-lead-tin technology is moving EVs out of research laboratories and onto the streets, in daily side-by-side operation with vehicles powered by conventional gasoline and alternative fuels. This commercially available battery technology can provide traffic-compatible performance in a reliable and affordable manner, and can be used for either pure EVs or hybrid electric vehicles (HEVs). Independent results obtained when applying lead-tin batteries in highly abusive conditions, both electrically and environmentally, are presented. The test fleet of EVs is owned and operated by Arizona Public Service (APS), an electric utility in Phoenix, AZ, USA. System, charger and battery development will be described. This gives a single charge range of up to 184 km at a constant speed of 72 km h -1, and with suitable opportunity charging, a 320 km range in a normal 8 h working day.

  6. Variable Speed Rotor System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Variable speed rotors will give helicopters several advantages: higher top speed, greater fuel efficiency, momentary emergency over-power, resonance detuning...

  7. Medulloblastoma Presenting With Pure Word Deafness: Report of One Case and Review of Literature

    Directory of Open Access Journals (Sweden)

    Yen-Ting Chou

    2011-10-01

    Full Text Available Pure word deafness (PWD is a rare disorder characterized by impaired verbal comprehension sparing discrimination and recognition of nonverbal sounds with relatively normal spontaneous speech, writing, and reading comprehension. Etiologies of this syndrome are varied, and there are rare reports about brain tumor with PWD in children. We report a case of medulloblastoma presented with PWD in a 7-year-old girl. She visited our outpatient clinic because of English dictation performance deterioration. PWD was diagnosed by the otolaryngologist after examinations. Posterior fossa tumor and obstructive hydrocephalus were shown in the magnetic resonance imaging of the brain. The diagnosis of medulloblastoma was then made by pathology.

  8. Anodic oxidation of commercially pure titanium for purification of polluted water

    Science.gov (United States)

    Benkafada, Faouzia; Kerdoud, Djahida; Bouchoucha, Ali

    2018-05-01

    Anodisation of pure titanium has been carried out in sulphuric acid solution at potentials ranging from 40 V to 5 days. We studied the parameters influencing the anodic deposition such as acid concentration and anodic periods. Anodic oxides thin films were characterized by X-ray diffraction, cyclic polarization and electrochemical impedance spectroscopy. The I-V curves and electrochemical impedance measurements were carried out in 0.1 N NaOH solution. The results indicated that although the thin films obtained by anodic oxidation are nonstoichiometric, they have an electric behaviour like n-type semiconducting material.

  9. Evolution of cleared channels in neutron-irradiated pure copper as a function of tensile strain

    DEFF Research Database (Denmark)

    Edwards, D.J.; Singh, B.N.

    2004-01-01

    Tensile specimens of pure copper were neutron irradiated at similar to323 K to a displacement dose of 0.3 dpa (displacement per atom). Five irradiated specimens were tensile tested at 300 K, but four of the specimens were stopped at specific strains -just before the yield point at similar to90......% of the macroscopic yield, at 1.5% and 5% elongation, and near the ultimate tensile strength at 14.5% elongation, with the 5th specimen tested to failure (e(T) = 22%). SEM and TEM characterization of the deformed specimens revealed that the plastic strain was confined primarily to the 'cleared' channels only...

  10. Rapid hardening induced by electric pulse annealing in nanostructured pure aluminum

    DEFF Research Database (Denmark)

    Zeng, Wei; Shen, Yao; Zhang, Ning

    2012-01-01

    Nanostructured pure aluminum was fabricated by heavy cold-rolling and then subjected to recovery annealing either by applying electric pulse annealing or by traditional air furnace annealing. Both annealing treatments resulted in an increase in yield strength due to the occurrence of a “dislocation...... source-limited hardening” mechanism. However, the hardening kinetics was substantially faster for the electric pulse annealed material. Detailed microstructural characterization suggested that the rapid hardening during electric pulse annealing is related to an enhanced rate of recovery of dislocation...

  11. Dysgerminoma in a case of 46, XY pure gonadal dysgenesis (swyer syndrome: a case report

    Directory of Open Access Journals (Sweden)

    He Anguang

    2011-09-01

    Full Text Available Abstract Simple 46, XY gonadal dysgenesis syndrome, also called Swyer syndrome, is known as pure gonadal dysgenesis. Individuals with the syndrome are characterized by 46, XY karyotype and phenotypically female with female genital appearance, normal Müllerian structures and absent testicular tissue. The condition usually first becomes apparent in adolescence with delayed puberty and primary amenorrhea due to the gonads have no hormonal or reproductive potential. Herein, we report a case of dysgerminoma diagnosed in a dysgenetic gonad of a 21-year-old patient with Swyer syndrome.

  12. Precision measurement of the speed of sound and thermodynamic properties of gases

    International Nuclear Information System (INIS)

    Benedetto, G.; Gavioso, R.M.; Spagnolo, R.

    1999-01-01

    The speed of sound in pure fluids and mixtures is a characteristic and important physical propriety which depends of several intensive thermodynamic variables. This fact indicates that it can be calculated using the appropriate thermodynamic properties of the fluid. Alternatively, experimental evaluation of the speed of sound can be used to determine several fundamental thermophysical properties. Recently, very accurate measurements of the speed of sound in dilute gases have found relevant applications: 1) the last experimental determinations of the value of the universal gas constant R, by measurements in argon, at the triple point of water (1,2); 2) revision of the thermodynamic temperature scales in different temperature ranges (3-5); 3) derivation of the state of many pure gases, which includes methane, helium and ethylene (6-7); 4)determination of the heat capacities and densities of pure gases and mixture (8-16). The aim of this paper is to provide an extensive review of the measurement of the speed of sound in gases and of its theoretical basis, giving prominence to the relevant metrological aspects involved in the determination of this physical quantity

  13. Connections of geometric measure of entanglement of pure symmetric states to quantum state estimation

    International Nuclear Information System (INIS)

    Chen Lin; Zhu Huangjun; Wei, Tzu-Chieh

    2011-01-01

    We study the geometric measure of entanglement (GM) of pure symmetric states related to rank 1 positive-operator-valued measures (POVMs) and establish a general connection with quantum state estimation theory, especially the maximum likelihood principle. Based on this connection, we provide a method for computing the GM of these states and demonstrate its additivity property under certain conditions. In particular, we prove the additivity of the GM of pure symmetric multiqubit states whose Majorana points under Majorana representation are distributed within a half sphere, including all pure symmetric three-qubit states. We then introduce a family of symmetric states that are generated from mutually unbiased bases and derive an analytical formula for their GM. These states include Dicke states as special cases, which have already been realized in experiments. We also derive the GM of symmetric states generated from symmetric informationally complete POVMs (SIC POVMs) and use it to characterize all inequivalent SIC POVMs in three-dimensional Hilbert space that are covariant with respect to the Heisenberg-Weyl group. Finally, we describe an experimental scheme for creating the symmetric multiqubit states studied in this article and a possible scheme for measuring the permanence of the related Gram matrix.

  14. The differences in brain activity between narrow band noise and pure tone tinnitus.

    Directory of Open Access Journals (Sweden)

    Sven Vanneste

    Full Text Available BACKGROUND: Tinnitus is an auditory sensation characterized by the perception of sound or noise in the absence of any external sound source. Based on neurobiological research, it is generally accepted that most forms of tinnitus are attributable to maladaptive plasticity due to damage to auditory system. Changes have been observed in auditory structures such as the inferior colliculus, the thalamus and the auditory cortex as well as in non-auditory brain areas. However, the observed changes show great variability, hence lacking a conclusive picture. One of the reasons might be the selection of inhomogeneous groups in data analysis. METHODOLOGY: The aim of the present study was to delineate the differences between the neural networks involved in narrow band noise and pure tone tinnitus conducting LORETA based source analysis of resting state EEG. CONCLUSIONS: Results demonstrated that narrow band noise tinnitus patients differ from pure tone tinnitus patients in the lateral frontopolar (BA 10, PCC and the parahippocampal area for delta, beta and gamma frequency bands, respectively. The parahippocampal-PCC current density differences might be load dependent, as noise-like tinnitus constitutes multiple frequencies in contrast to pure tone tinnitus. The lateral frontopolar differences might be related to pitch specific memory retrieval.

  15. Erythroblastic Sarcoma Presenting as Bilateral Ovarian Masses in an Infant with Pure Erythroid Leukemia

    Science.gov (United States)

    Wang, Huan-You; Huang, Lily Jun-shen; Garcia, Rolando; Li, Shiyong; Galliani, Carlos A.

    2010-01-01

    Pure erythroid leukemia is a rare subtype of acute erythroid leukemia that is characterized by a predominant erythroid population, and erythroblastic sarcoma has not yet been described in the English literature. Here we report a first case of erythroblastic sarcoma which presented as bilateral ovarian masses in a three and half month old baby girl with pure erythroid leukemia. Bone marrow aspirate and biopsy showed the marrow was completely replaced by large-sized blasts consistent with erythroblasts. Immunophenotypically, both the tumor cells from the ovarian mass and bone marrow blasts were positive for CD117, glycophorin A, and hemoglobin A, demonstrating erythroid differentiation. Reverse transcriptase polymerase chain reaction showed the tumor cells from ovarian mass expressed hemoglobin F and α1 spectrin, confirming their erythroid lineage. Conventional karyotype of the bone marrow aspirates revealed del(6) (q23q25) and trisomy 7 in all 21 cells examined. Fluorescence in situ hybridization of the ovarian mass demonstrated loss of C-MYB at 6q23 locus in 41% of the cells, and deletion of chromosome 7 and 7q in 37% and 66% of cells, respectively. Taken together, we showed, for the first time, that pure erythroid leukemia presented as a myeloid sarcoma in the form of ovarian masses. PMID:21237494

  16. Microstructure and mechanical properties of commercially pure aluminum processed by accumulative back extrusion

    International Nuclear Information System (INIS)

    Haghdadi, N.; Zarei-Hanzaki, A.; Abou-Ras, D.

    2013-01-01

    Accumulative back extrusion (ABE), as a new severe plastic deformation (SPD) method, was applied on a commercially pure aluminum, resulting in an ultrafine microstructure. The grain refinement was attributed to the shearing and/or to the mechanical partitioning of the initial coarse grains as well as different dynamic recrystallization mechanisms (i.e., discontinues and continues ones). The effects of imposing several passes along with the strain reversal path method during consecutive ABE passes were discussed. Mechanical characterization revealed that the yield and ultimate strength of pure Al were significantly increased through applying ABE. This was related to grain boundary and dislocation strengthening, as well as to Orowan dislocation bowing mechanisms. The elongation, however, was deteriorated after ABE processing. This was interpreted through the lack of ability of the material to accommodate the ABE-induced strain, inhomogeneous distribution of strain across the ABE-processed workpieces, and the reduced work hardening capacity of the fine-grained aluminum. The formability index and static toughness were also considered to verify the overall mechanical performance of the ABE-processed pure Al

  17. Structural properties of pure and Fe-doped Yb films prepared by vapor condensation

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Ayala, C., E-mail: chachi@cbpf.br [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180, RJ (Brazil); Facultad de Ciencias Físicas, Universidad Nacional Mayor de San Marcos, Lima, P.O.B. 14-149, Lima 14 (Peru); Passamani, E.C. [Departamento de Física, Universidade Federal do Espírito Santo, Vitória 29075-910, ES (Brazil); Suguihiro, N.M. [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180, RJ (Brazil); Litterst, F.J. [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180, RJ (Brazil); Institut für Physik der Kondensierten Materie, Technische Universität Braunschweig, 38106 Braunschweig (Germany); Baggio Saitovitch, E. [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180, RJ (Brazil)

    2014-10-15

    Ytterbium and iron-doped ytterbium films were prepared by vapor quenching on Kapton substrates at room temperature. Structural characterization was performed by X-ray diffraction and transmission electron microscopy. The aim was to study the microstructure of pure and iron-doped films and thereby to understand the effects induced by iron incorporation. A coexistence of face centered cubic and hexagonal close packed-like structures was observed, the cubic-type structure being the dominant contribution. There is an apparent thickness dependence of the cubic/hexagonal relative ratios in the case of pure ytterbium. Iron-clusters induce a crystalline texture effect, but do not influence the cubic/hexagonal volume fraction. A schematic model is proposed for the microstructure of un-doped and iron-doped films including the cubic- and hexagonal-like structures, as well as the iron distribution in the ytterbium matrix. - Highlights: • Pure and Fe-doped Yb films have been prepared by vapor condensation. • Coexistence of fcc- and hcp-type structures was observed. • No oxide phases have been detected. • Fe-clustering does not affect the fcc/hcp ratio, but favors a crystalline texture. • A schematic model is proposed to describe microscopically the microstructure.

  18. Unified quantum no-go theorems and transforming of quantum pure states in a restricted set

    Science.gov (United States)

    Luo, Ming-Xing; Li, Hui-Ran; Lai, Hong; Wang, Xiaojun

    2017-12-01

    The linear superposition principle in quantum mechanics is essential for several no-go theorems such as the no-cloning theorem, the no-deleting theorem and the no-superposing theorem. In this paper, we investigate general quantum transformations forbidden or permitted by the superposition principle for various goals. First, we prove a no-encoding theorem that forbids linearly superposing of an unknown pure state and a fixed pure state in Hilbert space of a finite dimension. The new theorem is further extended for multiple copies of an unknown state as input states. These generalized results of the no-encoding theorem include the no-cloning theorem, the no-deleting theorem and the no-superposing theorem as special cases. Second, we provide a unified scheme for presenting perfect and imperfect quantum tasks (cloning and deleting) in a one-shot manner. This scheme may lead to fruitful results that are completely characterized with the linear independence of the representative vectors of input pure states. The upper bounds of the efficiency are also proved. Third, we generalize a recent superposing scheme of unknown states with a fixed overlap into new schemes when multiple copies of an unknown state are as input states.

  19. Contributions to the phytocoenologic study in pure european beech stand forests in Codru-Moma Mountains (North-Western Romania

    Directory of Open Access Journals (Sweden)

    Călin-Gheorghe PĂŞCUŢ

    2010-05-01

    Full Text Available In the present work we present a phytocoenologic study on the associations found in pure European beech stand forests in Codru-Moma Mountains namely: Festuco drymejae-Fagetum Morariu et al. 1968, Luzulo albidae-Fagetum sylvaticae Zólyomi 1955.Characterization of the associations we studied and presentation of the tables have been made considering the selection of the most representative relevées of pure European beech forests belonging to Codru-Moma Mountains.The phytocoenoses of pure forest stands of European beech forests belonging to the two associations were analyzed in terms of floristic composition, life forms spectrum, spectrum chart of the floral elements and ecological indices.

  20. High speed laser tomography system

    Science.gov (United States)

    Samsonov, D.; Elsaesser, A.; Edwards, A.; Thomas, H. M.; Morfill, G. E.

    2008-03-01

    A high speed laser tomography system was developed capable of acquiring three-dimensional (3D) images of optically thin clouds of moving micron-sized particles. It operates by parallel-shifting an illuminating laser sheet with a pair of galvanometer-driven mirrors and synchronously recording two-dimensional (2D) images of thin slices of the imaged volume. The maximum scanning speed achieved was 120000slices/s, sequences of 24 volume scans (up to 256 slices each) have been obtained. The 2D slices were stacked to form 3D images of the volume, then the positions of the particles were identified and followed in the consecutive scans. The system was used to image a complex plasma with particles moving at speeds up to cm/s.

  1. Optical, thermal and magnetic studies of pure and cobalt chloride doped L-alanine cadmium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Benila, B.S., E-mail: benjane.benila@gmail.com [Department of Physics and Research Centre, Scott Christian College (Autonomous), Nagercoil 629 003 (India); Bright, K.C. [Department of Physics, St. John' s College, Anchal, Kollam 691 306 (India); Delphine, S. Mary [Department of Physics, Holy Cross College (Autonomous), Nagercoil 629 004 (India); Shabu, R. [Department of Physics and Research Centre, Scott Christian College (Autonomous), Nagercoil 629 003 (India)

    2017-03-15

    Single crystals of L-alanine cadmium chloride (LACC) and cobalt chloride (Co{sup 2+}) doped LACC have been grown by the slow evaporation solution growth technique. The grown crystals were subjected to various characterizations such as powder XRD, SXRD, FTIR, UV–vis, EDAX, TG/DTA, VSM, Dielectric and Second Harmonic Generation (SHG) measurements. The lattice parameters of the grown crystals were determined by single crystal X-ray analysis. EDAX analysis confirms the presence of Co{sup 2+} ion in the host material. The functional group and optical behavior of the crystals were identified from FTIR and UV-vis spectrum analysis. Electrical parameters such as dielectric constant, dielectric loss have been studied. The thermal stability of the compound was found out using TGA/DTA analysis. Second Harmonic Generation of the samples was confirmed by Kurtz-Perry powder technique. Magnetic properties of the crystals studied by VSM were also reported. The encouraging results show that the cobalt chloride doped LACC crystals have greater potential applications in optical devices. - Graphical abstract: Fig (a) and (b) shows the transparent, stable single crystals of pure and doped crystals were obtained using slow evaporation technique. The sizes of pure and doped crystals are 20×9×2 mm{sup 3} and 18×15×1 mm{sup 3} respectively. Fig (c) is the Hysteresis loop traced at room temperature for the pure and doped crystals explains the soft ferromagnetic nature of the doped crystal. The provision for changing the value of coercivity can be used for security, switching and sensing applications. - Highlights: • Defect free crystals of pure and Co{sup 2+} ion doped L-alanine cadmium chloride were grown. • The optical, dielectric and magnetic properties of pure crystals were enhanced by adding Co{sup 2+} ion. • High optical transmittance was obtained in the entire visible and IR region. • Addition of dopant to the pure crystal altered the coercivity. • Low dielectric

  2. The neuroanatomy of pure apraxia of speech in stroke.

    Science.gov (United States)

    Graff-Radford, Jonathan; Jones, David T; Strand, Edythe A; Rabinstein, Alejandro A; Duffy, Joseph R; Josephs, Keith A

    2014-02-01

    The left insula or Broca's area have been proposed as the neuroanatomical correlate for apraxia of speech (AOS) based on studies of patients with both AOS and aphasia due to stroke. Studies of neurodegenerative AOS suggest the premotor area and the supplementary motor areas as the anatomical correlates. The study objective was to determine the common infarction area in patients with pure AOS due to stroke. Patients with AOS and no or equivocal aphasia due to ischemic stroke were identified through a pre-existing database. Seven subjects were identified. Five had pure AOS, and two had equivocal aphasia. MRI lesion analysis revealed maximal overlap spanning the left premotor and motor cortices. While both neurodegenerative AOS and stroke induced pure AOS involve the premotor cortex, further studies are needed to establish whether stroke-induced AOS and neurodegenerative AOS share a common anatomic substrate. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Pure spinor formalism as an N = 2 topological string

    International Nuclear Information System (INIS)

    Berkovits, Nathan

    2005-01-01

    Following suggestions of Nekrasov and Siegel, a non-minimal set of fields are added to the pure spinor formalism for the superstring. Twisted c-circumflex = 3 N = 2 generators are then constructed where the pure spinor BRST operator is the fermionic spin-one generator, and the formalism is interpreted as a critical topological string. Three applications of this topological string theory include the super-Poincare covariant computation of multiloop superstring amplitudes without picture-changing operators, the construction of a cubic open superstring field theory without contact-term problems, and a new four-dimensional version of the pure spinor formalism which computes F-terms in the spacetime action

  4. Superposing pure quantum states with partial prior information

    Science.gov (United States)

    Dogra, Shruti; Thomas, George; Ghosh, Sibasish; Suter, Dieter

    2018-05-01

    The principle of superposition is an intriguing feature of quantum mechanics, which is regularly exploited in many different circumstances. A recent work [M. Oszmaniec et al., Phys. Rev. Lett. 116, 110403 (2016), 10.1103/PhysRevLett.116.110403] shows that the fundamentals of quantum mechanics restrict the process of superimposing two unknown pure states, even though it is possible to superimpose two quantum states with partial prior knowledge. The prior knowledge imposes geometrical constraints on the choice of input states. We discuss an experimentally feasible protocol to superimpose multiple pure states of a d -dimensional quantum system and carry out an explicit experimental realization for two single-qubit pure states with partial prior information on a two-qubit NMR quantum information processor.

  5. Pure Gravities via Color-Kinematics Duality for Fundamental Matter

    CERN Document Server

    Johansson, Henrik

    2015-01-01

    We give a prescription for the computation of loop-level scattering amplitudes in pure Einstein gravity, and four-dimensional pure supergravities, using the color-kinematics duality. Amplitudes are constructed using double copies of pure (super-)Yang-Mills parts and additional contributions from double copies of fundamental matter, which are treated as ghosts. The opposite-statistics states cancel the unwanted dilaton and axion in the bosonic theory, as well as the extra matter supermultiplets in supergravities. As a spinoff, we obtain a prescription for obtaining amplitudes in supergravities with arbitrary non-self-interacting matter. As a prerequisite, we extend the color-kinematics duality from the adjoint to the fundamental representation of the gauge group. We explain the numerator relations that the fundamental kinematic Lie algebra should satisfy. We give nontrivial evidence supporting our construction using explicit tree and loop amplitudes, as well as more general arguments.

  6. Pure state condition for the semi-classical Wigner function

    International Nuclear Information System (INIS)

    Ozorio de Almeida, A.M.

    1982-01-01

    The Wigner function W(p,q) is a symmetrized Fourier transform of the density matrix e(q 1 ,q 2 ), representing quantum-mechanical states or their statistical mixture in phase space. Identification of these two alternatives in the case of density matrices depends on the projection identity e 2 = e; its Wigner correspondence is the pure state condition. This criterion is applied to the Wigner functions botained from standard semiclassical wave functions, determining as pure states those whose classical invariant tori satisfy the generalized Bohr-Sommerfeld conditions. Superpositions of eigenstates are then examined and it is found that the Wigner function corresponding to Gaussian random wave functions are smoothed out in the manner of mixedstate Wigner functions. Attention is also given to the pure-state condition in the case where an angular coordinate is used. (orig.)

  7. Effect of Bound Entanglement on the Convertibility of Pure States

    International Nuclear Information System (INIS)

    Ishizaka, Satoshi

    2004-01-01

    I show that bound entanglement strongly influences the quantum entanglement processing of pure states: If N distant parties share appropriate bound entangled states with positive partial transpose, all N-partite pure entangled states become inter-convertible by stochastic local operations and classical communication (SLOCC) at the single copy level. This implies that the Schmidt rank of a bipartite pure entangled state can be increased, and that two incomparable tripartite entanglement of the GHZ and W type can be inter-converted by the assistance of bound entanglement. Further, I propose the simplest experimental scheme for the demonstration of the corresponding bound-entanglement-assisted SLOCC. This scheme does not need quantum gates and is feasible for the current experimental technology of linear optics

  8. Visibility in a pure model of golden spiral phyllotaxis.

    Science.gov (United States)

    Herrmann, Burghard

    2018-07-01

    This paper considers the geometry of plants with golden spiral phyllotaxis, i.e. growing leaf by leaf on a spiral with golden divergence angle, via the simplest mathematical model, a cylinder with regular arrangement of points on its surface. As is well-known, Fibonacci numbers appear by means of the order of parastichies. This fact is shown to be a straightforward application of logical consequences to a particular model with respect to pure visibility. This notion is very similar to that of contact parastichies. The 3-D cylindrical model of golden spiral phyllotaxis abstracts from the form of leaves and identifies them with points. Pure visibility is specified in the 2-D representation so that common sense parastichies can be scrutinized. The main Theorem states that the orders of the purely most visible parastichies are Fibonacci numbers. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Excitation of coherent propagating spin waves by pure spin currents.

    Science.gov (United States)

    Demidov, Vladislav E; Urazhdin, Sergei; Liu, Ronghua; Divinskiy, Boris; Telegin, Andrey; Demokritov, Sergej O

    2016-01-28

    Utilization of pure spin currents not accompanied by the flow of electrical charge provides unprecedented opportunities for the emerging technologies based on the electron's spin degree of freedom, such as spintronics and magnonics. It was recently shown that pure spin currents can be used to excite coherent magnetization dynamics in magnetic nanostructures. However, because of the intrinsic nonlinear self-localization effects, magnetic auto-oscillations in the demonstrated devices were spatially confined, preventing their applications as sources of propagating spin waves in magnonic circuits using these waves as signal carriers. Here, we experimentally demonstrate efficient excitation and directional propagation of coherent spin waves generated by pure spin current. We show that this can be achieved by using the nonlocal spin injection mechanism, which enables flexible design of magnetic nanosystems and allows one to efficiently control their dynamic characteristics.

  10. Instant PageSpeed optimization

    CERN Document Server

    Jaiswal, Sanjeev

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. Instant PageSpeed Optimization is a hands-on guide that provides a number of clear, step-by-step exercises for optimizing your websites for better performance and improving their efficiency.Instant PageSpeed Optimization is aimed at website developers and administrators who wish to make their websites load faster without any errors and consume less bandwidth. It's assumed that you will have some experience in basic web technologies like HTML, CSS3, JavaScript, and the basics of netw

  11. Raising the speed limit from 75 to 80mph on Utah rural interstates: Effects on vehicle speeds and speed variance.

    Science.gov (United States)

    Hu, Wen

    2017-06-01

    In November 2010 and October 2013, Utah increased speed limits on sections of rural interstates from 75 to 80mph. Effects on vehicle speeds and speed variance were examined. Speeds were measured in May 2010 and May 2014 within the new 80mph zones, and at a nearby spillover site and at more distant control sites where speed limits remained 75mph. Log-linear regression models estimated percentage changes in speed variance and mean speeds for passenger vehicles and large trucks associated with the speed limit increase. Logistic regression models estimated effects on the probability of passenger vehicles exceeding 80, 85, or 90mph and large trucks exceeding 80mph. Within the 80mph zones and at the spillover location in 2014, mean passenger vehicle speeds were significantly higher (4.1% and 3.5%, respectively), as were the probabilities that passenger vehicles exceeded 80mph (122.3% and 88.5%, respectively), than would have been expected without the speed limit increase. Probabilities that passenger vehicles exceeded 85 and 90mph were non-significantly higher than expected within the 80mph zones. For large trucks, the mean speed and probability of exceeding 80mph were higher than expected within the 80mph zones. Only the increase in mean speed was significant. Raising the speed limit was associated with non-significant increases in speed variance. The study adds to the wealth of evidence that increasing speed limits leads to higher travel speeds and an increased probability of exceeding the new speed limit. Results moreover contradict the claim that increasing speed limits reduces speed variance. Although the estimated increases in mean vehicle speeds may appear modest, prior research suggests such increases would be associated with substantial increases in fatal or injury crashes. This should be considered by lawmakers considering increasing speed limits. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  12. Effect of sterilization process on surface characteristics and biocompatibility of pure Mg and MgCa alloys

    International Nuclear Information System (INIS)

    Liu, X.L.; Zhou, W.R.; Wu, Y.H.; Cheng, Y.; Zheng, Y.F.

    2013-01-01

    The aim of this work was to investigate the effect of various sterilization methods on surface characteristics and biocompatibility of MgCa alloy, with pure Mg as a comparison, including steam autoclave sterilization (SA), ethylene oxide steam sterilization (EO), glutaraldehyde sterilization (GD), dry heat sterilization (DH) and Co60 γ ray radiation sterilization (R) technologies. The surface characterizations were performed by environmental scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, grazing incidence X-ray diffraction, water contact angle and surface free energy measurement, whereas the cytotoxicity and hemocompatibility were evaluated by cellular adhesive experiment, platelet adhesion and hemolysis test. The results showed that the five sterilization processes caused more changes on the surface of MgCa alloy than that on the surface of pure Mg. The GD sterilization caused the most obvious changes on the surface of the pure Mg, and the SA sterilization made the largest alteration on the MgCa alloy surface. The GD and DH sterilization processes could cause increases on surface free energy for both pure Mg and MgCa alloys, while the other three sterilization processes reduced the surface free energy. The DH and GD sterilization processes caused the least alteration on the cell adhesion on pure Mg surface, whereas the EO sterilization performed the greatest impact on the cell adhesion on the Mg–Ca alloy surface. The hemolysis percentage of pure Mg and MgCa alloys were reduced by SA sterilization, meanwhile the other four sterilization processes increased their hemolysis percentages significantly, especially for the EO sterilization. - Highlights: • The effect of sterilization on surface chemistry and biocompatibility was studied. • Sterilization caused more surface changes on MgCa alloy than pure Mg. • Co60 γ ray radiation is the most appropriate sterilization process

  13. Entanglement measure for general pure multipartite quantum states

    International Nuclear Information System (INIS)

    Heydari, Hoshang; Bjoerk, Gunnar

    2004-01-01

    We propose an explicit formula for a measure of entanglement of pure multipartite quantum states. We discuss the mathematical structure of the measure and give a brief explanation of its physical motivation. We apply the measure on some pure, tripartite, qubit states and demonstrate that, in general, the entanglement can depend on what actions are performed on the various subsystems, and specifically if the parties in possession of the subsystems cooperate or not. We also give some simple but illustrative examples of the entanglement of four-qubit and m-qubit states

  14. Pure spinors, free differential algebras, and the supermembrane

    International Nuclear Information System (INIS)

    Fre, Pietro; Grassi, Pietro Antonio

    2007-01-01

    The Lagrangian formalism for the supermembrane in any 11d supergravity background is constructed in the pure spinor framework. Our gauge-fixed action is manifestly BRST, supersymmetric, and 3d Lorentz invariant. The relation between the Free Differential Algebras (FDA) underlying 11d supergravity and the BRST symmetry of the membrane action is exploited. The 'gauge-fixing' has a natural interpretation as the variation of the Chevalley cohomology class needed for the extension of 11d super-Poincare superalgebra to M-theory FDA. We study the solution of the pure spinor constraints in full detail

  15. Pure spinors, free differential algebras, and the supermembrane

    Energy Technology Data Exchange (ETDEWEB)

    Fre, Pietro [Dipartimento di Fisica Teorica, Universita di Torino, and INFN-Sezione di Torino, Via P. Giuria 1, I-10125 Turin (Italy); Grassi, Pietro Antonio [Centro Studi e Ricerche E. Fermi, Compendio Viminale, I-00184 Rome (Italy) and DISTA, Universita del Piemonte Orientale, and INFN-Sezione di Torino, Via Bellini 25/G, Alessandria 15100 (Italy) and CERN, Theory Unit, CH-1211 Geneva 23 (Switzerland)]. E-mail: pgrassi@insti.physics.sunysb.edu

    2007-02-12

    The Lagrangian formalism for the supermembrane in any 11d supergravity background is constructed in the pure spinor framework. Our gauge-fixed action is manifestly BRST, supersymmetric, and 3d Lorentz invariant. The relation between the Free Differential Algebras (FDA) underlying 11d supergravity and the BRST symmetry of the membrane action is exploited. The 'gauge-fixing' has a natural interpretation as the variation of the Chevalley cohomology class needed for the extension of 11d super-Poincare superalgebra to M-theory FDA. We study the solution of the pure spinor constraints in full detail.

  16. On Pure and (approximate) Strong Equilibria of Facility Location Games

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Telelis, Orestis A.

    2008-01-01

    We study social cost losses in Facility Location games, where n selfish agents install facilities over a network and connect to them, so as to forward their local demand (expressed by a non-negative weight per agent). Agents using the same facility share fairly its installation cost, but every...... agent pays individually a (weighted) connection cost to the chosen location. We study the Price of Stability (PoS) of pure Nash equilibria and the Price of Anarchy of strong equilibria (SPoA), that generalize pure equilibria by being resilient to coalitional deviations. For unweighted agents on metric...

  17. Crystal structure of pure ZrO2 nanopowders

    International Nuclear Information System (INIS)

    Lamas, D.G.; Rosso, A.M.; Anzorena, M. Suarez; Fernandez, A.; Bellino, M.G.; Cabezas, M.D.; Walsoee de Reca, N.E.; Craievich, A.F.

    2006-01-01

    The crystal structure of pure (undoped) zirconia nanopowders synthesized by different wet-chemical routes has been investigated by synchrotron X-ray diffraction. Whereas some previous authors reported the retention of the cubic phase in similar materials, we demonstrate here that pure zirconia nanopowders with average crystallite sizes ranging from 5 to 10 nm exhibit the tetragonal phase. In addition, our results suggest that a tetragonal-to-cubic transition for decreasing crystallite size could eventually occur at a very small critical crystallite size

  18. Model answers in pure mathematics for a-level students

    CERN Document Server

    Pratt, GA; Schofield, C W

    1967-01-01

    Model Answers in Pure Mathematics for A-Level Students provides a set of solutions that indicate what is required and expected in an Advanced Level examination in Pure Mathematics. This book serves as a guide to the length of answer required, layout of the solution, and methods of selecting the best approach to any particular type of math problem. This compilation intends to supplement, not replace, the normal textbook and provides a varied selection of questions for practice in addition to the worked solutions. The subjects covered in this text include algebra, trigonometry, coordinate geomet

  19. Probabilistic teleportation of an arbitrary pure state of two atoms

    Institute of Scientific and Technical Information of China (English)

    Yang Zhen-Biao; Wu Huai-Zhi; Su Wan-Jun

    2007-01-01

    In the context of microwave cavity QED, this paper proposes a new scheme for teleportation of an arbitrary pure state of two atoms. The scheme is very different from the previous ones which achieve the integrated state measurement,it deals in a probabilistic but simplified way. In the scheme, no additional atoms are involved and thus only two atoms are required to be detected. The scheme can also be used for the teleportation of arbitrary pure states of many atoms or two-mode cavities.

  20. A methodology to generate statistically dependent wind speed scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Morales, J.M.; Conejo, A.J. [Department of Electrical Engineering, Univ. Castilla - La Mancha, Campus Universitario s/n, 13071 Ciudad Real (Spain); Minguez, R. [Environmental Hydraulics Institute ' ' IH Cantabria' ' , Univ. Cantabria, Avenida de los Castros s/n, 39005 Santander (Spain)

    2010-03-15

    Wind power - a renewable energy source increasingly attractive from an economic viewpoint - constitutes an electricity production alternative of growing relevance in current electric energy systems. However, wind power is an intermittent source that cannot be dispatched at the will of the producer. Modeling wind power production requires characterizing wind speed at the sites where the wind farms are located. The wind speed at a particular location can be described through a stochastic process that is spatially correlated with the stochastic processes describing wind speeds at other locations. This paper provides a methodology to characterize the stochastic processes pertaining to wind speed at different geographical locations via scenarios. Each one of these scenarios embodies time dependencies and is spatially dependent of the scenarios describing other wind stochastic processes. The scenarios generated by the proposed methodology are intended to be used within stochastic programming decision models to make informed decisions pertaining to wind power production. The methodology proposed is accurate in reproducing wind speed historical series as well as computationally efficient. A comprehensive case study is used to illustrate the capabilities of the proposed methodology. Appropriate conclusions are finally drawn. (author)

  1. A methodology to generate statistically dependent wind speed scenarios

    International Nuclear Information System (INIS)

    Morales, J.M.; Minguez, R.; Conejo, A.J.

    2010-01-01

    Wind power - a renewable energy source increasingly attractive from an economic viewpoint - constitutes an electricity production alternative of growing relevance in current electric energy systems. However, wind power is an intermittent source that cannot be dispatched at the will of the producer. Modeling wind power production requires characterizing wind speed at the sites where the wind farms are located. The wind speed at a particular location can be described through a stochastic process that is spatially correlated with the stochastic processes describing wind speeds at other locations. This paper provides a methodology to characterize the stochastic processes pertaining to wind speed at different geographical locations via scenarios. Each one of these scenarios embodies time dependencies and is spatially dependent of the scenarios describing other wind stochastic processes. The scenarios generated by the proposed methodology are intended to be used within stochastic programming decision models to make informed decisions pertaining to wind power production. The methodology proposed is accurate in reproducing wind speed historical series as well as computationally efficient. A comprehensive case study is used to illustrate the capabilities of the proposed methodology. Appropriate conclusions are finally drawn.

  2. Image tuning techniques for enhancing the performance of pure permanent magnet undulators with small gap/period ratios

    Energy Technology Data Exchange (ETDEWEB)

    Tatchyn, R. [Stanford Univ., CA (United States)

    1995-12-31

    The on-axis field of a small-gap undulator constricted out of pure permanent magnet (PM) blocks arranged in an alternating-dipole (i.e., 2 dipoles/period) array can be substantially varied by positioning monolithic permeable plates above and below the undulator jaws. This simple technique, which can be used to control the 1st harmonic energy in conventional synchrotron radiation (SR) or Free Electron Laser (FEL) applications requiring sub-octave tuning, can also be shown to suppress magnetic inhomogeneities that can contribute to the undulator`s on-axis field errors. If a standard 4 block/period Halbach undulator, composed of PM blocks with square cross sections, is rearranged into an alternating-dipole array with the same period, the peak field that can be generated with superimposed image plates can substantially exceed that of the pure-PM Halbach array. This design technique, which can be viewed as intermediate between the {open_quotes}pure-PM{close_quotes} and standard {open_quotes}hybrid/PM{close_quotes} configurations, provides a potentially cost-effective method of enhancing the performance of small-gap, pure-PM insertion devices. In this paper we report on the analysis and recent characterization of pure-PM undulator structures with superimposed image plates, and discuss possible applications to FEL research.

  3. Idealized models of the joint probability distribution of wind speeds

    Science.gov (United States)

    Monahan, Adam H.

    2018-05-01

    The joint probability distribution of wind speeds at two separate locations in space or points in time completely characterizes the statistical dependence of these two quantities, providing more information than linear measures such as correlation. In this study, we consider two models of the joint distribution of wind speeds obtained from idealized models of the dependence structure of the horizontal wind velocity components. The bivariate Rice distribution follows from assuming that the wind components have Gaussian and isotropic fluctuations. The bivariate Weibull distribution arises from power law transformations of wind speeds corresponding to vector components with Gaussian, isotropic, mean-zero variability. Maximum likelihood estimates of these distributions are compared using wind speed data from the mid-troposphere, from different altitudes at the Cabauw tower in the Netherlands, and from scatterometer observations over the sea surface. While the bivariate Rice distribution is more flexible and can represent a broader class of dependence structures, the bivariate Weibull distribution is mathematically simpler and may be more convenient in many applications. The complexity of the mathematical expressions obtained for the joint distributions suggests that the development of explicit functional forms for multivariate speed distributions from distributions of the components will not be practical for more complicated dependence structure or more than two speed variables.

  4. High-speed holographic camera

    International Nuclear Information System (INIS)

    Novaro, Marc

    The high-speed holographic camera is a disgnostic instrument using holography as an information storing support. It allows us to take 10 holograms, of an object, with exposures times of 1,5ns, separated in time by 1 or 2ns. In order to get these results easily, no mobile part is used in the set-up [fr

  5. Processing Determinants of Reading Speed.

    Science.gov (United States)

    Jackson, Mark D.; McClelland, James L.

    1979-01-01

    Two groups of undergraduates differing in reading ability were tested on a number of reaction-time tasks designed to determine the speed of encoding visual information at several different levels, tests of sensory functions, verbal and quantitative reasoning ability, short-term auditory memory span, and ability to comprehend spoken text.…

  6. The Speeding Car Design Challenge

    Science.gov (United States)

    Roman, Harry T.

    2009-01-01

    All too often, one reads about high-speed police chases in pursuit of stolen cars that result in death and injury to people and innocent bystanders. Isn't there another way to accomplish the apprehension of the thieves that does not put people at such great risk? This article presents a classroom challenge to use technology to remotely shutdown…

  7. Visual Processing Speeds in Children

    Directory of Open Access Journals (Sweden)

    Steve Croker

    2011-01-01

    Full Text Available The aim of this study was to investigate visual processing speeds in children. A rapid serial visual presentation (RSVP task with schematic faces as stimuli was given to ninety-nine 6–10-year-old children as well as a short form of the WISC-III. Participants were asked to determine whether a happy face stimulus was embedded in a stream of distracter stimuli. Presentation time was gradually reduced from 500 ms per stimulus to 100 ms per stimulus, in 50 ms steps. The data revealed that (i RSVP speed increases with age, (ii children aged 8 years and over can discriminate stimuli presented every 100 ms—the speed typically used with RSVP procedures in adult and adolescent populations, and (iii RSVP speed is significantly correlated with digit span and object assembly. In consequence, the RSVP paradigm presented here is appropriate for use in further investigations of processes of temporal attention within this cohort.

  8. NASA low speed centrifugal compressor

    Science.gov (United States)

    Hathaway, Michael D.

    1990-01-01

    The flow characteristics of a low speed centrifugal compressor were examined at NASA Lewis Research Center to improve understanding of the flow in centrifugal compressors, to provide models of various flow phenomena, and to acquire benchmark data for three dimensional viscous flow code validation. The paper describes the objectives, test facilities' instrumentation, and experiment preliminary comparisons.

  9. Perils of using speed zone data to assess real-world compliance to speed limits.

    Science.gov (United States)

    Chevalier, Anna; Clarke, Elizabeth; Chevalier, Aran John; Brown, Julie; Coxon, Kristy; Ivers, Rebecca; Keay, Lisa

    2017-11-17

    Real-world driving studies, including those involving speeding alert devices and autonomous vehicles, can gauge an individual vehicle's speeding behavior by comparing measured speed with mapped speed zone data. However, there are complexities with developing and maintaining a database of mapped speed zones over a large geographic area that may lead to inaccuracies within the data set. When this approach is applied to large-scale real-world driving data or speeding alert device data to determine speeding behavior, these inaccuracies may result in invalid identification of speeding. We investigated speeding events based on service provider speed zone data. We compared service provider speed zone data (Speed Alert by Smart Car Technologies Pty Ltd., Ultimo, NSW, Australia) against a second set of speed zone data (Google Maps Application Programming Interface [API] mapped speed zones). We found a systematic error in the zones where speed limits of 50-60 km/h, typical of local roads, were allocated to high-speed motorways, which produced false speed limits in the speed zone database. The result was detection of false-positive high-range speeding. Through comparison of the service provider speed zone data against a second set of speed zone data, we were able to identify and eliminate data most affected by this systematic error, thereby establishing a data set of speeding events with a high level of sensitivity (a true positive rate of 92% or 6,412/6,960). Mapped speed zones can be a source of error in real-world driving when examining vehicle speed. We explored the types of inaccuracies found within speed zone data and recommend that a second set of speed zone data be utilized when investigating speeding behavior or developing mapped speed zone data to minimize inaccuracy in estimates of speeding.

  10. Low Speed Control for Automatic Welding

    Science.gov (United States)

    Iceland, W. E.

    1982-01-01

    Amplifier module allows rotating positioner of automatic welding machine to operate at speeds below normal range. Low speeds are precisely regulated by a servomechanism as are normal-range speeds. Addition of module to standard welding machine makes it unnecessary to purchase new equipment for low-speed welding.

  11. Effective speed management through automatic enforcement.

    NARCIS (Netherlands)

    Oei, H.-l.

    1994-01-01

    This paper analyses several aspects of the Dutch experience of speed enforcement, and presents the results of some speed management experiments in The Netherlands, using automatic warning of speeders and enforcement of speeding. Traditional approaches to manage speed there have not resulted in

  12. Improving homogeneity by dynamic speed limit systems.

    NARCIS (Netherlands)

    Nes, N. van Brandenberg, S. & Twisk, D.A.M.

    2010-01-01

    Homogeneity of driving speeds is an important variable in determining road safety; more homogeneous driving speeds increase road safety. This study investigates the effect of introducing dynamic speed limit systems on homogeneity of driving speeds. A total of 46 subjects twice drove a route along 12

  13. Speed Optimization in Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    In the Liner Shipping Network Design Problem (LSNDP) services sail at a given speed throughout a round trip. In reality most services operate with a speed differentiated head- and back-haul, or even individual speeds on every sailing between two ports. The speed of a service is decisive...

  14. Mobile app reading speed test.

    Science.gov (United States)

    Kingsnorth, Alec; Wolffsohn, James S

    2015-04-01

    To validate the accuracy and repeatability of a mobile app reading speed test compared with the traditional paper version. Twenty-one subjects wearing their full refractive correction glasses read 14 sentences of decreasing print size between 1.0 and -0.1 logMAR, each consisting of 14 words (Radner reading speed test) at 40 cm with a paper-based chart and twice on iPad charts. Time duration was recorded with a stop watch for the paper chart and on the App itself for the mobile chart allowing critical print size (CPS) and optimal reading speed (ORS) to be derived objectively. The ORS was higher for the mobile app charts (194±29 wpm; 195±25 wpm) compared with the paper chart (166±20 wpm; F=57.000, pmobile app charts (0.17±0.20 logMAR; 0.18±0.17 logMAR) compared with the paper chart (0.25±0.17 logMAR; F=5.406, p=0.009). The mobile app test had a mean difference repeatability of 0.30±22.5 wpm, r=0.917 for ORS, and a CPS of 0.0±0.2 logMAR, r=0.769. Repeatability of the app reading speed test is as good (ORS) or better (CPS) than previous studies on the paper test. While the results are not interchangeable with paper-based charts, mobile app tablet-based tests of reading speed are reliable and rapid to perform, with the potential to capture functional visual ability in research studies and clinical practice. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Bertrand Competition with Asymmetric Costs: A Solution in Pure Strategies

    NARCIS (Netherlands)

    Demuynck, Thomas; Herings, P. Jean-Jacques; Saulle, Riccardo D.; Seel, Christian

    2018-01-01

    We consider two versions of a Bertrand duopoly with asymmetric costs and homogeneous goods. They differ in whether predatory pricing is allowed. For each version, we derive the Myopic Stable Set in pure strategies as introduced by Demuynck, Herings, Saulle, and Seel (2017). We contrast our

  16. Developmental and Individual Differences in Pure Numerical Estimation

    Science.gov (United States)

    Booth, Julie L.; Siegler, Robert S.

    2006-01-01

    The authors examined developmental and individual differences in pure numerical estimation, the type of estimation that depends solely on knowledge of numbers. Children between kindergarten and 4th grade were asked to solve 4 types of numerical estimation problems: computational, numerosity, measurement, and number line. In Experiment 1,…

  17. Pure motor hemiparesis in a case of vertebrobasilar arterial ectasia

    Energy Technology Data Exchange (ETDEWEB)

    Milandre, L. (Dept. of Neurology, CHU Timone, Marseille (France)); Martini, P. (Dept. of Neuroradiology, CHU Timone, Marseille (France)); Perot, S. (Dept. of Neuroradiology, CHU Timone, Marseille (France)); Mercier, C. (Dept. of Vascular Surgery, CHU Timone, Marseille (France))

    1993-03-01

    A case of pure motor hemiparesis due to a pontine lacunar infarct is reported. Infaction was related to vertebrobasilar ectasia identified on CT, MRI and MR angiography. MR studies provide accurate information on anatomical location, residual lumen, partial thrombosis, mass effect on brain stem and CSF pathways and vascular complications. (orig.)

  18. Pure red cell aplasia following irradiation of an asymptomatic thymoma

    International Nuclear Information System (INIS)

    Shibata, Kazuo; Masaoka, Akira; Mizuno, Takeo; Ichimura, Hideki

    1982-01-01

    An unusual case of pure red-cell aplasia (PRCA) developed sixteen days after irradiation of an asymptomatic thymoma. After removal of the encapsulated thymoma there was no improvement in the anemia, and no response to adrenocortical and anabolic steroid hormones or immunosuppressive agents. (author)

  19. Adults Studying Pure Mathematics in Adult Tertiary Preparation.

    Science.gov (United States)

    Bennison, Anne

    2002-01-01

    Investigated the experiences of a group of adults enrolled in the Pure Mathematics module of the Certificate IV in Adult Tertiary Preparation in 2000 at one of the Institutes of TAFE in Brisbane, Australia. Classroom learning experiences, exposure to technology, and the impact of returning to study on other facets of students' lives were…

  20. Complex windmill transformation producing new purely magnetic fluids

    International Nuclear Information System (INIS)

    Lozanovski, C; Wylleman, L

    2011-01-01

    Minimal complex windmill transformations of G 2 IB(ii) spacetimes (admitting a two-dimensional Abelian group of motions of the so-called Wainwright B(ii) class) are defined and the compatibility with a purely magnetic Weyl tensor is investigated. It is shown that the transformed spacetimes cannot be perfect fluids or purely magnetic Einstein spaces. We then determine which purely magnetic perfect fluids (PMpfs) can be windmill-transformed into purely magnetic anisotropic fluids (PMafs). Assuming separation of variables, complete integration produces two, algebraically general, G 2 I-B(ii) PMpfs: a solution with zero 4-acceleration vector and spatial energy-density gradient, previously found by the authors, and a new solution in terms of Kummer's functions, where these vectors are aligned and non-zero. The associated windmill PMafs are rotating but non-expanding. Finally, an attempt to relate the spacetimes to each other by a simple procedure leads to a G 2 I-B(ii) one-parameter PMaf generalization of the previously found metric.