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Sample records for band profiles experimental

  1. Morphological effects on IR band profiles: Experimental spectroscopic analysis with application to observed spectra of oxygen-rich AGB stars

    CERN Document Server

    Tamanai, A; Blum, J; Posch, Th; Koike, C; Ferguson, J W

    2009-01-01

    To trace the source of the unique 13, 19.5, and 28 $\\mu$m emission features in the spectra of oxygen-rich circumstellar shells around AGB stars, we have compared dust extinction spectra obtained by aerosol measurements. We have measured the extinction spectra for 19 oxide powder samples of eight different types, such as Ti-compounds (TiO, TiO$_2$, Ti$_2$O$_3$, Ti$_3$O$_5$, Al$_2$TiO$_5$, CaTiO$_3$), $\\alpha$-, $\\gamma$-, $\\chi$-$\\delta$-$\\kappa$-Al$_2$O$_3$, and MgAl$_2$O$_4$ in the infrared region (10 - 50 $\\mu$m) paying special attention to the morphological (size, shape, and agglomeration) effects and the differences in crystal structure. Anatase (TiO$_2$) particles with rounded edges are the possible 13, 19.5 and 28 $\\mu$m band carriers as the main contributor in the spectra of AGB stars, and spherically shaped nano-sized spinel and Al$_2$TiO$_5$ dust grains are possibly associated with the anatase, enhancing the prominence of the 13 $\\mu$m feature and providing additional features at 28 $\\mu$m. The extin...

  2. Experimental study on the adiabatic shear bands

    International Nuclear Information System (INIS)

    Four martensitic steels (Z50CDV5 steel, 28CND8 steel, 35NCDV16 steel and 4340 steel) with different hardness between 190 and 600 Hsub(B) (Brinell hardness), have been studied by means of dynamic compressive tests on split Hopkinson pressure bar. Microscopic observations show that the fracture are associated to the development of adiabatic shear bands (except 4340 steel with 190 Hsub(B) hardness). By means of tests for which the deformation is stopped at predetermined levels, the measurement of shear and hardness inside the band and the matrix indicates the chronology of this phenomenon: first the localization of shear, followed by the formation of adiabatic shear band and ultimatly crack initiation and propagation. These results correlated with few simulations by finite elements have permitted to suggest two mecanisms of deformation leading to the formation of adiabatic shear bands in this specific test

  3. Surface Resonance Bands on (001)W: Experimental Dispersion Relations

    DEFF Research Database (Denmark)

    Willis, R. F.; Feuerbacher, B.; Christensen, N. Egede

    1977-01-01

    A band of unbound surface states (resonances), located in an energy region above the vacuum threshold corresponding to an energy band gap in the electron states of the bulk crystal, has been observed by angle-resolved secondary-electron-emission spectroscopy. The experimental dispersion behavior ...

  4. Low-profile metamaterial-based L-band antennas

    Science.gov (United States)

    Burokur, Shah Nawaz; Lepage, Anne-Claire; Varault, Stefan; Begaud, Xavier; Piau, Gérard-Pascal; de Lustrac, André

    2016-04-01

    The aim of the present contribution is to show that metasurfaces such as reactive impedance surfaces (RIS) and artificial magnetic conductors can be efficiently used in the design of low-profile circularly polarized L-band antennas. We present the design and simulation of the compact and low-profile antennas. The solution based on RIS will be compared to a circularly polarized microstrip patch antenna using the same materials in order to prove the benefit of metasurfaces. The engineered metasurfaces allow increasing the bandwidths with few modifications on the thickness and the overall antenna size.

  5. Improvement of band gap profile in Cu(InGa)Se2 solar cells through rapid thermal annealing

    International Nuclear Information System (INIS)

    Highlights: • Proper RTA treatment can effectively optimize band gap profile to more expected level. • Inter-diffusion of atoms account for the improvement of the graded band gap profile. • The variation of the band gap profile created an absolute gain in the efficiency by 1.22%. - Abstract: In the paper, the effect of rapid thermal annealing on non-optimal double-graded band gap profiles was investigated by using X-ray photoelectron spectroscopy and capacitance–voltage measurement techniques. Experimental results revealed that proper rapid thermal annealing treatment can effectively improve band gap profile to more optimal level. The annealing treatment could not only reduce the values of front band gap and minimum band gap, but also shift the position of the minimum band gap toward front electrode and enter into space charge region. In addition, the thickness of Cu(InGa)Se2 thin film decreased by 25 nm after rapid thermal annealing treatment. All of these modifications were attributed to the inter-diffusion of atoms during thermal treatment process. Simultaneously, the variation of the band gap profile created an absolute gain in the efficiency by 1.22%, short-circuit current density by 2.16 mA/cm2 and filled factor by 3.57%

  6. Experimental demonstration of a W-band gyroklystron amplifier

    OpenAIRE

    Blank, M.; Danly, B.; Levush, B.; Latham, P; Pershing, D.

    1997-01-01

    The experimental demonstration of a four cavity W-band (93 GHz) gyroklystron amplifier is reported. The gyroklystron has produced 67 kW peak output power and 28% efficiency in the TE011 mode using a 55 kV, 4.3 A electron beam. The full width at half maximum instantaneous bandwidth is greater than 460 MHz, a significant increase over the bandwidth demonstrated in previous W-band gyroklystron amplifier experiments. The amplifier is unconditionally stable at this operating point. Experimental re...

  7. Experimental Demonstration of a W-Band Gyroklystron Amplifier

    Science.gov (United States)

    Blank, M.; Danly, B. G.; Levush, B.; Latham, P. E.; Pershing, D. E.

    1997-12-01

    The experimental demonstration of a four cavity W-band (93 GHz) gyroklystron amplifier is reported. The gyroklystron has produced 67 kW peak output power and 28% efficiency in the TE011 mode using a 55 kV, 4.3 A electron beam. The full width at half maximum instantaneous bandwidth is greater than 460 MHz, a significant increase over the bandwidth demonstrated in previous W-band gyroklystron amplifier experiments. The amplifier is unconditionally stable at this operating point. Experimental results are in good agreement with theoretical predictions.

  8. Experimental radio frequency link for Ka-band communications applications

    Science.gov (United States)

    Fujikawa, Gene; Conray, Martin J.; Saunders, Alan L.; Pope, Dale E.

    1988-01-01

    An experimental radio frequency link has been demonstrated to provide two-way communication between a remote user ground terminal and a ground-based Ka-band transponder. Bit-error-rate performance and radio frequency characteristics of the communication link were investigated.

  9. Experimental equatorial ionospheric profiles and IRI model

    International Nuclear Information System (INIS)

    Ionospheric profiles below the F2 peak ionization density are compared with those of the International Reference Ionosphere (IRI). The data used are those of Ibadan (Lat. 7.4 deg. N, Long. 3,9 deg. E). The results show that at low solar activity, the greatest difference between the model and experimental observation occurred in winter and September equinox, when the IRI model gives a thinner bottomside ionization density. During the summer and March equinox of this solar epoch, the major difference occurs only around the F1 region, where the model gives a lower electron density than what it observed experimentally. The difference in summer is not as great as that observed during the March equinox. At high solar activity, the model is close to observed profile, from the F2 peak down to a height around the point where electron density is half of the F2 peak density (h 0.5). From the h 0.5 to the height of the E layer peak, the IRI model gives a lower electron density than what it observed experimentally. The discrepancy is least during the March equinox season. Some suggestions are made for the improvement of the model. (author). 7 refs, 4 figs

  10. Experimental Investigation of a W-Band Gyroklystron Amplifier

    Science.gov (United States)

    Blank, Monica; Danly, Bruce; Levush, Baruch; Latham, Peter

    1997-05-01

    A four cavity W-band gyroklystron amplifier experiment is currently underway at the Naval Research laboratory. The gyroklystron has produced 55.5 kW peak output power and 23.5% efficiency in the TE_01 mode with a 56 kV, 4.2 A electron beam. The -3 dB bandwidth is greater than 400 MHz. The small signal and saturated gains are 36 dB and 28 dB, respectively. A time dependent version of the non-linear code MAGYKL (P.E. Latham, W. Lawson, V. Irwin, IEEE Trans. Plasma Sci., Vol. 22, No. 5, pp. 804-817, 1994.) was developed to design the interaction circuit. Theoretical performance predictions are in good agreement with experimental results. Details of the circuit design, comparisons of theory with measured data, and plans for future experiments will be presented.

  11. Experimental reconstruction of Wilson lines in Bloch bands

    OpenAIRE

    Li, Tracy; Duca, Lucia; Reitter, Martin; Grusdt, Fabian; Demler, Eugene; Endres, Manuel; Schleier-Smith, Monika; BLOCH, Immanuel; Schneider, Ulrich

    2015-01-01

    Topology and geometry are essential to our understanding of modern physics, underlying many foundational concepts from high energy theories, quantum information, and condensed matter physics. In condensed matter systems, a wide range of phenomena stem from the geometry of the band eigenstates, which is encoded in the matrix-valued Wilson line for general multi-band systems. By realizing strong-force dynamics in Bloch bands that are described by Wilson lines, we observe an evolution of band po...

  12. Neuropsychological Profile of Children with Subcortical Band Heterotopia

    Science.gov (United States)

    Spencer-Smith, Megan; Leventer, Richard; Jacobs, Rani; De Luca, Cinzia; Anderson, Vicki

    2009-01-01

    Aim: Subcortical band heterotopia (SBH) or "double cortex" is a malformation of cortical development resulting from impaired neuronal migration. So far, research has focused on the neurological, neuroimaging, and genetic correlates of SBH. More recently, clinical reports and small sample studies have documented neuropsychological dysfunction in…

  13. Quantitative o perando visualization of the energy band depth profile in solar cells

    OpenAIRE

    Chen, Qi; Mao, Lin; LI, YAOWEN; Kong, Tao; Wu, Na; Ma, Changqi; Bai, Sai; Jin, Yizheng; Wu, Dan; Lu, Wei; Wang, Bing; Chen, Liwei

    2015-01-01

    The energy band alignment in solar cell devices is critically important because it largely governs elementary photovoltaic processes, such as the generation, separation, transport, recombination and collection of charge carriers. Despite the expenditure of considerable effort, the measurement of energy band depth profiles across multiple layers has been extremely challenging, especially for operando devices. Here we present direct visualization of the surface potential depth profile over the ...

  14. Radiometric Study of Soil Profiles in the Infrared Band

    Science.gov (United States)

    Ponomareva, T. V.; Ponomarev, E. I.

    2016-02-01

    The applicability of radiometric survey of soil profiles in the infrared range for the analysis of soil physical properties was studied. Radiometric data were obtained for different dates of the growing season for a number of soil profiles. The specificity of temperature profiles of texture-differentiated soils (Luvisols and Retisols) as related to weather conditions of the growing season was examined. The correlation analysis showed a close relationship between the air and surface soil temperatures and between the radiometric and thermodynamic soil temperatures in the upper 10 cm. In the studied profiles, the gradient of radiometric temperatures reached 0.5-0.8°C/cm in the humus horizons and sharply decreased at the depth of more than 15-20 cm. The gradient analysis of radiometric images made it possible to outline the boundaries of soil horizons. For the texture-differentiated soils, the most distinct boundaries were established between the gray-humus AY horizon and the underlying eluvial EL horizon in podzolic soils and between the AY horizon and the underlying humus-eluvial AEL horizon in gray soils.

  15. Experimental reconstruction of Wilson lines in Bloch bands

    OpenAIRE

    Li, Tracy; Duca, Lucia; Reitter, Martin; Grusdt, Fabian; Demler, Eugene; Endres, Manuel; Schleier-Smith, Monika; Bloch, Immanuel; Schneider, Ulrich

    2015-01-01

    Topology and geometry are essential to our understanding of modern physics, underlying many foundational concepts from high energy theories, quantum information, and condensed matter physics. In condensed matter systems, a wide range of phenomena stem from the geometry of the band eigenstates, which is encoded in the matrix-valued Wilson line for general multi-band systems. By realizing strong-force dynamics in Bloch bands that are described by Wilson lines, we observe an ev...

  16. Geometrical constraint experimental determination of Raman lidar overlap profile.

    Science.gov (United States)

    Li, Jian; Li, Chengcai; Zhao, Yiming; Li, Jing; Chu, Yiqi

    2016-06-20

    A simple experimental method to determine the overlap profile of Raman lidar is presented in this paper. Based on Mie and Raman backscattering signals and a geometrically constrained condition, the overlap profile of a Raman lidar system can be determined. Our approach simultaneously retrieves the lidar ratio of aerosols, which is one of the most important sources of uncertainty in the overlap profile determination. The results indicate that the overlap factor is significantly influenced by the lidar ratio in experimental methods. A representative case study indicates that the correction of the overlap profile obtained by this method is practical and feasible. PMID:27409119

  17. Tuning of photocatalytic reduction by conduction band engineering of semiconductor quantum dots with experimental evaluation of the band edge potential.

    Science.gov (United States)

    Suzuki, Takafumi; Watanabe, Hiroto; Oaki, Yuya; Imai, Hiroaki

    2016-05-01

    The conduction band edge (CBE) of WO3 quantum dots (QDs) was determined experimentally and engineered by size control to around one nanometer. Photocatalytic reactions of proton and molecular oxygen were tuned by changing the CBE of WO3-QDs. PMID:27075304

  18. Wide-band, low-frequency pulse profiles of 100 radio pulsars with LOFAR

    Science.gov (United States)

    Pilia, M.; Hessels, J. W. T.; Stappers, B. W.; Kondratiev, V. I.; Kramer, M.; van Leeuwen, J.; Weltevrede, P.; Lyne, A. G.; Zagkouris, K.; Hassall, T. E.; Bilous, A. V.; Breton, R. P.; Falcke, H.; Grießmeier, J.-M.; Keane, E.; Karastergiou, A.; Kuniyoshi, M.; Noutsos, A.; Osłowski, S.; Serylak, M.; Sobey, C.; ter Veen, S.; Alexov, A.; Anderson, J.; Asgekar, A.; Avruch, I. M.; Bell, M. E.; Bentum, M. J.; Bernardi, G.; Bîrzan, L.; Bonafede, A.; Breitling, F.; Broderick, J. W.; Brüggen, M.; Ciardi, B.; Corbel, S.; de Geus, E.; de Jong, A.; Deller, A.; Duscha, S.; Eislöffel, J.; Fallows, R. A.; Fender, R.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Gunst, A. W.; Hamaker, J. P.; Heald, G.; Horneffer, A.; Jonker, P.; Juette, E.; Kuper, G.; Maat, P.; Mann, G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Miller-Jones, J. C. A.; Nelles, A.; Paas, H.; Pandey-Pommier, M.; Pietka, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Röttgering, H.; Rowlinson, A.; Schwarz, D.; Smirnov, O.; Steinmetz, M.; Stewart, A.; Swinbank, J. D.; Tagger, M.; Tang, Y.; Tasse, C.; Thoudam, S.; Toribio, M. C.; van der Horst, A. J.; Vermeulen, R.; Vocks, C.; van Weeren, R. J.; Wijers, R. A. M. J.; Wijnands, R.; Wijnholds, S. J.; Wucknitz, O.; Zarka, P.

    2016-02-01

    Context. LOFAR offers the unique capability of observing pulsars across the 10-240 MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well suited for studying the frequency evolution of pulse profile morphology caused by both intrinsic and extrinsic effects such as changing emission altitude in the pulsar magnetosphere or scatter broadening by the interstellar medium, respectively. Aims: The magnitude of most of these effects increases rapidly towards low frequencies. LOFAR can thus address a number of open questions about the nature of radio pulsar emission and its propagation through the interstellar medium. Methods: We present the average pulse profiles of 100 pulsars observed in the two LOFAR frequency bands: high band (120-167 MHz, 100 profiles) and low band (15-62 MHz, 26 profiles). We compare them with Westerbork Synthesis Radio Telescope (WSRT) and Lovell Telescope observations at higher frequencies (350 and 1400 MHz) to study the profile evolution. The profiles were aligned in absolute phase by folding with a new set of timing solutions from the Lovell Telescope, which we present along with precise dispersion measures obtained with LOFAR. Results: We find that the profile evolution with decreasing radio frequency does not follow a specific trend; depending on the geometry of the pulsar, new components can enter into or be hidden from view. Nonetheless, in general our observations confirm the widening of pulsar profiles at low frequencies, as expected from radius-to-frequency mapping or birefringence theories. We offer this catalogue of low-frequency pulsar profiles in a user friendly way via the EPN Database of Pulsar Profiles, http://www.epta.eu.org/epndb/

  19. Wide-Band, Low-Frequency Pulse Profiles of 100 Radio Pulsars with LOFAR

    CERN Document Server

    Pilia, M; Stappers, B W; Kondratiev, V I; Kramer, M; van Leeuwen, J; Weltevrede, P; Lyne, A G; Zagkouris, K; Hassall, T E; Bilous, A V; Breton, R P; Falcke, H; Grießmeier, J -M; Keane, E; Karastergiou, A; Kuniyoshi, M; Noutsos, A; Osłowski, S; Serylak, M; Sobey, C; ter Veen, S; Alexov, A; Anderson, J; Asgekar, A; Avruch, I M; Bell, M E; Bentum, M J; Bernardi, G; Bîrzan, L; Bonafede, A; Breitling, F; Broderick, J W; Brüggen, M; Ciardi, B; Corbel, S; de Geus, E; de Jong, A; Deller, A; Duscha, S; Eislöffel, J; Fallows, R A; Fender, R; Ferrari, C; Frieswijk, W; Garrett, M A; Gunst, A W; Hamaker, J P; Heald, G; Horneffer, A; Jonker, P; Juette, E; Kuper, G; Maat, P; Mann, G; Markoff, S; McFadden, R; McKay-Bukowski, D; Miller-Jones, J C A; Nelles, A; Paas, H; Pandey-Pommier, M; Pietka, M; Pizzo, R; Polatidis, A G; Reich, W; Röttgering, H; Rowlinson, A; Schwarz, D; Smirnov, O; Steinmetz, M; Stewart, A; Swinbank, J D; Tagger, M; Tang, Y; Tasse, C; Thoudam, S; Toribio, M C; van der Horst, A J; Vermeulen, R; Vocks, C; van Weeren, R J; Wijers, R A M J; Wijnands, R; Wijnholds, S J; Wucknitz, O; Zarka, P

    2015-01-01

    LOFAR offers the unique capability of observing pulsars across the 10-240 MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well-suited for studying the frequency evolution of pulse profile morphology caused by both intrinsic and extrinsic effects: such as changing emission altitude in the pulsar magnetosphere or scatter broadening by the interstellar medium, respectively. The magnitude of most of these effects increases rapidly towards low frequencies. LOFAR can thus address a number of open questions about the nature of radio pulsar emission and its propagation through the interstellar medium. We present the average pulse profiles of 100 pulsars observed in the two LOFAR frequency bands: High Band (120-167 MHz, 100 profiles) and Low Band (15-62 MHz, 26 profiles). We compare them with Westerbork Synthesis Radio Telescope (WSRT) and Lovell Telescope observations at higher frequencies (350 and1400 MHz) in order to study the profile evolution. The profiles are aligned in abs...

  20. Experimental study of energy harvesting in UHF band

    Science.gov (United States)

    Bernacki, Ł.; Gozdur, R.; Salamon, N.

    2016-04-01

    A huge progress of down-sizing technology together with trend of decreasing power consumption and, on the other hand, increasing efficiency of electronics give the opportunity to design and to implement the energy harvesters as main power sources. This paper refers to the energy that can be harvested from electromagnetic field in the unlicensed frequency bands. The paper contains description of the most popular techniques and transducers that can be applied in energy harvesting domain. The overview of current research and commercial solutions was performed for bands in ultra-high frequency range, which are unlicensed and where transmission is not limited by administrative arrangements. During the experiments with Powercast’s receiver, the same bands as sources of electromagnetic field were taken into account. This power source is used for conducting radio-communication process and excess energy could be used for powering the extra electronic circuits. The paper presents elaborated prototype of energy harvesting system and the measurements of power harvested in ultra-high frequency range. The evaluation of RF energy harvesters for powering ultra-low power (ULP) electronic devices was performed based on survey and results of the experiments.

  1. Medical professionalism: an experimental look at physicians’ Facebook profiles

    Directory of Open Access Journals (Sweden)

    Joseph W. Clyde

    2014-06-01

    Full Text Available Background: Use of social networking services (SNS is on the rise. While many users sign in for personal purposes, it is not uncommon for professionals to connect over SNSs with clients, students, and patients. Methods: The present study used an experimental approach to examine how medical doctors’ SNS profiles impacted potential patients’ impressions of professionalism. Participants (N=250 students were randomly assigned to view one of six Facebook profiles. Profiles were populated with 1 solely professional material, 2 personal material that was strictly healthy, or 3 personal material that included unhealthy behavior. Profiles portrayed a male or female physician resulting in a total of six experimental conditions. Medical professionalism was measured with the First Impressions of Medical Professionalism (FIMP scale, specifically developed for this study. Results: There was a large and statistically significant main effect for profile type, F(2, 250=54.77, p<0.001, ηp2=0.31. Post hoc tests indicated that personal profiles that contained healthy behavior were rated as most professional followed by profiles with strictly professional content. Personal unhealthy profiles were rated as least professional. Additionally, female profiles consistently received higher professionalism ratings across all three profile types [F(1, 250=5.04, p=0.026, ηp2=0.02]. Conclusion: Our results suggest that a physician's SNS profile affects a patient's perception of that physician's medical professionalism. A personal, healthy profile may augment a patient's perception of that physician's character virtues if the profile content upholds the decorum of the medical field.

  2. Quantitative operando visualization of the energy band depth profile in solar cells.

    Science.gov (United States)

    Chen, Qi; Mao, Lin; Li, Yaowen; Kong, Tao; Wu, Na; Ma, Changqi; Bai, Sai; Jin, Yizheng; Wu, Dan; Lu, Wei; Wang, Bing; Chen, Liwei

    2015-01-01

    The energy band alignment in solar cell devices is critically important because it largely governs elementary photovoltaic processes, such as the generation, separation, transport, recombination and collection of charge carriers. Despite the expenditure of considerable effort, the measurement of energy band depth profiles across multiple layers has been extremely challenging, especially for operando devices. Here we present direct visualization of the surface potential depth profile over the cross-sections of operando organic photovoltaic devices using scanning Kelvin probe microscopy. The convolution effect due to finite tip size and cantilever beam crosstalk has previously prohibited quantitative interpretation of scanning Kelvin probe microscopy-measured surface potential depth profiles. We develop a bias voltage-compensation method to address this critical problem and obtain quantitatively accurate measurements of the open-circuit voltage, built-in potential and electrode potential difference. PMID:26166580

  3. Quantitative operando visualization of the energy band depth profile in solar cells

    Science.gov (United States)

    Chen, Qi; Mao, Lin; Li, Yaowen; Kong, Tao; Wu, Na; Ma, Changqi; Bai, Sai; Jin, Yizheng; Wu, Dan; Lu, Wei; Wang, Bing; Chen, Liwei

    2015-07-01

    The energy band alignment in solar cell devices is critically important because it largely governs elementary photovoltaic processes, such as the generation, separation, transport, recombination and collection of charge carriers. Despite the expenditure of considerable effort, the measurement of energy band depth profiles across multiple layers has been extremely challenging, especially for operando devices. Here we present direct visualization of the surface potential depth profile over the cross-sections of operando organic photovoltaic devices using scanning Kelvin probe microscopy. The convolution effect due to finite tip size and cantilever beam crosstalk has previously prohibited quantitative interpretation of scanning Kelvin probe microscopy-measured surface potential depth profiles. We develop a bias voltage-compensation method to address this critical problem and obtain quantitatively accurate measurements of the open-circuit voltage, built-in potential and electrode potential difference.

  4. Band structure, cohesive properties, and Compton profile of γ- and α-cerium

    Science.gov (United States)

    Podloucky, R.; Glötzel, D.

    1983-03-01

    Recent Compton scattering experiments on the high-volume (γ) and low-volume (α) phases of fcc cerium and their interpretation in terms of the renormalized-free-atom model cast severe doubts on the promotional model of Pauling and Zachariasen for the γ-α transition. Stimulated by these results, we have extended a previous self-consistent local-density band-structure investigation to study the Compton profiles of γ- and α-cerium. For the band structure, Bloch functions, and their Fourier transforms we use the linear muffin-tin orbital method in the atomic-sphere approximation. We analyze the calculated Compton profiles in terms of band structure and local angular momentum character of the wave functions. The change in band structure and wave functions under compression (with approximately one electron per atom in the 4f band of both phases) accounts well for the observed change in the Compton profile. This provides further evidence against the promotional model in agreement with the analysis of Kornstädt et al. In addition, we study the cohesive energy of fcc cerium as a function of volume in the local-density approximation. For α-cerium in the 4f1(5d 6s)3 configuration we find a cohesive energy of 5.4 eV/atom in good agreement with experiment, whereas the "promotional" 4f0(5d 6s)4 state yields a binding energy of 0.6 eV/atom only. Therefore the fourth valence electron has to be a 4f electron, and α-cerium has to be regarded as an f-band metal.

  5. Calculation of isotopic profile during band displacement on ion exchange resins

    International Nuclear Information System (INIS)

    A method has been developed to calculate the isotopic profile during band displacement on ion exchange resins using computer simulation. Persoz had utilized this technique earlier for calculating the isotopic profile during band displacement as well as frontal analysis. The present report deals with a simplification of the method used by Persoz by reducing the number of variables and making certain approximations where the separation factor is not far from unity. Calculations were made for the typical case of boron isotope separation. The results obtained by the modified method were found to be in very good agreement with those obtained by using an exact equation, at the same time requiring conside--rably less computer time. (author)

  6. Experimentally minimized beam emittance from an L-band photoinjector

    Science.gov (United States)

    Krasilnikov, M.; Stephan, F.; Asova, G.; Grabosch, H.-J.; Groß, M.; Hakobyan, L.; Isaev, I.; Ivanisenko, Y.; Jachmann, L.; Khojoyan, M.; Klemz, G.; Köhler, W.; Mahgoub, M.; Malyutin, D.; Nozdrin, M.; Oppelt, A.; Otevrel, M.; Petrosyan, B.; Rimjaem, S.; Shapovalov, A.; Vashchenko, G.; Weidinger, S.; Wenndorff, R.; Flöttmann, K.; Hoffmann, M.; Lederer, S.; Schlarb, H.; Schreiber, S.; Templin, I.; Will, I.; Paramonov, V.; Richter, D.

    2012-10-01

    High brightness electron sources for linac based free-electron lasers (FELs) are being developed at the Photo Injector Test facility at DESY, Zeuthen site (PITZ). Production of electron bunches with extremely small transverse emittance is the focus of the PITZ scientific program. The photoinjector optimization in 2008-2009 for a bunch charge of 1, 0.5, 0.25, and 0.1 nC resulted in measured emittance values which are beyond the requirements of the European XFEL [S. Rimjaem , Nucl. Instrum. Methods Phys. Res., Sect. A 671, 62 (2012)NIMAER0168-900210.1016/j.nima.2011.12.101]. Several essential modifications were commissioned in 2010-2011 at PITZ, resulting in further improvement of the photoinjector performance. Significant improvement of the rf gun phase stability is a major contribution in the reduction of the measured transverse emittance. The old TESLA prototype booster was replaced by a new cut disk structure cavity. This allows acceleration of the electron beam to higher energies and supports much higher flexibility for stable booster operation as well as for longer rf pulses which is of vital importance especially for the emittance optimization of low charge bunches. The transverse phase space of the electron beam was optimized at PITZ for bunch charges in the range between 0.02 and 2 nC, where the quality of the beam measurements was preserved by utilizing long pulse train operation. The experimental optimization yielded worldwide unprecedented low normalized emittance beams in the whole charge range studied.

  7. Experimental characterization of negative refractive index material NRM at Ka band

    CERN Document Server

    Chatterjee, Sougata

    2016-01-01

    In this paper, we discuss the experimental characterization of a negative refractive material NRM at Ka band using LR labyrinth Ring and wire array WA. We describe in detail the the LR and wire array characterization separately, and after that the combined experimental results, for NRM are reported. The LRs analytical and simulation study is not new but design in Ka band and different experimental procedure for the characterization of the negative refractive index is the novelty of this paper. For performing a negative refractive index experiment we made prism of 150 Prism angle . We get enhanced transmittance of more than 20 dB from background, at a negative angle of refraction. The values of the negative refractive index in a band of about 1 G Hz around 31 GHz are retrieved from the experimental data.

  8. Preliminary experimental investigation of a dual-band relativistic backward wave oscillator with dual beams

    International Nuclear Information System (INIS)

    A dual-band relativistic backward wave oscillator with dual electron beams generating C-band and X-band microwaves is investigated experimentally. The frequencies, powers, and radiation patterns of the dual-band microwaves are measured. With the diode voltage of 657 kV and the total beam current of 14 kA guided by a magnetic field of about 1.7 T, the dual-band microwaves are generated with dominant frequencies of 4.58 and 8.30 GHz close to the results from the particle-in-cell simulation. The powers of the C-band and X-band microwaves are 520 and 113 MW, respectively. The effects of variations in the guiding magnetic field and diode voltage on the powers of the dual-band microwaves are presented and discussed. The radiation patterns of the dual-band microwaves from the radiating antenna are tested both corresponding to a TM01 mode and the independency of the operation processes of them is discussed.

  9. Experimental determination of conduction and valence bands of semiconductor nanoparticles using Kelvin probe force microscopy

    International Nuclear Information System (INIS)

    The ability to determine a semiconductor’s band edge positions is important for the design of new photocatalyst materials. In this paper, we introduced an experimental method based on Kelvin probe force microscopy to determine the conduction and valence band edge energies of semiconductor nanomaterials, which has rarely been demonstrated. We tested the method on six semiconductor nanoparticles (α-Fe2O3, CeO2, Al2O3, CuO, TiO2, and ZnO) with known electronic structures. The experimentally determined band edge positions for α-Fe2O3, Al2O3, and CuO well matched the literature values with no statistical difference. Except CeO2, all other metal oxides had a consistent upward bias in the experimental measurements of band edge positions because of the shielding effect of the adsorbed surface water layer. This experimental approach may outstand as a unique alternative way of probing the band edge energy positions of semiconductor materials to complement the current computational methods, which often find limitations in new synthetic or complex materials. Ultimately, this work provides scientific foundation for developing experimental tools to probe nanoscale electronic properties of photocatalytic materials, which will drive breakthroughs in the design of novel photocatalytic systems and advance the fundamental understanding of material properties.

  10. Experimental observations of shear band nucleation and propagation in a bulk metallic glass using wedge-like cylindrical indentation

    Science.gov (United States)

    Antoniou, Antonia Maki

    2006-12-01

    Bulk metallic glasses (BMGs), or amorphous metal alloys, have a unique combination of properties such as high strength, large elastic strain limit (up to 2%), corrosion resistance and formability. These unique properties make them candidates for precision mechanical elements, hinge supports, contact surfaces as well as miniaturized systems (MEMS). However, their limited ductility hinders further realizations of their industrial potential. Under uniaxial tension tests, metallic glass fails in a brittle manner with unstable propagation of a single shear band. There is a need to understand the conditions for shear band nucleation and propagation in order to achieve a superior material system with adequate toughness to ensure in-service reliability. This dissertation focuses on understanding the nucleation and propagation mechanisms of shear bands in BMGs under constrained deformation. The nature of the work is primarily experimental with integrated finite element simulations to elucidate the observed trends. Wedge indentation with a circular profile of different radii is used to provide a stable loading path for in situ monitoring of shear band nucleation, propagation in Vitreloy-1. Detailed analyses of the in-plane finite deformation fields are carried out using digital image correlation. The incremental surface analysis showed that multiple shear bands are developed beneath the indenter. The observed pattern closely follow the traces of slip line field for a pressure sensitive material. The first shear bands initiate in the bulk beneath the indenter when a critical level of mean pressure is achieved. Two distinct shear band patterns are developed, that conform to either the alpha or beta lines for each sector. The deformation zones developed under indenters with different radii were found to be self-similar. The evolution of shear bands beneath the indenter is also characterized into two different categories. A set of primary bands is identified to evolve with the

  11. An experimental study for the Cross Domain Author Profiling classification

    OpenAIRE

    Garciarena Ucelay, María José; Villegas, María Paula; Cagnina, Leticia; ERRECALDE, MARCELO LUIS

    2015-01-01

    Author Profiling is the task of predicting characteristics of the author of a text, such as age, gender, personality, native language, etc. This is a task of growing importance due to the potential applications in security, crime detection and marketing, among others. An interesting point is to study the robustness of a classifier when it is trained with a dataset and tested with others containing different characteristics. Commonly this is called cross domain experimentation. Although differ...

  12. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  13. Constraining CloudSat-based snowfall profiles using surface observations and C-band ground radar

    Science.gov (United States)

    Turk, F. Joseph; Park, Kyung-Won; Haddad, Ziad S.; Rodriguez, Peter; Hudak, David R.

    2011-12-01

    The CloudSat Precipitation Radar, launched in 2006, provides vertical profiles of W-band (94 GHz) reflectivity and is sensitive to falling snow through all but the most intense precipitating cloud structures. Precipitation retrievals of falling snow are affected by a wide diversity of factors describing the medium, such as snow particle shape, size, and composition, which in turn are controlled by ambient factors including the environmental temperature and humidity. Because satellite-based radiometric sounders such as the Microwave Humidity Sounder (MHS) operate without the benefit of coordinated space radar observations, microphysical descriptions of the snow particle medium derived from CloudSat or other radar observations are beneficial to passive microwave (PMW) radiometer-only snowfall retrieval methods. At the coarse scale of these PMW observations, the radiative signal due to the snow is relatively weak compared to the contributions from the atmosphere and the land surface emissivity. Using the C-band (5 GHz) polarization-agile King City radar (WKR) operated by Environment Canada, we examined the vertical structure of winter precipitation events from coordinated overpasses of CloudSat and NOAA 18 (MHS). Two-dimensional video disdrometer observations are used to limit (constrain) the range of the drop-size distribution parameters that are provided through a priori databases to dual-frequency (C/W-band) radar retrieval. Bayesian retrievals using the constrained database produce water content profiles that more closely replicate the observed radar reflectivity profiles and transition smoothly between the single-frequency (CloudSat only) and dual-frequency regions.

  14. Trap profiling at nanocavity bands in silicon wafers by means of capacitance-voltage measurements

    CERN Document Server

    Auriac, N

    2002-01-01

    Nanocavities are formed by He sup + -and H sup + -ion implantation in silicon single crystals, at the projected range R sub p , after post-implantation annealing. The present paper deals with the characterization of deep trap levels associated with such defects. P-type silicon single crystals were implanted using He sup + -and H sup + -ion beams, at an energy of 250 keV and to a dose of 3 x 10 sup 1 sup 6 cm sup - sup 2. Capacitance-voltage (C-V) profiling and deep-level transient spectroscopy (DLTS) techniques were used to determine the density profile and the energy levels of deep traps in the gap. In implanted and post-annealed samples a quasi-triangular profile of the space charge is revealed around R sub p by C-V profiling, and the space charge density reaches 10 sup 1 sup 6 cm sup - sup 3. DLTS suggests that trap levels are located at 0.4 eV above the valence band, with a maximum density around 10 sup 1 sup 5 cm sup - sup 3 at R sub p. The sign and distribution of the space charge for depletion in He su...

  15. Preliminary experimental investigation of a complex dual-band high power microwave source

    International Nuclear Information System (INIS)

    In order to promote the power conversion efficiency of a magnetically insulated transmission line oscillator (MILO) and obtain microwaves in dual bands, an axially extracted C-band virtual cathode oscillator (VCO) with multiple resonant cavities is introduced to partially utilize the load current of an S-band MILO. The formed novel dual-band high power microwave source called MILO and VCO is investigated with simulation and experimentally. A dual-band radiation antenna is designed to effectively radiate microwaves generated by the MILO and the VCO, respectively, while avoiding them being influenced by the microwave reflection and diffraction. The preliminary experimental results measured by the dual-band diagnostic system show that both the MILO and the VCO operate normally under repeated shots. A microwave of 2.1 GHz, 1.70 GW is generated from the MILO and a 0.37 GW microwave at frequencies of 4.1 GHz and 3.8 GHz is generated from the VCO under the condition of about 440 kV and 35 kA. Compared with a single MILO (10.6%), a MILO and VCO achieves higher total power and efficiency (13.4%) in both S and C bands, indicating that the load current of the MILO partially couples into the beam-wave interaction in the VCO and then contributes to the output microwaves. However, more works are needed regarding the spectrum purification of the VCO and promotion of the output power of both the MILO and the VCO

  16. Preliminary experimental investigation of a complex dual-band high power microwave source

    Science.gov (United States)

    Zhang, Xiaoping; Li, Yangmei; Li, Zhiqiang; Zhong, Huihuang; Qian, Baoliang

    2015-10-01

    In order to promote the power conversion efficiency of a magnetically insulated transmission line oscillator (MILO) and obtain microwaves in dual bands, an axially extracted C-band virtual cathode oscillator (VCO) with multiple resonant cavities is introduced to partially utilize the load current of an S-band MILO. The formed novel dual-band high power microwave source called MILO and VCO is investigated with simulation and experimentally. A dual-band radiation antenna is designed to effectively radiate microwaves generated by the MILO and the VCO, respectively, while avoiding them being influenced by the microwave reflection and diffraction. The preliminary experimental results measured by the dual-band diagnostic system show that both the MILO and the VCO operate normally under repeated shots. A microwave of 2.1 GHz, 1.70 GW is generated from the MILO and a 0.37 GW microwave at frequencies of 4.1 GHz and 3.8 GHz is generated from the VCO under the condition of about 440 kV and 35 kA. Compared with a single MILO (10.6%), a MILO and VCO achieves higher total power and efficiency (13.4%) in both S and C bands, indicating that the load current of the MILO partially couples into the beam-wave interaction in the VCO and then contributes to the output microwaves. However, more works are needed regarding the spectrum purification of the VCO and promotion of the output power of both the MILO and the VCO.

  17. Preliminary experimental investigation of a complex dual-band high power microwave source

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaoping, E-mail: zhangxiaoping@nudt.edu.cn; Li, Yangmei; Li, Zhiqiang; Zhong, Huihuang; Qian, Baoliang [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2015-10-15

    In order to promote the power conversion efficiency of a magnetically insulated transmission line oscillator (MILO) and obtain microwaves in dual bands, an axially extracted C-band virtual cathode oscillator (VCO) with multiple resonant cavities is introduced to partially utilize the load current of an S-band MILO. The formed novel dual-band high power microwave source called MILO and VCO is investigated with simulation and experimentally. A dual-band radiation antenna is designed to effectively radiate microwaves generated by the MILO and the VCO, respectively, while avoiding them being influenced by the microwave reflection and diffraction. The preliminary experimental results measured by the dual-band diagnostic system show that both the MILO and the VCO operate normally under repeated shots. A microwave of 2.1 GHz, 1.70 GW is generated from the MILO and a 0.37 GW microwave at frequencies of 4.1 GHz and 3.8 GHz is generated from the VCO under the condition of about 440 kV and 35 kA. Compared with a single MILO (10.6%), a MILO and VCO achieves higher total power and efficiency (13.4%) in both S and C bands, indicating that the load current of the MILO partially couples into the beam-wave interaction in the VCO and then contributes to the output microwaves. However, more works are needed regarding the spectrum purification of the VCO and promotion of the output power of both the MILO and the VCO.

  18. Coral transcriptome and bacterial community profiles reveal distinct Yellow Band Disease states in Orbicella faveolata

    KAUST Repository

    Closek, Collin J.

    2014-06-20

    Coral diseases impact reefs globally. Although we continue to describe diseases, little is known about the etiology or progression of even the most common cases. To examine a spectrum of coral health and determine factors of disease progression we examined Orbicella faveolata exhibiting signs of Yellow Band Disease (YBD), a widespread condition in the Caribbean. We used a novel combined approach to assess three members of the coral holobiont: the coral-host, associated Symbiodinium algae, and bacteria. We profiled three conditions: (1) healthy-appearing colonies (HH), (2) healthy-appearing tissue on diseased colonies (HD), and (3) diseased lesion (DD). Restriction fragment length polymorphism analysis revealed health state-specific diversity in Symbiodinium clade associations. 16S ribosomal RNA gene microarrays (PhyloChips) and O. faveolata complimentary DNA microarrays revealed the bacterial community structure and host transcriptional response, respectively. A distinct bacterial community structure marked each health state. Diseased samples were associated with two to three times more bacterial diversity. HD samples had the highest bacterial richness, which included components associated with HH and DD, as well as additional unique families. The host transcriptome under YBD revealed a reduced cellular expression of defense- and metabolism-related processes, while the neighboring HD condition exhibited an intermediate expression profile. Although HD tissue appeared visibly healthy, the microbial communities and gene expression profiles were distinct. HD should be regarded as an additional (intermediate) state of disease, which is important for understanding the progression of YBD. © 2014 International Society for Microbial Ecology. All rights reserved.

  19. Aerosol profile information from high resolution oxygen A-Band measurements from space

    Directory of Open Access Journals (Sweden)

    A. Geddes

    2014-06-01

    Full Text Available Aerosols are an important factor of the Earth climatic system and they play a key role for air quality and public health. Observations of the oxygen A-Band at 760 nm can provide information on the vertical distribution of aerosols from passive satellite sensors, that can be of great interest for operational monitoring applications with high coverage if the aerosol information is obtained with sufficient precision, accuracy and vertical resolution. To address this issue, retrieval simulations of the aerosol vertical profile retrieval from O2 A Band observations by GOSAT, the upcoming OCO-2 and Sentinel 5-P mission and the proposed CarbonSat mission have been carried out. Precise retrievals of AOD within the boundary layer were found to favour low resolution, high SNR instruments such as Sentinel-5 P, whereas higher resolution instruments such as OCO-2 showed greater performance at higher altitudes and in information content above the boundary layer. Accurate retrievals of the AOD in the 0–2 km range appears difficult from all studied instruments and the retrieval errors typically exceed a value of 0.05. Constraining the surface albedo is a promising and effective way of improving the retrieval of aerosol, but the required level of a priori knowledge is very high. Due to the limited information content of the aerosol profile retrieval, the use of a parameterised aerosol distribution has been assessed and we show that the AOD and height of an aerosol layer can be retrieved well if the aerosol layer is uplifted to the free troposphere but errors are often large for aerosol layers in the boundary layer. Additional errors will be introduced by incorrect assumptions on surface pressure and aerosol type which can both bias retrieved AOD and height by up to 40%. We conclude the aerosol profile retrievals from O2 A Band using existing or upcoming satellite sensors will only provide limited information on aerosols in the boundary layer but such

  20. Experimental study of an X-band phase-locked relativistic backward wave oscillator

    Science.gov (United States)

    Wu, Y.; Li, Z. H.; Xu, Z.

    2015-11-01

    To achieve high power microwave combined with high frequency band, an X-band phase-locked relativistic backward wave oscillator (RBWO) is proposed and investigated theoretically and experimentally using a modulated electron beam. In the device, an overmoded input cavity and a buncher cavity are employed to premodulate the electron beam. Particle-in-cell simulation shows that an input power of 90 kW is sufficient to lock the frequency and phase of 1.5 GW output microwave with the locking bandwidth of 60 MHz. Moreover, phase and frequency locking of an RBWO has been accomplished experimentally with an output power of 1.5 GW. The fluctuation of the relative phase difference between output microwave and input RF signal is less than ±20° with the locking duration of about 50 ns. The input RF power required to lock the oscillator is only 90 kW.

  1. Experimental study of an X-band phase-locked relativistic backward wave oscillator

    International Nuclear Information System (INIS)

    To achieve high power microwave combined with high frequency band, an X-band phase-locked relativistic backward wave oscillator (RBWO) is proposed and investigated theoretically and experimentally using a modulated electron beam. In the device, an overmoded input cavity and a buncher cavity are employed to premodulate the electron beam. Particle-in-cell simulation shows that an input power of 90 kW is sufficient to lock the frequency and phase of 1.5 GW output microwave with the locking bandwidth of 60 MHz. Moreover, phase and frequency locking of an RBWO has been accomplished experimentally with an output power of 1.5 GW. The fluctuation of the relative phase difference between output microwave and input RF signal is less than ±20° with the locking duration of about 50 ns. The input RF power required to lock the oscillator is only 90 kW

  2. High resolution dopant profiling in the SEM, image widths and surface band-bending

    International Nuclear Information System (INIS)

    To study the mechanisms of dopant contrast in secondary electron (SE) imaging in the SEM, we have measured the image widths of a series of thin p-doped layers in Si, from 1 nm upwards. We have used computer modelling to simulate the effects of surface band-bending due to a realistic density of surface states on the Si, and we have also calculated the magnitude of the external patch fields. We have found a good correlation between the intensity widths and slopes of experimentally measured SE images of thin p-doped layers and the calculated widths and slopes of the energy distributions across these layers at a depth of 5-10 nm below the surface. This is consistent with the mean escape depth of SEs in Si being about 7 nm. We conclude that doping contrast in the SEM is mainly a function of bulk built-in voltages modified by surface band-bending effects within about 5-10 nm of the surface.

  3. Experimental - theoretical study of axially compressed cold formed steel profiles

    Directory of Open Access Journals (Sweden)

    Bešević Miroslav

    2011-01-01

    Full Text Available Analysis of axially compressed steel members made of cold formed profiles presented in this paper was conducted through both experimental and numerical methods. Numerical analysis was conducted by means of "PAK" finite element software designed for nonlinear static and dynamic analysis of structures. Results of numerical analysis included ultimate bearing capacity with corresponding middle section force-deflection graphs and buckling curves. Extensive experimental investigation were also concentrated on determination of bearing capacity and buckling curves. Experiments were conducted on five series with six specimens each for slenderness values of 50, 70, 90, 110 and 120. Compressed simply supported members were analyzed on Amsler Spherical pin support with unique electronical equipment and software. Besides determination of forcedeflection curves, strains were measured in 18 or 12 cross sections along the height of the members. Analysis included comparisons with results obtained by different authors in this field recently published in international journals. Special attention was dedicated to experiments conducted on high strength and stainless steel members.

  4. Experimental research on Ku-band magnetically insulated transmission line oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Tao; Zhang, Jiande; He, Juntao; Li, Zhiqiang; Ling, Junpu [College of Optoelectric Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

    2015-10-15

    An improved Ku-band magnetically insulated transmission line oscillator is proposed and investigated experimentally. In the particle-in-cell simulation, the Ku-band MILO generates the microwave with a power of 1.62 GW and a frequency of 13 GHz at the input voltage of 474 kV. The device is fabricated based on the simulation results, and an experiment system is designed. In the preliminary experiments, output microwave with frequency of 13.02 GHz, power of 150 MW, and pulse width of 17 ns is generated, under the diode voltage of 450 kV. Analysis on the experiment results shows that plasma produced due to the large current hitting to the outside of the collection tank is the essential cause for the low amplitude of the microwave power and short pulse width.

  5. Experimental research on Ku-band magnetically insulated transmission line oscillator

    Science.gov (United States)

    Jiang, Tao; Zhang, Jiande; He, Juntao; Li, Zhiqiang; Ling, Junpu

    2015-10-01

    An improved Ku-band magnetically insulated transmission line oscillator is proposed and investigated experimentally. In the particle-in-cell simulation, the Ku-band MILO generates the microwave with a power of 1.62 GW and a frequency of 13 GHz at the input voltage of 474 kV. The device is fabricated based on the simulation results, and an experiment system is designed. In the preliminary experiments, output microwave with frequency of 13.02 GHz, power of 150 MW, and pulse width of 17 ns is generated, under the diode voltage of 450 kV. Analysis on the experiment results shows that plasma produced due to the large current hitting to the outside of the collection tank is the essential cause for the low amplitude of the microwave power and short pulse width.

  6. Experimental research on Ku-band magnetically insulated transmission line oscillator

    International Nuclear Information System (INIS)

    An improved Ku-band magnetically insulated transmission line oscillator is proposed and investigated experimentally. In the particle-in-cell simulation, the Ku-band MILO generates the microwave with a power of 1.62 GW and a frequency of 13 GHz at the input voltage of 474 kV. The device is fabricated based on the simulation results, and an experiment system is designed. In the preliminary experiments, output microwave with frequency of 13.02 GHz, power of 150 MW, and pulse width of 17 ns is generated, under the diode voltage of 450 kV. Analysis on the experiment results shows that plasma produced due to the large current hitting to the outside of the collection tank is the essential cause for the low amplitude of the microwave power and short pulse width

  7. AirMOSS P-Band Radar Retrieval of Subcanopy Soil Moisture Profile

    Science.gov (United States)

    Tabatabaeenejad, A.; Burgin, M. S.; Duan, X.; Moghaddam, M.

    2013-12-01

    Knowledge of soil moisture, as a key variable of the Earth system, plays an important role in our under-standing of the global water, energy, and carbon cycles. The importance of such knowledge has led NASA to fund missions such as Soil Moisture Active and Passive (SMAP) and Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS). The AirMOSS mission seeks to improve the estimates of the North American Net Ecosystem Exchange (NEE) by providing high-resolution observations of the root zone soil moisture (RZSM) over regions representative of the major North American biomes. AirMOSS flies a P-band SAR to penetrate vegetation and into the root zone to provide estimates of RZSM. The flights cover areas containing flux tower sites in regions from the boreal forests in Saskatchewan, Canada, to the tropical forests in La Selva, Costa Rica. The radar snapshots are used to generate estimates of RZSM via inversion of a scattering model of vegetation overlying soils with variable moisture profiles. These retrievals will be used to generate a time record of RZSM, which will be integrated with an ecosystem demography model in order to estimate the respiration and photosynthesis carbon fluxes. The aim of this work is the retrieval of the moisture profile over AirMOSS sites using the collected P-band radar data. We have integrated layered-soil scattering models into a forest scattering model; for the backscattering from ground and for the trunk-ground double-bounce mechanism, we have used a layered small perturbation method and a coherent scattering model of layered soil, respectively. To estimate the soil moisture profile, we represent it as a second-order polynomial in the form of az2 + bz + c, where z is the depth and a, b, and c are the coefficients to be retrieved from radar measurements. When retrieved, these coefficients give us the soil moisture up to a prescribed depth of validity. To estimate the unknown coefficients of the polynomial, we use simulated

  8. K-band EPR dosimetry: small-field beam profile determination with miniature alanine dosimeter

    International Nuclear Information System (INIS)

    The use of small-size alanine dosimeters presents a challenge because the signal intensity is less than the spectrometer sensitivity. K-band (24 GHz) EPR spectrometer seems to be a good compromise between size and sensitivity of the sample. Miniature alanine pellets were evaluated for small-field radiation dosimetry. Dosimeters of DL-alanine/PVC with dimensions of 1.5 mm diameter and 2.5 mm length with 5 mg mass were developed. These dosimeters were irradiated with 10 MV X-rays in the dose range 0.05-60 Gy and the first harmonic (1 h) spectra were recorded. Microwave power, frequency and amplitude of modulation were optimized to obtain the best signal-to-noise ratio (S/N). For beam profile determination, a group of 25 dosimeters were placed in an acrylic device with dimensions of (7.5x2.5x1) cm3 and irradiated with a (3x3) cm2 10 MV X-rays beam field size. The dose at the central region of the beam was 20 Gy at a depth of 2.2 cm (build up for acrylic). The acrylic device was oriented perpendicular to the beam axis and to the gantry rotation axis. For the purposes of comparison of the spatial resolution, the beam profile was also determined with a radiographic film and 2 mm aperture optical densitometer; in this case the dose was 1 cGy. The results showed a similar spatial resolution for both types of dosimeters. The dispersion in dose reading was larger for alanine in comparison with the film, but alanine dosimeters can be read faster and more directly than film over a wide dose range

  9. Experimental results of a high efficiency high power X-band gyroklystron

    International Nuclear Information System (INIS)

    In order to build a multi-TeV Next Generation Linear Collider with a reasonable length, a high accelerating gradient and high RF frequency are required. A gyroklystron in the frequency range of 30 GHz is considered to be one of the most promising RF sources. Pulsed gyrotron amplifiers have record performance at frequencies significantly above X-Band, e.g., output peak powers exceeding 30 MW were achieved with an efficiency near 30% at the frequency of 19.76 GHz at the University of Maryland. A new first harmonic coaxial three-cavity gyroklystron in X-Band has been built and tested to verify operation of the test bed. This microwave circuit has demonstrated the high power and high efficiency of the system configuration with the ultimate goal of extending the design of coaxial gyroklystrons to 17.1--34.2 GHz. The designed operating frequency is 8.568 GHz with a pulse width of 2 micros and a maximum repetition rate of 2 Hz. The operating beam voltage and beam current for the fundamental circuit are 470 kV and 500 A, respectively. An X-Band mechanically-tunable coaxial magnetron (8.5--9.6 GHz, 2 micros) provides a maximum input signal of 150 kW. The preliminary experimental results showed that an output peak power of 85 MW with an efficiency over 35% can be obtained from this coaxial three-cavity gyroklystron. The details of the design parameters and experimental results of this X-Band gyroklystron will be presented

  10. Experimental results of a high efficiency high power X-band gyroklystron

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J.; Lawson, W.; Hogan, B.; Xu, X.; Castle, M.; Calame, J.P.; Granatstein, V.L.; Reiser, M. [Univ. of Maryland, College Park, MD (United States)

    1998-12-31

    In order to build a multi-TeV Next Generation Linear Collider with a reasonable length, a high accelerating gradient and high RF frequency are required. A gyroklystron in the frequency range of 30 GHz is considered to be one of the most promising RF sources. Pulsed gyrotron amplifiers have record performance at frequencies significantly above X-Band, e.g., output peak powers exceeding 30 MW were achieved with an efficiency near 30% at the frequency of 19.76 GHz at the University of Maryland. A new first harmonic coaxial three-cavity gyroklystron in X-Band has been built and tested to verify operation of the test bed. This microwave circuit has demonstrated the high power and high efficiency of the system configuration with the ultimate goal of extending the design of coaxial gyroklystrons to 17.1--34.2 GHz. The designed operating frequency is 8.568 GHz with a pulse width of 2 {micro}s and a maximum repetition rate of 2 Hz. The operating beam voltage and beam current for the fundamental circuit are 470 kV and 500 A, respectively. An X-Band mechanically-tunable coaxial magnetron (8.5--9.6 GHz, 2 {micro}s) provides a maximum input signal of 150 kW. The preliminary experimental results showed that an output peak power of 85 MW with an efficiency over 35% can be obtained from this coaxial three-cavity gyroklystron. The details of the design parameters and experimental results of this X-Band gyroklystron will be presented.

  11. A sensitivity study on the retrieval of aerosol vertical profiles using the oxygen A-band

    Science.gov (United States)

    Fedele Colosimo, Santo; Natraj, Vijay; Sander, Stanley P.; Stutz, Jochen

    2016-04-01

    Atmospheric absorption in the O2 A-band (12 950-13 200 cm-1) offers a unique opportunity to retrieve aerosol extinction profiles from space-borne measurements due to the large dynamic range of optical thickness in that spectral region. Absorptions in strong O2 lines are saturated; therefore, any radiance measured in these lines originates from scattering in the upper part of the atmosphere. Outside of O2 lines, or in weak lines, the atmospheric column absorption is small, and light penetrates to lower atmospheric layers, allowing for the quantification of aerosols and other scatterers near the surface.While the principle of aerosol profile retrieval using O2 A-band absorption from space is well-known, a thorough quantification of the information content, i.e., the amount of vertical profile information that can be obtained, and the dependence of the information content on the spectral resolution of the measurements, has not been thoroughly conducted. Here, we use the linearized vector radiative transfer model VLIDORT to perform spectrally resolved simulations of atmospheric radiation in the O2 A-band for four different aerosol extinction profile scenarios: urban (urban-rural areas), highly polluted (megacity areas with large aerosol extinction), elevated layer (identifying elevated plumes, for example for biomass burning) and low extinction (representative of small aerosol extinction, such as vegetated, marine and arctic areas). The high-resolution radiances emerging from the top of the atmosphere measurements are degraded to different spectral resolutions, simulating spectrometers with different resolving powers. We use optimal estimation theory to quantify the information content in the aerosol profile retrieval with respect to different aerosol parameters and instrument spectral resolutions. The simulations show that better spectral resolution generally leads to an increase in the total amount of information that can be retrieved, with the number of degrees of

  12. The K-band intensity profile of R Leonis probed by VLTI/VINCI

    CERN Document Server

    Fedele, D; Paresce, F; Scholz, M; Wood, P R; Ciroi, S

    2004-01-01

    We present near-infrared K-band interferometric measurements of the Mira star R Leonis obtained in April 2001 and January 2002 with the VLTI, the commissioning instrument VINCI, and the two test siderostats. These epochs correspond to near-maximum stellar variability phases $\\sim$ 0.08 and $\\sim$ 1.02 (one cycle later), respectively. The April 2001 data cover a range of spatial frequencies (31--35 cycles/arcsecond) within the first lobe of the visibility function. These measurements indicate a center-to-limb intensity variation (CLV) that is clearly different from a uniform disk (UD) intensity profile. We show that these measured visibility values are consistent with predictions from recent self-excited dynamic Mira model atmospheres that include molecular shells close to continuum-forming layers. We derive high-precision Rosseland diameters of 28.5 +/- 0.4 mas and 26.2 +/- 0.8 mas for the April 2001 and January 2002 data, respectively. Together with literature estimates of the distance and the bolometric flu...

  13. A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Hung-Wen; Lee, Ki Ha; Becker, Alex

    2004-12-17

    A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify this new approach. A set of the impedance difference data acquired at the University of California's Richmond Field Station compares reasonably well with simulation results based on a model obtained with the resistivity method and in situ TDR (time domain reflectometry)measurements.

  14. Dual-band low profile antennas for body-centric communications

    NARCIS (Netherlands)

    Chandran, A.R.; Scanlon, W.G.

    2010-01-01

    Dual-band operation is highly desirable for wearable devices that need to connect with a range of wireless systems. We present a series of microstrip-line fed, dual-band compact patch antennas designed to operate in the common 2.45 GHz and 5.8 GHz bands for body-centric communications. All of the de

  15. Experimental verification of stress-wave bands and negative phase velocity in layered media

    Directory of Open Access Journals (Sweden)

    Amirkhizi Alireza V.

    2011-01-01

    Full Text Available Based on a robust numerical method for calculation of band structure for stress-waves in heterogeneous media, a layered composite was designed and fabricated. It is shown that in the second pass band of this simple 2-phase layered structure, the direction of the energy flow is opposite that of the phase velocity. The ultrasonic stress-wave transmission through multiple thicknesses of this structure was studied experimentally and various quantities, such as band structure, phase velocity, group velocity, and a representation of the velocity of energy propagation were measured and compared with numerical predictions. The numerical calculations are based on hybrid (mixed min-max variational principles presented previously by Nemat-Nasser and coworkers. In the cases where a closed form solution exists, the numerical results of this method agree very accurately with the results of the exact solution. Furthermore, the computational efficiency of the mixed variational method renders it an excellent tool for design and analysis of stress-wave propagation in heterogeneous media.

  16. Experimental characterization of a hybrid fiber-wireless transmission link in the 75 to 110 GHz band

    DEFF Research Database (Denmark)

    Pang, Xiaodan; Yu, Xianbin; Zhao, Ying; Deng, Lei; Zibar, Darko; Tafur Monroy, Idelfonso

    2012-01-01

    We present a detailed experimental investigation of a hybrid optical-fiber wireless communication system operating at the 75 to 110 GHz (W-band) for meeting the emerging demands in short-range wireless applications. Measured W-band wireless channel properties such as channel loss, frequency...

  17. Experimental and theoretical investigation of anomalous behavior in rotational bands at high spin

    International Nuclear Information System (INIS)

    High spin states of the barium nuclei have been investigated via the 114Cd(16O,4n)126Ba, 120Sn(12C,4n)128Ba and 124Sn(12C,4n)132Ba reactions. The even spin positive parity yrast band in 126Ba has been excited up to the 16+, and possibly the 18+ state. In addition, another strongly excited band was excited with spins and parities: 7-, 9-, 11-, 13- and 15-. In 128Ba, the even spin positive parity band has been excited up to the 12+ state. Backbending seems to begin at the 12+ state. Two-quasiparticles-plus-rotor bandmixing calculations have been performed in order to explain the backbending and the anomalous negative parity bands observed in 126128Ba and several other nuclei. The test case of 68156Er88 was studied in detail. Good agreement with experimental excitation energies was obtained. The E2 transition rates between the negative parity yrast states were estimated for 156Er. Strongly enhanced rates are found within the states of odd spin, and within the state of even spin. The values of the g-factors were also estimated for the two-quasineutron yrast states in 156Er, showing considerable deviations from the rotational values. The calculation was applied, with very similar results to 56126Ba70. Reasonable fits to the excitation energies were obtained. The case of 46104Pd58 was considered, and very similar results were obtained. The nucleus 80192Hg112 was also studied. No reasonable fit was obtained for the negative parity states. The above evidence suggests that decoupling effects are responsible for the anomalous high spin behavior of the nuclei considered

  18. Gene expression profiling and endothelin in acute experimental pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Helieh S Oz; Ying Lu; Louis P Vera-Portocarrero; Pei Ge; Ada Silos-Santiago; Karin N Westlund

    2012-01-01

    AIM:To analyze gene expression profiles in an experimental pancreatitis and provide functional reversal of hypersensitivity with candidate gene endothelin-1 antagonists.METHODS:Dibutyltin dichloride (DBTC) is a chemical used as a polyvinyl carbonate stabilizer/catalyzer,biocide in agriculture,antifouling agent in paint and fabric.DBTC induces an acute pancreatitis flare through generation of reactive oxygen species.Lewis-inbred rats received a single i.v.injection with either DBTC or vehicle.Spinal cord and dorsal root ganglia (DRG) were taken at the peak of inflammation and processed for transcriptional profiling with a cDNA microarray biased for rat brain-specific genes.In a second study,groups of animals with DBTC-induced pancreatitis were treated with endothelin (ET) receptor antagonists [ET-A (BQ123) and ET-B BQ788)].Spontaneous pain related mechanical and thermal hypersensitivity were measured.Immunohistochemical analysis was performed using anti-ET-A and ET-B antibodies on sections from pancreatic tissues and DRG of the T10-12 spinal segments.RESULTS:Animals developed acute pancreatic inflammation persisting 7-10 d as confirmed by pathological studies (edema in parenchyma,loss of pancreatic architecture and islets,infiltration of inflammatory cells,neutrophil and mononuclear cells,degeneration,vacuolization and necrosis of acinar cells) and the painrelated behaviors (cutaneous secondary mechanical and thermal hypersensitivity).Gene expression profile was different in the spinal cord from animals with pancreatitis compared to the vehicle control group.Over 260 up-regulated and 60 down-regulated unique genes could be classified into 8 functional gene families:circulatory/acute phase/immunomodulatory; extracellular matrix; structural; channel/receptor/transporter; signaling transduction; transcription/translation-related; antioxidants/chaperones/heat shock; pancreatic and other enzymes.ET-1 was among the 52 candidate genes upregulated greater than 2-fold in

  19. Experimental investigation of photonic band gap in one-dimensional photonic crystals with metamaterials

    International Nuclear Information System (INIS)

    Composite right/left-handed transmission lines with lumped element series capacitors and shunt inductors are used to experimentally realize the one-dimensional photonic crystals composed of single-negative metamaterials. The simulated and experimental results show that a special photonic band gap corresponding to zero-effective-phase (zero-φeff) may appear in the microwave regime. In contrast to the Bragg gap, by changing the length ratio of the two component materials, the width and depth of the zero-φeff gap can be conveniently adjusted while keeping the center frequency constant. Furthermore, the zero-φeff gap vanishes when both the phase-matching and impedance-matching conditions are satisfied simultaneously. These transmission line structures provide a good way for realizing microwave devices based on the zero-φeff gap. -- Highlights: ► 1D photonic crystals with metamaterials were investigated experimentally. ► Both Bragg gap and zero-φeff gap were observed in the microwave regime. ► The width and depth of the zero-φeff gap were experimentally adjusted. ► Zero-φeff gap was observed to be close when two match conditions were satisfied.

  20. Experimental Study Of X-band Dielectric-loaded Accelerating Structures

    CERN Document Server

    Jing, C

    2005-01-01

    A joint Argonne National Laboratory (ANL)/Naval Research Laboratory (NRL) program is under way to investigate X- band dielectric-loaded accelerating (DLA) structures, using high-power 11.424GHz radiation from the NRL Magnicon facility. As an advanced accelerator concepts, the dielectric-loaded accelerator offers the potential for a simple, inexpensive alternative to high-gradient RF linear accelerators. In this thesis, a comprehensive account of X-band DLA structure design, including theoretical calculation, numerical simulation, fabrication and testing, is presented in detail. Two types of loading dielectrics, alumina and MgxCa1−xTiO 3 (MCT), are investigated. For alumina (with dielectric constant 9.4), no RF breakdown has been observed up to 5 MW of drive power (equivalent to 8MV/m accelerating gradient) in the high power RF testing at NRL, but multipactor was observed to absorb a large fraction of the incident microwave power. Experimental results on suppression of multipactor using TiN coating o...

  1. The experimental investigation of the X-band transit-time tube oscillator

    CERN Document Server

    MaQiaoSheng; Fan Zhi Kai; Hu Hai Ying; LiuQingXiang; Su Chang

    2002-01-01

    The experimental investigation of X-band transit-time tube oscillator on the accelerator Sinus-700 is described. The accelerator is adjusted so that it can work stably; some parameters which influence the operation of the microwave device are adjusted so that the appropriate values of the parameters are obtained. The appropriate values of the parameters are described as follow: the length of the 1/4 wavelength stand equals 8 mm, the strength of the magnetic field 1.75 T, the voltage of the diode 700 kV and the shape of the cathode is annular. As a result, the microwave frequency is 9.18 GHz, the microwave power 1.5 GW, the pulse width 26 ns and the power conversion efficiency 31%

  2. New materials for intermediate band photovoltaic cells. A theoretical and experimental approach

    OpenAIRE

    Wahnón Benarroch, Perla; Palacios Clemente, Pablo; Aguilera Bonet, Irene; Seminóvski Pérez, Yohanna; Conesa, Jose Carlos; Lucena, Raquel

    2010-01-01

    Density functional theory calculations of certain transition-metal doped semiconductors show a partially occupied relatively narrow band located between valence band and conduction band. These novel systems, containing the metallic band, are called intermediate-band materials. They have enhanced optoelectronic properties which allow an increase in solar energy conversion efficiency of conventional solar cells. We previously proposed III-V, chalcopyrite and sulfide derived compounds show...

  3. Experimental investigation of the 0{sub 2}{sup +} band in {sup 154}Sm as a β-vibrational band

    Energy Technology Data Exchange (ETDEWEB)

    Smallcombe, J., E-mail: james.smallcombe@outlook.com [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Davies, P.J.; Barton, C.J.; Jenkins, D.G. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Andersson, L.L.; Butler, P.A.; Cox, D.M.; Herzberg, R.-D.; Mistry, A.; Parr, E. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 9ZE (United Kingdom); Grahn, T.; Greenlees, P.T. [Department of Physics, University of Jyväskylä, FI-40014 (Finland); Hauschild, K. [Department of Physics, University of Jyväskylä, FI-40014 (Finland); CSNSM-IN2P3-CNRS, Université Paris-Sud, 91406 Orsay (France); Herzan, A.; Jakobsson, U.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M. [Department of Physics, University of Jyväskylä, FI-40014 (Finland); and others

    2014-05-01

    A study of {sup 154}Sm through γ-ray and internal conversion electron coincidence measurements was performed using the Silicon And GErmanium spectrometer (SAGE). An upper limit for the ρ{sup 2}(E0;2{sub 2}{sup +}→2{sub 1}{sup +}) and measurement of the ρ{sup 2}(E0;4{sub 2}{sup +}→4{sub 1}{sup +}) monopole transitions strengths were determined. The extracted transition strength for each is significantly lower than that predicted by either the Bohr and Mottelson β-vibration description or the interacting boson model. Hence, the long standing interpretation of these states as a collective band built on the 0{sub 2}{sup +} state, which is conventionally assigned as a Bohr and Mottelson β vibration is questionable.

  4. A Very Compact and Low Profile UWB Planar Antenna with WLAN Band Rejection.

    Science.gov (United States)

    Syed, Avez; Aldhaheri, Rabah W

    2016-01-01

    A low-cost coplanar waveguide fed compact ultrawideband (UWB) antenna with band rejection characteristics for wireless local area network (WLAN) is proposed. The notch band characteristic is achieved by etching half wavelength C-shaped annular ring slot in the radiating patch. By properly choosing the radius and position of the slot, the notch band can be adjusted and controlled. With an overall size of 18.7 mm × 17.6 mm, the antenna turns out to be one of the smallest UWB antennas with band-notched characteristics. It has a wide fractional bandwidth of 130% (2.9-13.7 GHz) with VSWR < 2 and rejecting IEEE 802.11a and HIPERLAN/2 frequency band of 5.1-5.9 GHz. Stable omnidirectional radiation patterns in the H plane with an average gain of 4.4 dBi are obtained. The band-notch mechanism of the proposed antenna is examined by HFSS simulator. A good agreement is found between measured and simulated results indicating that the proposed antenna is well suited for integration into portable devices for UWB applications. PMID:27088125

  5. Numerical and experimental determination of in-structure temperature profiles

    Directory of Open Access Journals (Sweden)

    Zozulák Marek

    2015-06-01

    Full Text Available When building physics simulations are done initial conditions express the actual hygrothermal state of building envelope. For the temperature field simulations initial condition is represented by the initial temperature in the body profile at the start of heat transfer. In-structure temperature varies quickly so temperature initial conditions are often neglected. Nevertheless in specific cases initial conditions have to be taken into an account even when simple temperature field simulations are done. The contribution shows various temperature initial conditions determination for insulated construction of outdoor test cell. Comparison of measured and calculated temperature profiles in structure shows correctness of start-up pre-calculation initial condition consideration

  6. Experimental realisation of a double-core dispersion-compensating optical fibre for S-band optical communications

    International Nuclear Information System (INIS)

    Experimental realisation of a double-core optical fibre having a dispersion of -1750 ps km-1 nm-1 at a wavelength of 1470 nm is reported. This is the highest negative dispersion ever reported in the S-band (1450 nm to 1530 nm). The double-core optical fibre is characterised in terms of geometrical parameters, attenuation measurement, MFD measurement, bend loss measurement, etc. This work will be useful for the S-band optical fibre communication. (fibre optics)

  7. Experimental Investigation of the Neutral sheet Profile During Magnetic Reconnection

    International Nuclear Information System (INIS)

    During magnetic reconnection, a ''neutral sheet'' current is induced, heating the plasma. The resultant plasma thermal pressure forms a stationary equilibrium with the opposing magnetic fields. The reconnection layer profile holds significant clues about the physical mechanisms which control reconnection. On the Magnetic Reconnection Experiment [M. Yamada et al., Phys. Plasmas 4, 1936 (1997)], a quasi steady-state and axisymmetric neutral sheet profile has been measured precisely using a magnetic probe array with spatial resolution equal to one quarter of the ion gyro-radius. It was found that the reconnecting field profile fits well with a Harris-type profile [E. G. Harris, Il Nuovo Cimento 23, 115 (1962)], B(x) approximately tanh(x/delta). This agreement is remarkable since the Harris theory does not take into account reconnection and associated electric fields and dissipation. An explanation for this agreement is presented. The sheet thickness delta is found to be approximately 0.4 times the ion skin depth, which agrees with a generalized Harris theory incorporating non-isothermal electron and ion temperatures and finite electric field. The detailed study of additional local features of the reconnection region is also presented

  8. Double Bright Band Observations with High-Resolution Vertically Pointing Radar, Lidar, and Profiles

    Science.gov (United States)

    Emory, Amber E.; Demoz, Belay; Vermeesch, Kevin; Hicks, Michael

    2014-01-01

    On 11 May 2010, an elevated temperature inversion associated with an approaching warm front produced two melting layers simultaneously, which resulted in two distinct bright bands as viewed from the ER-2 Doppler radar system, a vertically pointing, coherent X band radar located in Greenbelt, MD. Due to the high temporal resolution of this radar system, an increase in altitude of the melting layer of approximately 1.2 km in the time span of 4 min was captured. The double bright band feature remained evident for approximately 17 min, until the lower atmosphere warmed enough to dissipate the lower melting layer. This case shows the relatively rapid evolution of freezing levels in response to an advancing warm front over a 2 h time period and the descent of an elevated warm air mass with time. Although observations of double bright bands are somewhat rare, the ability to identify this phenomenon is important for rainfall estimation from spaceborne sensors because algorithms employing the restriction of a radar bright band to a constant height, especially when sampling across frontal systems, will limit the ability to accurately estimate rainfall.

  9. Experimental study of the ℎ11/2 band in 113Sb

    Indian Academy of Sciences (India)

    S Ganguly; P Banerjee; A Dey; S Bhattacharya

    2011-08-01

    In the present work, the excited states of 113Sb were populated in the 100Mo(20Ne, 6) reaction at a beam energy of 136 MeV. States only up to 59/2− were observed in the = 2 band. Mean lifetimes for the five states (from 4460 to 7998 keV) were measured for the first time using Doppler shift attenuation method. An upper limit of the lifetime (0.14 ps) was estimated for the 9061 keV, 47/2− state. The (2) values, derived from the present lifetime results, correspond to a large quadrupole deformation of 2 = 0.32. The observed reduction in the experimental (2) values for the 918.4 keV (spin 39/2− → 35/2−) and 985 keV (spin 43/2− → 39/2−) transitions may be interpreted as due to the proton alignement in the 7/2 orbital. The dynamic moment of inertia was observed to be about half of the rigid body value at the highest observed frequency.

  10. Polarimetric remote sensing in oxygen A and B bands: sensitivity study and information content analysis for vertical profile of aerosols

    Science.gov (United States)

    Ding, Shouguo; Wang, Jun; Xu, Xiaoguang

    2016-05-01

    Theoretical analysis is conducted to reveal the information content of aerosol vertical profile in space-borne measurements of the backscattered radiance and degree of linear polarization (DOLP) in oxygen (O2) A and B bands. Assuming a quasi-Gaussian shape for aerosol vertical profile characterized by peak height H and half width γ (at half maximum), the Unified Linearized Vector Radiative Transfer Model (UNL-VRTM) is used to simulate the Stokes four-vector elements of upwelling radiation at the top of atmosphere (TOA) and their Jacobians with respect to H and γ. Calculations for different aerosol types and different combinations of H and γ values show that the wide range of gas absorption optical depth in O2 A and B band enables the sensitivity of backscattered DOLP and radiance at TOA to the aerosol layer at different altitudes. Quantitatively, DOLP in O2 A and B bands is found to be more sensitive to H and γ than radiance, especially over the bright surfaces (with large visible reflectance). In many O2 absorption wavelengths, the degree of freedom of signal (DFS) for retrieving H (or γ) generally increases with H (and γ) and can be close to unity in many cases, assuming that the composite uncertainty from surface and aerosol scattering properties as well as measurements is less than 5 %. Further analysis demonstrates that DFS needed for simultaneous retrieval of H and γ can be obtained from a combined use of DOLP measurements at ˜ 10-100 O2 A and B absorption wavelengths (or channels), depending on the specific values of H. The higher the aerosol layer, the fewer number of channels for DOLP measurements in O2 A and B bands are needed for characterizing H and γ. Future hyperspectral measurements of DOLP in O2 A and B bands are needed to continue studying their potential and their combination with radiance and DOLP in atmospheric window channels for retrieving the vertical profiles of aerosols, especially highly scattering aerosols, over land.

  11. Evaluating the use of electronegativity in band alignment models through the experimental slope parameter of lanthanum aluminate heterostructures

    International Nuclear Information System (INIS)

    In this work, photoelectron spectroscopy is used to characterize the band alignment of lanthanum aluminate heterostructures which possess a wide range of potential applications. It is found that our experimental slope parameter agrees with theory using the metal-induced gap states model while the interface induced gap states (IFIGS) model yields unsatisfactory results. We show that this discrepancy can be attributed to the correlation between the dielectric work function and the electronegativity in the IFIGS model. It is found that the original trend, as established largely by metals, may not be accurate for larger band gap materials. By using a new correlation, our experimental data shows good agreement of the slope parameter using the IFIGS model. This correlation, therefore, plays a crucial role in heterostructures involving wider bandgap materials for accurate band alignment prediction using the IFIGS model.

  12. Evaluating the use of electronegativity in band alignment models through the experimental slope parameter of lanthanum aluminate heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z. Q.; Chim, W. K. [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore); Chiam, S. Y; Pan, J. S. [Institute of Materials Research and Engineering, A-STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore); Ng, C. M. [GLOBALFOUNDRIES Singapore Pte. Ltd, 60 Woodlands Street 2, Singapore 738406 (Singapore)

    2011-11-01

    In this work, photoelectron spectroscopy is used to characterize the band alignment of lanthanum aluminate heterostructures which possess a wide range of potential applications. It is found that our experimental slope parameter agrees with theory using the metal-induced gap states model while the interface induced gap states (IFIGS) model yields unsatisfactory results. We show that this discrepancy can be attributed to the correlation between the dielectric work function and the electronegativity in the IFIGS model. It is found that the original trend, as established largely by metals, may not be accurate for larger band gap materials. By using a new correlation, our experimental data shows good agreement of the slope parameter using the IFIGS model. This correlation, therefore, plays a crucial role in heterostructures involving wider bandgap materials for accurate band alignment prediction using the IFIGS model.

  13. High-resolution polarimetric X-band weather radar observations at the Cabauw Experimental Site for Atmospheric Research

    NARCIS (Netherlands)

    Otto, T.; Russchenberg, H.W.J.

    2013-01-01

    In 2007, the horizontally scanning polarimetric X-band radar IDRA (IRCTR Drizzle Radar) was installed on top of the 213 m high mast at the Dutch meteorological observatory Cabauw Experimental Site for Atmospheric Research (CESAR) at Netherlands. This radar complements a large variety of measurement

  14. Measurement of fluid velocity using temperature profiles: Experimental verification

    Science.gov (United States)

    Cartwright, K.

    1979-01-01

    Temperature profiling has been used to predict the rate and direction of groundwater movement. A controlled field experiment was conducted to ascertain the validity of the rate calculations made using this method. The vertical velocity, or leakage, of groundwater between two aquifers was calculated utilizing both hydrologic and temperature measurements in a well drilled into the Paw Paw buried bedrock valley in northern Illinois. The experiment showed that accurate estimates of leakage can be made in stable boreholes where there are no geologic complications. Estimates utilizing temperature and hydrologic methods produced similar results for one of two aquicludes. However, the methods produced dissimilar results for the second aquiclude. It is speculated that the presence of a thin organic silt caused most of the problem; other complicating factors were lithologic variation and a very low hydraulic gradient. Nevertheless, the method appears to have great promise in many geologic environments. ?? 1979.

  15. Experimental study on G-band oversized backward wave oscillator driven by weakly relativistic electron beam

    International Nuclear Information System (INIS)

    We studied a G-band oversized backward wave oscillator (BWO) driven by a weakly relativistic electron beam of less than 100 kV. Rectangular corrugations are used as slow-wave structures having surface waves with upper cutoff frequencies above 150 GHz (G-band). We examine how dispersion characteristics of surface waves are affected by accuracy in machining the corrugation amplitude, width, and period length. Of these, accuracy in the amplitude has the largest effect. Uniformly distributed annular electron beams are generated by a disk-type cold cathode and injected into the G-band BWO. G-band BWO operations in 137 - 173 GHz and above 173 GHz are achieved by changing the corrugation amplitude. The radiation patterns are fairly broad, and the estimated radiation power is at kW level. (author)

  16. Intermediate band materials for more efficient solar energy use: quantum modelling and experimental realizations

    OpenAIRE

    Conesa, Jose Carlos; Wahnón Benarroch, Perla; Lucena, Raquel; Palacios Clemente, Pablo; Aguilera Bonet, Irene; Fresno, Fernando; Seminóvski Pérez, Yohanna

    2011-01-01

    The intermediate band (IB) solar cell (Fig. 1) has been proposed [1] to increase photovoltaic efficiency by a factor above 1.5, based on the absorption of two sub-bandgap photons to promote an electron across the bandgap. To realize this principle, that can be applied also to obtain efficient photocatalysis with sunlight, we proposed in recent years several materials where a metal or heavy element, substituting for an electropositive atom in a known semiconductor that has an appropriate band...

  17. Low profile, highly configurable, current sharing paralleled wide band gap power device power module

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, Brice; Killeen, Peter D.; Lostetter, Alex; Shaw, Robert; Passmore, Brandon; Hornberger, Jared; Berry, Tony M

    2016-08-23

    A power module with multiple equalized parallel power paths supporting multiple parallel bare die power devices constructed with low inductance equalized current paths for even current sharing and clean switching events. Wide low profile power contacts provide low inductance, short current paths, and large conductor cross section area provides for massive current carrying. An internal gate & source kelvin interconnection substrate is provided with individual ballast resistors and simple bolted construction. Gate drive connectors are provided on either left or right size of the module. The module is configurable as half bridge, full bridge, common source, and common drain topologies.

  18. Experimental determination of band offsets of NiO-based thin film heterojunctions

    International Nuclear Information System (INIS)

    The energy band diagrams of NiO-based solar cell structures that use various n-type oxide semiconductors such as ZnO, Mg0.3Zn0.7O, Zn0.5Sn0.5O, In2O3:Sn (ITO), SnO2, and TiO2 were evaluated by photoelectron yield spectroscopy. The valence band discontinuities were estimated to be 1.6 eV for ZnO/NiO and Mg0.3Zn0.7O/NiO, 1.7 eV for Zn0.5Sn0.5O/NiO and ITO/NiO, and 1.8 eV for SnO2/NiO and TiO2/NiO heterojunctions. By using the valence band discontinuity values and corresponding energy bandgaps of the layers, energy band diagrams were developed. Judging from the band diagram, an appropriate solar cell consisting of p-type NiO and n-type ZnO layers was deposited on ITO, and a slight but noticeable photovoltaic effect was obtained with an open circuit voltage (Voc) of 0.96 V, short circuit current density (Jsc) of 2.2 μA/cm2, and fill factor of 0.44.

  19. Radiation Efficient Unidirectional Low-Profile Slot Antenna Elements for X-Band Application

    Directory of Open Access Journals (Sweden)

    C. Löcker

    2005-01-01

    Full Text Available Slots in metallic ground planes are very promising candidates for conformal antenna applications. However, a low-profile unidirectional antenna requires a back reflector close to the slot and the resulting stripline feed causes strong excitation of parallel-plate modes. In this contribution, we consider unidirectional reflector-backed slot configurations with parallel-plate mode suppression by shorting pins. Starting from a parametric study with respect to shorting pin location and back reflector distance, we present a stripline-fed rectangular slot element with radiation efficiency of more than 80% and a bandwidth of about 5% at centre frequency 10GHz. A careful optimisation of shorting pin locations guarantees reliable parallel-plate mode suppression without deteriorating the slot radiation behaviour. Coupling coefficients between parallel and aligned rectangular slot elements are presented. For increased bandwidth applications, a bow-tie slot element with about 8% bandwidth and radiation efficiency of close to 80% is proposed.

  20. Experimental method for the evaluation of the susceptibility of materials to shear band formation

    OpenAIRE

    Tham R.

    2012-01-01

    In order to characterize materials with respect to their susceptibility to shear band formation at high strain rates, a modified Hopkinson pressure bar apparatus and hat-shaped steel specimens with a shear zone having a width significantly larger than the typical width of adiabatic bands are used. The sample is directly impacted by the striker. The force acting on the sample is measured with a PVDF-gauge between the sample and the output bar. The displacement is recorded with an electro-optic...

  1. Experimental reconstruction of the Berry curvature in a topological Bloch band

    Science.gov (United States)

    Weitenberg, Christof; Flaeschner, Nick; Rem, Benno; Tarnowski, Matthias; Vogel, Dominik; Luehmann, Dirk-Soeren; Sengstock, Klaus

    2016-05-01

    Topological properties lie at the heart of many fascinating phenomena in solid state systems such as quantum Hall systems or Chern insulators. The topology can be captured by the distribution of Berry curvature, which describes the geometry of the eigenstates across the Brillouin zone. Employing fermionic ultracold atoms in a hexagonal optical lattice, we engineer the Berry curvature of the Bloch bands using resonant driving and measure it with full momentum resolution. Our results pave the way to explore intriguing phases of matter with interactions in topological band structures.

  2. Experimental observation of G banding verifying X-ray workers' chromosome translocation detected by FISH

    International Nuclear Information System (INIS)

    Objective: FISH is the most effective way of detecting chromosome aberration and many factors affect its accuracy. G-banding is used to verify the results of early X-ray workers' chromosome translocation examined by FISH. Methods: The chromosome translocations of early X-ray workers have been analysed by FISH (fluorescence in situ hybridization) and G-banding, yields of translocation treated with statistics. Results: The chromosome aberrations frequencies by tow methods are closely related. Conclusion: FISH is a feasible way to analyse chromosome aberrations of X-ray workers and reconstruct dose

  3. Spatial profile of laser beam in antiresonant ring cavity: experimental study

    Science.gov (United States)

    Grabovski, Vitaly V.; Prokhorenko, Valentin I.; Yatskiv, Dmytro Y.

    1996-03-01

    This paper presents results of experimental studies of the spatial profile of the beam in lasers with an antiresonant ring. The near-field profile of the beam was measured by the pin-hole technique. In case of the active crystal placed into the ring, the beam profile was found to be Gaussian within a wide range of the pumping power. Variation of the width of the Gaussian profile is caused by the thermal lens in the active crystal. Measurements of the FWHM of the Gaussian profile demonstrated that it is proportional to the one-fourth power of the focal length of the thermal lens, as in the case of a stable cavity.

  4. An experimental study on spontaneous adiabatic shear band formation in electro-magnetically collapsing cylinders

    Science.gov (United States)

    Lovinger, Z.; Rittel, D.; Rosenberg, Z.

    2015-06-01

    The formation of shear bands in collapsing thick-walled cylinders (TWC) occurs in a spontaneous manner. The advantage of studying spontaneous, as opposed to forced, shear localization, is that it highlights the inherent susceptibility of the material to adiabatic shear banding without prescribed geometrical constraints. In the case of spontaneous shear localization, the role of microstructure (grain size and grain boundaries) on localization, is still unresolved. Using an electro-magnetic set-up, for the collapse of thick-walled cylinders, we examined the shear band formation and evolution in seven metallic alloys, with a wide range of strength and failure properties. To assess microstructural effects, we conducted systematic tests on copper and Ti6Al4V with different grain sizes. Our results match quite well with previously reported data on much larger specimens, showing the absence of a size effect, on adiabatic shearing. However, the measured shear band spacings, in this study, do not match the predictions of, existing analytical models, indicating that the physics of the problem needs to be better modeled.

  5. Experimental method for the evaluation of the susceptibility of materials to shear band formation

    Directory of Open Access Journals (Sweden)

    Tham R.

    2012-08-01

    Full Text Available In order to characterize materials with respect to their susceptibility to shear band formation at high strain rates, a modified Hopkinson pressure bar apparatus and hat-shaped steel specimens with a shear zone having a width significantly larger than the typical width of adiabatic bands are used. The sample is directly impacted by the striker. The force acting on the sample is measured with a PVDF-gauge between the sample and the output bar. The displacement is recorded with an electro-optical extensometer. The energy absorbed by the shearing process up to failure can be used as a reference for the susceptibility of materials to shear band formation. The method is demonstrated comparing the shear behavior of two high-strength steels with similar metallic structure and strength. Differences were found in the transition region between quasi-static and fully adiabatic shearing conditions where the energy up to rupture differs by 40 %. For fully adiabatic shear band formation, the deformation process of both materials equals. At extreme rates, shear processes are mainly governed by the thermodynamic properties of the materials. On the other hand, strength and structural properties play a role for low and intermediate rates where global and localized shear mechanisms occur in parallel.

  6. Experimental method for the evaluation of the susceptibility of materials to shear band formation

    Science.gov (United States)

    Tham, R.

    2012-08-01

    In order to characterize materials with respect to their susceptibility to shear band formation at high strain rates, a modified Hopkinson pressure bar apparatus and hat-shaped steel specimens with a shear zone having a width significantly larger than the typical width of adiabatic bands are used. The sample is directly impacted by the striker. The force acting on the sample is measured with a PVDF-gauge between the sample and the output bar. The displacement is recorded with an electro-optical extensometer. The energy absorbed by the shearing process up to failure can be used as a reference for the susceptibility of materials to shear band formation. The method is demonstrated comparing the shear behavior of two high-strength steels with similar metallic structure and strength. Differences were found in the transition region between quasi-static and fully adiabatic shearing conditions where the energy up to rupture differs by 40 %. For fully adiabatic shear band formation, the deformation process of both materials equals. At extreme rates, shear processes are mainly governed by the thermodynamic properties of the materials. On the other hand, strength and structural properties play a role for low and intermediate rates where global and localized shear mechanisms occur in parallel.

  7. Experimental Studies Of W-band Accelerator Structures At High Field

    CERN Document Server

    Hill, M E

    2001-01-01

    A high-gradient electron accelerator is desired for high- energy physics research, where frequency scalings of breakdown and trapping of itinerant beamline particles dictates operation of the accelerator at short wavelengths. The first results of design and test of a high-gradient mm-wave linac with an operating frequency at 91.392 GHz (W-band) are presented. A novel approach to particle acceleration is presented employing a planar, dielectric lined waveguide used for particle acceleration. The traveling wave fields in the planar dielectric accelerator (PDA) are analyzed for an idealized structure, along with a circuit equivalent model used for understanding the structure as a microwave circuit. Along with the W-band accelerator structures, other components designed and tested are high power rf windows, high power attenuators, and a high power squeeze-type phase shifter. The design of the accelerator and its components where eased with the aide of numerical simulations using a finite-difference electromagneti...

  8. Experimental investigation of 1 GW repeatable ultra-wide band pulse radiating source

    International Nuclear Information System (INIS)

    The single cycle pulse of 1.6 GW peak power with 20 Hz repetition-rate was generated. It radiated a peak power of more than 500 MW with a coaxial biconical antenna. The technological problems of the insulation and energy loss during generating and radiating high peak power ultra-wide band (UWB) pulse have been resolved. The experiments show that the material insulation and dispersion in sub-nanosecond pulse should be investigated deeply

  9. GFIT2: an experimental algorithm for vertical profile retrieval from near-IR spectra

    Science.gov (United States)

    Connor, Brian J.; Sherlock, Vanessa; Toon, Geoff; Wunch, Debra; Wennberg, Paul O.

    2016-08-01

    An algorithm for retrieval of vertical profiles from ground-based spectra in the near IR is described and tested. Known as GFIT2, the algorithm is primarily intended for CO2, and is used exclusively for CO2 in this paper. Retrieval of CO2 vertical profiles from ground-based spectra is theoretically possible, would be very beneficial for carbon cycle studies and the validation of satellite measurements, and has been the focus of much research in recent years. GFIT2 is tested by application both to synthetic spectra and to measurements at two Total Carbon Column Observing Network (TCCON) sites. We demonstrate that there are approximately 3° of freedom for the CO2 profile, and the algorithm performs as expected on synthetic spectra. We show that the accuracy of retrievals of CO2 from measurements in the 1.61μ (6220 cm-1) spectral band is limited by small uncertainties in calculation of the atmospheric spectrum. We investigate several techniques to minimize the effect of these uncertainties in calculation of the spectrum. These techniques are somewhat effective but to date have not been demonstrated to produce CO2 profile retrievals with sufficient precision for applications to carbon dynamics. We finish by discussing ongoing research which may allow CO2 profile retrievals with sufficient accuracy to significantly improve the scientific value of the measurements from that achieved with column retrievals.

  10. Experimental studies of a high power, X-band, coaxial gyroklystron

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J. [Naval Undersea Warfare Center, Newport, RI (United States); Xu, X.; Lawson, W.J.; Castle, M.; Hogan, B.P.; Granatstein, V.L.; Nusinovich, G.S.; Reiser, M. [Univ. of Maryland, College Park, MD (United States); Calame, J.P. [Naval Research Lab., Washington, DC (United States)

    1999-08-01

    Gyroklystrons are possible candidates for the RF sources in future linear colliders. A two-cavity and a three-cavity X-band gyroklystrons have been designed, built, and tested on the new 100 MW test bed at the University of Maryland. The theoretical design of the three-cavity X-band gyroklystron called for a peak power of 96 MW at an efficiency near 40% at a frequency of 8.568 GHz. In experiments, peak output power in the range of 75--85 MW at a frequency of 8.6 GHz has been measured with the three-cavity gyroklystron tube. The three-cavity tube was operated at electron beam voltage and current of 470 kV and 500 A, respectively. The efficiency is approximately 32% and the gain is approximately 30 dB. The pulse width of the output power signal is 1.7 {micro}s (full width at half maximum), while pulse repetition rate was limited to 2 Hz in this proof-of-principle study. This paper details the design, performance, and diagnostics of these two X-band gyroklystrons operating at the fundamental cyclotron resonance.

  11. Experimental studies of a high power, X-band, coaxial gyroklystron

    International Nuclear Information System (INIS)

    Gyroklystrons are possible candidates for the RF sources in future linear colliders. A two-cavity and a three-cavity X-band gyroklystrons have been designed, built, and tested on the new 100 MW test bed at the University of Maryland. The theoretical design of the three-cavity X-band gyroklystron called for a peak power of 96 MW at an efficiency near 40% at a frequency of 8.568 GHz. In experiments, peak output power in the range of 75--85 MW at a frequency of 8.6 GHz has been measured with the three-cavity gyroklystron tube. The three-cavity tube was operated at electron beam voltage and current of 470 kV and 500 A, respectively. The efficiency is approximately 32% and the gain is approximately 30 dB. The pulse width of the output power signal is 1.7 micros (full width at half maximum), while pulse repetition rate was limited to 2 Hz in this proof-of-principle study. This paper details the design, performance, and diagnostics of these two X-band gyroklystrons operating at the fundamental cyclotron resonance

  12. Experimental study on the deposition profile of the ICRF power and electron thermal diffusivity

    International Nuclear Information System (INIS)

    IN ICRF heating experiments the deposition profile in electrons has been derived experimentally, and comparison with theory has been performed. It is found that the deposition profile is relatively broad (Prf,e(r) = Prf,e(0)(1-(r/a)2)k with k = 1.8), and this is interpreted in terms of characteristics of the mode-converted Ion Bernstein Wave. The distribution of the rf power to each species (electrons, hydrogen and deuterium ions) is in good agreement with theoretical predictions. With the deposition profile experimentally obtained, the electron thermal diffusivity xe has been calculated, resulting in xe ∼0.65 m2/s at n-bare = 9 x 1019 m-3. (author)

  13. Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles

    International Nuclear Information System (INIS)

    Developments in gyrokinetic particle simulation enable the gyrokinetic toroidal code (GTC) to simulate turbulent transport in tokamaks with realistic equilibrium profiles and plasma geometry, which is a critical step in the code–experiment validation process. These new developments include numerical equilibrium representation using B-splines, a new Poisson solver based on finite difference using field-aligned mesh and magnetic flux coordinates, a new zonal flow solver for general geometry, and improvements on the conventional four-point gyroaverage with nonuniform background marker loading. The gyrokinetic Poisson equation is solved in the perpendicular plane instead of the poloidal plane. Exploiting these new features, GTC is able to simulate a typical DIII-D discharge with experimental magnetic geometry and profiles. The simulated turbulent heat diffusivity and its radial profile show good agreement with other gyrokinetic codes. The newly developed nonuniform loading method provides a modified radial transport profile to that of the conventional uniform loading method

  14. A theoretical and experimental investigation of an in-band pumped gain-switched thulium-doped fiber laser

    International Nuclear Information System (INIS)

    In this paper, the theoretical rate equation model of an in-band pumped gain-switched thulium-doped fiber (TDF) laser is investigated. The analytical formulations of pump energy threshold, peak power extraction efficiency, and pulse extraction efficiency are derived through analyzing the interaction process between the pump pulse and the laser pulse. They are useful for understanding, designing, and optimizing the in-band pumped TDF lasers in a 1.9 μm–2.1 μm wavelength region. The experiment with an all-fiber gain-switched TDF laser pumped by a 1.558-μm pulse amplifier is conducted, and our experimental results show good agreement with theoretical analysis

  15. Experimental Observation of Quantum Confinement in the Conduction Band of CdSe Quantum Dots

    International Nuclear Information System (INIS)

    X-ray absorption spectroscopy has been used to characterize the evolution in the conduction band (CB) density of states of CdSe quantum dots (QDs) as a function of particle size. We have unambiguously witnessed the CdSe QD CB minimum (CBM) shift to higher energy with decreasing particle size, consistent with quantum confinement effects, and have directly compared our results with recent theoretical calculations. At the smallest particle size, evidence for a pinning of the CBM is presented. Our observations can be explained by considering a size-dependent change in the angular-momentum-resolved states at the CBM

  16. Hematologic profile of hematophagous Desmodus rotundus bats before and after experimental infection with rabies virus

    Directory of Open Access Journals (Sweden)

    Marilene Fernandes de Almeida

    2014-06-01

    Full Text Available Introduction Hematophagous Desmodus rotundus bats play an important role in the rabies lifecycle. This study describes the hematological profile of these bats before and after experimental infection with rabies virus. Methods Cells counts were performed in a Neubauer chamber. Results The average values of erythrocytes and leucocytes counts in blood before experimental infections were 9.97 × 106mm3 and 4.80 × 103mm3, respectively. Neutrophils represented 69.9% of white blood cells and the lymphocytes represented 26.9%. Following the experimental infections, the average numbers of erythrocytes and leucocytes was 9.43 × 106mm3 and 3.98 × 103mm3, respectively. Neutrophils represented 40% of white blood cells and the lymphocytes represented 59%. Conclusions The hematological profile given in this study can serve as reference values for D. rotundus bats.

  17. Experimental Determination of Electromagnetic Propagation and Scattering Properties of Ice-Sheets at P-Band

    Science.gov (United States)

    Lin, Chung-Chi; Rommen, Björn; Buck, Christopher; Casal, Tania; Dall, Jørgen; Kusk, Anders; Nielsen, Ulrik; Corr, Hugh; Ginestet, Arnaud; Decerprit, Guillaume; Walker, Nick; Kristensen, Steen S.

    2014-05-01

    The electromagnetic (EM) propagation and scattering properties of the ice and its inclusions strongly affect radar reception signals in radio echo sounding of ice-sheets. In particular, those properties are very strongly dependent on the sensing frequency, with penetration depth rapidly decreasing with increasing frequency. Furthermore, the surface scattering signals, which mask the radar echoes from the depth, increases monotonically with frequency. In spite of those drawbacks, the recent interests in the use of P-band (435 MHz), as compared to the more established sensing frequencies at 60 and 150 MHz, are driven mainly by two reasons: (1) the use of a shorter wavelength improves the spatial selectivity of the sensor as a reasonably sized antenna system could generate narrow beams; (2) P-band is the lowest frequency band allocated for active sensing from space, potentially adequate for satellite-based sounding of ice-sheets. New datasets acquired by P-band radar sounders are becoming available, e.g. from the systems built by University of Kansas and ESA's POLARIS instrument built by Technical University of Denmark, thus opening a possibility to quantitatively compare the merits and drawback of ice sounding at P-band. This paper will report the result of the analysis carried out on the POLARIS data which were acquired over East Antarctica in Feb. 2011 in the frame of the Danish IceGrav 2011 campaign. More specifically, ice sounding measurements were performed over the areas of Dronning/Queen Maud Land and its coastal ice-shelves (e.g. Princess Astrid Coast and Fimbul ice-shelf), and Adelaide Island. Different ice types and regimes have been covered in order to build up a comprehensive catalogue of the ice electromagnetic properties. In addition to the POLARIS data, some in-situ data on the surface roughness, ice core data from EPICA and ice-shelf basal roughness data from an upward looking sonar experiment (Autosub Under Ice programme, 2005) have been gathered

  18. Numerical Simulation and Experimental Analysis of Photonic Band Gap in Hollow-Core Photonic Crystal Fibres

    Institute of Scientific and Technical Information of China (English)

    YUAN Jin-Hui; HOU Lan-Tian; ZHOU Gui-Yao; WEI Dong-Bin; CHEN Chao; WANG Qing-Yue; HU Ming-Lie; LIU Bo-Wen

    2008-01-01

    Based on the full-vector plane-wave method (FVPWM),a hollow-core photonic crystal fibre (HC-PCF) fabricated by using the improved stack-and-draw technique is simulated. Under given propagation constants β,several effective photonic band gaps with different sizes emerge within the visible wavelength range from 575 to 720hm.The fundamental mode and second-order mode lying in a part of PBGs are investigated.In the transmission spectrum tested,the positions of PBGs are discovered to be shifting to shorter wavelengths.The main reason is the existence of interstitial holes at nodes in the cladding region.In the later experiment,green light is observed propagating in the air-core region,and the result is more consistent with our theoretical simulation.

  19. X-band Dielectric Loaded Rf Driven Accelerator Structures Theoretical And Experimental Investigations

    CERN Document Server

    Zou, P

    2001-01-01

    An important area of application of high-power radio frequency (RF) and microwave sources is particle acceleration. A major challenge for the current worldwide research and development effort in linear accelerator is the search for a compact and affordable very-high-energy accelerator technology for the next generation supercolliders. It has been recognized for sometime that dielectric loaded accelerator structures are attractive candidates for the next generation very-high-energy linear accelerators, because they possess several distinct advantages over conventional metallic iris- loaded accelerator structures. However, some fundamental issues, such as RF breakdown in the dielectric, Joule heating, and vacuum properties of dielectric materials, are still the subjects of intense investigation, requiring the validation by experiments conducted at high power levels. An X-band traveling-wave accelerator based on dielectric-lined waveguide has been designed and constructed. Numerical calculation, bench measuremen...

  20. Experimental Studies of New Joint System for Thin-Walled Steel Profiles

    Directory of Open Access Journals (Sweden)

    Octavian Roşca

    2006-01-01

    Full Text Available The results and conclusions regarding the experimental test of the joint assembly of thin walled steel profile with and without strengthening elements (stiffeners are presented. The entire test series have been performed using the 5 mm thick KB600 thin-walled profiles and 3.5 mm thick KB450. In the paper will be presented the analysis of the joints connecting the KB600-5.5 steel profiles. The KONTIBEAM system is primarily made of two galvanized sheet profiles so denominated as KB, which are joined by means of steel sheets (usually of 10mm thickness, placed in between them. Connecting of this assembly (KB’s and connectors is realized by using M20 bolts put in φ22 holes, which work in friction with two contact planes. The tested joints are connected by means of 8.8 class HSFG bolts (High Strength Friction Grip. The main conclusions of the tests are that the contour bolted connections assure a good behavior between the KB profiles and the joint element. Due to their position the strengthening elements lead to an increase of the bearing capacity up to 30…35%with respect to the yield limit of the KB material. The use of such strengthening elements allows the optimum use of the KB profiles, thus leading to the reduction of the material consumption.

  1. Experimental high gradient testing of a 17.1 GHz photonic band-gap accelerator structure

    Science.gov (United States)

    Munroe, Brian J.; Zhang, JieXi; Xu, Haoran; Shapiro, Michael A.; Temkin, Richard J.

    2016-03-01

    We report the design, fabrication, and high gradient testing of a 17.1 GHz photonic band-gap (PBG) accelerator structure. Photonic band-gap (PBG) structures are promising candidates for electron accelerators capable of high-gradient operation because they have the inherent damping of high order modes required to avoid beam breakup instabilities. The 17.1 GHz PBG structure tested was a single cell structure composed of a triangular array of round copper rods of radius 1.45 mm spaced by 8.05 mm. The test assembly consisted of the test PBG cell located between conventional (pillbox) input and output cells, with input power of up to 4 MW from a klystron supplied via a TM01 mode launcher. Breakdown at high gradient was observed by diagnostics including reflected power, downstream and upstream current monitors and visible light emission. The testing procedure was first benchmarked with a conventional disc-loaded waveguide structure, which reached a gradient of 87 MV /m at a breakdown probability of 1.19 ×10-1 per pulse per meter. The PBG structure was tested with 100 ns pulses at gradient levels of less than 90 MV /m in order to limit the surface temperature rise to 120 K. The PBG structure reached up to 89 MV /m at a breakdown probability of 1.09 ×10-1 per pulse per meter. These test results show that a PBG structure can simultaneously operate at high gradients and low breakdown probability, while also providing wakefield damping.

  2. Experimental uncertainty estimation on the effective capture cross sections measured in the PROFIL experiments in Phenix

    International Nuclear Information System (INIS)

    A desire of increasing nuclear system safety and fuel depletion is directly translated by a better knowledge on nuclear data. PROFIL and PROFIL-2 experiments give integral information on capture and (n,2n) cross sections and cumulative fission yields for several isotopes (95Mo, 97Mo, 101Pd, 105Pd, 133Cs, 143Nd, 144Nd, 145Nd, 147Sm, 149Sm, 151Eu, 233U, 234U, 235U, 238Pu, 239Pu, 240Pu, 241Pu, 242Pu, 244Cm ...). Interpretation have been done many times in the past but without experimental uncertainty estimation. The cross section library JEFF-3.1.1, the covariance data base COMAC and the code system ERANOS-2.2 are used for this updated interpretation. This study is focusing on the uncertainty estimation on experimental values sensitive to capture cross sections. Three steps are required: the fluence scaling, the uncertainty propagation on the fluence and finally the uncertainty estimation on ratio variation of interest. This work is done with CONRAD using Bayesian adjustment and marginalization method. Mean C/E results and conclusions are identical to the previous interpretation. A fluence uncertainty of 1.4% is found for the two experimental pins of PROFIL-2 and 1.9% for PROFIL. Propagating this new information on the fluence to ratio variation of interest gives experimental uncertainties between 1% to 2.5% for the isotopes present in the experimental pins. One of the main results are for 238Pu, 239Pu, 240Pu, 241Pu and 242Pu capture cross sections: C/E are respectively equal to 1.03, 0.98, 0.97, 1.08 and 1.14 with an uncertainty lower than 2.5%. All the results will provide feedback on variance-covariance matrices for further works. (author)

  3. A flexible experimental setup for femtosecond time-resolved broad-band ellipsometry and magneto-optics

    International Nuclear Information System (INIS)

    A versatile experimental setup for femtosecond time-resolved ellipsometry and magneto-optical Kerr effect measurements in the visible light range is described. The apparatus is based on the pump-probe technique and combines a broad-band probing beam with an intense near-infrared pump. According to Fresnel scattering matrix formalism, the analysis of the reflected beam at different polarization states of the incident probe light allows one to determine the diagonal and the off-diagonal elements of the dielectric tensor in the investigated sample. Moreover, the pump-probe method permits to study the dynamics of the dielectric response after a short and intense optical excitation. The performance of the experimental apparatus is tested on CrO2 single crystals as a benchmark

  4. A flexible experimental setup for femtosecond time-resolved broad-band ellipsometry and magneto-optics

    Energy Technology Data Exchange (ETDEWEB)

    Boschini, F.; Hedayat, H.; Piovera, C.; Dallera, C. [Dipartimento di Fisica, Politecnico di Milano, p.zza Leonardo da Vinci 32, 20133 Milano (Italy); Gupta, A. [Department of Chemistry, University of Alabama, Tuscaloosa, Alabama 35487 (United States); Carpene, E., E-mail: ettore.carpene@polimi.it [CNR-IFN, Dipartimento di Fisica, Politecnico di Milano, p.zza Leonardo da Vinci 32, 20133 Milano (Italy)

    2015-01-15

    A versatile experimental setup for femtosecond time-resolved ellipsometry and magneto-optical Kerr effect measurements in the visible light range is described. The apparatus is based on the pump-probe technique and combines a broad-band probing beam with an intense near-infrared pump. According to Fresnel scattering matrix formalism, the analysis of the reflected beam at different polarization states of the incident probe light allows one to determine the diagonal and the off-diagonal elements of the dielectric tensor in the investigated sample. Moreover, the pump-probe method permits to study the dynamics of the dielectric response after a short and intense optical excitation. The performance of the experimental apparatus is tested on CrO{sub 2} single crystals as a benchmark.

  5. Self-presentation and emotional contagion on Facebook: new experimental measures of profiles' emotional coherence

    CERN Document Server

    Guazzini, Andrea; Cecchini, Cristina; Milani, Monica; Vilone, Daniele; Meringolo, Patrizia

    2016-01-01

    Social Networks allow users to self-present by sharing personal contents with others which may add comments. Recent studies highlighted how the emotions expressed in a post affect others' posts, eliciting a congruent emotion. So far, no studies have yet investigated the emotional coherence between wall posts and its comments. This research evaluated posts and comments mood of Facebook profiles, analyzing their linguistic features, and a measure to assess an excessive self-presentation was introduced. Two new experimental measures were built, describing the emotional loading (positive and negative) of posts and comments, and the mood correspondence between them was evaluated. The profiles "empathy", the mood coherence between post and comments, was used to investigate the relation between an excessive self-presentation and the emotional coherence of a profile. Participants publish a higher average number of posts with positive mood. To publish an emotional post corresponds to get more likes, comments and recei...

  6. Integrated modeling and experimental approach for determining transcription factor profiles from fluorescent reporter data

    Directory of Open Access Journals (Sweden)

    Jayaraman Arul

    2008-07-01

    Full Text Available Abstract Background The development of quantitative models of signal transduction, as well as parameter estimation to improve existing models, depends on the ability to obtain quantitative information about various proteins that are part of the signaling pathway. However, commonly-used measurement techniques such as Western blots and mobility shift assays provide only qualitative or semi-quantitative data which cannot be used for estimating parameters. Thus there is a clear need for techniques that enable quantitative determination of signal transduction intermediates. Results This paper presents an integrated modeling and experimental approach for quantitatively determining transcription factor profiles from green fluorescent protein (GFP reporter data. The technique consists of three steps: (1 creating data sets for green fluorescent reporter systems upon stimulation, (2 analyzing the fluorescence images to determine fluorescence intensity profiles using principal component analysis (PCA and K-means clustering, and (3 computing the transcription factor concentration from the fluorescence intensity profiles by inverting a model describing transcription, translation, and activation of green fluorescent proteins. We have used this technique to quantitatively characterize activation of the transcription factor NF-κB by the cytokine TNF-α. In addition, we have applied the quantitative NF-κB profiles obtained from our technique to develop a model for TNF-α signal transduction where the parameters were estimated from the obtained data. Conclusion The technique presented here for computing transcription factor profiles from fluorescence microscopy images of reporter cells generated quantitative data on the magnitude and dynamics of NF-κB activation by TNF-α. The obtained results are in good agreement with qualitative descriptions of NF-κB activation as well as semi-quantitative experimental data from the literature. The profiles computed from

  7. A computer program for processing experimental Compton profile of solids and liquids

    International Nuclear Information System (INIS)

    A computer program COMPRO has been developed for processing experimental Compton profile data of solids and liquids generated by inelastic gamma ray scattering using a solid state detector and a multichannel analyser. It also calculates the fourier transform of the profile yielding the one electron autocorrelation function in position space. The theory behind the method of calculation is outlined and the various data processing steps needed to be applied on the raw experimental data have been discussed in detail. A flow chart of the program is given and the various subroutines of the program, method of feeding the input data and the method of presenting the final result are briefly described. The procedure is illustrated by measurement on a polycrystalline sample of manganese. The actual listing of the program along with the test run input data and the test run output data is also given. (M.G.B.)

  8. Experimental estimations of viscoelastic properties of multilayer damped plates in broad-band frequency range

    CERN Document Server

    Ege, Kerem; Laulagnet, Bernard; Guyader, Jean-Louis

    2012-01-01

    Regarding lightweighting structures for aeronautics, automotive or construction applications, the level of performance of solutions proposed in terms of damping and isolation is fundamental. Hence multilayered plate appears as an interesting answer if damping performances are properly optimized. In this paper, a novel modal analysis method (Ege et al, JSV 325 (4-5), 2009) is used to identify viscoelastic properties (loss factors, Young's modulus) of "polyethylene thermoplastic / aluminum" bilayer plates. The thermoplastic is chosen for its high loss factors and relative low mass. The experimental method consists in a high-resolution technique (ESPRIT algorithm) which allows precise estimations of the viscoelastic properties even in frequency domains with high modal overlap (high damping or modal density). Experimental loss factors estimated from impact hammer excitations on the free-free plates highly corresponds with two theoretical estimations. In the first model (Guyader & Lesueur, JSV 58(1), 1978) the...

  9. Experimental measurements and numerical simulation of permittivity and permeability of Teflon in X band

    Directory of Open Access Journals (Sweden)

    Adriano Luiz de Paula

    2011-01-01

    Full Text Available Recognizing the importance of an adequate characterization of radar absorbing materials, and consequently their development, the present study aims to contribute for the establishment and validation of experimental determination and numerical simulation of electromagnetic materials complex permittivity and permeability, using a Teflon® sample. The present paper branches out into two related topics. The first one is concerned about the implementation of a computational modeling to predict the behavior of electromagnetic materials in confined environment by using electromagnetic three-dimensional simulation. The second topic re-examines the Nicolson-Ross-Weir mathematical model to retrieve the constitutive parameters (complex permittivity and permeability of a homogeneous sample (Teflon®, from scattering coefficient measurements. The experimental and simulated results show a good convergence that guarantees the application of the used methodologies for the characterization of different radar absorbing materials samples.

  10. Experimental design of the University of Maryland's high power, x-band gyroklystron

    International Nuclear Information System (INIS)

    In this paper the authors discuss a high peak-power, 1-2 μs, 10 GHz gyroklystron experiment that is nearing the operational stage at the University of Maryland. The device is expected to achieve power levels in excess of 30 MW via the interaction between a 500 kV, 160 A small-orbit beam and a TE010 gyroklystron circuit. Additional characteristics include an efficiency in excess of 40%, a gain in excess of 50 dB, and low phase noise. The authors present the detailed theoretical design of a four-cavity, stagger-tuned microwave circuit. A parametric characterization of the design is carried out with the aid of a partially self-consistent numerical code. Also presented are the results of a start oscillation calculation for the exact cold cavity field profiles of all relevant modes

  11. Experimental measurements and numerical simulation of permittivity and permeability of Teflon in X band

    OpenAIRE

    Adriano Luiz de Paula; Mirabel Cerqueira Rezende; Joaquim José Barroso

    2011-01-01

    Recognizing the importance of an adequate characterization of radar absorbing materials, and consequently their development, the present study aims to contribute for the establishment and validation of experimental determination and numerical simulation of electromagnetic materials complex permittivity and permeability, using a Teflon® sample. The present paper branches out into two related topics. The first one is concerned about the implementation of a computational modeling to predict the ...

  12. Experimental studies of an X-Band fundamental frequency coaxial gyroklystron

    Science.gov (United States)

    Cheng, Jack Chih-Kang

    Gyroklystron amplifiers have long been viewed as a strong candidate for the RF source in next generation linear colliders. A fundamental frequency X-Band gyroklystron has been designed, built and tested on the new 100 MW test bed at the University of Maryland. The design frequency is 8.568 GHz. This thesis details the design, construction, and performance of these first harmonic microwave circuits. Investigation was done on two circuits, a two-cavity and a three-cavity circuit. The achieved power levels for the final three-cavity tube was 70 MW at 30% efficiency according to calorimetric measurements. The original design calls for a peak power of 96 MW at an efficiency near 40%; however, the highest velocity ratio achieved was near 1.0 as opposed to the design number of 1.5. This device operated at electron beam voltages and currents of 469 kV and 506 A respectively. The final operating frequency was 8.601 GHz because of beam cavity detuning effects. The amplifier successfully operated in the linear regime with the output frequency closely following the input source frequency. A successful implementation of a high power coaxial microwave circuit was one of the main results from these fundamental frequency experiments because it paved the way for investigating high power coaxial circuits at the second harmonic.

  13. CCD photometry of globular cluster core structure. 2: U-band profiles for 15 candidate collapsed-core clusters

    Science.gov (United States)

    Lugger, Phyllis M.; Cohn, Haldan N.; Grindlay, Jonathan E.

    1995-01-01

    We present U-band CCD surface brightness profiles for 15 of the 21 globular clusters that have been identified as having collapsed cores by Djorgovski & King (1986). Fourteen of the clusters were observed with the Cerro Tololo 4 m telescope; NGC 7078 was observed with the Canada-France-Hawaii 3.6 m telescope (CFHT). We have fitted the profiles with seeing-convolved power laws, both with and without cores, to assess the evidence for central power-law structure and to place upper limits on core radius r(sub c). We find nine of the clusters (NGC 5946, NGC 6284, NGC 6293, NGC 6325, NGC 6342, NGC 6558, NGC 6624, NGC 6681, and NGC 7078) to have unresolved cores, with upper limits r(sub c) less than or = 1.9 arcsecs. Three of the clusters (NGC 6453, NGC 6522, and NGC 7099) have marginally resolved cores, with upper limits in the range 2.7 arcsecs less than or = r(sub c) less than or = 3.4 arcsecs. The remaining three clusters (NGC 6355, NGC 6397, and NGC 6752) have resolved cores. Of the latter three clusters, NGC 6355 and NGC 6752 are consistent with single-mass King model structure. The median cluster distances are 9.2 kpc for those with unresolved cores, 7.2 kpc for those with marginally resolved cores, and 4.1 kpc for those with resolved cores. The 13 clusters that do not resemble single-mass King models have central power-law structure with surface brightness slopes in the range of d ln S/d ln r = -0.6 to -0.8. These slopes are consistent with the models of Grabhorn et al. (1992) for clusters evolving beyond core collapse. The models include a centrally concentrated population of nonluminous remnants with masses in the range 1.2-1.4 solar mass, thus providing evidence for significant neutron star populations in most of our cluster sample. This finding is consistent with the observation of centrally concentrated low-mass X-ray binary and millisecond pulsar populations in several clusters.

  14. Experimental study of high-power Ka-band second-harmonic gyroklystron amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Sokolov, E.V.; Gachev, I.G.; Zasypkin, E.V.; Antakov, I.I. [Russian Academy of Science, Nizhny Novgorod (Russian Federation). Inst. of Applied Physics

    1995-11-01

    An experimental study was carried out to test high-harmonic gyroklystron amplifier concept. A two-cavity 35-GHz second-harmonic gyroklystron with the TE{sub 021} cavity mode has been built and tested in pulse operation. Output power of 258 kW with efficiency 18% and 17-dB gain have been produced at 72 kV beam voltage and 20-A beam current. Bandwidth of about 0.3 % have been observed. The restriction of the output power, efficiency and gain was caused by the spurious oscillations excited in the second cavity in the TE{sub 011} mode at the fundamental cyclotron frequency.

  15. Easy-to-Build Satellite Beacon Receiver for Propagation Experimentation at Millimeter Bands

    Directory of Open Access Journals (Sweden)

    F. Machado

    2014-04-01

    Full Text Available This paper describes the design and development of a digital satellite beacon receiver for propagation experimentation. Satellite beacons are frequently available for pointing large antennas, but such signals can be used for measuring rain attenuation and other phenomena as, for example, tropospheric scintillation. A fairly inexpensive beacon receiver has been built using off-the-shelf parts. This instrument is not at all bulky making it suitable for easy transportation. This article analyzes the receiver specifications, describes in detail its structure and presents some operational test results.

  16. Development of 100 GHz band high power gyrotron for fusion experimental reactor

    International Nuclear Information System (INIS)

    In JAERI, 1MW gyrotrons of 170GHz and 110GHz are under development for ITER (International Thermonuclear Experimental Reactor) and JT-60U, respectively. Both gyrotrons have a depressed collector for an efficiency improvement and a low loss synthetic diamond window that enables Gaussian beam output over 1MW. Three 110GHz gyrotrons are used on an electron cyclotron heating and current drive(ECH/ECCD) system on JT-60U, in which the output power of ∼0.8MW/3sec was generated from each gyrotron. As for 170GHz, output power of 1.2MW with electron beam of 85kV/49A was obtained on a short pulse gyrotron. The efficiency of ∼57% was attained at 1.1MW with the depressed collector. Based on these results, the 1MW 170GHz gyrotron for long pulse operation was fabricated. (author)

  17. AN EXPERIMENTAL INVESTIGATIONS INTO THE SPIKE PROFILE OBTAINED DURING ELECTROCHEMICAL HOLE DRILLING OF BLIND HOLES

    Directory of Open Access Journals (Sweden)

    P. V. Jadhav

    2011-02-01

    Full Text Available The Electrochemical Machining (ECM has in recent times emerged as an important advanced machining process. The improvement in machining accuracy of electrochemical machining (ECM continues to be a major challenge for user industries. This study focuses on the development of a precision ECM Process which uses with the traditional ECM. The feasibility of the proposed process has been experimentally verified.Attempts are being made to investigate optimum process parameters such as tool hole diameter, voltage, pressure etc. keeping feedrate, conductivity constant in the experimental proposed set up. The design of experiments was done by 2k factorial designs. The experimental results were analyzed by ANOVA (analysis of variance method and by plotting various graphs. In this paper we have analyzed how different parameters affect on the spike profile obtained during electrochemical drilling of blind hole.

  18. SIMULATION AND EXPERIMENTAL STUDY OF CHAOS GENERATION IN MICROWAVE BAND USING COLPITTS CIRCUIT

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Chaotic Colpitts circuits with fundamental frequency f* beyond 1GHz are studied by both circuit simulation and experiment using Philips' broadband transistor with threshold frequency of 25GHz. For the basic configuration of Colpitts circuit with f* of about 1.6GHz, broadband continuous power spectra could be obtained from both circuit simulations and experiments. The harmonics of the observed signal from Agilent PSA/ESA spectrum analyzer are as noticeable as far as 12GHz. A modified Colpitts circuit structure employing the parasitic inductance of BJT (Bipolar Junction Transistor) is also proposed and investigated. By circuit simulation, chaotic attractor and broadband continuous power spectra could be obtained from the modified Colpitts circuit with f* of about 3.5GHz. Because the parasitic effects of the prototype board, the experiment result of the modified Colpitts circuit does not agree well with the simulation result. The gap between the simulation and experimental result could be bridged by replacing the lumped circuit elements with distributed ones.

  19. Theoretical and experimental differential cross sections for electron impact excitation of the electronic bands of furfural

    Science.gov (United States)

    Jones, D. B.; Neves, R. F. C.; Lopes, M. C. A.; da Costa, R. F.; do N. Varella, M. T.; Bettega, M. H. F.; Lima, M. A. P.; García, G.; Limão-Vieira, P.; Brunger, M. J.

    2016-03-01

    We report results from a joint experimental and theoretical investigation into electron scattering from the important industrial species furfural (C5H4O2). Specifically, differential cross sections (DCSs) have been measured and calculated for the electron-impact excitation of the electronic states of C5H4O2. The measurements were carried out at energies in the range 20-40 eV, and for scattered-electron angles between 10° and 90°. The energy resolution of those experiments was typically ˜80 meV. Corresponding Schwinger multichannel method with pseudo-potential calculations, for energies between 6-50 eV and with and without Born-closure, were also performed for a sub-set of the excited electronic-states that were accessed in the measurements. Those calculations were undertaken at the static exchange plus polarisation-level using a minimum orbital basis for single configuration interaction (MOB-SCI) approach. Agreement between the measured and calculated DCSs was qualitatively quite good, although to obtain quantitative accord, the theory would need to incorporate even more channels into the MOB-SCI. The role of multichannel coupling on the computed electronic-state DCSs is also explored in some detail.

  20. Experimental demonstration of a novel bio-sensing platform via plasmonic band gap formation in gold nano-patch arrays

    CERN Document Server

    Grande, Marco; Stomeo, Tiziana; Morea, Giuseppe; Marani, Roberto; Marrocco, Valeria; Petruzzelli, Vincenzo; D'Orazio, Antonella; Cingolani, Roberto; De Vittorio, Massimo; de Ceglia, Domenico; Scalora, Michael

    2011-01-01

    We discuss the possibility of implementing a novel bio-sensing platform based on the observation of the shift of the leaky surface plasmon mode that occurs at the edge of the plasmonic band gap of metal gratings when an analyte is deposited on top of the metallic structure. We provide experimental proof of the sensing capabilities of a two-dimensional array of gold nano-patches by observing color variations in the diffracted field when the air overlayer is replaced with a small quantity of Isopropyl Alcohol (IPA). Effects of rounded corners and surface imperfections are also discussed. Finally, we also report proof of changes in color intensities as a function of the air/filling ratio of the structure and discuss their relation with the diffracted spectra.

  1. Experimental investigation and numerical simulations of void profile development in a vertical cylindrical pipe

    International Nuclear Information System (INIS)

    We present here an experimental investigation and some numerical simulations of void profile development in a vertical cylindrical pipe. This study is motivated by the lack of information dealing with the influence of entrance effects and bubble size evolution upon the multidimensional development of upward bubbly flow in pipe. The axial development of two-phase air-water upward bubbly and bubbly-to-slug transition flows in a vertical pipe is investigated experimentally first. Profiles of liquid mean velocity, liquid axial turbulent intensity, void fraction, bubble frequency, bubble velocity, mean equivalent bubble diameter and volumetric interfacial area are determined along the same test section at three axial locations. It is found that the bubbly-to-slug transition can be deduced from the simultaneous analysis of the different measured profiles. Local analysis of the studied bubbly flows shows that their development does not depend on the shape of the void distribution at the inlet. However, it is found that the bubble size evolution strongly affects the void distribution. Secondly, multidimensional numerical simulations of bubbly flows with very different gas injection modes are made with the help of the tridimensional two-fluid ASTRID code. It is shown that the classical models used to close the transverse momentum equations of the two-fluid model (lift and dispersion forces) do not capture the physical phenomena of bubble migration in pipe flows

  2. Experimental measurements of the detonation wave profile in a TATB based explosive

    Directory of Open Access Journals (Sweden)

    Decaris L.

    2011-01-01

    Full Text Available We report results of the experimental measurements of the detonation wave profile of the TATB based plastic bonded explosive T2 (97 w. % of TATB using VISAR and Heterodyne Velocimetry (HV – same as Photon Doppler Velocimetry. The experiment consists in initiating a detonation wave in a 15 mm diameter cylinder of explosive using an explosive wire detonator and an explosive booster. In order to obtain the particle velocity history in the reaction zone, we measure particle velocity at the interaction of the detonation front with an aluminized window or the free surface velocity of a metallic foil. Lithium Fluoride (LIF, PMMA and steel have been tested. Several shots have been performed for different lengths of explosive. We compare the VISAR and HV measurements. With LIF and steel, VISAR and HV diagnostics give very similar profiles. The ZND profile obtained on LIF is resolved with both techniques. With PMMA, HV gives a more accurate profile than VISAR in the reaction zone. There is no evidence of the influence of the explosive cylinder length.

  3. Experimental and theoretical study of dipole emission in the two-dimensional photonic band structure of the square lattice with dielectric cylinders

    International Nuclear Information System (INIS)

    Dipole radiation in a two-dimensional periodic dielectric structure is studied both theoretically and experimentally in this article. For the two-dimensional square lattice structure with dielectric cylinders, the emission power of an electric dipole in the photonic band structure is computed numerically by a combination of the plane wave method, the dyadic Green close-quote s function, the Poynting theorem, and the triangular integration method. The theoretical results are compared with experimental measurements in a microwave frequency region. The computed radiation spectra in the photonic band structure show good agreement with the experimentally measured results. copyright 1996 American Institute of Physics

  4. Aerosol extinction coefficient profile retrieval in the oxygen A-band considering multiple scattering atmosphere.Test case: SCIAMACHY nadir simulated measurements.

    OpenAIRE

    Corradini, S.; Università di Modena e Reggio Emilia; Cervino, M.; Istituto di Scienze dell’Atmosfera e del Clima, Consiglio Nazionale delle Ricerche, Bologna, Italy

    2006-01-01

    A multiple scattering inversion procedure for the aerosol extinction coefficient profile retrieval and error assessment in the oxygen A-band, for passive remote sensing instruments, has been developed. The procedure has been applied to SCIAMACHY nadir simulated measurements to investigate its effectiveness in the troposphere. The inversion procedure consists of a multiple scattering Forward Model, an inversion method and a complete sensitivity and error assessment tool. The Forward Mode...

  5. Experimental exploration of profile control in the Princeton Beta Experiment-Modified (PBX-M) tokamak

    International Nuclear Information System (INIS)

    The experimental program of the Princeton Beta Experiment-Modified (PBX-M) tokamak [Phys. Fluids B2, 1271 (1990)] is directed toward tailoring plasma profiles to achieve greater stability and confinement and to gain access to the second stability region. Modification of the current density profile has been achieved with lower-hybrid current drive (LHCD), leading to a regime free of global magnetohydrodynamic modes, while raising the value of q(0) above unity. The diffusion of the fast electrons produced by LHCD has been examined using two-dimensional hard x-ray imaging. Ion Bernstein waves (IBW) have been used for ion heating: a preliminary analysis shows that ion heating was spatially localized and in agreement with theoretical calculations. Divertor biasing has modified the electric field inside the last closed surface, resulting in the formation of a transport barrier, which in turn has reduced the threshold power of neutral beam injection (NBI) for H-mode transition by 25%

  6. Caracterisation Electromagnetique in-Situ De Sols En Bande L. Application a L'Identification De Profils Geologiques

    CERN Document Server

    Demontoux, François; Hernandez, Daniel Medina

    2009-01-01

    The development of instruments for remote sensing applications (active or passive) requires in situ validation measurements. The equipments (radar or radiometer) must be tested on real geological profiles. We must have accurate information on the profiles studied (permittivity, humidity, thickness of layers ...). Sensors (humidity), samples (thickness) or laboratory measurements (permittivity) provide local data about the profile while the remote sensing equipment is performing global measurements on a geological structure. The present work describes an in situ characterization bench test, based on two horn antennas, associated with an identification profiles software we developed to obtain comprehensive and instantaneous information on the geological profiles.

  7. Experimental evaluation of fatty acid profiles as a technique to determine dietary composition in benthic elasmobranchs.

    Science.gov (United States)

    Beckmann, Crystal L; Mitchell, James G; Seuront, Laurent; Stone, David A J; Huveneers, Charlie

    2013-01-01

    Fatty acid (FA) analysis is a tool for dietary investigation that complements traditional stomach content analyses. Controlled feeding experiments were used to determine the extent to which the FA composition of diet is reflected in the liver and muscle tissue of the Port Jackson shark Heterodontus portusjacksoni. Over 10 wk, two groups of sharks were fed prawns or squid, which have distinct FA profiles. The percentage of total FA was significantly different for shark liver and muscle tissue when comparing controls with prawn- and squid-fed sharks. Compared with experimentally fed sharks, control shark muscle and liver had higher levels of 18:1n-9 and 20:2n-9. When comparing prawn- and squid-fed sharks, only liver tissue showed a significant difference in FA profiles. The livers of prawn-fed sharks were comparatively higher in 18:1n-7, 22:5n-3, 20:0, and 18:1n-9, while the squid-fed sharks had higher levels of 16:0 and 22:6n-3. These FAs in shark liver tissue were all reflective of higher amounts in their respective dietary items, demonstrating the conservative transfer of FA from diet to liver tissue. This study shows that liver and muscle FA profiles can be used as indicators of dietary change through the comparison of controls and fed sharks. The timescale of this study may not have been sufficient for capturing the integration of FA into muscle tissue because only liver FA profiles were useful to distinguish between sharks fed different diets. These findings have important implications for sampling design where FA profiles are used to infer dietary preferences. PMID:23434786

  8. Modeling and Experimental Tests of a Mechatronic Device to Measure Road Profiles Considering Impact Dynamics

    DEFF Research Database (Denmark)

    Souza, A.; Santos, Ilmar

    2002-01-01

    the mechanism components. By modeling impacts between a wheel and the road by Newton´s Law, the complete dynamics of the system can be predicted, and the operational range (velocity limits) of the mechanism can be defined based on the mathematical model. Key words: multibody dynamics, impact dynamics...... dynamics is led with help of a set of non-linear equations of motion obtained using Newton-Euler-Jourdain´s Method. Such a set of equation is numerically solved and the theoretical results are compared with experimental carried out with a laboratory prototype. Comparisons show that the theoretical model...... predicts well the mechanism movements. However it was also experimentally observed that the contact between the wheels and the road profile is not permanent. To analyze the non-contact between the wheels and the road, the Newton-Euler´s Method is used to calculate forces and moments of reactions between...

  9. Nitrogen diffusion and nitrogen depth profiles in expanded austenite: experimental assessment, numerical simulation and role of stress

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Dahl, Kristian Vinter; Somers, Marcel A. J.

    2008-01-01

    The present paper addresses the experimental assessment of the concentration dependent nitrogen diffusion coefficient in stress free expanded austenite foils from thermogravimetry, the numerical simulation of nitrogen concentration depth profiles on growth of expanded austenite into stainless ste...

  10. Design and Implementation of Low Profile Antenna for Dual-Band Applications Using Rotated E-Shaped Conductor-Backed Plane

    Directory of Open Access Journals (Sweden)

    Mahdi Jalali

    2014-01-01

    Full Text Available A novel configuration of a printed monopole antenna with a very compact size for satisfying WLAN operations at the 5.2/5.8 GHz and also for X-band operations at the 10 GHz has been proposed. The antenna includes a simple square-shaped patch as the radiator, the rotated U-shaped conductor back plane element with embedded strip on it, and the partial rectangular ground surface. By using the rotated U-shaped conductor-backed plane with proper values, good impedance matching and improvement in bandwidth can be achieved, at the lower and upper bands. The impedance bandwidth for S11<-10 dB is about 1.15 GHz for 5 GHz band and 5.3 GHz for X-band. The measured peak gains are about 1.9 dBi at WLAN-band and 4.2 dBi at X-band. The experimental results represent that the realized antenna with good omnidirectional radiation characteristics, enough impedance bandwidth, and reasonable gains can be appropriate for various applications of the future developed technologies and handheld devices.

  11. Experimental studies of x-ray laser spectral profiles: Observation of gain narrowing and saturation behavior

    International Nuclear Information System (INIS)

    We discuss our recent measurements of the spectral width of the 206.38 Angstrom x-ray laser transition in Ne-like Se. These measurements used a high-resolution grating spectrometer and were performed over a wide range of laser amplifier lengths. The data have enabled us to extrapolate the intrinsic line width and to observe the effects of gain-narrowing and saturation on the line profile. We find an intrinsic width which is 1.4 times the Doppler width, we observe gain-narrowing in intermediate length amplifiers, and we observe no re-broadening in long, saturated amplifiers. These results suggest that collisional line-broadening has a significant effect on the line profile and saturation behavior of this laser. We discuss modeling we have performed in order to simulate the experimental data, and we discuss future experimental and theoretical efforts we believe are necessary in order to understand line broadening and line transfer issues in x-ray laser plasmas

  12. Experimental investigation of a nanofluid absorber employed in a low-profile, concentrated solar thermal collector

    Science.gov (United States)

    Li, Qiyuan; Zheng, Cheng; Mesgari, Sara; Hewakuruppu, Yasitha L.; Hjerrild, Natasha; Crisostomo, Felipe; Morrison, Karl; Woffenden, Albert; Rosengarten, Gary; Scott, Jason A.; Taylor, Robert A.

    2015-12-01

    Recent studies [1-3] have demonstrated that nanotechnology, in the form of nanoparticles suspended in water and organic liquids, can be employed to enhance solar collection via direct volumetric absorbers. However, current nanofluid solar collector experimental studies are either relevant to low-temperature flat plate solar collectors (100 °C) indoor laboratory-scale concentrating solar collectors [1, 5]. Moreover, many of these studies involve in thermal properties of nanofluid (such as thermal conductivity) enhancement in solar collectors by using conventional selective coated steel/copper tube receivers [6], and no full-scale concentrating collector has been tested at outdoor condition by employing nanofluid absorber [2, 6]. Thus, there is a need of experimental researches to evaluate the exact performance of full-scale concentrating solar collector by employing nanofluids absorber at outdoor condition. As reported previously [7-9], a low profile (solar thermal concentrating collector was designed and analysed which can potentially supply thermal energy in the 100-250 °C range (an application currently met by gas and electricity). The present study focuses on the design and experimental investigation of a nanofluid absorber employed in this newly designed collector. The nanofluid absorber consists of glass tubes used to contain chemically functionalized multi-walled carbon nanotubes (MWCNTs) dispersed in DI water. MWCNTs (average diameter of 6-13 nm and average length of 2.5-20 μm) were functionalized by potassium persulfate as an oxidant. The nanofluids were prepared with a MCWNT concentration of 50 +/- 0.1 mg/L to form a balance between solar absorption depth and viscosity (e.g. pumping power). Moreover, experimentally comparison of the thermal efficiency between two receivers (a black chrome-coated copper tube versus a MWCNT nanofluid contained within a glass tubetube) is investigated. Thermal experimentation reveals that while the collector efficiency

  13. Experimental study on temperature profile of fixed - bed gasification of oil-palm fronds

    Science.gov (United States)

    Atnaw, Samson M.; Sulaiman, Shaharin A.; Moni, M. Nazmi Z.

    2012-06-01

    Currently the world's second largest palm oil producer Malaysia produces large amount of oil palm biomass each year. The abundance of the biomass introduces a challenge to utilize them as main feedstock for heat and energy generation. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. OPF feedstock of one cubic inch in individual size with 15% average moisture content was utilized. An average pyrolysis zone temperature of 324°Cand an average oxidation zone temperature of 796°Cwere obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952°Cwas obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. The recorded temperature profiles produced closely similar patterns with the temperature profiles recorded from the gasification of woody materials. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF

  14. Research on intermediate band solar cells and development of experimental techniques for their characterization under concentrated illumination

    OpenAIRE

    García-Linares Fontes, Pablo

    2012-01-01

    Abstract This work is a contribution to the research and development of the intermediate band solar cell (IBSC), a high efficiency photovoltaic concept that features the advantages of both low and high bandgap solar cells. The resemblance with a low bandgap solar cell comes from the fact that the IBSC hosts an electronic energy band -the intermediate band (IB)- within the semiconductor bandgap. This IB allows the collection of sub-bandgap energy photons by means of two-step photon absorption ...

  15. Automated comparison of Bayesian reconstructions of experimental profiles with physical models

    International Nuclear Information System (INIS)

    In this work we developed an expert system that carries out in an integrated and fully automated way i) a reconstruction of plasma profiles from the measurements, using Bayesian analysis ii) a prediction of the reconstructed quantities, according to some models and iii) an intelligent comparison of the first two steps. This system includes systematic checking of the internal consistency of the reconstructed quantities, enables automated model validation and, if a well-validated model is used, can be applied to help detecting interesting new physics in an experiment. The work shows three applications of this quite general system. The expert system can successfully detect failures in the automated plasma reconstruction and provide (on successful reconstruction cases) statistics of agreement of the models with the experimental data, i.e. information on the model validity. (author)

  16. DNB location with axially disuniform heat flux profiles and flow obstructions: an experimental contribution

    International Nuclear Information System (INIS)

    Safety requirements for LWR's become more and more severe. So, further information is needed about the influence on the DNB level of axial heat flux disuniformities and local obstructions which accidentally may block, partially or totally, the flow area, following different incidental mechanisms (deposition, ballooning, rod bowing, etc.). As it is well known many mixing codes have been developed up to now, based on different hypothesis which physically cannot be valid any more if abrupt changes are formed along the flow area. Two phase flow DNB mechanisms also may be greatly influenced by different types of heat flux profiles and flow obstructions. So the whole channel through which the two phase mixture flows may exhibit a different behaviour for what pertains to the thermal crisis, both for the value of the critical power and the location of the DNB point. For this, an experimental investigation has been performed, employing freon 12 as water-scalar-fluid and a four rod bundle test section

  17. Experimental study of the variation of spectrum line profiles with time (1962)

    International Nuclear Information System (INIS)

    This study relates to a device conceived by C. BRETON, M. CAPET and F. WAELBROECK and submitted at the Fifth International Conference on Ionization Phenomena in Gases (Munich 1961). To calibrate the device and to know its accurate possibilities, noise in photomultipliers had to be investigated. For weak light signals this investigation has shown that the Schottky effect explains this noise and that there is a strict relation between the time resolution and the accuracy of the results. These results are applied to measurements of Stark Effect broadening of the Dβ line emitted by the plasma of an electrode-less-gun. The densities calculated from the experimental profiles are in good agreement with the densities calculated from magnetic measurements. (authors)

  18. Experimental demonstration of tomographic slit technique for measurement of arbitrary intensity profiles of light beams

    Science.gov (United States)

    Soto, José; Rendón, Manuel; Martín, Manuel

    1997-10-01

    We demonstrate experimentally an optical imaging method that makes use of a slit to collect tomographic projection data of arbitrarily shaped light beams; a tomographic backprojection algorithm is then used to reconstruct the intensity profiles of these beams. Two different implementations of the method are presented. In one, a single slit is scanned and rotated in front of the laser beam. In the other, the sides of a polygonal slit, which is linearly displaced in a x-y plane perpendicular to the beam, are used to collect the data. This latter version is more suitable than the other for adaptation at micrometer-size scale. A mathematical justification is given here for the superior performance against laser-power fluctuations of the tomographic slit technique compared with the better-known tomographic knife-edge technique.

  19. Metabolomic profiling of faecal extracts from Cryptosporidium parvum infection in experimental mouse models.

    Directory of Open Access Journals (Sweden)

    Josephine S Y Ng Hublin

    Full Text Available Cryptosporidiosis is a gastrointestinal disease in humans and animals caused by infection with the protozoan parasite Cryptosporidium. In healthy individuals, the disease manifests mainly as acute self-limiting diarrhoea, but may be chronic and life threatening for those with compromised immune systems. Control and treatment of the disease is challenged by the lack of sensitive diagnostic tools and broad-spectrum chemotherapy. Metabolomics, or metabolite profiling, is an emerging field of study, which enables characterisation of the end products of regulatory processes in a biological system. Analysis of changes in metabolite patterns reflects changes in biochemical regulation, production and control, and may contribute to understanding the effects of Cryptosporidium infection in the host environment. In the present study, metabolomic analysis of faecal samples from experimentally infected mice was carried out to assess metabolite profiles pertaining to the infection. Gas-chromatography mass spectrometry (GC-MS carried out on faecal samples from a group of C. parvum infected mice and a group of uninfected control mice detected a mean total of 220 compounds. Multivariate analyses showed distinct differences between the profiles of C. parvum infected mice and uninfected control mice,identifying a total of 40 compounds, or metabolites that contributed most to the variance between the two groups. These metabolites consisted of amino acids (n = 17, carbohydrates (n = 8, lipids (n = 7, organic acids (n = 3 and other various metabolites (n = 5, which showed significant differences in levels of metabolite abundance between the infected and uninfected mice groups (p < 0.05. The metabolites detected in this study as well as the differences in abundance between the C. parvum infected and the uninfected control mice, highlights the effects of the infection on intestinal permeability and the fate of the metabolites as a result of nutrient scavenging by the

  20. Expression Profiling after Prolonged Experimental Febrile Seizures in Mice Suggests Structural Remodeling in the Hippocampus.

    Directory of Open Access Journals (Sweden)

    Bart C Jongbloets

    Full Text Available Febrile seizures are the most prevalent type of seizures among children up to 5 years of age (2-4% of Western-European children. Complex febrile seizures are associated with an increased risk to develop temporal lobe epilepsy. To investigate short- and long-term effects of experimental febrile seizures (eFS, we induced eFS in highly febrile convulsion-susceptible C57BL/6J mice at post-natal day 10 by exposure to hyperthermia (HT and compared them to normotherm-exposed (NT mice. We detected structural re-organization in the hippocampus 14 days after eFS. To identify molecular candidates, which entrain this structural re-organization, we investigated temporal changes in mRNA expression profiles eFS 1 hour to 56 days after eFS. We identified 931 regulated genes and profiled several candidates using in situ hybridization and histology at 3 and 14 days after eFS. This is the first study to report genome-wide transcriptome analysis after eFS in mice. We identify temporal regulation of multiple processes, such as stress-, immune- and inflammatory responses, glia activation, glutamate-glutamine cycle and myelination. Identification of the short- and long-term changes after eFS is important to elucidate the mechanisms contributing to epileptogenesis.

  1. Design and Experimental Approach to the Construction of a Human Signal-Molecule-Profiling Database

    Directory of Open Access Journals (Sweden)

    Xinyan Zhao

    2013-12-01

    Full Text Available The human signal-molecule-profiling database (HSMPD is designed as a prospective medical database for translational bioinformatics (TBI. To explore the feasibility of low-cost database construction, we studied the roadmap of HSMPD. A HSMPD-oriented tool, called “signal-molecule-profiling (SMP chip” was developed for data acquisition, which can be employed in the routine blood tests in hospitals; the results will be stored in the HSMPD system automatically. HSMPD system can provide data services for the TBI community, which generates a stable income to support the data acquisition. The small-scale experimental test was performed in the hospital to verify SMP chips and the demo HSMPD software. One hundred and eighty nine complete SMP records were collected, and the demo HSMPD system was also evaluated in the survey study on patients and doctors. The function of SMP chip was verified, whereas the demo HSMPD software needed to be improved. The survey study showed that patients would only accept free tests of SMP chips when they originally needed blood examinations. The study indicated that the construction of HSMPD relies on the self-motivated cooperation of the TBI community and the traditional healthcare system. The proposed roadmap potentially provides an executable solution to build the HSMPD without high costs.

  2. Comparison of the various methods for the direct calculation of the transmission functions of the 15-micron CO2 band with experimental data

    Science.gov (United States)

    1978-01-01

    Various methods for calculating the transmission functions of the 15 micron CO2 band are described. The results of these methods are compared with laboratory measurements. It is found that program P4 provides the best agreement with experimental results on the average.

  3. Summary of Turbulence Data Obtained During United Air Lines Flight Evaluation of an Experimental C Band (5.5 cm) Airborne Weather Radar

    Science.gov (United States)

    Coe, E. C.; Fetner, M. W.

    1954-01-01

    Data on atmospheric turbulence in the vicinity of thunderstorms obtained during a flight evaluation of an experimental C band (5.5 cm) airborne radar are summarized. The turbulence data were obtained with an NACA VGH recorder installed in a United Air Lines DC-3 airplane.

  4. Experimental determination of noble gas, SF6 and CO2 flow profiles through a porous sandstone

    Science.gov (United States)

    Kilgallon, Rachel; Gilfillan, Stuart; Edlmann, Katriona; McDermott, Chris

    2016-04-01

    The noble gases (He, Ne, Ar, Kr and Xe) and SF6 have recently been used as artificial and inherent tracers of CO2 flow and migration from within[1,2] and from geological reservoirs[3]. However, outstanding questions remain, particularly regarding the flow behaviour of the noble gases compared to CO2. Here we present results from specially constructed experimental equipment, which has been used to determine the factors affecting transport of noble gases relative to CO2 in a porous sandstone. The experimental setup consists of a sample loop that can be loaded with a desired gas mixture. This sample can be released as a pulse into a feeder gas stream through a flow cell. The flow cell consists of a 3.6 cm diameter core, which can be of any length. The sample is surrounded by aluminium foil and treated with epoxy resin inside stainless steel tubing. The flow cell is encased by two purpose designed dispersion end plates. Real-time analysis of the arrival peaks of the gases downstream is recorded using a Quadrupole Mass Spectrometer (QMS). For the experiments, a 0.96 m core of Fell Sandstone was selected to represent a porous media. Noble gases and SF6 pulses were flowed through a CO2 carrier gas at five different pressure gradients (10 - 50 kPa) with arrival profiles measured using the QMS. Surprisingly, peak arrival times of He were slower than the other noble gases at each pressure gradient. The differences in peak arrival times between He and other noble gases increased as pressure decreased and the curve profiles for each noble gas differ significantly. The heavier noble gases (Kr and Xe) along with SF6 show a steeper peak rise at initial appearance, but have a longer duration profile than the He curves. Interestingly, the breakthrough curve profiles for both Kr and Xe were similar to SF6 indicating that Kr and Xe could be substituted for SF6, which is a potent greenhouse gas, in tracing applications. In addition, CO2 pulses were passed through a N2 carrier gas. The

  5. Calculus of bands and profiles of study the system mirror - resonance of the Fibonacci Pt/Zn

    Science.gov (United States)

    Castro-Arce, Lamberto; Figueroa-Navarro, Carlos; Campos-Garcia, Julio; Molinar-Tabares, Martin; Ramos-Mendieta, Felipe; Manzanares-Martinez, Betzabe

    2015-03-01

    In order to analyze the behavior of a mirror - located resonance of 2pi, in a given system and with a given filling factor equal to 0.4 a study has been realized in an arrangement fibonacci, also in periodic slabs jobs. It is observed how in a study of profile that some waves are annulled giving birth to the mirror placed in 2pi. With regard to the resonance in a profile study the maxima are in certain structure Pt Pt Zn Pt Pt. Even if we increase the number of repetitions these are preserved, that means that they are related to effects of segments isolated inside the multilayer.

  6. Experimental alteration of molybdenite: evaluation of the Re-Os system, infrared spectroscopic profile and polytype

    Science.gov (United States)

    Suzuki, Katsuhiko; Kagi, Hiroyuki; Nara, Masayuki; Takano, Bokuichiro; Nozaki, Yoshiyuki

    2000-01-01

    removal of the impurity band in molybdenite. It was also found in this study, however, that change in IR profile does not correlate with the Re-Os fractionation and, therefore, IR measurement solely is not useful to detect disturbance of Re-Os systematics of molybdenite in alteration.

  7. High-resolution H-band spectroscopy of Be stars with SDSS-III/apogee. I. New Be stars, line identifications, and line profiles

    Energy Technology Data Exchange (ETDEWEB)

    Chojnowski, S. Drew; Majewski, Steven R.; Hall, Matthew; Beaton, Rachael; Burton, Adam; Damke, Guillermo; Wilson, John [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Whelan, David G. [Department of Physics, Austin College, 900 N. Grand Ave., Sherman, TX 75090 (United States); Wisniewski, John P. [Department of Physics and Astronomy, The University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Shetrone, Matthew [Department of Astronomy, The University of Texas at Austin, 2515 Speedway, Stop C1400 Austin, Texas 78712-1205 (United States); Eikenberry, Steve [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Hasselquist, Sten; Holtzman, Jon A.; Brewington, Howard; Brinkmann, J. [Apache Point Observatory and New Mexico State University, P.O. Box 59, Sunspot, NM, 88349-0059 (United States); Mészáros, Szabolcs [ELTE Gothard Astrophysical Observatory, 1H-9704 Szombathely, Szent Imre herceg st. 112 (Hungary); Nidever, David [Department of Astronomy, University of Michigan, 830 Dennison, 500 Church St., Ann Arbor, MI 48109-1042 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Zasowski, Gail [Department of Physics and Astronomy, Johns Hopkins University, Bloomberg Center for Physics and Astronomy, Room 366, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Bizyaev, Dmitry, E-mail: drewski@virginia.edu [Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802 (United States); and others

    2015-01-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has amassed the largest ever collection of multi-epoch, high-resolution (R∼22,500), H-band spectra for B-type emission line (Be) stars. These stars were targeted by APOGEE as telluric standard stars and subsequently identified via visual inspection as Be stars based on H i Brackett series emission or shell absorption in addition to otherwise smooth continua and occasionally non-hydrogen emission features. The 128/238 APOGEE Be stars for which emission had never previously been reported serve to increase the total number of known Be stars by ∼6%. Because the H band is relatively unexplored compared to other wavelength regimes, we focus here on identification of the H-band lines and analysis of the emission peak velocity separations (Δv{sub p}) and emission peak intensity ratios (V/R) of the usually double-peaked H i and non-hydrogen emission lines. H i Br11 emission is found to preferentially form in the circumstellar disks at an average distance of ∼2.2 stellar radii. Increasing Δv{sub p} toward the weaker Br12–Br20 lines suggests these lines are formed interior to Br11. By contrast, the observed IR Fe ii emission lines present evidence of having significantly larger formation radii; distinctive phase lags between IR Fe ii and H i Brackett emission lines further supports that these species arise from different radii in Be disks. Several emission lines have been identified for the first time including C i 16895, a prominent feature in the spectra for almost a fifth of the sample and, as inferred from relatively large Δv{sub p} compared to the Br11–Br20, a tracer of the inner regions of Be disks. Emission lines at 15760 Å and 16781 Å remain unidentified, but usually appear along with and always have similar line profile morphology to Fe ii 16878. Unlike the typical metallic lines observed for Be stars in the optical, the H-band metallic lines, such as Fe ii 16878, never exhibit any

  8. An approximation of the Voigt I profile for the fitting of experimental X-ray absorption data

    Energy Technology Data Exchange (ETDEWEB)

    Teodorescu, C.M. (Laboratoire de Spectroscopie Atomique et Ionique and LURE, Bat. 350, Universite Paris Sud, 91405 Orsay (France)); Esteva, J.M. (Laboratoire de Spectroscopie Atomique et Ionique and LURE, Bat. 350, Universite Paris Sud, 91405 Orsay (France)); Karnatak, R.C. (Laboratoire de Spectroscopie Atomique et Ionique and LURE, Bat. 350, Universite Paris Sud, 91405 Orsay (France)); El Afif, A. (Laboratoire de Spectroscopie Atomique et Ionique and LURE, Bat. 350, Universite Paris Sud, 91405 Orsay (France))

    1994-06-01

    An analytical expression of the Voigt integral, derived by numerical methods, is proposed. It spans a wide range in X-ray spectral region in which the Lorentzian broadening of atomic origin and the Gaussian (instrumental) broadenings are of comparable magnitude. The indefinite integral of this expression is easy to evaluate and provide a good approximation for the X-ray threshold profiles. The proposed expressions are compared with previously proposed Voigt profiles and an example of experimental data analysis by fitting the lines and threshold profiles is given. ((orig.))

  9. Experimental analysis of temperature profiles in ceramic brickwork elements subjected to high temperatures

    Directory of Open Access Journals (Sweden)

    Maciá, M. E.

    2013-12-01

    Full Text Available This article discusses heat transfer through a brick element in order to know the thermal behavior of onedimensional brickwork masonry samples exposed to high temperatures. The object of the tests is to build time-temperature curves according to different thermal steps in transient to experimentally determine the temperature profiles in the interior of a wall. Through this study, it is possible to demonstrate absolute moisture of a factory item from 300 °C (variation of temperatures in the interior of the element, avoid the associated phenomenon of evaporation of water during the thermal process as well as to obtain profiles of temperatures that help calculate the cross section of a factory element subjected to high temperatures.En este artículo se analiza la transferencia de calor a través de un elemento de fábrica de ladrillo con el fin de conocer el comportamiento térmico de secciones de fábrica unidimensionales expuestas a altas temperaturas. El objeto de los ensayos es construir curvas tiempo-temperatura en función de diversos escalones térmicos en régimen transitorio para determinar experimentalmente los perfiles de temperatura en el interior de un muro. A través de este estudio es posible evidenciar el contenido de humedad absoluta de un elemento de fábrica a partir de los 300 ºC (variación de las temperaturas en el interior del elemento, evitar el fenómeno asociado de la evaporación del agua durante el proceso térmico así como obtener perfiles de temperaturas que ayuden a calcular la sección eficaz de un elemento de fábrica sometido a altas temperaturas.

  10. Bootstrap current simulations with experimental LHD plasma density and temperature profiles, energy scattering and finite orbit width

    International Nuclear Information System (INIS)

    Bootstrap current calculations with the neoclassical SPBSC and VENUS+δf codes have been performed on experimental Large Helical Device (LHD, NIFS, Japan) configurations with different magnetic axis positions and simplified plasma density and temperature profiles. In this paper, we use experimentally obtained electron density and temperature profiles for the LHD discharges no.61863 and no.82582 to compute the corresponding magnetohydrodynamic equilibrium states and collisional frequency. An improved collisional operator has been implemented into the VENUS+δf code. The comparison between the measured LHD bootstrap current and that expected from neoclassical simulations is discussed. (author)

  11. Comprehensive comparison and experimental validation of band-structure calculation methods in III-V semiconductor quantum wells

    Science.gov (United States)

    Zerveas, George; Caruso, Enrico; Baccarani, Giorgio; Czornomaz, Lukas; Daix, Nicolas; Esseni, David; Gnani, Elena; Gnudi, Antonio; Grassi, Roberto; Luisier, Mathieu; Markussen, Troels; Osgnach, Patrik; Palestri, Pierpaolo; Schenk, Andreas; Selmi, Luca; Sousa, Marilyne; Stokbro, Kurt; Visciarelli, Michele

    2016-01-01

    We present and thoroughly compare band-structures computed with density functional theory, tight-binding, k · p and non-parabolic effective mass models. Parameter sets for the non-parabolic Γ, the L and X valleys and intervalley bandgaps are extracted for bulk InAs, GaAs and InGaAs. We then consider quantum-wells with thickness ranging from 3 nm to 10 nm and the bandgap dependence on film thickness is compared with experiments for In0.53Ga0.47 As quantum-wells. The impact of the band-structure on the drain current of nanoscale MOSFETs is simulated with ballistic transport models, the results provide a rigorous assessment of III-V semiconductor band structure calculation methods and calibrated band parameters for device simulations.

  12. Comparison of the electronic band profiles and magneto-optic properties of cubic and orthorhombic SrTbO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Zahid, E-mail: zahidf82@gmail.com [Materials Modeling Center, Department of Physics, University of Malakand, Chakdara (Pakistan); Khan, Imad; Ahmad, Iftikhar [Materials Modeling Center, Department of Physics, University of Malakand, Chakdara (Pakistan); Naeem, S. [Department of Physics, Islamia College University, Peshawar (Pakistan); Rahnamaye Aliabad, H.A. [Department of Physics, Hakim Savzevari University, Sabzevar (Iran, Islamic Republic of); Jalali Asadabadi, S. [Department of Physics, Faculty of Science, University of Isfahan, Hezar Gerib Avenue, Isfahan 81744 (Iran, Islamic Republic of); Zhang, D. [Department of Physics, California State University, Fresno (United States)

    2013-08-15

    The all electrons full potential linearized augmented plane waves (FP-LAPW) method with GGA+U is used to study SrTbO{sub 3} perovskite in cubic and orthorhombic phases. The structural parameters and ground state magnetic properties are found consistent with the experimental results. The electronic band structures and density of states demonstrate that SrTbO{sub 3} is a wide band gap semiconductor in both phases. The magnetic studies of the material show that the nature of the compound is G-type anti-ferromagnetic. The calculated magnetic moment of Tb{sup +4} is found consistent with the experiments. Furthermore, the optical properties demonstrate that the optical gap of the material is 1.8 eV, which lies in the visible region of the electromagnetic spectrum and hence the compound can be used in optoelectronic devices.

  13. Photonic band gap materials

    International Nuclear Information System (INIS)

    An overview of the theoretical and experimental efforts in obtaining a photonic band gap, a frequency band in three-dimensional dielectric structures in which electromagnetic waves are forbidden, is presented

  14. Experimental confirmation of calculated phases and electron density profile for wet native collagen.

    Science.gov (United States)

    Stinson, R H; Bartlett, M W; Kurg, T; Sweeny, P R; Hendricks, R W

    1979-01-01

    An experimental procedure is developed to phase the reflections obtained in x-ray diffraction investigations of collagen in native wet tendons. Phosphotungstic acid was used for isomorphous addition in phase determination and was located by electron microscopy. Structure factors (with phases) were obtained from the electron microscopy data for the heavy metal. Structure-factor magnitudes for collagen with and without the heavy metal were obtained from the x-ray diffraction data. The first 10 orders were investigated. Standard Argand diagrams provided two solutions for each of these, except the weak sixth order. In each case, one of the two possible solutions agrees well with the phases proposed on theoretical grounds by Hulmes et al. The present results suggest that their other proposed phases are probably correct. An electron density profile along the unit cell of the fibril is presented that shows a distinct step, as expected on the basis of the hole-overlap model. The overlap region is 48% of the length of the unit cell. Images FIGURE 2 PMID:262416

  15. Biochemical profile of dogs experimentally envenomed with Tityus serrulatus scorpion venom.

    Science.gov (United States)

    Ribeiro, E L; Pinto, M C L; Labarrère, C R; Paes, P R O; Paes-Leme, F O; Chávez-Olórtegui, C; Melo, M M

    2010-06-01

    The aim of this study was to evaluate the canine blood and urinary profiles after envenomation by Tityus serrulatus venom. Twelve dogs were randomly distributed into two equal groups. Control group animals received 0.5 mL phosphate buffered saline (PBS) injected subcutaneously into the internal portion of the left thigh, whilst dogs in the envenomed group were injected with scorpion venom (250 microg/kg in 0.5 mL PBS). No significant alterations were detected in the urine of envenomed dogs. Levels of plasma glucose and serum urea, creatinine, total protein, potassium, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase (CK), lactate dehydrogenase (LDH), and amylase were determined. Semi-quantitative analysis of serum cardiac troponin I (cTnI) was performed using an immunochromatographic test. The concentrations of cortisol and insulin were determined using commercial radioimmunoassay kits. Increases in serum cortisol levels in experimental group animals coincided with hyperglycaemia and was probably a response to pain. Increased insulin levels were observed during the hyperglycaemic peaks. Envenomed dogs presented discreet increases in ALT, AST and CK, but no alterations in LDH, amylase, cTnI, urea, creatinine and potassium levels were observed. It was concluded that the venom of T. serrulatus induces blood and urinary biochemical changes in dogs. PMID:20060404

  16. Imaging of the Deep Structure by Long Term Broad Band OBSs \\ \\ -- Trans-PHS Profile and NW Pacific WP-2 site --

    Science.gov (United States)

    Shiobara, H.; Sugioka, H.; Yoneshima, S.; Mochizuki, K.; Mochizuki, M.; Kodaira, S.; Hino, R.; Shinohara, M.; Kanazawa, T.; Fukao, Y.

    2001-12-01

    As an important part of the Ocean Hemisphere network Project, long term ocean bottom seismic observations have been started and some of their data have been retrieved already. One of them, the trans-Philippine Sea profile observation (15 Long Term OBSs, Nov. 1999 -- July 2000) was preliminarily reported at the last AGU fall meeting (S51B-02, 2000). Other long term broad band observations had been performed twice at the northwestern Pacific (Broad Band OBS, NWPAC1: Aug. 1999 -- May 2000, NWPAC2: May 2000 -- Nov. 2000), where the borehole seismic observatory (WP-2) has been activated in Nov. 2000. The LTOBS and the BBOBS contain a semi broad band sensor (WB2023LP, PMD) which has the pass band from 30s to 50Hz and a broad band sensor (CMG-1T, Guralp) which has the pass band from 360s to 80Hz, respectively. The seismic data is recorded continuously with a sampling frequency of 128Hz by a 20bit ADC on four 2.5 inch 6.5 GB HDDs. The direction of horizontal components are determined from the data of the direct water wave during the airgun shooting or P-SV converted waves at the sediment-basement interface. Running acceleration power spectra (0dB=1m2/s4/Hz) of these data during the whole observation period indicate followings; 1) sufficiently low noise band exists in the frequency range of 10--100mHz and the lowest level is close to the NLNM, but the horizontal noise level varies about 20--30dB with a dominant 12 hours interval, 2) high level micro seismic noise in the range of 0.1--1Hz is always near the NHNM and varies about 30--40dB. In this presentation, preliminary results of the deep structure imaging from these vast data by a receiver function analysis is shown. To perform this analysis with the OBS data, removal of water column reverberations and reduction of high level micro seismic noise should be necessary. The former process has a difficulty in the estimation of the water-sea bottom reflection coefficient and requires the data of higher sampling frequency, more

  17. Valence and Conduction Band Densities of States of Metal Halide Perovskites: A Combined Experimental-Theoretical Study.

    Science.gov (United States)

    Endres, James; Egger, David A; Kulbak, Michael; Kerner, Ross A; Zhao, Lianfeng; Silver, Scott H; Hodes, Gary; Rand, Barry P; Cahen, David; Kronik, Leeor; Kahn, Antoine

    2016-07-21

    We report valence and conduction band densities of states measured via ultraviolet and inverse photoemission spectroscopies on three metal halide perovskites, specifically methylammonium lead iodide and bromide and cesium lead bromide (MAPbI3, MAPbBr3, CsPbBr3), grown at two different institutions on different substrates. These are compared with theoretical densities of states (DOS) calculated via density functional theory. The qualitative agreement achieved between experiment and theory leads to the identification of valence and conduction band spectral features, and allows a precise determination of the position of the band edges, ionization energy and electron affinity of the materials. The comparison reveals an unusually low DOS at the valence band maximum (VBM) of these compounds, which confirms and generalizes previous predictions of strong band dispersion and low DOS at the MAPbI3 VBM. This low DOS calls for special attention when using electron spectroscopy to determine the frontier electronic states of lead halide perovskites. PMID:27364125

  18. Experimental and theoretical investigations of the electronic band structure of metal-organic frameworks of HKUST-1 type

    International Nuclear Information System (INIS)

    The electronic properties of metal-organic frameworks (MOFs) are increasingly attracting the attention due to potential applications in sensor techniques and (micro-) electronic engineering, for instance, as low-k-dielectric in semiconductor technology. Here, the band gap and the band structure of MOFs of type HKUST-1 are studied in detail by means of spectroscopic ellipsometry applied to thin surface-mounted MOF films and by means of quantum chemical calculations. The analysis of the density of states, the band structure, and the excitation spectrum reveal the importance of the empty Cu-3d orbitals for the electronic properties of HKUST-1. This study shows that, in contrast to common belief, even in the case of this fairly “simple” MOF, the excitation spectra cannot be explained by a superposition of “intra-unit” excitations within the individual building blocks. Instead, “inter-unit” excitations also have to be considered

  19. Experimental and theoretical investigations of the electronic band structure of metal-organic frameworks of HKUST-1 type

    Science.gov (United States)

    Gu, Zhi-Gang; Heinke, Lars; Wöll, Christof; Neumann, Tobias; Wenzel, Wolfgang; Li, Qiang; Fink, Karin; Gordan, Ovidiu D.; Zahn, Dietrich R. T.

    2015-11-01

    The electronic properties of metal-organic frameworks (MOFs) are increasingly attracting the attention due to potential applications in sensor techniques and (micro-) electronic engineering, for instance, as low-k-dielectric in semiconductor technology. Here, the band gap and the band structure of MOFs of type HKUST-1 are studied in detail by means of spectroscopic ellipsometry applied to thin surface-mounted MOF films and by means of quantum chemical calculations. The analysis of the density of states, the band structure, and the excitation spectrum reveal the importance of the empty Cu-3d orbitals for the electronic properties of HKUST-1. This study shows that, in contrast to common belief, even in the case of this fairly "simple" MOF, the excitation spectra cannot be explained by a superposition of "intra-unit" excitations within the individual building blocks. Instead, "inter-unit" excitations also have to be considered.

  20. Experimental and theoretical investigations of the electronic band structure of metal-organic frameworks of HKUST-1 type

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Zhi-Gang [Institut für Funktionelle Grenzflächen (IFG), Karlsruher Institut für Technologie (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 350002 Fuzhou (China); Heinke, Lars, E-mail: Lars.Heinke@KIT.edu; Wöll, Christof [Institut für Funktionelle Grenzflächen (IFG), Karlsruher Institut für Technologie (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Neumann, Tobias; Wenzel, Wolfgang; Li, Qiang; Fink, Karin [Institute of Nanotechnology (INT), Karlsruher Institut für Technologie (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Gordan, Ovidiu D.; Zahn, Dietrich R. T. [Semiconductor Physics, Technische Universität Chemnitz, 09107 Chemnitz (Germany)

    2015-11-02

    The electronic properties of metal-organic frameworks (MOFs) are increasingly attracting the attention due to potential applications in sensor techniques and (micro-) electronic engineering, for instance, as low-k-dielectric in semiconductor technology. Here, the band gap and the band structure of MOFs of type HKUST-1 are studied in detail by means of spectroscopic ellipsometry applied to thin surface-mounted MOF films and by means of quantum chemical calculations. The analysis of the density of states, the band structure, and the excitation spectrum reveal the importance of the empty Cu-3d orbitals for the electronic properties of HKUST-1. This study shows that, in contrast to common belief, even in the case of this fairly “simple” MOF, the excitation spectra cannot be explained by a superposition of “intra-unit” excitations within the individual building blocks. Instead, “inter-unit” excitations also have to be considered.

  1. Tsunami Affected Farmland Extraction Using Morphological Profiles (MPs) Method by Satellite Images Including SAR and Visible Near-Infrared Band Data

    Science.gov (United States)

    Yamada, Y.

    2015-04-01

    The agricultural fields along the coast were submerged under the sea water after the 2011 off the Pacific Coast of Tohoku Japan Tsunami. The conventional method of detecting Tsunami reached area by SAR satellite data is to compare the data obtained between previous to and after the Tsunami. However such kind of SAR data should be prepared prior to the natural disaster, but in many disaster cases, people have often encountered difficulties in finding such kind of data observed in advance in some regions. Therefore it is desirable to find a way to detect the flood suffering farmlands caused by a Tsunami, using only data observed after the disaster event. The morphological profiles (MPs) method are tested using ALOS/PALSAR and AVNIR-2 data. This MPs method is proposed as the tool for extracting information about the size, shape and the orientation of structures in single-band remote sensing images and has been improved to establish the extended morphological profiles(EMP) dealing with full-spectral information in the multi-/hyper-spectral data (Benediktsson, J.A. et al.,2003,2005). The author's work is intended to apply this MPs method to combined single polarization SAR data and visual and near-infrared bands data. The results approximately coincide with the farmland regions actually reached by the Tsunami. This MPs method requires only data once obtained soon after a disaster, light computer resources and very short turnaround time. It should be suitable for the detection of Tsunami reached areas or tidal wave reached areas, caused by a Typhoon for example, using satellite data only once obtained after a disaster.

  2. Towards DIB mapping in galaxies beyond 100 Mpc. A radial profile of the $\\lambda$5780.5 diffuse interstellar band in AM 1353-272 B

    CERN Document Server

    Monreal-Ibero, Ana; Wendt, Martin; Selman, Fernando; Lallement, Rosine; Brinchmann, Jarle; Kamann, Sebastian; Sandin, Christer

    2015-01-01

    Diffuse Interstellar Bands (DIBs) are non-stellar weak absorption features of unknown origin found in the spectra of stars viewed through one or several clouds of Interstellar Medium (ISM). Research of DIBs outside the Milky Way is currently very limited. Specifically spatially resolved investigations of DIBs outside of the Local Group is, to our knowledge, inexistent. Here, we explore the capability of the high sensitivity Integral Field Spectrograph, MUSE, as a tool to map diffuse interstellar bands at distances larger than 100 Mpc. We use MUSE commissioning data for AM 1353-272 B, the member with highest extinction of the "The Dentist's Chair", an interacting system of two spiral galaxies. High signal-to-noise spectra were created by co-adding the signal of many spatial elements distributed in a geometry of concentric elliptical half-rings. We derived decreasing radial profiles for the equivalent width of the $\\lambda$5780.5 DIB both in the receding and approaching side of the companion galaxy up to distan...

  3. Metabolomic profiling in cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Jeroen De Buck

    Full Text Available The sensitivity of current diagnostics for Johne's disease, a slow, progressing enteritis in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP, is too low to reliably detect all infected animals in the subclinical stage. The objective was to identify individual metabolites or metabolite profiles that could be used as biomarkers of early MAP infection in ruminants. In a monthly follow-up for 17 months, calves infected at 2 weeks of age were compared with aged-matched controls. Sera from all animals were analyzed by 1H nuclear magnetic resonance spectrometry. Spectra were acquired, processed, and quantified for analysis. The concentration of many metabolites changed over time in all calves, but some metabolites only changed over time in either infected or non-infected groups and the change in others was impacted by the infection. Hierarchical multivariate statistical analysis achieved best separation between groups between 300 and 400 days after infection. Therefore, a cross-sectional comparison between 1-year-old calves experimentally infected at various ages with either a high- or a low-dose and age-matched non-infected controls was performed. Orthogonal Projection to Latent Structures Discriminant Analysis (OPLS DA yielded distinct separation of non-infected from infected cattle, regardless of dose and time (3, 6, 9 or 12 months after infection. Receiver Operating Curves demonstrated that constructed models were high quality. Increased isobutyrate in the infected cattle was the most important agreement between the longitudinal and cross-sectional analysis. In general, high- and low-dose cattle responded similarly to infection. Differences in acetone, citrate, glycerol and iso-butyrate concentrations indicated energy shortages and increased fat metabolism in infected cattle, whereas changes in urea and several amino acids (AA, including the branched chain AA, indicated increased protein turnover. In conclusion, metabolomics

  4. Improved profile fitting and quantification of uncertainty in experimental measurements of impurity transport coefficients using Gaussian process regression

    International Nuclear Information System (INIS)

    The need to fit smooth temperature and density profiles to discrete observations is ubiquitous in plasma physics, but the prevailing techniques for this have many shortcomings that cast doubt on the statistical validity of the results. This issue is amplified in the context of validation of gyrokinetic transport models (Holland et al 2009 Phys. Plasmas 16 052301), where the strong sensitivity of the code outputs to input gradients means that inadequacies in the profile fitting technique can easily lead to an incorrect assessment of the degree of agreement with experimental measurements. In order to rectify the shortcomings of standard approaches to profile fitting, we have applied Gaussian process regression (GPR), a powerful non-parametric regression technique, to analyse an Alcator C-Mod L-mode discharge used for past gyrokinetic validation work (Howard et al 2012 Nucl. Fusion 52 063002). We show that the GPR techniques can reproduce the previous results while delivering more statistically rigorous fits and uncertainty estimates for both the value and the gradient of plasma profiles with an improved level of automation. We also discuss how the use of GPR can allow for dramatic increases in the rate of convergence of uncertainty propagation for any code that takes experimental profiles as inputs. The new GPR techniques for profile fitting and uncertainty propagation are quite useful and general, and we describe the steps to implementation in detail in this paper. These techniques have the potential to substantially improve the quality of uncertainty estimates on profile fits and the rate of convergence of uncertainty propagation, making them of great interest for wider use in fusion experiments and modelling efforts. (paper)

  5. Experimental validation of the band-gap and dispersive bulk modulus behaviour of locally resonant acoustic metamaterials

    OpenAIRE

    Reynolds, Matthew; Gao, Yan; Daley, Stephen

    2013-01-01

    Over the last decade there has been significant interest in the design and production of acoustic metamaterials with physical qualities not seen in naturally occurring media. Progress in this area has been stimulated by the desire to create materials that exhibit novel behaviour such as negative refraction due to negative material parameters, and band gaps in the frequency response of the material. An acoustic metamaterial is presented that consists of an acoustically transparent mesh with an...

  6. Experimental Demonstration of a Hybrid-Quantum-Emitter Producing Individual Entangled Photon Pairs in the Telecom Band

    Science.gov (United States)

    Chen, Geng; Zou, Yang; Zhang, Wen-Hao; Zhang, Zi-Huai; Zhou, Zong-Quan; He, De-Yong; Tang, Jian-Shun; Liu, Bi-Heng; Yu, Ying; Zha, Guo-Wei; Ni, Hai-Qiao; Niu, Zhi-Chuan; Han, Yong-Jian; Li, Chuan-Feng; Guo, Guang-Can

    2016-05-01

    Quantum emitters generating individual entangled photon pairs (IEPP) have significant fundamental advantages over schemes that suffer from multiple photon emission, or schemes that require post-selection techniques or the use of photon-number discriminating detectors. Quantum dots embedded within nanowires (QD-NWs) represent one of the most promising candidate for quantum emitters that provide a high collection efficiency of photons. However, a quantum emitter that generates IEPP in the telecom band is still an issue demanding a prompt solution. Here, we demonstrate in principle that IEPPs in the telecom band can be created by combining a single QD-NW and a nonlinear crystal waveguide. The QD-NW system serves as the single photon source, and the emitted visible single photons are split into IEPPs at approximately 1.55 μm through the process of spontaneous parametric down conversion (SPDC) in a periodically poled lithium niobate (PPLN) waveguide. The compatibility of the QD-PPLN interface is the determinant factor in constructing this novel hybrid-quantum-emitter (HQE). Benefiting from the desirable optical properties of QD-NWs and the extremely high nonlinear conversion efficiency of PPLN waveguides, we successfully generate IEPPs in the telecom band with the polarization degree of freedom. The entanglement of the generated photon pairs is confirmed by the entanglement witness. Our experiment paves the way to producing HQEs inheriting the advantages of multiple systems.

  7. Experimental Demonstration of a Hybrid-Quantum-Emitter Producing Individual Entangled Photon Pairs in the Telecom Band.

    Science.gov (United States)

    Chen, Geng; Zou, Yang; Zhang, Wen-Hao; Zhang, Zi-Huai; Zhou, Zong-Quan; He, De-Yong; Tang, Jian-Shun; Liu, Bi-Heng; Yu, Ying; Zha, Guo-Wei; Ni, Hai-Qiao; Niu, Zhi-Chuan; Han, Yong-Jian; Li, Chuan-Feng; Guo, Guang-Can

    2016-01-01

    Quantum emitters generating individual entangled photon pairs (IEPP) have significant fundamental advantages over schemes that suffer from multiple photon emission, or schemes that require post-selection techniques or the use of photon-number discriminating detectors. Quantum dots embedded within nanowires (QD-NWs) represent one of the most promising candidate for quantum emitters that provide a high collection efficiency of photons. However, a quantum emitter that generates IEPP in the telecom band is still an issue demanding a prompt solution. Here, we demonstrate in principle that IEPPs in the telecom band can be created by combining a single QD-NW and a nonlinear crystal waveguide. The QD-NW system serves as the single photon source, and the emitted visible single photons are split into IEPPs at approximately 1.55 μm through the process of spontaneous parametric down conversion (SPDC) in a periodically poled lithium niobate (PPLN) waveguide. The compatibility of the QD-PPLN interface is the determinant factor in constructing this novel hybrid-quantum-emitter (HQE). Benefiting from the desirable optical properties of QD-NWs and the extremely high nonlinear conversion efficiency of PPLN waveguides, we successfully generate IEPPs in the telecom band with the polarization degree of freedom. The entanglement of the generated photon pairs is confirmed by the entanglement witness. Our experiment paves the way to producing HQEs inheriting the advantages of multiple systems. PMID:27225881

  8. Transcriptional Profiling of Hilar Nodes from Pigs after Experimental Infection with Actinobacillus Pleuropneumoniae

    Directory of Open Access Journals (Sweden)

    Shumin Yu

    2013-11-01

    Full Text Available The gram-negative bacterium Actinobacillus pleuropneumoniae (APP is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP. In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE at the p ≤ 0.01 level by comparing the log2 (normalized signal of the two groups named treatment group (TG and controls (CG. Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB. Two hundred and seventy-two biological process categories (BP, 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway. Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform, mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were

  9. Experimental demonstration of low-complexity fiber chromatic dispersion mitigation for reduced guard-interval OFDM coherent optical communication systems based on digital spectrum sub-band multiplexing.

    Science.gov (United States)

    Malekiha, Mahdi; Tselniker, Igor; Nazarathy, Moshe; Tolmachev, Alex; Plant, David V

    2015-10-01

    We experimentally demonstrate a novel digital signal processing (DSP) structure for reduced guard-interval (RGI) OFDM coherent optical systems. The proposed concept is based on digitally slicing optical channel bandwidth into multiple spectrally disjoint sub-bands which are then processed in parallel. Each low bandwidth sub-band has a smaller delay-spread compared to a full-band signal. This enables compensation of both chromatic dispersion (CD) and polarization mode dispersion using a simple timing and one-tap-per-symbol frequency domain equalizer with a small cyclic prefix overhead. In terms of the DSP architecture, this allows for a highly efficient parallelization of DSP tasks performed over the received signal samples by deploying multiple processors running at a lower clock rate. It should be noted that this parallelization is performed in the frequency domain and it allows for flexible optical transceiver schemes. In addition, the resulting optical receiver is simplified due to the removal of the CD compensation equalizer compared to conventional RGI-OFDM systems. In this paper we experimentally demonstrate digital sub-banding of optical bandwidth. We test the system performance for different modulation formats (QPSK, 16QAM and 32QAM) over various transmission distances and optical launch powers using a 1.5% CP overhead in all scenarios. We also compare the proposed RGI-OFDM architecture performance against common single carrier modulation formats. At the same total data rate and signal bandwidth both systems have similar performance and transmission reach whereas the proposed method allows for a significant reduction of computational complexity due to removal of CD pre/post compensation equalizer. PMID:26480077

  10. Experimental investigation on wake profile detection based on laser scattering by bubbles

    Institute of Scientific and Technical Information of China (English)

    Liping Su; Weijiang Zhao; Xiaoyong Hu; Deming Ren; Xizhan Liu

    2007-01-01

    @@ The optical system for detecting wake profiles based on laser backscattering by bubbles at 180° is reported, in which the monostatic optical geometry is adopted and the power density estimation is used to process bubble scattering signal.

  11. Seismic Behaviour of an Experimental Model Made of Thin-Walled Cold Formed Steel Profiles - Hardell Structures

    Directory of Open Access Journals (Sweden)

    Ionuţ-Ovidiu Toma

    2009-01-01

    Full Text Available The experimental results of the shaking table test of a Hardell structure made of thin-walled cold formed steel profiles are presented. The structure has the in-plane dimensions of 4x4 m and a height of 6 m, being classified as a P+1E type of structure. The dynamic characteristics of the structure were determined during the first stage of the experiment. Afterwards, the structure was subjected to different types of dynamic loadings such as sine-sweep functions and to seismic actions simulating the El Centro and Vrancea earthquakes. The damages induced by the seismic excitations consisted of local buckling of the steel profiles and breaking of two anchorage bolts holding the structure to the shaking table. Based on the experimental results it can be concluded that the structure can safely withstand seismic loads up to certain intensity, provided that some requirements are met.

  12. A Radiative Performance Investigation of the PLIF Experimental and Theoretical Large Diameter Argon Gas Puff Nozzle Profiles on DQ

    Science.gov (United States)

    Chong, Y. K.; Thornhill, J. W.; Davis, J.; Qi, N.; Frese, M. H.; Frese, S. D.

    2004-11-01

    Theoretical and experimental results for the dynamics and the K-shell radiation emission characteristics of large diameter argon double-puff loads driven by the Decade Quad (DQ) pulsed power generator are compared. The theoretical results are generated using a version of the MACH2 two dimensional MHD code that incorporates a tabular collisional radiative equilibrium (TCRE) model. The TCRE model is needed to self-consistently treat the non-LTE radiation and ionization dynamics. The initial gas density profiles used in the calculations are taken from the measured PLIF (planar laser induced fluorescence) data. Based on the results of this experimental/theoretical comparison, it may be possible to create a theoretical tool for designing future nozzles. This can be done by combining the capabilities of our radiation MHD code with one that does a reasonable job of predicting the initial density profile for a given nozzle such as the Navier Stokes nozzle design code at AEDC.

  13. Resistance Training Improves Hemodynamic Function, Collagen Deposition and Inflammatory Profiles: Experimental Model of Heart Failure

    OpenAIRE

    Alves, Jadson P.; Nunes, Ramiro B.; Stefani, Giuseppe P.; Dal Lago, Pedro

    2014-01-01

    The role of resistance training on collagen deposition, the inflammatory profile and muscle weakness in heart failure remains unclear. Therefore, this study evaluated the influence of a resistance training program on hemodynamic function, maximum strength gain, collagen deposition and inflammatory profile in chronic heart failure rats. Thirty-two male Wistar rats submitted to myocardial infarction by coronary artery ligation or sham surgery were assigned into four groups: sedentary sham (S-Sh...

  14. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  15. Cu–Zn disorder and band gap fluctuations in Cu2ZnSn(S,Se)4 : Theoretical and experimental investigations

    OpenAIRE

    Scragg, Jonathan; Larsen, Jes; Kumar, Mukesh; Persson, Clas; Sendler, Jan; Siebentritt, Susanne; Platzer-Björkman, Charlotte

    2016-01-01

    Cu2ZnSn(S,Se)4 (CZTS(e)) solar cells suffer from low-open-circuit voltages that have been blamed on the existence of band gap fluctuations, with different possible origins. In this paper, we show from both theoretical and experimental standpoints that disorder of Cu and Zn atoms is in all probability the primary cause of these fluctuations. First, quantification of Cu–Zn disorder in CZTS thin films is presented. The results indicate that disorder is prevalent in the majority of practical samp...

  16. Experimental approach to shape field relevant blast wave profiles in compressed gas-driven shock tube

    Directory of Open Access Journals (Sweden)

    Aravind eSundaramurthy

    2014-12-01

    Full Text Available Detonation of a high explosive produces shock-blast wave, shrapnel, and gaseous products. While direct exposure to blast is a concern near the epicenter, shock-blast can affect subjects even at farther distances, which is termed as primary blast injury, which is the theme of this work. The shock-blast profile is characterized with blast overpressure, positive time duration, and impulse as shock-blast wave parameters (SWPs. These parameters in turn are a function of field factors, such as the strength of high explosive and the distance of the human subjects from the epicenter. The shape and magnitude of the profile determine the severity of injury to the subjects. As shown in some of our recent works (Chandra et al., 2011;Sundaramurthy et al., 2012;Skotak et al., 2013, the profile not only determines the survival of the animal but also the acute and chronic biomechanical injuries along with the following bio-chemical sequelae. It is extremely important to carefully design and operate the shock tube to produce field relevant SWPs. Furthermore, it is vital to identify and eliminate the artifacts that are inadvertently introduced in the shock-blast profile that may affect the results. In this work, we examine the relationship between shock tube adjustable parameters (SAPs and SWPs that can be used to control the blast profile; the results can be easily applied to many of the laboratory shock tubes. Further, exact replication of shock profile (magnitude and shape can be related to field explosions and can be a standard in comparing results across different laboratories. 40 experiments are carried out by judiciously varying SAPs such as membrane thickness, breech length (66.68 to 1209.68 mm, measurement location, and type of driver gas (nitrogen, helium. The relationships between SAPs and the resulting shock-blast profiles are characterized. Finally, shock-blast profiles of a TNT explosion from ConWep software is compared with the profiles obtained

  17. Experimental evaluation of ground-based microwave radiometric sensing of atmospheric temperature and water vapor profiles

    International Nuclear Information System (INIS)

    Profiles of atmospheric temperature and water vapor derived from ground-based microwave radiometric measurements are compared with concurrent rawinsonde profiles including both clear and cloudy cases. Accuracies of the temperature profiles including the cloudy cases are quite close to predicted accuracies. Mean virtual temperatures between commonly used pressure levels are also compared and resulting rms accuracies are 1.1, 1.6, 2.0 and 2.80C for the 1000--850, 850--700, 700--500 and 500--300 mb layers, respectively. The microwave technique is potentially useful in applications requiring high time resolution or in data-sparse regions of the oceans that might be covered by an ocean data buoy system

  18. Final Technical Report: Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Eugenio

    2014-05-02

    The strong coupling between the different physical variables involved in the plasma transport phenomenon and the high complexity of its dynamics call for a model-based, multivariable approach to profile control where those predictive models could be exploited. The overall objective of this project has been to extend the existing body of work by investigating numerically and experimentally active control of unstable fluctuations, including fully developed turbulence and the associated cross-field particle transport, via manipulation of flow profiles in a magnetized laboratory plasma device. Fluctuations and particle transport can be monitored by an array of electrostatic probes, and Ex B flow profiles can be controlled via a set of biased concentric ring electrodes that terminate the plasma column. The goals of the proposed research have been threefold: i- to develop a predictive code to simulate plasma transport in the linear HELCAT (HELicon-CAThode) plasma device at the University of New Mexico (UNM), where the experimental component of the proposed research has been carried out; ii- to establish the feasibility of using advanced model-based control algorithms to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles, iii- to investigate the fundamental nonlinear dynamics of turbulence and transport physics. Lehigh University (LU), including Prof. Eugenio Schuster and one full-time graduate student, has been primarily responsible for control-oriented modeling and model-based control design. Undergraduate students have also participated in this project through the National Science Foundation Research Experience for Undergraduate (REU) program. The main goal of the LU Plasma Control Group has been to study the feasibility of controlling turbulence-driven transport by shaping the radial poloidal flow profile (i.e., by controlling flow shear) via biased concentric ring electrodes.

  19. The Experimental Study on Wide-band Tunable All-fiber Acousto-optic Filter Based on Null Coupler

    Institute of Scientific and Technical Information of China (English)

    LI Tong; LI Qun; LIU Dan; LIU Xiaoming; PENG Jiangde

    2000-01-01

    The fiber acousto-optic filter is fabricated successfully for the first time in China. The mode conversion is realized by the acoustic-wave induced perturbation. Excess loss of 0.1 dB and continuous tuning range between 1470 nm and 1580 nm are obtained. The polarization dependence of the filter is studied experimentally.

  20. Transcriptome of Treponema pallidum: Gene Expression Profile during Experimental Rabbit Infection†

    OpenAIRE

    Šmajs, David; McKevitt, Matthew; Howell, Jerrilyn K.; Norris, Steven J; Cai, Wei-Wen; Palzkill, Timothy; Weinstock, George M.

    2005-01-01

    RNA transcript levels in the syphilis spirochete Treponema pallidum subsp. pallidum (Nichols) isolated from experimentally infected rabbits were determined by the use of DNA microarray technology. This characterization of the T. pallidum transcriptome during experimental infection provides further insight into the importance of gene expression levels for the survival and pathogenesis of this bacterium.

  1. Voigt deconvolution method and its applications to pure oxygen absorption spectrum at 1270 nm band

    Science.gov (United States)

    AL-Jalali, Muhammad A.; Aljghami, Issam F.; Mahzia, Yahia M.

    2016-03-01

    Experimental spectral lines of pure oxygen at 1270 nm band were analyzed by Voigt deconvolution method. The method gave a total Voigt profile, which arises from two overlapping bands. Deconvolution of total Voigt profile leads to two Voigt profiles, the first as a result of O2 dimol at 1264 nm band envelope, and the second from O2 monomer at 1268 nm band envelope. In addition, Voigt profile itself is the convolution of Lorentzian and Gaussian distributions. Competition between thermal and collisional effects was clearly observed through competition between Gaussian and Lorentzian width for each band envelope. Voigt full width at half-maximum height (Voigt FWHM) for each line, and the width ratio between Lorentzian and Gaussian width (ΓLΓG- 1) have been investigated. The following applied pressures were at 1, 2, 3, 4, 5, and 8 bar, while the temperatures were at 298 K, 323 K, 348 K, and 373 K range.

  2. Experimental study of a W-band Gyroklystron amplifier operated in the high-order TE021 cavity mode

    Science.gov (United States)

    Zasypkin, E. V.; Gachev, I. G.; Antakov, I. I.

    2012-10-01

    We present experimental results for a 93.2-GHz gyroklystron amplifier operated in the high-order TE021 cavity mode in a cryomagnet. In a three-cavity gyroklystron, a peak output power of 340 kW with 27% efficiency, 23-dB saturated gain, and 0.41% (380 MHz) bandwidth was obtained with a 75-kV, 17-A electron beam. The output-power and efficiency restriction was due to the selfexcitation of the TE021 operating mode in the output cavity. The influence of the electron beam current and intermediate cavity Q-factor on output characteristics of a three-cavity gyroklystron has been studied experimentally.

  3. Experimental analysis of bruises in human volunteers using radiometric depth profiling and diffuse reflectance spectroscopy

    Science.gov (United States)

    Vidovič, Luka; Milanič, Matija; Majaron, Boris

    2015-07-01

    We combine pulsed photothermal radiometry (PPTR) depth profiling with diffuse reflectance spectroscopy (DRS) measurements for a comprehensive analysis of bruise evolution in vivo. While PPTR enables extraction of detailed depth distribution and concentration profiles of selected absorbers (e.g. melanin, hemoglobin), DRS provides information in a wide range of visible wavelengths and thus offers an additional insight into dynamics of the hemoglobin degradation products. Combining the two approaches enables us to quantitatively characterize bruise evolution dynamics. Our results indicate temporal variations of the bruise evolution parameters in the course of bruise self-healing process. The obtained parameter values and trends represent a basis for a future development of an objective technique for bruise age determination.

  4. Experimental measurements of selenium x-ray laser spectral line profiles

    Energy Technology Data Exchange (ETDEWEB)

    Koch, J.A.; MacGowan, B.J.; Da Silva, L.B.; Matthews, D.L.; London, R.A.; Lee, R.W.; Mrowka, S. [Lawrence Livermore National Lab., CA (US); Underwood, J.H.; Batson, P.J. [Lawrence Berkeley Lab., CA (US)

    1993-03-01

    The authors discuss their recent measurements of the spectral width of the 206.38 {Angstrom} x-ray laser transition in Ne-like Se. These measurements used a high-resolution grating spectrometer and were performed over a wide range of laser amplifier lengths. The data have enabled them to extrapolate the intrinsic line width and to observe the effects of gain-narrowing and saturation on the line profile. They find an intrinsic width which is 1.4 times the Doppler width, they observe gain-narrowing in intermediate length amplifiers, and they observe no re-broadening in long, saturated amplifiers. These results suggest that collisional line-broadening has a significant effect on the line profile and saturation behavior of this laser.

  5. Experimental and numerical results for CO2 concentration and temperature profiles in an occupied room

    Science.gov (United States)

    Cotel, Aline; Junghans, Lars; Wang, Xiaoxiang

    2014-11-01

    In recent years, a recognition of the scope of the negative environmental impact of existing buildings has spurred academic and industrial interest in transforming existing building design practices and disciplinary knowledge. For example, buildings alone consume 72% of the electricity produced annually in the United States; this share is expected to rise to 75% by 2025 (EPA, 2009). Significant reductions in overall building energy consumption can be achieved using green building methods such as natural ventilation. An office was instrumented on campus to acquire CO2 concentrations and temperature profiles at multiple locations while a single occupant was present. Using openFOAM, numerical calculations were performed to allow for comparisons of the CO2 concentration and temperature profiles for different ventilation strategies. Ultimately, these results will be the inputs into a real time feedback control system that can adjust actuators for indoor ventilation and utilize green design strategies. Funded by UM Office of Vice President for Research.

  6. Experimental Investigation of the Matching Relationship between Asphalt Particle and Reservoir Pore in Profile Control Process

    OpenAIRE

    Ren, Chengfeng; Li, Junjian; Li, Yiqiang; Yuan, Jingshu; Xi, Yanqiang; Xiao, Kang; Wang, Yuxi

    2016-01-01

    Modified sulfonated asphalt particles have a bright application prospect of the profile control of thick reservoirs due to the low cost, extensive sources, and good compatibility with reservoir. Nevertheless, the matching relationship between asphalt particles and reservoir pore has seldom been investigated till now. Oversized particles always block the near-wellbore area, which causes high injection pressures, while undersized particles cannot plug large pores. We designed a core for this ex...

  7. Experimental Research on Profile Control for Oil Displacement by Functional Polymer in Low Permeability Fractured Reservoir

    Science.gov (United States)

    Li, Li; Xiuting, Han; Lin, Meng

    Utilizing artificial fractured cores with low permeability, a physical simulation experiment on profile control for oil displacement was carried out. The result showed that 23.63% extra oil recovery was realized by functional polymer, and 29.05% extra oil recovery was realized by functional polymer with gas which is higher than water flooding alone. The experiment demonstrates that functional polymer is effective for enhance oil recovery for low permeability fractured reservoir significantly.

  8. Self-presentation and emotional contagion on Facebook: new experimental measures of profiles' emotional coherence

    OpenAIRE

    Guazzini, Andrea; Guidi, Elisa; Cecchini, Cristina; Milani, Monica; Vilone, Daniele; Meringolo, Patrizia

    2016-01-01

    Social Networks allow users to self-present by sharing personal contents with others which may add comments. Recent studies highlighted how the emotions expressed in a post affect others' posts, eliciting a congruent emotion. So far, no studies have yet investigated the emotional coherence between wall posts and its comments. This research evaluated posts and comments mood of Facebook profiles, analyzing their linguistic features, and a measure to assess an excessive self-presentation was int...

  9. Experimental characterization of two-dimensional spot profiles for two proton pencil beam scanning nozzles.

    Science.gov (United States)

    Lin, Liyong; Ainsley, Christopher G; Solberg, Timothy D; McDonough, James E

    2014-01-20

    Dose calculation for pencil beam scanning proton therapy requires accurate measurement of the broad tails of the proton spot profiles for every nozzle in clinical use. By applying a pair/magnification method and merging film data, 200 mm × 240 mm dose kernels extending to 10(-4) of the central spot dose are generated for six selected energies of the IBA dedicated and universal nozzles (DN and UN). One-dimensional, circular profiles up to 100 mm in radius are generated from the asymmetric profiles to facilitate spot profile comparison. For the highest energy, 225 MeV, the output of both the DN and the UN for field sizes from 40 to 200 mm increases in parallel, slowest at the surface (∼1%) and fastest at a depth of 150 mm (∼9%). In contrast, at the lowest energy, 100 MeV, the output of the DN across the same range of field sizes increases 3-4% versus 6-7% for the UN throughout all the depths. The charge deficits in the measured depth-dose of Bragg peaks are similar between the UN and the DN. At 100 MeV, the field size factor difference at the surface between two orientations of a rectangular 40 mm × 200 mm field is 1.4% at isocentre for the DN versus 2% for the UN. Though the one-dimensional distributions are similar for the primary and tail components at different positions, the primary components of the DN spots are more elliptical 270 mm upstream than at isocentre. PMID:24374943

  10. Global Metabolomic Profiling of Mice Brains following Experimental Infection with the Cyst-Forming Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Chun-Xue Zhou

    Full Text Available The interplay between the Apicomplexan parasite Toxoplasma gondii and its host has been largely studied. However, molecular changes at the metabolic level in the host central nervous system and pathogenesis-associated metabolites during brain infection are largely unexplored. We used a global metabolomics strategy to identify differentially regulated metabolites and affected metabolic pathways in BALB/c mice during infection with T. gondii Pru strain at 7, 14 and 21 days post-infection (DPI. The non-targeted Liquid Chromatography-Mass Spectrometry (LC-MS metabolomics analysis detected approximately 2,755 retention time-exact mass pairs, of which more than 60 had significantly differential profiles at different stages of infection. These include amino acids, organic acids, carbohydrates, fatty acids, and vitamins. The biological significance of these metabolites is discussed. Principal Component Analysis and Orthogonal Partial Least Square-Discriminant Analysis showed the metabolites' profile to change over time with the most significant changes occurring at 14 DPI. Correlated metabolic pathway imbalances were observed in carbohydrate metabolism, lipid metabolism, energetic metabolism and fatty acid oxidation. Eight metabolites correlated with the physical recovery from infection-caused illness were identified. These findings indicate that global metabolomics adopted in this study is a sensitive approach for detecting metabolic alterations in T. gondii-infected mice and generated a comparative metabolic profile of brain tissue distinguishing infected from non-infected host.

  11. Research on wide-bandgap intermediate band solar cells and development of experimental techniques for their characterization

    OpenAIRE

    Ramiro Gonzalez, Iñigo

    2015-01-01

    El trabajo que ha dado lugar a esta Tesis Doctoral se enmarca en la invesitagación en células solares de banda intermedia (IBSCs, por sus siglas en inglés). Se trata de un nuevo concepto de célula solar que ofrece la posibilidad de alcanzar altas eficiencias de conversión fotovoltaica. Hasta ahora, se han demostrado de manera experimental los fundamentos de operación de las IBSCs; sin embargo, esto tan sólo has sido posible en condicines de baja temperatura. El concepto de banda intermedia (I...

  12. Band-selective radiofrequency pulses

    Science.gov (United States)

    Geen, Helen; Freeman, Ray

    A theoretical treatment is given of the general problem of designing amplitude-modulated radiofrequency pulses that will excite a specified band of frequencies within a high-resolution NMR spectrum with uniform intensity and phase but with negligible excitation elsewhere. First a trial pulse envelope is defined in terms of a finite Fourier series and its frequency-domain profile calculated through the Bloch equations. The result is compared with the desired target profile to give a multidimensional error surface. The method of simulated annealing is then used to find the global minimum on this surface and the result refined by standard gradient-descent optimization. In this manner, a family of new shaped radio-frequency pulses, known as BURP ( band-selective, uniform response, pure-phase) pulses, has been created. These are of two classes—pulses that excite or invert z magnetization and those that act as general-rotation πr/2 or π pulses irrespective of the initial condition of the nuclear magnetization. It was found convenient to design the latter class as amplitude-modulated time-symmetric pulses. Tables of Fourier coefficients and pulse-shape ordinates are given for practical implementation of BURP pulses, together with the calculated frequency-domain responses and experimental verifications. Examples of the application of band-selective pulses in conventional and multidimensional spectroscopy are given. Pure-phase pulses of this type should also find applications in magnetic resonance imaging where refocusing schemes are undesirable.

  13. Transcriptional profiling of the bovine hepatic response to experimentally induced E. coli mastitis

    DEFF Research Database (Denmark)

    Jørgensen, Hanne Birgitte Hede; Buitenhuis, Bart; Røntved, Christine Maria;

    2012-01-01

    The mammalian liver works to keep the body in a state of homeostasis and plays an important role in systemic acute phase response to infections. In this study we investigated the bovine hepatic acute phase response at the gene transcription level in dairy cows with experimentally E. coli-induced ......The mammalian liver works to keep the body in a state of homeostasis and plays an important role in systemic acute phase response to infections. In this study we investigated the bovine hepatic acute phase response at the gene transcription level in dairy cows with experimentally E. coli...... were analyzed using the Bovine Genome Array and tested significant for 408 transcripts over the time series (adjusted p0.05; abs(fold-change)>2). After 2-D clustering, transcripts represented three distinct transcription profiles: 1) regulation of gene transcription and apoptosis, 2) responses to...

  14. Expression Profiling after Prolonged Experimental Febrile Seizures in Mice Suggests Structural Remodeling in the Hippocampus

    NARCIS (Netherlands)

    Jongbloets, Bart C; van Gassen, Koen L I; Kan, Anne A; Olde Engberink, Anneke H O; de Wit, Marina; Wolterink-Donselaar, Inge G; Groot Koerkamp, Marian J A; van Nieuwenhuizen, Onno; Holstege, Frank C P; de Graan, Pierre N E

    2015-01-01

    Febrile seizures are the most prevalent type of seizures among children up to 5 years of age (2-4% of Western-European children). Complex febrile seizures are associated with an increased risk to develop temporal lobe epilepsy. To investigate short- and long-term effects of experimental febrile seiz

  15. Experimental System for Simulating a Natural Soil Temperature Profile during Freeze-thaw Cycles

    Science.gov (United States)

    In order to better assess the effects of freeze-thaw cycles on soil physical properties, water and contaminant transport, and microbial activity, a simple experimental soil thermal cycling system was developed. The system consisted of an insulated bin containing four cylindrical PVC lysimeters encas...

  16. Experimental characterization of two-dimensional pencil beam scanning proton spot profiles.

    Science.gov (United States)

    Lin, Liyong; Ainsley, Christopher G; McDonough, James E

    2013-09-01

    Dose calculations of pencil beam scanning treatment plans rely on the accuracy of proton spot profiles; not only the primary component but also the broad tail components. Four films are placed at several locations in air and multiple depths in Solidwater® for six selected energies. The films used for the primary components are exposed to 50-200 MU to avoid saturation; the films used for the tail components are exposed to 800, 8000 and 80,000 MU. By applying a pair/magnification method and merging these data, dose kernels down to 10(-4) of the central spot dose can be generated. From these kernels one can calculate the dose-per-MU for different field sizes and shapes. Measurements agree within 1% of dose-kernel-based calculations for output versus field size comparisons. Asymmetric, comet-shaped profile tails have a bigger impact at superficial depths and low energies: the output difference between two orientations at the surface of a rectangular field of 40 mm×200 mm is about 2% at the isocentre at 100 MeV. Integration of these dose kernels from 0 to 40 mm radius shows that the charge deficit in the Bragg peak chamber varies <2% from entrance to the end of range for energies <180 MeV, but exceeds 5% at 225 MeV. PMID:23948730

  17. The field-dependent shock profiles of a magnetorhelogical damper due to high impact: an experimental investigation

    International Nuclear Information System (INIS)

    This work proposes a new damper featuring magnetorheological fluid (MR damper) and presents its field-dependent damping forces due to high impact. To achieve this goal, a large MR damper, which can produce a damping force of 100 kN at 6 A, is designed and manufactured based on the analysis of the magnetic flux intensity of the damper. After identifying the field-dependent damping force levels of the manufactured MR damper, a hydraulic horizontal shock tester is established. This shock testing system consists of a velocity generator, impact mass, shock programmer, and test mass. The MR damper is installed at the end of the wall in the shock tester and tested under four different experimental conditions. The shock profile characteristics of the MR damper due to different impact velocities are investigated at various input current levels. In addition, the inner pressure of the MR damper during impact, which depends on the input’s current level, is evaluated at two positions that can represent the pressure drop that generates the damping force of the MR damper. It is demonstrated from this impact testing that the shock profiles can be changed by the magnitude of the input current applied to the MR damper. It directly indicates that a desired shock profile can be achieved by installing the MR damper associated with appropriate control logics to adjust the magnitude of the input current. (paper)

  18. Time-resolved beam-profile measurements on the Experimental Test Accelerator (ETA)

    International Nuclear Information System (INIS)

    Examples are given of time-resolved beam profiles measured on ETA using several techniques. One method uses a Faraday cup that is remotely movable in two-transverse dimensions (x, y). In another method a small diameter wire or pellet target is moved across the beam and the bremsstrahlung x-ray intensity is plotted. Data for these methods are recorded using a Tektronix 7912 digitizer at 16 equally spaced times during 50 ns. Three other methods use a time gated (4 ns) microchannel plate television camera to record a two-dimensional image of the beam intensity on a single pulse. The light sources used for imaging are: Cherenkov light from a Kapton foil, prompt visible light from a titanium foil and radiated light from gas molecules excited by the beam. We are also testing an x-ray pinhole camera using K/sub α/ x-rays from tungsten

  19. AN EXPERIMENTAL INVESTIGATIONS INTO THE SPIKE PROFILE OBTAINED DURING ELECTROCHEMICAL HOLE DRILLING OF BLIND HOLES

    OpenAIRE

    P. V. Jadhav; D. S. Bilgi; A. S..Harel

    2011-01-01

    The Electrochemical Machining (ECM) has in recent times emerged as an important advanced machining process. The improvement in machining accuracy of electrochemical machining (ECM) continues to be a major challenge for user industries. This study focuses on the development of a precision ECM Process which uses with the traditional ECM. The feasibility of the proposed process has been experimentally verified.Attempts are being made to investigate optimum process parameters such as tool hole di...

  20. Velocity profiles and plug zones in a free surface viscoplastic flow : experimental study and comparison to shallow flow models

    Science.gov (United States)

    Freydier, Perrine; Chambon, Guillaume; Naaim, Mohamed

    2016-04-01

    Rheological studies concerning natural muddy debris flows have shown that these materials can be modelled as non-Newtonian viscoplastic fluids. These complex flows are generally represented using models based on a depth-integrated approach (Shallow Water) that take into account closure terms depending on the shape of the velocity profile. But to date, there is poor knowledge about the shape of velocity profiles and the position of the interface between sheared and unsheared regions (plug) in these flows, especially in the vicinity of the front. In this research, the internal dynamics of a free-surface viscoplastic flow down an inclined channel is investigated and compared to the predictions of a Shallow Water model based on the lubrication approximation. Experiments are conducted in an inclined channel whose bottom is constituted by an upward-moving conveyor belt with controlled velocity, which allows generating and observing gravity-driven stationary surges in the laboratory frame. Carbopol microgel has been used as a homogeneous and transparent viscoplastic fluid. High-resolution measurements of velocity field is performed through optical velocimetry techniques both in the uniform zone and within the front zone where flow thickness is variable and where recirculation takes place. Specific analyses have been developed to determine the position of the plug within the surge. Flow height is accessible through image processing and ultrasonic sensors. Sufficiently far from the front, experimental results are shown to be in good agreement with theoretical predictions regarding the velocity profiles and the flow height evolution. In the vicinity of the front, however, analysis of measured velocity profiles shows an evolution of the plug different from that predicted by lubrication approximation. Accordingly, the free surface shape also deviates from the predictions of the classical Shallow Water model. These results highlight the necessity to take into account higher

  1. Surface sensing behavior and band edge properties of AgAlS2: Experimental observations in optical, chemical, and thermoreflectance spectroscopy

    Directory of Open Access Journals (Sweden)

    Ching-Hwa Ho

    2012-06-01

    Full Text Available Optical examination of a chaocogenide compound AgAlS2 which can spontaneously transfer to a AgAlO2 oxide has been investigated by thermoreflectance (TR spectroscopy herein. The single crystals of AgAlS2 were grown by chemical vapor transport (CVT method using ICl3 as a transport agent sealed in evacuated quartz tubes. The as-grown AgAlS2 crystals essentially possess a transparent and white color in vacuum. The crystal surface of AgAlS2 becomes darkened and brownish when putting AgAlS2 into atmosphere for reacting with water vapor or hydrogen gas. Undergoing the chemical reaction process, oxygen deficient AgAlO2-2x with brownish and reddish-like color on surface of AgAlS2 forms. The transition energy of deficient AgAlO2-2x was evaluated by TR experiment. The value was determined to be ∼2.452 eV at 300 K. If the sample is kept dry and moved away from moisture, AgAlS2 crystal can stop forming more deficient AgAlO2-2x surface oxides. The experimental TR spectra for the surface-reacted sample show clearly two transition features at EW=2.452 eV for deficient AgAlO2-2x and EU=3.186 eV for AgAlS2, respectively. The EU transition belongs to direct band-edge exciton of AgAlS2. Alternatively, for surface-oxidation process of AgAlS2 lasting for a long time, a AgAlO2 crystal with yellowish color will eventually form. The TR measurements show mainly a ground-state band edge exciton of E OX 1 detected for AgAlO2. The energy was determined to be E OX 1=2.792 eV at 300 K. The valence-band electronic structure of AgAlS2 has been detailed characterized using polarized-thermoreflectance (PTR measurements in the temperature range between 30 and 340 K. Physical chemistry behaviors of AgAlS2 and AgAlO2 have been comprehensively studied via detailed analyses of PTR and TR spectra. Based on the experimental analyses, optical and chemical behaviors of the AgAlS2 crystals under atmosphere are realized. A possible optical-detecting scheme for using AgAlS2 as a humidity

  2. Experimental investigation of uranium-series isotope mobility in a basaltic weathering profile

    Science.gov (United States)

    Dosseto, Anthony; Menozzi, Davide; Kinsley, Leslie

    2015-04-01

    The measurement of uranium (U)-series isotopes in regolith can be used to determine the formation rate of weathering profiles. This approach aims at following how the U-series isotope composition of primary minerals (i.e. those derived from the parent material) vary during the development of the weathering profile. Nevertheless, regolith samples are a complex mixture of primary minerals, secondary minerals that are the residue of primary mineral weathering, secondary minerals that precipitate from pore water, minerals derived from atmospheric deposition and organic matter. In this study, firstly we aim at isolating primary minerals and the secondary minerals derived from them, by evaluating a sequential extraction procedure designed to eliminate carbonates, Fe-Mn oxides and organic matter. Secondly, we investigate the behaviour of U-series isotopes during primary mineral dissolution by applying a mild HF/HCl etching solution to the residues of the sequential extraction. These experiments were performed on bedrock, saprolite and soil derived from a basaltic weathering profile in south-eastern Australia. Results show that up to 50% of U is removed during sequential extraction, suggesting that (i) there is a large pool of labile U in the bedrock and (ii) secondary phases and organic matter account for a large fraction of the U budget in bulk saprolite and soil. Sequential extraction has little impact on the (234U/238U) activity ratio of bedrock and saprolite, whilst it shows a decrease in soil. This suggests that the pool of U removed from bedrock and saprolite has a (234U/238U) similar to that of primary minerals; but in the soil, the U removed (mostly from organic matter) is enriched in 234U. This is expected as organic matter uptakes U from pore solutions, which are generally enriched in 234U. During HF/HCl etching, the (234U/238U) of bedrock and saprolite is greater than 1. Sheng and Kuroda [1] previously proposed that (234U/238U) >1 in rocks could be explained by

  3. Experimental study of neuropharmacological profile of Euphorbia pulcherrima in mice and rats

    Directory of Open Access Journals (Sweden)

    Kundan Kr Singh

    2012-01-01

    Full Text Available Context: Euphorbia pulcherrima (EP belongs to the family: Euphorbiaceae and Genus: Euphorbia. Many species of Euphorbia have been reported as having beneficial properties like anticonvulsive effect, central analgesic properties, antipyretic action, central depressant action and strong sedative effect. However, little study has been done and published on EP. Aims: To observe and evaluate various neuropharmacological effects like antinociceptive effect, anticonvulsant effect, motor in-coordination, pentobarbital induced sleeping time and behavioral responses of EP in mice and rats. Setting and Design: Quantitative experimental study in mice and rats by various experimental models. Materials and Methods: Different experimental models were used to assess the antinociceptive effect (hotplate, tail flick and acetic acid induced writhing test, anticonvulsant effect (Maximal Electroshock Seizure test [MES] and Pentylenetetrazole induced seizures [PTZ], motor in-coordination effect (Rota rod test, pentobarbital induced sleeping time and behavioral responses of EP in mice and rats after oral administration of EP crude dried extracts in three different doses (250, 500 and 1000 mg/kg. Statistical Analysis Used: The significance of difference with respect to control was evaluated using the Mann-Whitney U test. A probability (P-value level less than 0.05 was considered as significant. Results: In MES test model, duration of tonic hind limb extension in mice treated with EP was significantly less as compared to vehicle treated group. EP was most effective in a dose of 1000 mg/kg. There was also significant increase in the latency and decrease in the incidence of convulsions with the use of EP in three different doses in PTZ induced seizure model. Conclusions: This study showed EP (crude dried extracts to possess anticonvulsant properties but no effect on motor co-ordination and anxiety.

  4. Universal limiting shape of worn profile under multiple-mode fretting conditions: theory and experimental evidence

    Science.gov (United States)

    Dmitriev, Andrey I.; Voll, Lars B.; Psakhie, Sergey G.; Popov, Valentin L.

    2016-03-01

    We consider multiple-mode fretting wear in a frictional contact of elastic bodies subjected to a small-amplitude oscillation, which may include in-plane and out-of-plane translation, torsion and tilting (“periodic rolling”). While the detailed kinetics of wear depends on the particular loading history and wear mechanism, the final worn shape, under some additional conditions, occurs to be universal for all types and loading and wear mechanisms. This universal form is determined solely by the radius of the permanent stick region and the maximum indentation depth during the loading cycle. We provide experimental evidence for the correctness of the theoretically predicted limiting shape. The existence of the universal limiting shape can be used for designing joints which are resistant to fretting wear.

  5. Impact of obesity on the expression profile of natriuretic peptide system in a rat experimental model.

    Directory of Open Access Journals (Sweden)

    Manuela Cabiati

    Full Text Available Natriuretic peptides (NPs play an important role in obesity and aim of this study was to evaluate, in cardiac tissue of obese Zucker rats (O, n = 29 their transcriptomic profile compared to controls (CO, n = 24 by Real-Time PCR study; CNP protein expression was evaluated by immunostaining and immunometric tests. Myocardial histology was performed, confirming no alteration of organ structure. While ANP and BNP are cardiac peptides, CNP is mainly an endothelial hormone; thus its expression, as well as that of NPR-B and NPR-C, was also evaluated in kidney and lung of an animal subgroup (n = 20. In heart, lower BNP mRNA levels in O vs CO (p = 0.02 as well as ANP and CNP (p = ns, were detected. NPR-B/NPR-A mRNA was similar in O and CO, while NPR-C was numerically lower (p = ns in O than in CO. In kidney, CNP/NPR-B/NPR-C mRNA was similar in O and CO, while in lung CNP/NPR-C expression decreased and NPR-B increased (p = ns in O vs CO. Subdividing into fasting and hyperglycemic rats, the pattern of mRNA expression for each gene analyzed remained unchanged. The trend observed in heart, kidney and lung for CNP protein concentrations and immunohistochemistry reflected the mRNA expression. TNF-α and IL-6 mRNA were measured in each tissue and no significant genotype effect was detected in any tissue. The main NP variations were observed at the cardiac level, suggesting a reduced release by cardiac cells. The understanding of mechanisms involved in the modulation of the NP system in obesity could be a useful starting point for future clinical study devoted to identifying new obesity treatment strategies.

  6. Antioxidant status and hormonal profile reflected by experimental feeding of probiotics.

    Science.gov (United States)

    Ghoneim, Magdy A; Moselhy, Said S

    2016-04-01

    Excessive production of free radicals can result in tissue damage, which mainly involves generation of hydroxyl radical and other oxidants. Such free radical-induced cell damage appears to play a major role in the pathogenesis of many diseases. Probiotics have been used therapeutically to modulate immunity, improve digestive processes, lower cholesterol, treat rheumatoid arthritis, and prevent cancer. The proposed research was designed to evaluate the changes in oxidative and antioxidative profile in addition to metabolic-related hormones of living animal model, which may generally affect the health status. Two groups of rabbits (10 animals each) were allocated in hygienic cages of controlled animal house. Control group received standard diet, and the other group received the same diet containing one probiotic for 30 days. Lactate dehydrogenase (LDH) activity in leukocytes, blood glucose, reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were estimated in different tissues. Malondialdehyde (MDA) and total proteins were also determined in different tissues. Certain hormones related to metabolism and growth were also evaluated. Leukocytic LDH activity was significantly increased along with nonsignificant increase of blood glucose in probiotics-fed animals. Results showed significant decreases in the levels of triiodothyronine and thyroid-stimulating hormone but showed significant elevations in thyroxine, insulin, growth hormone, and testosterone levels in animals fed with probiotics. Total proteins content was highly significantly elevated in liver, kidneys, and muscles of probiotic-administered animals. Microsomal GSH level was significantly decreased only in skeletal muscles of probiotic-treated animals. MDA was significantly lowered in animal tissues fed with probiotics. GSH-Px activity was elevated in hepatic and muscular microsomes of probiotic-supplemented animals while it was nonsignificantly increased in renal

  7. Experimental study on large flow rate monitoring downstream of double elbows using an ultrasonic velocity profile method

    International Nuclear Information System (INIS)

    This paper describes simple flow rate monitoring using the Ultrasonic Velocity Profile method (UVP), for disturbed flow just after double elbows and large pipes with high Reynolds numbers. This method utilizes the linearity between the flow rate and the velocity at the pipe center under the following flow conditions. The Reynolds number is from 4.1×106 to 5.1×106, the dihedral angle of double elbows is 30° and the distance between double elbows is six diameters. The measuring position is set at two diameters distance downstream of the second elbow. The Computational Fluid Dynamics (CFD) simulations and experimental results indicate that it can monitor flow rate changes with an accuracy of less than 1% under these flow conditions. (author)

  8. Computational modeling and experimental studies of the dynamic performance of ultrasonic horn profiles used in plastic welding.

    Science.gov (United States)

    Roopa Rani, M; Rudramoorthy, R

    2013-03-01

    Ultrasonic horns are tuned components designed to vibrate in a longitudinal mode at ultrasonic frequencies. Reliable performance of such horns is normally decided by the uniformity of vibration amplitude at the working surface and the stress developed during loading condition. The horn design engineer must pay particular attention to designing a tool that will produce the desired amplitude without fracturing. The present work discusses horn configurations which satisfy these criteria and investigates the design requirements of horns in ultrasonic system. Different horn profiles for ultrasonic welding of thermoplastics have been characterized in terms of displacement amplitude and von-Mises stresses using modal and harmonic analysis. To validate the simulated results, five different horns are fabricated from Aluminum, tested and tuned to the operating frequency. Standard ABS plastic parts are welded using these horns. Temperature developed during the welding of ABS test parts using different horns is recorded using sensors and National Instruments (NIs) data acquisition system. The recorded values are compared with the predicted values. Experimental results show that welding using a Bezier horn has a high interface temperature and the welded joints had higher strength as compared to the other horn profiles. PMID:23259979

  9. MediPlEx - a tool to combine in silico & experimental gene expression profiles of the model legume Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Stutz Leonhard J

    2010-10-01

    Full Text Available Abstract Background Expressed Sequence Tags (ESTs are in general used to gain a first insight into gene activities from a species of interest. Subsequently, and typically based on a combination of EST and genome sequences, microarray-based expression analyses are performed for a variety of conditions. In some cases, a multitude of EST and microarray experiments are conducted for one species, covering different tissues, cell states, and cell types. Under these circumstances, the challenge arises to combine results derived from the different expression profiling strategies, with the goal to uncover novel information on the basis of the integrated datasets. Findings Using our new analysis tool, MediPlEx (MEDIcago truncatula multiPLe EXpression analysis, expression data from EST experiments, oligonucleotide microarrays and Affymetrix GeneChips® can be combined and analyzed, leading to a novel approach to integrated transcriptome analysis. We have validated our tool via the identification of a set of well-characterized AM-specific and AM-induced marker genes, identified by MediPlEx on the basis of in silico and experimental gene expression profiles from roots colonized with AM fungi. Conclusions MediPlEx offers an integrated analysis pipeline for different sets of expression data generated for the model legume Medicago truncatula. As expected, in silico and experimental gene expression data that cover the same biological condition correlate well. The collection of differentially expressed genes identified via MediPlEx provides a starting point for functional studies in plant mutants. MediPlEx can freely be used at http://www.cebitec.uni-bielefeld.de/mediplex.

  10. An experimental and theoretical study of the A˜ 2A″Π -X˜ 2A' band system of the jet-cooled HBBr/DBBr free radical

    Science.gov (United States)

    Gharaibeh, Mohammed; Clouthier, Dennis J.; Tarroni, Riccardo

    2016-06-01

    The electronic spectra of the HBBr and DBBr free radicals have been studied in depth. These species were prepared in a pulsed electric discharge jet using a precursor mixture of BBr3 vapor and H2 or D2 in high pressure argon. Transitions to the electronic excited state of the jet-cooled radicals were probed with laser-induced fluorescence and the ground state energy levels were measured from the single vibronic level emission spectra. HBBr has an extensive band system in the red which involves a linear-bent transition between the two Renner-Teller components of what would be a 2Π state at linearity. We have used high level ab initio theory to calculate potential energy surfaces for the bent 2A' ground state and the linear A˜ 2A″Π excited state and we have determined the ro-vibronic energy levels variationally, including spin orbit effects. The correspondence between the computed and experimentally observed transition frequencies, upper state level symmetries, and H and B isotope shifts was used to make reliable assignments. We have shown that the ground state barriers to linearity, which range from 10 000 cm-1 in HBF to 2700 cm-1 in BH2, are inversely related to the energy of the first excited 2Σ (2A') electronic state. This suggests that a vibronic coupling mechanism is responsible for the nonlinear equilibrium geometries of the ground states of the HBX free radicals.

  11. Experimental evidence of the photonic band gap in hybrid one-dimensional photonic crystal based on a mixture of (HMDSO, O2)

    Science.gov (United States)

    Amri, R.; Sahel, S.; Manaa, C.; Bouaziz, L.; Gamra, D.; Lejeune, M.; Clin, M.; Zellama, K.; Bouchriha, H.

    2016-08-01

    Hybrid One-dimensional photonic crystal coated from a mixture of an organic compound (HMDSO) and oxygen (O2) is elaborated by PECVD technique. The originality of the method consists in obtaining layers of different permittivity with the same gas mixture, but with different flow. The change in flow is optimized to obtain organic/inorganic layers of good quality with high and low refractive index of 2.1 and 1.4 corresponding respectively to HMDSO and SiO2 materials as assigned by IR measurement. Evidence of the photonic band gap is obtained by measuring the transmissions and reflections spectra which show that it appears only after 13 periods with a width of 325 nm corresponding to energy 3.8 eV. We have also introduced a defect in this photonic structure by changing the thickness of central layer, and observed the presence of a frequency mode corresponding to this defect. Our results are interpreted by using a theoretical model based on transfer matrix wich well reproduced the experimental data.

  12. Microarray-based gene expression profiling of peripheral blood mononuclear cells in dairy cows with experimental hypocalcemia and milk fever.

    Science.gov (United States)

    Sasaki, K; Yamagishi, N; Kizaki, K; Sasaki, K; Devkota, B; Hashizume, K

    2014-01-01

    Although a molecular diagnostic assay using clinically accessible tissue, such as blood, would facilitate evaluation of disease conditions in humans and animals, little information exists on microarray-based gene expression profiling of circulating leukocytes from clinically hypocalcemic cows. Therefore, peripheral blood mononuclear cells from dairy cows with experimentally induced hypocalcemia or spontaneous milk fever were subjected to oligo-microarray analysis to identify specific biomarker genes. In experimental hypocalcemia induced by a 4-h infusion of 10% disodium EDTA (n=4), 32 genes were significantly up- or downregulated compared with control treatment (4-h infusion of 11% calcium EDTA; n=4). In cows with milk fever (n=8), 98 genes were expressed differentially (either up- or downregulated) compared with healthy parturient cows (n=5). From these data, the following 5 genes were selected as being strongly related to both experimental hypocalcemia and milk fever: protein kinase (cAMP-dependent, catalytic) inhibitor β (PKIB); DNA-damage-inducible transcript 4 (DDIT4); period homolog 1 (PER1); NUAK family, SNF1-like kinase, 1 (NUAK1); and expressed sequence tag (BI537947). Another gene (neuroendocrine secretory protein 55, NESP55) was also determined to be specific for milk fever, independently of hypocalcemia. The mRNA expression of these 6 genes in milk fever cases was verified by quantitative real-time reverse-transcription PCR and was significantly different compared with their expression in healthy parturient cows. In the present study, the selected genes appeared to be candidate biomarkers of milk fever because the continuous interactions between blood cells and the entire body suggest that subtle intracellular changes occur in association with disease. However, before any genomic biomarkers are incorporated into clinical evaluation of the disease, the effect of hypocalcemia on the mRNA expression of these genes in the tissues that regulate calcium

  13. Profiling of impurities in p-methoxymethamphetamine (PMMA) by means of SPE/TLC method. Examination of the influence of experimental conditions according to 2(4) factorial.

    Science.gov (United States)

    Kochana, J; Wilamowski, J; Parczewski, A

    2003-07-01

    In the present paper profiling of impurities in p-methoxymethamphetamine (PMMA) by means of SPE/TLC is reported. PMMA was synthesised by Leuckart procedure. The influence of experimental conditions on the profile quality was investigated. The experiments were carried out according to a 2(4) factorial. The proposed characteristics of the profile quality (optimisation criterions) are based on a matrix presentation of TLC patterns. They take into account, simultaneously, the number of spots revealed, differences between R(f) values and intensity of fluorescence. PMID:12850419

  14. Electron density profiles in the quiet lower ionosphere based on the results of modeling and experimental data

    Directory of Open Access Journals (Sweden)

    V. Barabash

    2012-09-01

    Full Text Available The theoretical PGI (Polar Geophysical Institute model for the quiet lower ionosphere has been applied for computing the ionization rate and electron density profiles in the summer and winter D-region at solar zenith angles less than 80° and larger than 99° under steady state conditions. In order to minimize possible errors in estimation of ionization rates provided by solar electromagnetic radiation and to obtain the most exact values of electron density, each wavelength range of the solar spectrum has been divided into several intervals and the relations between the solar radiation intensity at these wavelengths and the solar activity index F10.7 have been incorporated into the model. Influence of minor neutral species (NO, H2O, O, O3 concentrations on the electron number density at different altitudes of the sunlit quiet D-region has been examined. The results demonstrate that at altitudes above 70 km, the modeled electron density is most sensitive to variations of nitric oxide concentration. Changes of water vapor concentration in the whole altitude range of the mesosphere influence the electron density only in the narrow height interval 73–85 km. The effect of the change of atomic oxygen and ozone concentration is the least significant and takes place only below 70 km.

    Model responses to changes of the solar zenith angle, solar activity (low–high and season (summer–winter have been considered. Modeled electron density profiles have been evaluated by comparison with experimental profiles available from the rocket measurements for the same conditions. It is demonstrated that the theoretical model for the quiet lower ionosphere is quite effective in describing variations in ionization rate, electron number density and effective recombination coefficient as functions of solar zenith angle, solar activity and season. The model may be used for solving inverse tasks, in particular, for

  15. [Determination of relative error of pressure-broadening linewidth for the experimentally indistinguishable overlapped spectral lines with Voigt profile].

    Science.gov (United States)

    Lin, Jie-Li; Huang, Yi-Qing; Lu, Hong

    2005-01-01

    The simulation and fitting of the overlapped spectral lines with Voigt profile were presented in this paper. The relative errors epsilon of the fitted pressure-broadening linewidth when taking the overlapped spectral line as one spectrum were discussed in detail. The relationship between such error and the two spectral lines center distance deltav0, and theoretical pressure-broadening linewidth deltav(L)0 were analyzed. Epsilon is found to be very large and the relationship between epsilon and deltav0, deltav(L)0 is very complicated when the value of pressure-broadening linewidth is considerably less than that of Dopplerian one deltavD. When deltav(L)0 is comparative to deltaVD the relationship between epsilon and deltav0 is close to the smooth two-order polynomial curve. However, the slop of this curve is negative while deltav(L)0 is smaller than deltavD and is positive when larger. Generally, epsilon decreases with the increase of proportion of deltav(l)0 to the whole spectral linewidth. All the above conclusion and corresponding data are the significant reference to determine the precise pressure-broadening coefficient from the experimentally indistinguishable overlapped spectrum, as well as to correct the fitted pressure-broadening linewidth. PMID:15852837

  16. Analysis of the hydraulic effects associated to the location of an inflatable rubber weir over a spillway profile through experimental and numerical (CFD model

    Directory of Open Access Journals (Sweden)

    Sarai Díaz García

    2015-04-01

    Full Text Available The ease of rubber weirs to adapt themselves to different flow conditions makes them interesting for placement over spillway profiles, allowing to increase the stored volume in ordinary operation without compromising the dam’s response in case of flooding. The objective of this study is to analyze the effect of locating an inflatable weir over a spillway profile in what regards its hydraulic response. With this purpose, an experimental and a numerical CFD model of a WES original spillway profile are developed, to then include an EPDM weir whose effect is analyzed for different inflation levels. Numerical and experimental results are close and highlight significant variations in the pressure distribution along the spillway, with aeration playing a significant role. This study concludes that the placement of this particular inflatable weir has an overall positive result if conveniently undertaken, but additional studies with different geometries are required to delve in the topic.

  17. Cytokine and C-reactive protein profiles induced by porcine circovirus type 2 experimental infection in 3-week-old piglets

    DEFF Research Database (Denmark)

    Stevenson, L.S.; McCullough, K.; Vincent, I.; Gilpin, D.F.; Summerfield, A.; Nielsen, Jens; McNeilly, F.; Adair, B.M.; Allan, G.M.

    2006-01-01

    The purpose of this study was to determine serum profiles of cytokines at a protein level and C-reactive protein (CRP) during the development of postweaning multisystemic wasting syndrome (PMWS) in experimentally inoculated pigs. Levels of serum IFN-alpha, IL-6, IL-10, and CRP were examined for a...

  18. Design and implementation of low profile antenna for dual-band applications using rotated e-shaped conductor-backed plane.

    Science.gov (United States)

    Jalali, Mahdi; Sedghi, Tohid; Shafei, Shahin

    2014-01-01

    A novel configuration of a printed monopole antenna with a very compact size for satisfying WLAN operations at the 5.2/5.8 GHz and also for X-band operations at the 10 GHz has been proposed. The antenna includes a simple square-shaped patch as the radiator, the rotated U-shaped conductor back plane element with embedded strip on it, and the partial rectangular ground surface. By using the rotated U-shaped conductor-backed plane with proper values, good impedance matching and improvement in bandwidth can be achieved, at the lower and upper bands. The impedance bandwidth for S11 antenna with good omnidirectional radiation characteristics, enough impedance bandwidth, and reasonable gains can be appropriate for various applications of the future developed technologies and handheld devices. PMID:24711732

  19. Statistical and Prediction modeling of the Ka Band Using Experimental Results from ACTS Propagation Terminals at 20.185 and 27.505 GHZ

    Science.gov (United States)

    Ogunwuyi, Oluwatosin O.

    2004-01-01

    With the increase in demand for wireless communication services, most of the operating frequency bands have become very congested. The increase of wireless costumers is only fractional contribution to this phenomenon. The demand for more services such as video streams and internet explorer which require a lot of band width has been a more significant contributor to the congestion in a communication system. One way to increase the amount of information or data per unit of time transmitted with in a wireless communication system is to use a higher radio frequency. However in spite the advantage available in the using higher frequency bands such as, the Ka-band, higher frequencies also implies short wavelengths. And shorter wavelengths are more susceptible to rain attenuation. Until the Advanced Communication Technology Satellite (ACTS) was launched, the Ka- band frequency was virtually unused - the majority of communication satellites operated in lower frequency bands called the C- and Ku- bands. Ka-band is desirable because its higher frequency allows wide bandwidth applications, smaller spacecraft and ground terminal components, and stronger signal strength. Since the Ka-band is a high frequency band, the millimeter wavelengths of the signals are easily degraded by rain. This problem known as rain fade or rain attenuation The Advanced Communication Technology Satellite (ACTS) propagation experiment has collected 5 years of Radio Frequency (RF) attenuation data from December 1993 to November 1997. The objective of my summer work is to help develop the statistics and prediction techniques that will help to better characterize the Ka Frequency band. The statistical analysis consists of seasonal and cumulative five-year attenuation statistics for the 20.2 and 27.5 GHz. The cumulative five-year results give the link outage that occurs for a given link margin. The experiment has seven ground station terminals that can be attributed to a unique rain zone climate. The

  20. First-principles calculations of bismuth induced changes in the band structure of dilute Ga-V-Bi and In-V-Bi alloys: chemical trends versus experimental data

    Science.gov (United States)

    Polak, M. P.; Scharoch, P.; Kudrawiec, R.

    2015-09-01

    Bi-induced changes in the band structure of Ga-V-Bi and In-V-Bi alloys are calculated within the density functional theory (DFT) for alloys with Bi ≤3.7% and the observed chemical trends are discussed in the context of the virtual crystal approximation (VCA) and the valence band anticrossing (VBAC) model. It is clearly shown that the incorporation of Bi atoms into III-V host modifies both the conduction band (CB) and the valence band (VB). The obtained shifts of bands in GaP1-xBix, GaAs1-xBix, GaSb1-xBix, InP1-xBix, InAs1-xBix, and InSb1-xBix are respectively, 15, -29, -16, -27, -15, and -10 meV/%Bi for CB, 82, 62, 16, 79, 45, and 16 meV/%Bi for VB, and -17, -3, -2, -8, -6, and 14 meV/%Bi for spin-orbit split off band. The Bi-induced reduction of the band gap is very consistent with the available experimental data. The chemical trends observed in our calculations as well as in experimental data are very clear: in a sequence of alloys from III-P-Bi to III-Sb-Bi the Bi-induced changes in the band structure weaken. For dilute GaSb1-xBix and InSb1-xBix alloys the band structure modification, in the first approximation, can be described within the VCA, while for Ga-V-Bi and In-V-Bi alloys with V = As or P another phenomenological approach is needed to predict the Bi-induced changes in their band structure. We have found that a combination of the VCA with the VBAC model, which is widely applied for highly mismatched alloys, is suitable for this purpose. The chemical trends for III-V-Bi alloys observed in our DFT calculations are also exhibited by the coupling parameter {C}BiM, which describes the magnitude of interaction between Bi-induced levels and VB states in the VBAC model. This coupling parameter monotonously decreases along the sequence of alloys from III-P-Bi to III-Sb-Bi.

  1. Single Band Helical Antenna in Axial Mode

    Directory of Open Access Journals (Sweden)

    Parminder Singh

    2012-11-01

    Full Text Available Helical antennas have been widely used in a various useful applications, due to their low weight and low profile conformability, easy and cheap realization.Radiation properties of this antenna are examined both theoretically and experimentally. In this paper, an attempt has been made to investigate new helical antenna structure for Applications. CST MWS Software is used for the simulation and design calculations of the helical antennas. The axial ratio, return loss, VSWR, Directivity, gain, radiation pattern is evaluated. Using CST MWS simulation software proposed antenna is designed/simulated and optimized. The antenna exhibits a single band from 0 GHz to 3 GHz for GPS and several satellite applications

  2. Gastric Banding

    Science.gov (United States)

    ... gastric banding before deciding to have the procedure. Advertisements for a device or procedure may not include ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  3. High-resolution, H band Spectroscopy of Be Stars with SDSS-III/APOGEE: I. New Be Stars, Line Identifications, and Line Profiles

    CERN Document Server

    Chojnowski, S Drew; Wisniewski, John P; Majewski, Steven R; Hall, Matthew; Shetrone, Matthew; Beaton, Rachael; Burton, Adam; Damke, Guillermo; Eikenberry, Steve; Hasselquist, Sten; Holtzman, Jon A; Meszaros, Szabolcs; Nidever, David; Schneider, Donald P; Wilson, John; Zasowski, Gail; Bizyaev, Dmitry; Brewington, Howard; Brinkmann, J; Ebelke, Garrett; Frinchaboy, Peter M; Kinemuchi, Karen; Malanushenko, Elena; Malanushenko, Viktor; Marchante, Moses; Oravetz, Daniel; Pan, Kaike; Simmons, Audrey

    2014-01-01

    APOGEE has amassed the largest ever collection of multi-epoch, high-resolution (R~22,500), H-band spectra for B-type emission line (Be) stars. The 128/238 APOGEE Be stars for which emission had never previously been reported serve to increase the total number of known Be stars by ~6%. We focus on identification of the H-band lines and analysis of the emission peak velocity separations (v_p) and emission peak intensity ratios (V/R) of the usually double-peaked H I and non-hydrogen emission lines. H I Br11 emission is found to preferentially form in the circumstellar disks at an average distance of ~2.2 stellar radii. Increasing v_p toward the weaker Br12--Br20 lines suggests these lines are formed interior to Br11. By contrast, the observed IR Fe II emission lines present evidence of having significantly larger formation radii; distinctive phase lags between IR Fe II and H I Brackett emission lines further supports that these species arise from different radii in Be disks. Several emission lines have been iden...

  4. CONTROL OF LASER RADIATION PARAMETERS: Experimental investigation of the spatial structure of the beam profile of a laser with a Sagnac interferometer

    Science.gov (United States)

    Grabovskii, V. V.; Prokhorenko, V. I.; Yatskiv, D. Ya

    1996-04-01

    An experimental investigation was made of the spatial structure of the output beam profile of an Nd3+:YAG laser with a cavity based on a Sagnac interferometer. In a wide range of pulse repetition frequencies, the output beam profile could be described by a Gaussian curve with a confidence probability of at least 99%. This corresponded to the emission of the TEM00 mode from a stable cavity. The diameter of the radiation spot was inversely proportional to the shift of a thermo-optical lens from the centre of the Sagnac interferometer.

  5. Experimental Profiling of a Non-truncated Focused Gaussian Beam and Fine-tuning of the Quadratic Phase in the Fresnel Gaussian Shape Invariant

    Energy Technology Data Exchange (ETDEWEB)

    S., Juan Manuel Franco [Center of Investigation (CIO) (Mexico); Cywiak, Moises [Center of Investigation (CIO) (Mexico); Cywiak, David [National Metrology Center (Mexico); Mourad, Idir [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-06-24

    A homodyne profiler is used for recording the intensity distribution of focused non-truncated Gaussian beams. The spatial distributions are obtained at planes in the vicinity of the back-focal plane of a focusing lens placed at different distances from a He–Ne laser beam with a Gaussian intensity profile. Comparisons of the experimental data with those obtained from the analytical equations for an ideal focusing lens allow us to propose formulae to fine-tune the quadratic term in the Fresnel Gaussian shape invariant at each interface of the propagated field. Furthermore, we give analytical expressions to calculate adequately the propagation of the field through an optical system.

  6. Experimental profiling of a non-truncated focused Gaussian beam and fine-tuning of the quadratic phase in the Fresnel Gaussian shape invariant

    Science.gov (United States)

    Franco S, Juan Manuel; Cywiak, Moisés; Cywiak, David; Mourad, Idir

    2015-11-01

    An especially dedicated homodyne profiler is used for recording the intensity distribution of focused non-truncated Gaussian beams. The spatial distributions are obtained at planes in the vicinity of the back-focal plane of a focusing lens placed at different distances from a He-Ne laser beam with a Gaussian intensity profile. Comparisons of the experimental data with those obtained from the analytical equations for an ideal focusing lens allow us to propose formulae to fine-tune the quadratic term in the Fresnel Gaussian shape invariant at each interface of the propagated field. We give analytical expressions to calculate adequately the propagation of the field through an optical system.

  7. 2-GHz band CW and W-CDMA modulated radiofrequency fields have no significant effect on cell proliferation and gene expression profile in human cells.

    Science.gov (United States)

    Sekijima, Masaru; Takeda, Hiroshi; Yasunaga, Katsuaki; Sakuma, Noriko; Hirose, Hideki; Nojima, Toshio; Miyakoshi, Junji

    2010-01-01

    We investigated the mechanisms by which radiofrequency (RF) fields exert their activity, and the changes in both cell proliferation and the gene expression profile in the human cell lines, A172 (glioblastoma), H4 (neuroglioma), and IMR-90 (fibroblasts from normal fetal lung) following exposure to 2.1425 GHz continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) RF fields at three field levels. During the incubation phase, cells were exposed at the specific absorption rates (SARs) of 80, 250, or 800 mW/kg with both CW and W-CDMA RF fields for up to 96 h. Heat shock treatment was used as the positive control. No significant differences in cell growth or viability were observed between any test group exposed to W-CDMA or CW radiation and the sham-exposed negative controls. Using the Affymetrix Human Genome Array, only a very small (CDMA RF fields for up to 96 h did not act as an acute cytotoxicant in either cell proliferation or the gene expression profile. These results suggest that RF exposure up to the limit of whole-body average SAR levels as specified in the ICNIRP guidelines is unlikely to elicit a general stress response in the tested cell lines under these conditions. PMID:20215713

  8. Experimental investigation on plasma parameter profiles on a wafer level with reactor gap lengths in an inductively coupled plasma

    International Nuclear Information System (INIS)

    The gap length effect on plasma parameters is investigated in a planar type inductively coupled plasma at various conditions. The spatial profiles of ion densities and the electron temperatures on the wafer level are measured with a 2D probe array based on the floating harmonic method. At low pressures, the spatial profiles of the plasma parameters rarely changed by various gap lengths, which indicates that nonlocal kinetics are dominant at low pressures. However, at relatively high pressures, the spatial profiles of the plasma parameter changed dramatically. These plasma distribution profile characteristics should be considered for plasma reactor design and processing setup, and can be explained by the diffusion of charged particles and the local kinetics

  9. Combined experimental and statistical strategy for mass spectrometry based serum protein profiling for diagnosis of breast cancer

    DEFF Research Database (Denmark)

    Callesen, Anne Kjærgaard; Vach, Werner; Jørgensen, Per E; Cold, Søren; Tan, Qihua; Depont Christensen, René; Mogensen, Ole; Kruse, Torben; Madsen, Jonna Skov; Jensen, Ole Nørregaard

    2008-01-01

    Serum protein profiling by mass spectrometry is a promising method for early detection of cancer. We have implemented a combined strategy based on matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) and statistical data analysis for serum protein profiling and applied it in a...... of nine mass spectrometric protein profiles were obtained for each serum sample. A total of 533 common peaks were defined and represented a 'reference protein profile'. Among these 533 common peaks, we identified 72 peaks exhibiting statistically significant intensity differences ( p < 0.01) between...... cases and controls. A diagnostic rule based on these 72 mass values was constructed and exhibited a cross-validated sensitivity and specificity of approximately 85% for the detection of breast cancer. With this method, it was possible to distinguish early stage cancers from controls without major loss...

  10. Experimental Demonstration of Nonlinearity and Phase Noise Tolerant 16-QAM OFDM W-Band (75–110 GHz) Signal Over Fiber System

    DEFF Research Database (Denmark)

    Deng, Lei; Pang, Xiaodan; Tafur Monroy, Idelfonso; Tang, Ming; Shum, Ping; Liu, Deming

    2014-01-01

    We propose a nonlinearity and phase noise tolerant orthogonal frequency division multiplexing (OFDM) W-band signal over fiber system based on phase modulation and photonic heterodyne up-conversion techniques. By heterodyne mixing the phase-modulated optical OFDM signal with a free-running laser i...

  11. Accumulation profiles of PrPSc in hemal nodes of naturally and experimentally scrapie-infected sheep

    OpenAIRE

    Dassanayake, Rohana P; Truscott, Thomas C; Özyiğit, M Özgür; Zhuang, Dongyue; Schneider, David A; O’Rourke, Katherine I.

    2013-01-01

    Background In classical scrapie, the disease-associated abnormal isoform (PrPSc) of normal prion protein accumulates principally in the nervous system and lymphoid tissues of small ruminants. Lymph nodes traffic leukocytes via lymphatic and blood vasculatures but hemal nodes lack lymphatic vessels and thus traffic leukocytes only via the blood. Although PrPSc accumulation profiles are well-characterized in ovine lymphoid tissues, there is limited information on such profiles in hemal nodes. T...

  12. A study of high-temperature heat pipes with multiple heat sources and sinks. I - Experimental methodology and frozen startup profiles. II - Analysis of continuum transient and steady-state experimental data with numerical predictions

    Science.gov (United States)

    Faghri, A.; Cao, Y.; Buchko, M.

    1991-01-01

    Experimental profiles for heat pipe startup from the frozen state were obtained, using a high-temperature sodium/stainless steel pipe with multiple heat sources and sinks to investigate the startup behavior of the heat pipe for various heat loads and input locations, with both low and high heat rejection rates at the condensor. The experimental results of the performance characteristics for the continuum transient and steady-state operation of the heat pipe were analyzed, and the performance limits for operation with varying heat fluxes and location are determined.

  13. Hematological and biochemical profiles of rats submitted to experimental poisoning with Tityus serrulatus venom Perfis hematológicos de ratos submetidos ao envenenamento escorpiônico experimental por Tityus serrulatus

    OpenAIRE

    M.C.L. Pinto; M.M. Melo; M.E.R. Costa; C.R. Labarrere

    2010-01-01

    The hematological and biochemical profiles of newly weaned rats submitted to experimental poisoning with T. serrulatus venom were evaluated. Fifteen recently weaned male Wistar rats (mean weight 130g) were distributed into three equal groups (n = 5). Animals in the control group (group A) received a subcutaneous injection of 400μL of ultra-pure water, while those in the experimental groups received, by identical route, 400μL of a solution containing 100μg (group B) or 450μ...

  14. Profiling the local carrier concentration across a semiconductor quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Walrath, J. C.; Lin, Yen-Hsiang [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Huang, S. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Goldman, R. S., E-mail: rsgold@umich.edu [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2015-05-11

    We profile the local carrier concentration, n, across epitaxial InAs/GaAs quantum dots (QDs) consisting of 3D islands on top of a 2D alloy layer. We use scanning thermoelectric microscopy to measure a profile of the temperature gradient-induced voltage, which is converted to a profile of the local Seebeck coefficient, S. The S profile is then converted to a conduction band-edge profile and compared with Poisson-Schrodinger band-edge simulations. Our combined computational-experimental approach suggests a reduced carrier concentration in the QD center in comparison to that of the 2D alloy layer. The relative roles of free carrier trapping and/or dopant expulsion are discussed.

  15. Experimental three-dimensional beam profiling and modeling of a terahertz beam generated from a two-color air plasma

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Strikwerda, Andrew; Iwaszczuk, Krzysztof;

    2013-01-01

    shift in the focal region, and the transition from the donut profile to a central peak is consistent with propagation of a Bessel–Gauss beam, as shown by simulations based on a recent transient photocurrent model (You et al 2012 Phys. Rev. Lett. 109 183902). We combine our measurements to the first full...

  16. Physics and control of ELMing H-mode negative-central-shear advanced tokamak ITER scenario based on experimental profiles from DIII-D

    International Nuclear Information System (INIS)

    Key DIII-D advanced tokamak (AT) experimental and modelling results are applied to examine the physics and control issues for ITER to operate in a negative central shear (NCS) AT scenario. The effects of a finite edge pressure pedestal and current density are included based on the DIII-D experimental profiles. Ideal and resistive stability analyses demonstrate that feedback control of resistive wall modes by rotational drive or flux conserving intelligent coils is crucial for these AT configurations to operate at attractive βN values in the range 3.0-3.5. Vertical stability and halo current analyses show that reliable disruption mitigation is essential and mitigation control using an impurity gas can significantly reduce the local mechanical stress to an acceptable level. Core transport and turbulence analyses indicate that control of the rotational shear profile is essential to reduce the pedestal temperature required for high β. Consideration of edge stability and core transport suggests that a sufficiently wide pedestal is necessary for the projected fusion performance. Heat flux analyses indicate that, with core-only radiation enhancement, the outboard peak divertor heat load is near the design limit of 10 MW m-2. Detached operation may be necessary to reduce the heat flux to a more manageable level. Evaluation of the ITER pulse length using a local step response approach indicates that the 3000 s ITER long-pulse scenario is probably both necessary and sufficient for demonstration of local current profile control. (author)

  17. Measurements of power profile of the BN-600 commercial fast reactor by gamma-scanning and analytical studies of experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Izotov, V. V.; Kotchetkov, A. L.; Moiseev, A. V.; Semyonov, M. Y.; Seryogin, A. S.; Prishchepa, V. V.; Khomyakov, Y. S.; Tsyboulya, A. M. [State Scientific Center of the Russian Federation, Inst. for Physics and Power Engineering, 1 Bondarenko Square, Obninsk, Kaluga Region 249033 (Russian Federation); Dubrovsky, V. V.; Zheltyshev, V. A.; Ivanov, A. A.; Lyzhin, A. A.; Maltsev, V. V.; Mitrofanov, S. Y.; Roslyakov, V. F. [Branch of Rosenergoatom Concern, Beloyarsk NPP, Zarechny Sverdlovsk Region 624250 (Russian Federation); Belov, A. A.; Pryanitchnikov, A. V.; Seleznyov, E. F. [All-Russian Research Inst. on Operation of Nuclear Power Plants (VNIIAES), 25 Ferganskaya, Moscow 109507 (Russian Federation); Vasiliev, B. A.; Farakshin, M. P. [Experimental Design Bureau of Mechanical Engineering, 15 Burnakovsky Proezd, Nizhny Novgorod 603074 (Russian Federation)

    2006-07-01

    During 25 years of operation of BN-600 fast reactor at the Beloyarsk NPP, complex of analytical and experimental measurements has been developed for control of power rate distribution in the reactor core. Continuous control is performed by computational accompaniment based on three-dimensional multi-group analysis in hexagonal geometry in diffusion approximation. Periodical control is made by measuring of power rate profile in the standard fuel subassemblies of the BN-600 reactor by gamma scanning method on the stages of updating of the reactor core. By now, two cycles of such measurements have been performed when changing for the new reactor core design 01M2 providing 4-fold refueling mode and max fuel burn-up increased up to {approx}11.1% h.a. In the paper given are brief description of analytical and experimental methods of monitoring of power profile of the BN-600 reactor, results of their comparison and estimation of their precision based on the results of the above studies. It has been demonstrated that the use of 26-group diffusion approximation and GEFEST, JARFR and TRIGEX codes with ABBN-93 nuclear data gives adequate description of power rate distribution among the SAs of the BN-600 reactor core. Conservative estimation of calculation error is 5%. The main concern is evaluation of power profile of peripheral areas of the radial blanket and in-vessel storage, if achieved accuracy of 10-15% is insufficient. (authors)

  18. Kinks in experimental diffusion profiles of a dissolving semi-crystalline polymer explained by a concentration-dependent diffusion coefficient.

    Science.gov (United States)

    Hermes, Helen E; Sitta, Christoph E; Schillinger, Burkhard; Löwen, Hartmut; Egelhaaf, Stefan U

    2015-06-28

    The dissolution of polyethylene oxide (PEO) tablets in water has been followed in situ by neutron radiography. When in contact with water, the crystalline phase of semi-crystalline PEO melts once a certain water content is attained. Polymer concentration profiles obtained from the neutron transmission images exhibited a pronounced kink which corresponds to a sharp front in the images and which is related to the melting transition. Sharp diffusion fronts and phase transitions are often linked to non-Fickian behaviour. However, by considering the time evolution of the complete concentration profiles in detail it is shown that the dissolution process can be explained using Fickian diffusion equations with a concentration-dependent diffusion coefficient. PMID:26018995

  19. Effects of Experimental Fasciola gigantica Infection on Serum Testosterone Profiles in Relationship to Semen Characteristics of Yankasa Ram

    OpenAIRE

    D. Iliyasu; N.P. Chiezey; J.S. Rwuaan; I.U. Ate; J.O. Ajanusi; Okubanjo, O. O.; E.K Bawa

    2014-01-01

    This study was designed to evaluate the effects of Fasciolosis on serum testosterone profiles and semen characteristics of Yankasa rams. Twelve, apparently healthy, Yankasa rams aged 18-24 months were randomly divided into two groups (infected group A and control group B) with seven and five rams, respectively. The rams werekept under intensive management in different pens throughout the study period. Group A rams were inoculated with 800 metacecariae orally and monitored for 12 weeks Post In...

  20. Profiling the local carrier concentration and dopant distribution across a semiconductor quantum dot

    Science.gov (United States)

    Walrath, J. C.; Chang, A. S.; Lin, Y. H.; Huang, S.; Goldman, R. S.

    We profile the local carrier concentration, n, across epitaxial InAs/GaAs quantum dots (QDs) consisting of 3D islands on top of a 2D alloy layer. We use scanning thermoelectric microscopy to profile the temperature gradient-induced voltage, which is converted to a profile of the local Seebeck coefficient, S. The S profile is then converted to a conduction band-edge profile and compared with Poisson-Schrodinger band-edge simulations. Our combined computational-experimental approach suggests a reduced carrier concentration in the QD center in comparison to that of the 2D alloy layer. We further use 3D atom probe tomography, which enables 3D imaging with a few Angstrom resolution, to profile the distribution of Si dopants. We discuss the correlation between the Si dopant distribution and the observed carrier concentration profile.

  1. Hemograma de cães submetidos ao envenenamento experimental por Tityus serrulatus Canine blood profile after experimental envenomation by Tityus serrulatus

    Directory of Open Access Journals (Sweden)

    E.L. Ribeiro

    2009-02-01

    Full Text Available Avaliou-se o hemograma de 12 cães adultos, saudáveis (14,2±5,4kg após a inoculação de veneno do escorpião amarelo (Tityus serrulatus. Os animais foram distribuídos em dois grupos (G, com seis em cada: os do GI foram usados como controle e receberam 0,5mL de salina tamponada com fosfato (PBS por via subcutânea (SC na face medial da coxa esquerda (FMCE, e os do GII receberam veneno liofilizado do T. serrulatus (250µg/kg diluído em PBS por via SC na FMCE. Foram realizadas colheitas de sangue com anticoagulante EDTA a 10% antes da inoculação do veneno (T0 e após 2h, (T1, 6h (T2, 12h (T3, 24h (T4, 48h (T5 e 72h (T6, para contagem de eritrócitos, leucócitos e plaquetas em aparelho contador eletrônico e esfregaços sanguíneos para contagem diferencial de leucócitos. Houve aumento significativo (PThe canine blood profile after scorpion envenomation was evaluated using 12 healthy mongrel male dogs (14.2±5.4kg distributed in two groups, with six animals in each: group I (control group and group II (venom group. The lyophilized yellow scorpion (Tityus serrulatus venom (250µg/kg diluted in 0.5mL phosphate buffered saline (PBS was given to group II animals by subcutaneous injection, in the medial face of the left thigh. Group I animals received only 0.5mL of PBS, by subcutaneous injection, in the medial face of the left thigh. Blood samples were collected with EDTA before (T0 and 2 (T1, 6 (T2, 12 (T3, 24 (T4, 48 (T5, and 72h (T6 after envenomation. Significant increases (P<0.05 in erythrocytes counting, hematocrit and hemoglobin concentration, 2 and 6h after envenomation were observed. Leukocytosis with significant increases (P<0.05 of neutrophils and lymphocytes 2 and 6h after envenomation was found. Then, T. serrulatus venom may induce alterations in blood profile in dogs, probably due to spleen contraction evoked by pain and catecholamines releasing.

  2. Compton profile study and electronic properties of tantalum diboride

    International Nuclear Information System (INIS)

    We have reported the first-ever experimental Compton profile (CP) of TaB2 using 20 Ci137Cs Compton spectrometer. To compare the experimental data, we have also computed the theoretical CPs using density functional theory (DFT) and hybridization of DFT and Hartree–Fock (HF) within linear combination of the atomic orbitals (LCAO) method. In addition, we have reported energy bands and density of states of TaB2 using LCAO and full potential-linearized augmented plane wave (FP-LAPW) methods. A real space analysis of CP of TaB2 confirms its metallic character which is in tune with the cross-overs of Fermi level by energy bands and Fermi surface topology. A comparison of equal-valence-electron-density (EVED) experimental profiles of isoelectronic TaB2 and NbB2 show more covalent (or less ionic) character of TaB2 than that of NbB2 which is in agreement with available ionicity data. - Highlights: ► Reported first-ever experimental Compton profile (CP) of TaB2. ► Interpreted experimental CP using theoretical CP within density functional theory. ► Analyzed equal-valence-electron-density experimental CPs of TaB2 and NbB2. ► Established metallic character by taking Fourier transform of experimental CP. ► Reported energy bands, DOS and Fermi surface of TaB2 using LCAO and FP-LAPW

  3. Experimental Study of the Composition and Structure of Granular Media in the Shear Bands Based on the HHC-Granular Model

    Directory of Open Access Journals (Sweden)

    Guang-jin Wang

    2014-01-01

    Full Text Available The researchers cannot control the composition and structure of coarse grained soil in the indoor experiment because the granular particles of different size have the characteristics of random distribution and no sorting. Therefore, on the basis of the laboratory tests with the coarse grained soil, the HHC-Granular model, which could simulate the no sorting and random distribution of different size particles in the coarse-grained soil, was developed by use of cellular automata method. Meanwhile, the triaxial numerical simulation experiments of coarse grained soil were finished with the different composition and structure soil, and the variation of shear strength was discussed. The results showed that the internal friction angle was likely to reduce with the increasing of gravel contents in the coarse-grained soil, but the mean internal friction angle significantly increased with the increment of gravel contents. It indicated that the gravel contents of shear bands were the major factor affecting the shear strength.

  4. The profile of middle school students in experimental planning skills through inquiry training model on heat transfer

    Science.gov (United States)

    Darwis, Rahmiati; Rustaman, Nuryani Y.

    2016-02-01

    This study aimed to describe the experimental planning skills in middle school students on the topic of heat transfer through Inquiry Training Model (ITM) with laboratory activity. This research used descriptive method with A number of middle school students (n=21) in Bone was involved as participants in this study. Data was collected through observation sheets on science process skills. Research finding shows that the experimental planning skills of the participants varied in a sense of groups and all was well developed (> 90%) after having experience learning on heat transfer through ITM. It can be shown in the data collected phase through experimentation and filled-in student worksheet, Topic of heat transfer was the last period of the whole heat topic carried out through ITM. The students carried out the investigation without following the experimental design presented in the student' workbook, instead they were active in discussions to determine the tools and materials, as well as setting the pace of work independently based on the agreement in their group, so they have had experience in planning experiments. This activity shows the various students 'creativity in designing an experiment and from that those creations the students' like scientists in proving, discovery and developing invention potency that have been there before.

  5. Experimental demonstration and modeling of the internal light scattering profile within solar cells due to random dielectric scatterers

    Science.gov (United States)

    Murray, Joseph; Munday, Jeremy N.

    2016-01-01

    Many photovoltaic technologies are shifting toward thin-film devices to simultaneously reduce costs and improve carrier collection efficiencies; however, the need for nearly complete light absorption within the semiconductor to achieve large short-circuit currents constrains this thickness reduction. Light trapping strategies can be employed to increase absorption in thinner devices. Random scattering coatings offer a simple, cost-effective way to increase solar cell absorption without the drawback of increased surface recombination or reduced bandwidth that occurs when using surface texturing or gratings. However, coatings that show excellent performance as scatterers in free space generally do not enhance device absorption as much as an ideal Lambertian scatterer. Here, we present an experimental technique and theoretical model that accurately describes the absorption improvement that is achievable with coatings based on random ensembles of dielectric scatterers. We find that the ideal Lambertian model substantially overestimates the experimental scattering results, but significant path length enhancements are still achievable. The experimental techniques presented here should enable the testing of various optical models that attempt to surpass the ray optics light trapping limit, which have in many cases been hindered by the experimental difficulty of coupling the incident light into the optical modes of the absorber.

  6. Revised vibrational band assignments for the experimental IR and Raman spectra of 2,3,4-trifluorobenzonitrile based on ab initio, DFT and normal coordinate calculations

    Science.gov (United States)

    Hiremath, C. S.; Kalkoti, G. B.; Aralakkanavar, M. K.

    2009-09-01

    In the present study, a systematic vibrational spectroscopic investigation for the experimental IR and Raman spectra of 2,3,4-trifluorobenzonitrile (TFB), aided by electronic structure calculations has been carried out. The electronic structure calculations - ab initio (RHF) and hybrid density functional methods (B3LYP) - have been performed with 6-31G* basis set. Molecular equilibrium geometries, electronic energies, IR intensities, harmonic vibrational frequencies, depolarization ratios and Raman activities have been computed. The results of the calculations have been used to simulate IR and Raman spectra for TFB that showed excellent agreement with the observed spectra. Potential energy distribution (PED) and normal mode analysis have also been performed. The assignments proposed based on the experimental IR and Raman spectra have been reviewed. A complete assignment of the observed spectra has been proposed.

  7. Experimental band structure of the nearly half-metallic CuCr{sub 2}Se{sub 4}: an optical and magneto-optical study

    Energy Technology Data Exchange (ETDEWEB)

    Bordacs, S; Kezsmarki, I [Department of Physics, Budapest University of Technology and Economics, and Condensed Matter Research Group of the Hungarian Academy of Sciences, 1111 Budapest (Hungary); Ohgushi, K [Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Tokura, Y, E-mail: bordacs.sandor@wigner.bme.h [Multiferroics Project, ERATO, Japan Science and Technology Agency (JST), Japan, c/o Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan)

    2010-05-15

    Diagonal and off-diagonal optical conductivity spectra have been determined from the measured reflectivity and magneto-optical Kerr effect over a broad range of photon energies in the itinerant ferromagnetic phase of CuCr{sub 2}Se{sub 4} at various temperatures down to T=10 K. Besides the low-energy metallic contribution and the lower-lying charge transfer transition at E{approx}2 eV, a sharp and distinct optical transition was observed in the mid-infrared region around E=0.5 eV with huge magneto-optical activity. This excitation is attributed to a parity allowed transition through the Se-Cr hybridization-induced gap in the majority spin channel. The large off-diagonal conductivity is explained by the high-spin polarization in the vicinity of the Fermi level and the strong spin-orbit interaction for the related charge carriers. The results are discussed in connection with band structure calculations.

  8. Anti-inflammatory effect and prostate gene expression profiling of steryl ferulate on experimental rats with non-bacterial prostatitis.

    Science.gov (United States)

    Hu, Yinzhou; Xiong, Lina; Huang, Weisu; Cai, Huafang; Luo, Yanxi; Zhang, Ying; Lu, Baiyi

    2014-06-01

    Steryl ferulate (SF) is a bioactive mixture extracted from rice bran and shows higher inhibitory activity against inflammation than the corresponding free sterols. In this study, the aim was to investigate the anti-inflammatory effect and prostate gene expression profiling of SF using a Xiaozhiling-induced non-bacterial prostatitis (NBP) rat model. The anti-inflammatory effect was evaluated by prostate weight, prostate index, acid phosphatase, density of lecithin corpuscles (DLC), white blood cell count (WBC), and prostatic histologic section. Prostate gene expression profiling was assessed by a cDNA microarray and validated by quantitative real-time PCR of five selected genes. Pathway analysis and Gene ontology (GO) analysis were applied to determine the roles of these differentially expressed genes involved in these biological pathways or GO terms. SF treatment could significantly inhibit prostate weight, prostate index, total acid phosphatase, prostatic acid phosphatase and WBC, suppress the severity of histological lesion and increase the DLC. Compared with the control group, the SF treatment group contained 238 up-regulated genes and 111 down-regulated genes. GO analysis demonstrated that the most significant expression genes were closely related to the terms of fibrinolysis, inflammatory response, high-density lipoprotein particle, protein-lipid complex, enzyme inhibitor activity, peptidase inhibitor activity and others. Canonical pathway analysis indicated five pathways were significantly regulated, which were associated with inflammation and tumorgenesis. In conclusion, SF may be used as a health supplement to prevent NBP, in that it could inhibit prostate inflammation in NBP patients by affecting the expression of genes in the related GO terms and pathways. PMID:24686498

  9. The central nervous system environment controls effector CD4+ T cell cytokine profile in experimental allergic encephalomyelitis

    DEFF Research Database (Denmark)

    Krakowski, M L; Owens, T

    1997-01-01

    In experimental allergic encephalomyelitis (EAE), CD4+ T cells infiltrate the central nervous system (CNS). We derived CD4+ T cell lines from SJL/J mice that were specific for encephalitogenic myelin basic protein (MBP) peptides and produced both Th1 and Th2 cytokines. These lines transferred EAE...... to naive mice. Peptide-specific cells re-isolated from the CNS only produced Th1 cytokines, whereas T cells in the lymph nodes produced both Th1 and Th2 cytokines. Mononuclear cells isolated from the CNS, the majority of which were microglia, presented antigen to and stimulated MBP-specific T cell...

  10. Experimental and numerical analysis of the chromatic dispersion dependence upon the actual profile of small core microstructured fibres

    CERN Document Server

    Labonté, Laurent; Pagnoux, Dominique; Louradour, Frédéric; Restoin, Christine; Mélin, Gilles; Burov, Ekatarina

    2010-01-01

    The chromatic dispersion curve of the fundamental mode in small core microstructured fibres (SCMF) is both calculated using a Finite Element Method (FEM) and measured with a low coherence interferometric method. The great sensitivity of the chromatic dispersion to variations of the geometrical parameters of SCMFs (the pitch and the diameter) is pointed out. An excellent agreement is obtained between the numerical and the experimental results over a half micrometer spectral bandwidth [1.1 $\\mu$m-1.6 $\\mu$m].

  11. Experimental investigation of the difference in B-term dominated band broadening between fully porous and porous-shell particles for liquid chromatography using the Effective Medium Theory.

    Science.gov (United States)

    Liekens, Anuschka; Denayer, Joeri; Desmet, Gert

    2011-07-15

    The difference in B-term diffusion between fully porous and porous-shell particles is investigated using the physically sound diffusion equations originating from the Effective Medium Theory (EMT). Experimental data of the B-term diffusion obtained via peak parking measurements on six different commercial particle types have been analyzed (3 porous and 3 non porous). All particles were investigated using the same experimental design and test analytes, over a very broad range of retention factor values. First, the B-term reducing effect of the solid core (inducing an additional obstruction compared to fully porous particles) has been quantified using the Hashin-Shtrikman expression, showing that the presence of a solid core can account for a reduction of about 11% when the core diameter makes up 63% of the total particle diameter (Halo and Poroshell-particles) and a reduction of 16% when the core diameter makes up 73% (Kinetex). Remaining differences can be attributed to differences in the microscopic structure of the meso-porous material (meso-pore diameter, internal porosity or relative void volume). The much lower B-term diffusion of Halo and Kinetex particles compared to the fully porous Acquity particles (some 20-40% difference, of which about 10-15% can be attributed to the presence of the solid core) can hence largely be attributed to the much smaller internal porosity and the smaller pore size of the meso-porous material making up the shell of these particles. PMID:21628063

  12. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    V Subramanian

    2008-04-01

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are formed by removing the substrate material in a periodic manner. This paper also demonstrates that these structures can serve as a non-destructive characterization tool for materials, a duplexor and frequency selective coupler. The paper presents both experimental results and theoretical simulation based on a commercially available finite element methodology for comparison.

  13. Cattle experimentally infected by Anaplasma marginale: Influence of splenectomy on disease pathogenesis, oxidative profile, and antioxidant status.

    Science.gov (United States)

    Doyle, Rovaina L; França, Raqueli T; Oliveira, Camila B; Rezer, João F P; Klafke, Guilherme M; Martins, João R; Santos, Andrea P; do Nascimento, Naíla C; Mesick, Joanne B; Lopes, Sonia T A; Leal, Daniela B R; Da Silva, Aleksandro S; Andrade, Cinthia M

    2016-06-01

    Bovine anaplasmosis is caused by the obligate intraerythrocytic bacteria Anaplasma marginale. These bacteria are transmitted by tick species such as Rhipicephalus (Boophilus) microplus, blood-sucking insects, and fomites (needles, clippers, and other blood contaminated equipment). During the acute phase of infection, animals may develop fever, anemia, jaundice, and hepatosplenomegaly. The aims of this study are to quantify the bacteremia by quantitative PCR in eight naïve calves experimentally infected by A. marginale [splenectomized (n = 4), and intact/non-splenectomized (n = 4)], and to correlate these findings with markers of oxidative stress on days 0, 8, 15, 21 and 23 post-infection. Complete blood counts (CBC) were performed in both groups. Lipid peroxidation was estimated by quantifying thiobarbituric acid reactive substances (TBARS); and non-enzymatic antioxidants were assessed by erythrocyte content of non-protein thiols (NPSH). There were no significant differences in complete blood counts (CBC) between the two groups. However, both groups had a slight decrease on packet cell volume (PCV), erythrocytes and hemoglobin concentration, as well as an increase in total leukocyte counts due to elevated lymphocytes when comparing pre and post-infection with A. marginale. Progressive increase on TBARS levels and concomitant decrease on NPSH content were observed in all animals, without significant differences between splenectomized and intact animals. A positive correlation between bacteremia and TBARS, and a negative correlation between bacteremia and NPSH were observed in both groups with higher correlation for NPSH in splenectomized animals. A negative correlation between TBARS and NPSH levels was observed in both groups indicating lipid peroxidation without a non-enzymatic antioxidant response. The results of experimental infection by A. marginale in cattle showed that bacteremia has an impact on lipid peroxidation regardless of the splenectomy. PMID

  14. Effects of Experimental Fasciola gigantica Infection on Serum Testosterone Profiles in Relationship to Semen Characteristics of Yankasa Ram

    Directory of Open Access Journals (Sweden)

    D. Iliyasu

    2014-10-01

    Full Text Available This study was designed to evaluate the effects of Fasciolosis on serum testosterone profiles and semen characteristics of Yankasa rams. Twelve, apparently healthy, Yankasa rams aged 18-24 months were randomly divided into two groups (infected group A and control group B with seven and five rams, respectively. The rams werekept under intensive management in different pens throughout the study period. Group A rams were inoculated with 800 metacecariae orally and monitored for 12 weeks Post Infection (PI. Clinical signs were manifested 2 weeks PI. Faecal examination revealed Fasciola eggs at week 7 PI in group A. Three mL of blood were collected aseptically via the jugular vein at 30 min interval, weekly between 08:00-9:00am for serum testosterone assay. Testosterone assay was done using ELISA technique. There was significant decrease in testosterone concentration in group A at different time intervals of the weeks of post-infection. The semen analysis showed the lowest mean (±SEM of semen volume, semen motility, semen concentration, of group A, as (0.01±0.0 mL, (3.6±2.4%, (16.1±4.2% compared to group B with mean (±SEM (1.6±0.1 mL, (93.0±1.2%, (440.0±13.0% at week 7 post-infection, respectively. This study revealed that Fasciolosis has a great impact on sheep mainly by diminishing their reproductive efficiency and rendering infected rams infertile. It is concluded that F. gigantica infectionhad advanced effects on testosterone production and semen quality of Yankasa rams.

  15. Three-terminal junctions operating as mixers, frequency doublers and detectors: a broad-band frequency numerical and experimental study at room temperature

    International Nuclear Information System (INIS)

    The frequency response of nanometric T- and Y-shaped three-terminal junctions (TTJs) is investigated experimentally and numerically. In virtue of the parabolic down-bending of the output voltage of the central branch obtained at room temperature under a push–pull fashion input, we analyse the low-frequency performance (<1 MHz) of TTJs operating as mixers, their RF capability as doublers up to 4 GHz and detection at 94 GHz. Special attention is paid to the impedance matching and cut-off frequency of the measurement setup. The numerical study is carried out by means of Monte Carlo simulations. We illustrate the intrinsic functionality of the device as frequency doubler or rectifier up to THz. The role of the width of the central branch on the high-frequency response is also explored, finding different cut-off frequencies for doubling and detection as a consequence of the diverse working principles of both mechanisms and the particular geometry of the TTJs

  16. Experimental Investigation of the Effect of Bow Profiles on Resistance of an Underwater Vehicle in Free Surface Motion

    Institute of Scientific and Technical Information of China (English)

    Mehran Javadi; Mojtaba Dehghan Manshadi; Saeid Kheradmand; Mohammad Moonesun

    2015-01-01

    In this paper, towing tank experiments are conducted to study the behavior of flow on a model of the underwater vehicle with various shapes of bows, i.e. tango and standard bows in free surface motion tests. The total resistances for different Froude numbers are considered experimentally. The towing tank is equipped with a trolley that can operate in through 0.05–6 m/s speed with ±0.02 m/s accuracy. Furthermore, the study is done on hydrodynamic coefficients i.e. total, residual and friction resistance coefficients, and the results are compared. Finally, the study on flow of wave fields around bows is done and wave filed around two bows are compared. The Froude number interval is between 0.099 and 0.349. Blockage fraction for the model is fixed to 0.005 3. The results showed that the residual resistance of the standard bow in 0.19 to 0.3 Froude number is more than the tango bow in surface motion which causes more total resistance for the submarine. Finally, details of wave generated by the bow are depicted and the effects of flow pattern on resistance drag are discussed.

  17. DNA microarray-based experimental strategy for trustworthy expression profiling of the hippocampal genes by astaxanthin supplementation in adult mouse.

    Science.gov (United States)

    Yook, Jang Soo; Shibato, Junko; Rakwal, Randeep; Soya, Hideaki

    2016-03-01

    Naturally occurring astaxantin (ASX) is one of the noticeable carotenoid and dietary supplement, which has strong antioxidant and anti-inflammatory properties, and neuroprotective effects in the brain through crossing the blood-brain barrier. Specially, we are interested in the role of ASX as a brain food. Although ASX has been suggested to have potential benefit to the brain function, the underlying molecular mechanisms and events mediating such effect remain unknown. Here we examined molecular factors in the hippocampus of adult mouse fed ASX diets (0.1% and 0.5% doses) using DNA microarray (Agilent 4 × 44 K whole mouse genome chip) analysis. In this study, we described in detail our experimental workflow and protocol, and validated quality controls with the housekeeping gene expression (Gapdh and Beta-actin) on the dye-swap based approach to advocate our microarray data, which have been uploaded to Gene Expression Omnibus (accession number GSE62197) as a gene resource for the scientific community. This data will also form an important basis for further detailed experiments and bioinformatics analysis with an aim to unravel the potential molecular pathways or mechanisms underlying the positive effects of ASX supplementation on the brain, in particular the hippocampus. PMID:26981356

  18. DNA microarray-based experimental strategy for trustworthy expression profiling of the hippocampal genes by astaxanthin supplementation in adult mouse

    Directory of Open Access Journals (Sweden)

    Jang Soo Yook

    2016-03-01

    Full Text Available Naturally occurring astaxantin (ASX is one of the noticeable carotenoid and dietary supplement, which has strong antioxidant and anti-inflammatory properties, and neuroprotective effects in the brain through crossing the blood–brain barrier. Specially, we are interested in the role of ASX as a brain food. Although ASX has been suggested to have potential benefit to the brain function, the underlying molecular mechanisms and events mediating such effect remain unknown. Here we examined molecular factors in the hippocampus of adult mouse fed ASX diets (0.1% and 0.5% doses using DNA microarray (Agilent 4 × 44 K whole mouse genome chip analysis. In this study, we described in detail our experimental workflow and protocol, and validated quality controls with the housekeeping gene expression (Gapdh and Beta-actin on the dye-swap based approach to advocate our microarray data, which have been uploaded to Gene Expression Omnibus (accession number GSE62197 as a gene resource for the scientific community. This data will also form an important basis for further detailed experiments and bioinformatics analysis with an aim to unravel the potential molecular pathways or mechanisms underlying the positive effects of ASX supplementation on the brain, in particular the hippocampus.

  19. Experimental resolution of deuterium and hydrogen depth profiling with the nuclear reactions D(3He,p)α and p(15N,α,γ)12C

    International Nuclear Information System (INIS)

    In this paper well defined test samples are used to show how the analysis depth and the matrix material influence the depth resolution of nuclear reaction analysis. The reaction D(3He,p)α is used to detect deuterium. By covering 10 nm thin deuterated amorphous carbon (a–C:D) films on silicon with tungsten (ZW = 74) and titanium (ZTi = 22) of various thicknesses between 500 nm and 8 μm the influence of the atomic number and the overlayer thickness on the depth resolution is studied. The most probable depth profiles are calculated from the experimental data with the program NRADC, which implements Bayesian statistics. The resulting apparent layer width of the deuterium containing layer broadens with increasing thickness of the coating and this broadening is more pronounced for coatings with higher Z. These apparent layer widths are a measure for the experimentally achievable depth resolution. Their absolute values are in the same range as the theoretical optimum calculated with RESOLNRA. To investigate the depth resolution of the p(15N,α,γ)12C reaction, a 12 nm thin hydrogenated amorphous carbon (a–C:H) film on silicon and a pure tungsten sample are analysed. The width of the instrument function of this method is deduced from the surface hydrogen peak of the pure tungsten sample. The two methods are compared

  20. Electron momentum density and band structure calculations of {alpha}- and {beta}-GeTe

    Energy Technology Data Exchange (ETDEWEB)

    Vadkhiya, Laxman [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India); Arora, Gunjan [Department of Physics, Techno India NJR Institute of Technology, Udaipur 313002, Rajasthan (India); Rathor, Ashish [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India); Ahuja, B.L., E-mail: blahuja@yahoo.com [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India)

    2011-12-15

    We have measured isotropic experimental Compton profile of {alpha}-GeTe by employing high energy (662 keV) {gamma}-radiation from a {sup 137}Cs isotope. To compare our experiment, we have also computed energy bands, density of states, electron momentum densities and Compton profiles of {alpha}- and {beta}-phases of GeTe using the linear combination of atomic orbitals method. The electron momentum density is found to play a major role in understanding the topology of bands in the vicinity of the Fermi level. It is seen that the density functional theory (DFT) with generalised gradient approximation is relatively in better agreement with the experiment than the local density approximation and hybrid Hartree-Fock/DFT. - Highlights: > Compton profile of {alpha}-GeTe using a 20 Ci {sup 137}Cs Compton spectrometer. > Compared experimental Compton data with density functional theory. > Reported energy bands and density of states of {alpha}- and {beta}-GeTe. > EVED profiles analysed to check the covalent character.

  1. Experimental and Coupled-channels Investigation of the Radiative Properties of the N2 c4 (sup 1)Sigma+(sub u) - X (sup 1)Sigma+(sub g) Band System

    Science.gov (United States)

    Liu, Xianming; Shemansky, Donald E.; Malone, Charles P.; Johnson, Paul V.; Ajello, Joseph M.; Kanik, Isik; Heays, Alan N.; Lewis, Brenton R.; Gibson, Stephen T.; Stark, Glenn

    2008-01-01

    The emission properties of the N2 c(sup prime)(sub 4) (sup 1)Sigma+(sub u) - Chi (sup 1)Sigma+(sub g) band system have been investigated in a joint experimental and coupled-channels theoretical study. Relative intensities of the c(sup prime)(sub 4) (sup 1)Sigma+(sub u)(0) - Chi (sup 1)Sigma+(sub g)(v(sub i)) transitions, measured via electron-impact-induced emission spectroscopy, are combined with a coupled-channel Schroedinger equation (CSE) model of the N2 molecule, enabling determination of the diabatic electronic transition moment for the c(sup prime)(sub 4) (sup 1)Sigma+(sub u) - Chi (sup 1)Sigma+(sub g) system as a function of internuclear distance. The CSE probabilities are further verified by comparison with a high-resolution experimental spectrum. Spontaneous transition probabilities of the c(sup prime)(sub 4) (sup 1)Sigma+(sub u) - Chi (sup 1)Sigma+(sub g) modeling atmospheric emission, can now be calculated reliably.

  2. The new real-time measurement capabilities of the profiling TARA radar

    NARCIS (Netherlands)

    Unal, C.M.H.; Dufournet, Y.; Otto, T.; Russchenberg, H.W.J.

    2012-01-01

    In the past 10 years, the S-band FM-CW TARA (Transportable Atmospheric RAdar), placed at the Cabauw Experimental Site for Atmospheric Research (CESAR), provided in real-time vertical profiles of the Doppler moments. Classical spectral processing was carried out. The polarimetric and multi-beam measu

  3. Electronic structure and Compton profiles of CdO and HgO

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, Gopal; Raykar, Veera [Department of Physics, Mewar University, Chittorgarh 312001, Rajasthan (India); Tiwari, Shailja; Dashora, Alpa; Ahuja, Babu Lal [Department of Physics, University College of Science, M. L. Sukhadia University, Udaipur 313002, Rajasthan (India)

    2011-01-15

    We present the first ever measured experimental electron momentum densities of CdO and HgO at an intermediate resolution using 20 Ci{sup 137}Cs Compton spectrometer. The measurements are compared with the theoretical Compton profiles using density functional theory (DFT) and hybridization of DFT with the Hartree-Fock as embodied in linear combination of atomic orbitals (LCAO) scheme. In addition, we have also calculated the energy bands and density of states using the full potential linearized augmented plane wave method and the LCAO schemes. It is seen that the hybridization scheme, which overestimates the band gap, gives a better agreement with the experimental profiles. A comparative nature of bonding is also discussed in terms of equal-valence-electron-density scaling of both the experimental profiles and valence charge densities. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Compton profiles and electronic properties of TiB2

    International Nuclear Information System (INIS)

    In this paper, we report the experimental Compton profile (CP) of TiB2 using high energy 137Cs γ-rays Compton spectrometer. To interpret the experimental momentum density, we have calculated the CPs using Hartree-Fock (HF), density functional theory (DFT) and hybridization of DFT and HF within linear combination of atomic orbitals. The theoretical profile with generalized gradient approximation is found to be relatively in better agreement with the experimental profile. A sharp valley in density of states and hence the pseudogap near the Fermi energy is attributed to hybridization of Ti-3d and B-2p states and almost reverse trend of energy bands below and above the Fermi energy

  5. In utero exposure to butyl benzyl phthalate induces modifications in the morphology and the gene expression profile of the mammary gland: an experimental study in rats

    Directory of Open Access Journals (Sweden)

    Russo Irma H

    2011-01-01

    Full Text Available Abstract Background Environmental estrogens are exogenous estrogen-mimicking compounds that can interfere with endogenous endocrine systems. Several of these endocrine disruptors have been shown to alter normal development and influence tumorigenesis in experimental models. N-butyl benzyl phthalate (BBP, a widely used plasticizer, is a well-known endocrine disruptor. The aim of this study was to elucidate the effect of prenatal exposure to BBP on the morphology, proliferative index, and genomic signature of the rat mammary gland at different ages. Methods In utero exposure was performed by gavage of pregnant Sprague Dawley CD rats with 120mg or 500mg BBP/kg/day from day 10 post-conception to delivery. Female litters were euthanized at 21, 35, 50 and 100 days. The morphology and proliferative index of the mammary gland were studied from whole mount preparations and BrdU incorporation, respectively. Gene expression profile was assessed by microarrays. Several genes found differentially expressed and related to different functional categories were further validated by real time RT-PCR. Results Prenatal exposure of BBP induced delayed vaginal opening and changes in the post-natal mammary gland long after the end of the treatment, mainly by 35 days of age. Exposure to the high dose resulted in modifications in architecture and proliferative index of the mammary gland, mostly affecting the undifferentiated terminal end buds. Moreover, the expression profiles of this gland in the exposed rats were modified in a dose-dependent fashion. Analysis of functional categories showed that modified genes were related to immune function, cell signaling, proliferation and differentiation, or metabolism. Conclusions Our data suggest that in utero exposure to BBP induced a delayed pubertal onset and modified morphology of the mammary gland. These alterations were accompanied by modifications in gene expression previously associated with an increased susceptibility

  6. Experimental determination of the lateral dose response functions of detectors to be applied in the measurement of narrow photon-beam dose profiles

    Science.gov (United States)

    Poppinga, D.; Meyners, J.; Delfs, B.; Muru, A.; Harder, D.; Poppe, B.; Looe, HK

    2015-12-01

    This study aims at the experimental determination of the detector-specific 1D lateral dose response function K(x) and of its associated rotational symmetric counterpart K(r) for a set of high-resolution detectors presently used in narrow-beam photon dosimetry. A combination of slit-beam, radiochromic film, and deconvolution techniques served to accomplish this task for four detectors with diameters of their sensitive volumes ranging from 1 to 2.2 mm. The particular aim of the experiment was to examine the existence of significant negative portions of some of these response functions predicted by a recent Monte-Carlo-simulation (Looe et al 2015 Phys. Med. Biol. 60 6585-607). In a 6 MV photon slit beam formed by the Siemens Artiste collimation system and a 0.5 mm wide slit between 10 cm thick lead blocks serving as the tertiary collimator, the true cross-beam dose profile D(x) at 3 cm depth in a large water phantom was measured with radiochromic film EBT3, and the detector-affected cross-beam signal profiles M(x) were recorded with a silicon diode, a synthetic diamond detector, a miniaturized scintillation detector, and a small ionization chamber. For each detector, the deconvolution of the convolution integral M(x)  =  K(x)  ∗  D(x) served to obtain its specific 1D lateral dose response function K(x), and K(r) was calculated from it. Fourier transformations and back transformations were performed using function approximations by weighted sums of Gaussian functions and their analytical transformation. The 1D lateral dose response functions K(x) of the four types of detectors and their associated rotational symmetric counterparts K(r) were obtained. Significant negative curve portions of K(x) and K(r) were observed in the case of the silicon diode and the diamond detector, confirming the Monte-Carlo-based prediction (Looe et al 2015 Phys. Med. Biol. 60 6585-607). They are typical for the perturbation of the secondary electron field by a detector with

  7. Experimental determination of the lateral dose response functions of detectors to be applied in the measurement of narrow photon-beam dose profiles

    International Nuclear Information System (INIS)

    This study aims at the experimental determination of the detector-specific 1D lateral dose response function K(x) and of its associated rotational symmetric counterpart K(r) for a set of high-resolution detectors presently used in narrow-beam photon dosimetry. A combination of slit-beam, radiochromic film, and deconvolution techniques served to accomplish this task for four detectors with diameters of their sensitive volumes ranging from 1 to 2.2 mm. The particular aim of the experiment was to examine the existence of significant negative portions of some of these response functions predicted by a recent Monte-Carlo-simulation (Looe et al 2015 Phys. Med. Biol. 60 6585–607).In a 6 MV photon slit beam formed by the Siemens Artiste collimation system and a 0.5 mm wide slit between 10 cm thick lead blocks serving as the tertiary collimator, the true cross-beam dose profile D(x) at 3 cm depth in a large water phantom was measured with radiochromic film EBT3, and the detector-affected cross-beam signal profiles M(x) were recorded with a silicon diode, a synthetic diamond detector, a miniaturized scintillation detector, and a small ionization chamber. For each detector, the deconvolution of the convolution integral M(x)  =  K(x)  ∗  D(x) served to obtain its specific 1D lateral dose response function K(x), and K(r) was calculated from it. Fourier transformations and back transformations were performed using function approximations by weighted sums of Gaussian functions and their analytical transformation.The 1D lateral dose response functions K(x) of the four types of detectors and their associated rotational symmetric counterparts K(r) were obtained. Significant negative curve portions of K(x) and K(r) were observed in the case of the silicon diode and the diamond detector, confirming the Monte-Carlo-based prediction (Looe et al 2015 Phys. Med. Biol. 60 6585–607). They are typical for the perturbation of the secondary electron field by a detector

  8. Detection of the bright band with a vertically pointing k-band radar

    OpenAIRE

    Thomas Pfaff; Alexander Engelbrecht; Jochen Seidel

    2014-01-01

    Quantitative precipitation estimation based on weather radar data suffers from a variety of errors. During stratiform events, a region of enhanced reflectivity, called the bright band, leads to large positive biases in the precipitation estimates when compared with ground measurements. The identification of the bright band is an important step when trying to correct weather radar data for this effect. In this study we investigate three different methods to identify the bright band from profil...

  9. Impurity effects on the band structure of one-dimensional photonic crystals: experiment and theory

    International Nuclear Information System (INIS)

    We study the effects of single impurities on the transmission in microwave realizations of the photonic Kronig-Penney model, consisting of arrays of Teflon pieces alternating with air spacings in a microwave guide. As only the first propagating mode is considered, the system is essentially one-dimensional (1D) obeying the Helmholtz equation. We derive analytical closed form expressions from which the band structure, frequency of defect modes and band profiles can be determined. These agree very well with experimental data for all types of single defects considered (e.g. interstitial and substitutional) and show that our experimental set-up serves to explore some of the phenomena occurring in more sophisticated experiments. Conversely, based on the understanding provided by our formulae, information about the unknown impurity can be determined by simply observing certain features in the experimental data for the transmission. Further, our results are directly applicable to the closely related quantum 1D Kronig-Penney model

  10. Impurity effects on the band structure of one-dimensional photonic crystals: Experiment and theory

    CERN Document Server

    Luna-Acosta, G A; Kuhl, U; Stoeckmann, H -J

    2007-01-01

    We study the effects of single impurities on the transmission in microwave realizations of the photonic Kronig-Penney model, consisting of arrays of Teflon pieces alternating with air spacings in a microwave guide. As only the first propagating mode is considered, the system is essentially one dimensional obeying the Helmholtz equation. We derive analytical closed form expressions from which the band structure, frequency of defect modes, and band profiles can be determined. These agree very well with experimental data for all types of single defects considered (e. g. interstitial, substitutional) and shows that our experimental set-up serves to explore some of the phenomena occurring in more sophisticated experiments. Conversely, based on the understanding provided by our formulas, information about the unknown impurity can be determined by simply observing certain features in the experimental data for the transmission. Further, our results are directly applicable to the closely related quantum 1D Kronig-Penn...

  11. Effect of particle pinch on the fusion performance and profile features of an international thermonuclear experimental reactor-like fusion reactor

    Science.gov (United States)

    Wang, Shijia; Wang, Shaojie

    2015-04-01

    The evolution of the plasma temperature and density in an international thermonuclear experimental reactor (ITER)-like fusion device has been studied by numerically solving the energy transport equation coupled with the particle transport equation. The effect of particle pinch, which depends on the magnetic curvature and the safety factor, has been taken into account. The plasma is primarily heated by the alpha particles which are produced by the deuterium-tritium fusion reactions. A semi-empirical method, which adopts the ITERH-98P(y,2) scaling law, has been used to evaluate the transport coefficients. The fusion performances (the fusion energy gain factor, Q) similar to the ITER inductive scenario and non-inductive scenario (with reversed magnetic shear) are obtained. It is shown that the particle pinch has significant effects on the fusion performance and profiles of a fusion reactor. When the volume-averaged density is fixed, particle pinch can lower the pedestal density by ˜30 % , with the Q value and the central pressure almost unchanged. When the particle source or the pedestal density is fixed, the particle pinch can significantly enhance the Q value by 60 % , with the central pressure also significantly raised.

  12. Effect of particle pinch on the fusion performance and profile features of an international thermonuclear experimental reactor-like fusion reactor

    International Nuclear Information System (INIS)

    The evolution of the plasma temperature and density in an international thermonuclear experimental reactor (ITER)-like fusion device has been studied by numerically solving the energy transport equation coupled with the particle transport equation. The effect of particle pinch, which depends on the magnetic curvature and the safety factor, has been taken into account. The plasma is primarily heated by the alpha particles which are produced by the deuterium-tritium fusion reactions. A semi-empirical method, which adopts the ITERH-98P(y,2) scaling law, has been used to evaluate the transport coefficients. The fusion performances (the fusion energy gain factor, Q) similar to the ITER inductive scenario and non-inductive scenario (with reversed magnetic shear) are obtained. It is shown that the particle pinch has significant effects on the fusion performance and profiles of a fusion reactor. When the volume-averaged density is fixed, particle pinch can lower the pedestal density by ∼30%, with the Q value and the central pressure almost unchanged. When the particle source or the pedestal density is fixed, the particle pinch can significantly enhance the Q value by  60%, with the central pressure also significantly raised

  13. Hematological and biochemical profiles of rats submitted to experimental poisoning with Tityus serrulatus venom Perfis hematológicos de ratos submetidos ao envenenamento escorpiônico experimental por Tityus serrulatus

    Directory of Open Access Journals (Sweden)

    M.C.L. Pinto

    2010-04-01

    Full Text Available The hematological and biochemical profiles of newly weaned rats submitted to experimental poisoning with T. serrulatus venom were evaluated. Fifteen recently weaned male Wistar rats (mean weight 130g were distributed into three equal groups (n = 5. Animals in the control group (group A received a subcutaneous injection of 400μL of ultra-pure water, while those in the experimental groups received, by identical route, 400μL of a solution containing 100μg (group B or 450μg (group C of scorpion venom dissolved in ultra-pure water. Red blood cells indexes, and differential leukocyte and total platelet counts were determined, together with levels of serum glucose, urea, creatinine, lactic dehydrogenase, aspartate aminotransferase, amylase, insulin, and cortisol. No significant differences between the control and experimental groups regarding red blood cells indexes were found. In contrast, significant increases (PAvaliaram-se os perfis hematológico e bioquímico de ratos recém-desmamados submetidos ao envenenamento experimental com veneno de Tityus serrulatus. Quinze ratos Wistar machos, média de peso de 130g, foram distribuídos aleatoriamente em três grupos (n = 5. Os animais do grupo-controle A foram inoculados com 400μL de água ultrapura, os do grupo experimental B receberam 400μL de uma solução contendo 100μg de veneno e os do grupo experimental C receberam 400μL de uma solução contendo 450μg de veneno. Foram determinados os índices da série vermelha, a contagem total e diferencial dos leucócitos e a contagem total de plaquetas, bem como os níveis da desidrogenase lática, aspartato aminotransferase, amilase, glicose, ureia, creatinina, cortisol e insulina. Não houve diferenças significativas entre o grupo-controle e os experimentais com relação aos índices da série vermelha. Foram observados aumentos significativos (P<0,05 no número de neutrófilos, linfócitos e monócitos nos ratos dos grupos B e C, enquanto o n

  14. Experimental Study on Multi-Band and Multi-Polarization Characteristics of Sea Clutter%多波段多极化海杂波特性的实验研究

    Institute of Scientific and Technical Information of China (English)

    康士峰; 葛德彪; 罗贤云; 张忠治

    2000-01-01

    It is well known that the study of sea clutter characteristics is very important for radar and microwave remote sensing. The multi-band (S, C, X, Ku ) and multi-polarization characteristics of sea clutter measured based on the vector metwork analyzer HP8720C are described in this paper. The measureing system, experimental description and methods of data processing are included. The relationship between clutter characteristics (scatter coefficent, doppler spectrum) and frequency, polarization incident angle (including low-grazing angle) are obtained and some typical results are given.%长期以来,海杂波特性研究一直是雷达和微波遥感界普遍关心的问题。本文讨论基于矢量网络分析仪组建的波谱计对海杂波特性所进行的多波段(S,C,X,Ku)多极化测量,包括测量系统、实验描述和数据处理方法,通过数据分析得到不同海态下杂波特性(散射系数、多普勒谱等)随频率、极化和人射角(含小擦地角)的变化关系并给出一些典型结果。

  15. Cytokine mRNA profiles in bronchoalveolar cells of piglets experimentally infected in utero with with porcine reproductive and respiratory syndrome virus: Association of sustained expression of IFN-gamma and IL-10 after viral clearance

    DEFF Research Database (Denmark)

    Johnsen, C.K.; Bøtner, Anette; Kamstrup, Søren; Lind, Peter; Nielsen, J.

    2002-01-01

    An experimental model was used to investigate mRNA cytokine profiles in bronchoalvolar cells (BALC) from piglets, infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV). The BALC's were analyzed for the cytokines TNF-alpha, IFN-gamma, IL-8, IL-10, and IL-12(p40) by real...

  16. Cytokine mRNA profiles in bronchoalveolar cells of piglets experimentally infected in utero with porcine reproductive and respiratory syndrome virus: Association of sustained expression of IFN-gamma and IL-10 after viral clearance

    DEFF Research Database (Denmark)

    Johnsen, C. K.; Bøtner, Anette; Kamstrup, Søren; Lind, Peter; Nielsen, Jens

    2002-01-01

    An experimental model was used to investigate mRNA cytokine profiles in bronchoalvolar cells (BALC) from piglets, infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV). The BALC's were analyzed for the cytokines TNF-alpha, IFN-gamma, IL-8, IL-10, and IL-12(p40) by real...

  17. Semiconductor resonator solitons above band gap

    OpenAIRE

    Taranenko, V. B.; Weiss, C. O.; Stolz, W.

    2001-01-01

    We show experimentally the existence of bright and dark spatial solitons in semiconductor resonators for excitation above the band gap energy. These solitons can be switched on, both spontaneously and with address pulses, without the thermal delay found for solitons below the band gap which is unfavorable for applications. The differences between soliton properties above and below gap energy are discussed.

  18. Surface Brightness Profiles of Seyfert Galaxies

    CERN Document Server

    Tugay, A V

    2014-01-01

    We built r-band surface brightness profiles by SDSS data for 16 Seyfert galaxies observed in Crimean Astrophysical Observatory. Obtained profiles can be used for finding more accurate lightcurves for these galaxies.

  19. Dual band metamaterial perfect absorber based on artificial dielectric "molecules".

    Science.gov (United States)

    Liu, Xiaoming; Lan, Chuwen; Li, Bo; Zhao, Qian; Zhou, Ji

    2016-01-01

    Dual band metamaterial perfect absorbers with two absorption bands are highly desirable because of their potential application areas such as detectors, transceiver system, and spectroscopic imagers. However, most of these dual band metamaterial absorbers proposed were based on resonances of metal patterns. Here, we numerically and experimentally demonstrate a dual band metamaterial perfect absorber composed of artificial dielectric "molecules" with high symmetry. The artificial dielectric "molecule" consists of four "atoms" of two different sizes corresponding to two absorption bands with near unity absorptivity. Numerical and experimental absorptivity verify that the dual-band metamaterial absorber is polarization insensitive and can operate in wide-angle incidence. PMID:27406699

  20. ASP4058, a novel agonist for sphingosine 1-phosphate receptors 1 and 5, ameliorates rodent experimental autoimmune encephalomyelitis with a favorable safety profile.

    Directory of Open Access Journals (Sweden)

    Rie Yamamoto

    Full Text Available Sphingosine-1-phosphate (S1P is a biologically active sphingolipid that acts through the members of a family of five G protein-coupled receptors (S1P1-S1P5. S1P1 is a major regulator of lymphocyte trafficking, and fingolimod, whose active metabolite fingolimod phosphate acts as a nonselective S1P receptor agonist, exerts its immunomodulatory effect, at least in part, by regulating the lymphocyte trafficking by inducing down regulation of lymphocyte S1P1. Here, we detail the pharmacological profile of 5-{5-[3-(trifluoromethyl-4-{[(2S-1,1,1-trifluoropropan-2-yl]oxy}phenyl]-1,2,4-oxadiazol-3-yl}-1H-benzimidazole (ASP4058, a novel next-generation S1P receptor agonist selective for S1P1 and S1P5. ASP4058 preferentially activates S1P1 and S1P5 compared with S1P2, 3, 4 in GTPγS binding assays in vitro. Oral administration of ASP4058 reduced the number of peripheral lymphocytes and inhibited the development of experimental autoimmune encephalomyelitis (EAE in Lewis rats. Further, ASP4058 prevented relapse of disease in a mouse model of relapsing-remitting EAE. Although these immunomodulatory effects were comparable to those of fingolimod, ASP4058 showed a wider safety margin than fingolimod for bradycardia and bronchoconstriction in rodents. These observations suggest that ASP4058 represents a new therapeutic option for treating multiple sclerosis that is safer than nonselective S1P receptor agonists such as fingolimod.

  1. Socioeconomic conditions in cultural communities: The Nez Perce Tribe, the confederated Tribes of the Umatilla Indian Reservation and the confederated tribes and bands of the Yakima Indian Nation: Interim profile report

    International Nuclear Information System (INIS)

    A series of BWIP Socioeconomic Profile Reports are being prepared. This report is one of the first set of five separate BWIP Profile Reports, which cover: economic/demographic conditions; fiscal conditions; housing characteristics; public services and facilities; and socioeconomic conditions in cultural communities. The BWIP Socioeconomic Profile Reports are designed to provide information about the characteristics of the communities in which socioeconomic impacts from BWIP may occur. The Profile Reports present a compilation of historical information about socioeconomic conditions in the affected communities. These reports are designed to provide a transition between the BWIP EA, published in 1986, the Monitoring Reports, and other technical reports associated with the BWIP SMMP and CSP. The principal objectives of the Profile Reports are to update the DOE BWIP socioeconomic database by compiling available secondary and primary data and to make this information available to both the DOE program and other interested parties. The initial Profile Reports will help identify the need for additional data. The database developed for the profiles will assemble socioeconomic data in a uniform, readily accessible format. 16 refs., 1 fig., 17 tabs

  2. Calculation of temperature distribution in adiabatic shear band based on gradient-dependent plasticity

    Institute of Scientific and Technical Information of China (English)

    王学滨

    2004-01-01

    A method for calculation of temperature distribution in adiabatic shear band is proposed in terms of gradient-dependent plasticity where the characteristic length describes the interactions and interplaying among microstructures. First, the increment of the plastic shear strain distribution in adiabatic shear band is obtained based on gradient-dependent plasticity. Then, the plastic work distribution is derived according to the current flow shear stress and the obtained increment of plastic shear strain distribution. In the light of the well-known assumption that 90% of plastic work is converted into the heat resulting in increase in temperature in adiabatic shear band, the increment of the temperature distribution is presented. Next, the average temperature increment in the shear band is calculated to compute the change in flow shear stress due to the thermal softening effect. After the actual flow shear stress considering the thermal softening effect is obtained according to the Johnson-Cook constitutive relation, the increment of the plastic shear strain distribution, the plastic work and the temperature in the next time step are recalculated until the total time is consumed. Summing the temperature distribution leads to rise in the total temperature distribution. The present calculated maximum temperature in adiabatic shear band in titanium agrees with the experimental observations. Moreover, the temperature profiles for different flow shear stresses are qualitatively consistent with experimental and numerical results. Effects of some related parameters on the temperature distribution are also predicted.

  3. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.;

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory are co...

  4. Flat Band Quastiperiodic Lattices

    Science.gov (United States)

    Bodyfelt, Joshua; Flach, Sergej; Danieli, Carlo

    2014-03-01

    Translationally invariant lattices with flat bands (FB) in their band structure possess irreducible compact localized flat band states, which can be understood through local rotation to a Fano structure. We present extension of these quasi-1D FB structures under incommensurate lattices, reporting on the FB effects to the Metal-Insulator Transition.

  5. Experimental Study of the Flexural and Compression Performance of an Innovative Pultruded Glass-Fiber-Reinforced Polymer-Wood Composite Profile

    Science.gov (United States)

    Qi, Yujun; Xiong, Wei; Liu, Weiqing; Fang, Hai; Lu, Weidong

    2015-01-01

    The plate of a pultruded fiber-reinforced polymer or fiber-reinforced plastic (FRP) profile produced via a pultrusion process is likely to undergo local buckling and cracking along the fiber direction under an external load. In this study, we constructed a pultruded glass-fiber-reinforced polymer-light wood composite (PGWC) profile to explore its mechanical performance. A rectangular cross-sectional PGWC profile was fabricated with a paulownia wood core, alkali-free glass fiber filaments, and unsaturated phthalate resin. Three-point bending and short column axial compression tests were conducted. Then, the stress calculation for the PGWC profile in the bending and axial compression tests was performed using the Timoshenko beam theory and the composite component analysis method to derive the flexural and axial compression rigidity of the profile during the elastic stress stage. The flexural capacity for this type of PGWC profile is 3.3-fold the sum of the flexural capacities of the wood core and the glass-fiber-reinforced polymer (GFRP) shell. The equivalent flexural rigidity is 1.5-fold the summed flexural rigidity of the wood core and GFRP shell. The maximum axial compressive bearing capacity for this type of PGWC profile can reach 1.79-fold the sum of those of the wood core and GFRP shell, and its elastic flexural rigidity is 1.2-fold the sum of their rigidities. These results indicate that in PGWC profiles, GFRP and wood materials have a positive combined effect. This study produced a pultruded composite material product with excellent mechanical performance for application in structures that require a large bearing capacity. PMID:26485431

  6. Experimental Study of the Flexural and Compression Performance of an Innovative Pultruded Glass-Fiber-Reinforced Polymer-Wood Composite Profile.

    Science.gov (United States)

    Qi, Yujun; Xiong, Wei; Liu, Weiqing; Fang, Hai; Lu, Weidong

    2015-01-01

    The plate of a pultruded fiber-reinforced polymer or fiber-reinforced plastic (FRP) profile produced via a pultrusion process is likely to undergo local buckling and cracking along the fiber direction under an external load. In this study, we constructed a pultruded glass-fiber-reinforced polymer-light wood composite (PGWC) profile to explore its mechanical performance. A rectangular cross-sectional PGWC profile was fabricated with a paulownia wood core, alkali-free glass fiber filaments, and unsaturated phthalate resin. Three-point bending and short column axial compression tests were conducted. Then, the stress calculation for the PGWC profile in the bending and axial compression tests was performed using the Timoshenko beam theory and the composite component analysis method to derive the flexural and axial compression rigidity of the profile during the elastic stress stage. The flexural capacity for this type of PGWC profile is 3.3-fold the sum of the flexural capacities of the wood core and the glass-fiber-reinforced polymer (GFRP) shell. The equivalent flexural rigidity is 1.5-fold the summed flexural rigidity of the wood core and GFRP shell. The maximum axial compressive bearing capacity for this type of PGWC profile can reach 1.79-fold the sum of those of the wood core and GFRP shell, and its elastic flexural rigidity is 1.2-fold the sum of their rigidities. These results indicate that in PGWC profiles, GFRP and wood materials have a positive combined effect. This study produced a pultruded composite material product with excellent mechanical performance for application in structures that require a large bearing capacity. PMID:26485431

  7. Experimental Study of the Flexural and Compression Performance of an Innovative Pultruded Glass-Fiber-Reinforced Polymer-Wood Composite Profile.

    Directory of Open Access Journals (Sweden)

    Yujun Qi

    Full Text Available The plate of a pultruded fiber-reinforced polymer or fiber-reinforced plastic (FRP profile produced via a pultrusion process is likely to undergo local buckling and cracking along the fiber direction under an external load. In this study, we constructed a pultruded glass-fiber-reinforced polymer-light wood composite (PGWC profile to explore its mechanical performance. A rectangular cross-sectional PGWC profile was fabricated with a paulownia wood core, alkali-free glass fiber filaments, and unsaturated phthalate resin. Three-point bending and short column axial compression tests were conducted. Then, the stress calculation for the PGWC profile in the bending and axial compression tests was performed using the Timoshenko beam theory and the composite component analysis method to derive the flexural and axial compression rigidity of the profile during the elastic stress stage. The flexural capacity for this type of PGWC profile is 3.3-fold the sum of the flexural capacities of the wood core and the glass-fiber-reinforced polymer (GFRP shell. The equivalent flexural rigidity is 1.5-fold the summed flexural rigidity of the wood core and GFRP shell. The maximum axial compressive bearing capacity for this type of PGWC profile can reach 1.79-fold the sum of those of the wood core and GFRP shell, and its elastic flexural rigidity is 1.2-fold the sum of their rigidities. These results indicate that in PGWC profiles, GFRP and wood materials have a positive combined effect. This study produced a pultruded composite material product with excellent mechanical performance for application in structures that require a large bearing capacity.

  8. Human Immunodeficiency Virus (HIV types Western blot (WB band profiles as potential surrogate markers of HIV disease progression and predictors of vertical transmission in a cohort of infected but antiretroviral therapy naïve pregnant women in Harare, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Chirenje Mike Z

    2011-01-01

    Full Text Available Abstract Background Expensive CD4 count and viral load tests have failed the intended objective of enabling access to HIV therapy in poor resource settings. It is imperative to develop simple, affordable and non-subjective disease monitoring tools to complement clinical staging efforts of inexperienced health personnel currently manning most healthcare centres because of brain drain. Besides accurately predicting HIV infection, sequential appearance of specific bands of WB test offers a window of opportunity to develop a less subjective tool for monitoring disease progression. Methods HIV type characterization was done in a cohort of infected pregnant women at 36 gestational weeks using WB test. Student-t test was used to determine maternal differences in mean full blood counts and viral load of mothers with and those without HIV gag antigen bands. Pearson Chi-square test was used to assess differences in lack of bands appearance with vertical transmission and lymphadenopathy. Results Among the 64 HIV infected pregnant women, 98.4% had pure HIV-1 infection and one woman (1.7% had dual HIV-1/HIV-2 infections. Absence of HIV pol antigen bands was associated with acute infection, p = 0.002. All women with chronic HIV-1 infection had antibody reactivity to both the HIV-1 envelope and polymerase antigens. However, antibody reactivity to gag antigens varied among the women, being 100%, 90%, 70% and 63% for p24, p17, p39 and p55, respectively. Lack of antibody reactivity to gag p39 antigen was associated with disease progression as confirmed by the presence of lymphadenopathy, anemia, higher viral load, p = 0.010, 0.025 and 0.016, respectively. Although not statistically significant, women with p39 band missing were 1.4 times more likely to transmit HIV-1 to their infants. Conclusion Absence of antibody reactivity to pol and gag p39 antigens was associated with acute infection and disease progression, respectively. Apart from its use in HIV disease

  9. Band structures of 121,123I

    International Nuclear Information System (INIS)

    The band structures of 121,123I nuclei have been studied using a version of the particle-rotor-model in which the experimental excitation energies of the neighbouring (A-1) cores can be fed directly as input parameters. The calculations have been carried out with axially symmetric Nilsson potential with both prolate and oblate deformations. The parameters of the model have been chosen from earlier theoretical work and experimental odd-even mass differences. Only the Coriolis attenuation factor has been treated as adjustable parameter. The theoretical band structures are in very good agreement with the available experimental data. (orig.)

  10. Optimization design of hydrogenated amorphous silicon germanium thin film solar cell with graded band gap profile%渐变带隙氢化非晶硅锗薄膜太阳能电池的优化设计

    Institute of Scientific and Technical Information of China (English)

    柯少颖; 王茺; 潘涛; 何鹏; 杨杰; 杨宇

    2014-01-01

    The simulation program AMPS-1D (analysis of microelectronic and photonic structures) employed to simulate and compare the performances of hydrogenated amorphous silicon germanium (a-SiGe : H) thin film solar cell with and without band gap grading at a radiation of AM1.5G (100 mW/cm2) and room temperature by introducing energy band engineering. The simulation results show that the efficiency of the solar cell with band gap grading is 0.477%higher than that without band gap grading due to the higher open circuit voltage (Voc) and better fill factor (F F ). Subsequently, a-SiGe : H thin film solar cells with three different window layers such as hydrogenated amorphous silicon (a-Si : H), hydrogenated amorphous silicon carbide (a-SiC:H) and hydrogenated nanocrystalline silicon (nc-Si:H) are simulated, respectively. The numeric calculation results indicate that the fermi level EF of the a-SiGe:H thin film solar cell crosses the valence band when nc-Si:H window layer is employed in the simulation. This will improve the conductivity and the open circuit voltage of the solar cell. In addition, the electric field at front contact interface is reduced due to the lower contact barrier height. This may be more beneficial to the carrier collection by front contact. On the other hand, thanks to the wider band-gap difference between the window layer and the intrinsic layer, a potential barrier is built at the valence-band p/i interface due to the band offset. This will hinder the hole migration and collection. Thus, an nc-Si:H buffer layer, which can relax the valence-band offset and be more beneficial to the carrier migration and collection, is introduced at p/i interface. Finally, the optimum conversion efficiency of the a-SiGe:H thin film solar cell with graded band gap is achieved to be 9.104%.%利用一维微电子-光电子结构分析软件(AMPS-1D)在AM1.5G (100 mW/cm2)、室温条件下模拟和比较了有、无渐变带隙氢化非晶硅锗(a-SiGe:H)薄膜太阳能

  11. Bandagem reversível do tronco pulmonar IV: análise da hipertrofia aguda do ventrículo direito em modelo experimental de sobrecarga intermitente IV Pulmonary trunk reversible banding: analysis of right ventricle acute hypertrophy in an intermittent loading experimental model

    Directory of Open Access Journals (Sweden)

    Acrisio Sales Valente

    2008-03-01

    Full Text Available OBJETIVO: A bandagem ajustável do tronco pulmonar (TP pode proporcionar treinamento ventricular mais fisiológico para cirurgia de Jatene em dois estágios. Este estudo experimental analisa a hipertrofia aguda (96 horas do ventrículo direito (VD submetido à sobrecarga sistólica intermitente. MÉTODOS: Cinco grupos de sete cabritos jovens foram dispostos conforme o tempo de sobrecarga sistólica do VD (0, 24, 48, 72 e 96 horas. O grupo zero hora funcionou como grupo controle. Avaliações ecocardiográficas e hemodinâmicas foram feitas diariamente. Os animais foram sacrificados para avaliação do conteúdo de água e pesagem das massas cardíacas. RESULTADOS: Houve aumento da espessura do VD a partir de 48 horas de treinamento (pOBJECTIVES: Adjustable pulmonary trunk (PT banding device may induce a more physiologic ventricle retraining for the two-stage Jatene operation. This experimental study evaluates the acute hypertrophy (96 hours of the right ventricle (RV submitted to an intermittent pressure overload. METHODS: Five groups of seven young goats were distributed according to RV intermittent systolic overload duration (0, 24, 48, 72 and 96 hours. The zero-hour group served as a control group. Echocardiographic and hemodynamic evaluations were performed daily. After completing the training program for each group, the animals were sacrificed for water content and cardiac masses evaluation. RESULTS: There was a significant increase in RV free wall thickness starting with the 48-hour group (p<0.05. However, a decreased RV ejection fraction, associated with an important RV dilation and a significant increase in the RV volume to mass ratio was observed at 24-hour training period, when compared to 96-hour period (p=0.003, with subsequent recovery throughout the protocol. A 104.7% increase in RV mass was observed in the 96-hour group, as compared to the control group, with no differences in water content between these two groups. The daily mean

  12. Operational Bright-Band Snow Level Detection Using Doppler Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A method to detect the bright-band snow level from radar reflectivity and Doppler vertical velocity data collection with an atmospheric profiling Doppler radar. The...

  13. One-man band

    OpenAIRE

    Stillman, R.

    2013-01-01

    This website presents practice-based research related to solo simultaneous instrumental performance ('one-man band'). The site was conceived as a creative and widely accessible platform for music and ideas resulting from one-man band activates carried out between 2008 and 2013. Central to this project is an interest in how one-man band technique informs compositional process, including studio production. Through presentation and analysis of the author’s own creative practice, the site exp...

  14. The Novel Microwave Stop-Band Filter

    Directory of Open Access Journals (Sweden)

    R. E. Chernobrovkin

    2008-01-01

    Full Text Available The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave can be excited. The rejection band of the single element is defined by the width, depth, and dielectric filling of the slot. Fifth-order Chebyshev filter utilizing the aforementioned element is also synthesized, manufactured, and tested. The measured and simulated results are in good agreement. The experimental filter prototype exhibits the rejection band 0.86 GHz at the level −40 dB.

  15. Dual-band Omnidirectional Circularly Polarized Antenna

    OpenAIRE

    Narbudowicz, Adam; Bao, Xiulong; Ammann, Max

    2013-01-01

    A dual-band omnidirectional circularly polarized antenna is proposed. The antenna comprises back-to-back microstrip patches fed by a coplanar waveguide. A very low frequency ratio of 1.182 has been achieved, which can be easily tuned by adjusting four lumped capacitors incorporated into the antenna. An analysis of the omnidirectional circular polarization mechanism as well the dual band operation is provided and confirmed by numerical and experimental data. Key parameters to tune the resonant...

  16. Exploring the thermodynamics of a rubber band

    Science.gov (United States)

    Roundy, David; Rogers, Michael

    2013-01-01

    We describe an upper-division experiment in thermal physics where students measure the tension of a rubber band as a function of temperature and length and use a Maxwell relation to find the change in internal energy and entropy for an isothermal stretch. This allows students to experimentally check the predictions of the entropic spring model for elastomers and observe that the entropy does indeed decrease as a rubber band is stretched.

  17. Relativistic Band Calculation and the Optical Properties of Gold

    DEFF Research Database (Denmark)

    Christensen, N Egede; Seraphin, B. O.

    1971-01-01

    of magnitude as the gaps (approximately 1 eV). Various integrated functions, density of states, joint density of states, and energy distributions of joint density of states are derived from the RAPW calculation. These functions are used in an interpretation of photoemission and static reflectance......The energy band structure of gold is calculated by the relativistic augmented-plane-wave (RAPW) method. A nonrelativistic calculation is also presented, and a comparison between this and the RAPW results demonstrates that the shifts and splittings due to relativistic effects are of the same order...... measurements. It is shown that the photoemission results are extremely well described in terms of a model assuming all transitions to be direct whereas a nondirect model fails. The ε2 profile calculated in a crude model assuming constant matrix elements matches well the corresponding experimental results. The...

  18. Collective bands in neutron-rich 104Mo nucleus

    International Nuclear Information System (INIS)

    Levels in the neutron-rich 104Mo nucleus have been investigated by observing prompt γ-rays from the spontaneous fission of 252Cf with the Gamma sphere detector array. The ground-state band, the one-phonon and the two-phonon γ-vibrational bands as well as a quasiparticle band have been confirmed and expanded with spin up to 14ℎ. Other two side bands probably built on new quasiparticle states are identified. The possible configurations for the quasiparticle bands are discussed. Two of the quasiparticle bands show larger moments of inertia and may have pair-free characteristics. The levels of the ground-state band, the one-phonon γ-band and the two-phonon γ-band calculated from a general collective model are in close agreement with the experimental data

  19. The Novel Microwave Stop-Band Filter

    OpenAIRE

    Chernobrovkin, R. E.; Ivanchenko, I. V.; Korolev, A. M.; Popenko, N. A.; K. Yu. Sirenko

    2008-01-01

    The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave) can be excited. The rejection band of the single element is defined by the width, depth, and die...

  20. Asymmetric acoustic transmission in multiple frequency bands

    International Nuclear Information System (INIS)

    We report both experimentally and numerically that the multi-band device of the asymmetric acoustic transmission is realized by placing two periodic gratings with different periods on both sides of two brass plates immersed in water. The asymmetric acoustic transmission can exist in four frequency bands below 1500 kHz, which arises from the interaction between various diffractions from the two gratings and Lamb modes in the brass plates immersed in water. The results indicate that the device has the advantages of multiple band, broader bandwidth, and simpler structure. Our finding should have great potential applications in ultrasonic devices

  1. Electronic band structure of beryllium oxide

    CERN Document Server

    Sashin, V A; Kheifets, A S; Ford, M J

    2003-01-01

    The energy-momentum resolved valence band structure of beryllium oxide has been measured by electron momentum spectroscopy (EMS). Band dispersions, bandwidths and intervalence bandgap, electron momentum density (EMD) and density of occupied states have been extracted from the EMS data. The experimental results are compared with band structure calculations performed within the full potential linear muffin-tin orbital approximation. Our experimental bandwidths of 2.1 +- 0.2 and 4.8 +- 0.3 eV for the oxygen s and p bands, respectively, are in accord with theoretical predictions, as is the s-band EMD after background subtraction. Contrary to the calculations, however, the measured p-band EMD shows large intensity at the GAMMA point. The measured full valence bandwidth of 19.4 +- 0.3 eV is at least 1.4 eV larger than the theory. The experiment also finds a significantly higher value for the p-to-s-band EMD ratio in a broad momentum range compared to the theory.

  2. Exposure measuring techniques for wide band mobile radio-communications

    International Nuclear Information System (INIS)

    The paper illustrates the limits and performances of different experimental monitoring techniques, which are applied to digitally modulated radiofrequency electromagnetic fields used for mobile telecommunications. Different experimental set-ups have been developed, verified and applied for the analysis and characterisation of wide band probes and narrow band measuring procedures. (authors)

  3. Experimental investigation and numerical simulations of void profile development in a vertical cylindrical pipe; Caracterisation experimentale et simulations de l`evolution d`un ecoulement diphasique a bulles ascendant dans une conduite verticale

    Energy Technology Data Exchange (ETDEWEB)

    Grossetete, C.

    1995-12-01

    We present here an experimental investigation and some numerical simulations of void profile development in a vertical cylindrical pipe. This study is motivated by the lack of information dealing with the influence of entrance effects and bubble size evolution upon the multidimensional development of upward bubbly flow in pipe. The axial development of two-phase air-water upward bubbly and bubbly-to-slug transition flows in a vertical pipe is investigated experimentally first. Profiles of liquid mean velocity, liquid axial turbulent intensity, void fraction, bubble frequency, bubble velocity, mean equivalent bubble diameter and volumetric interfacial area are determined along the same test section at three axial locations. It is found that the bubbly-to-slug transition can be deduced from the simultaneous analysis of the different measured profiles. Local analysis of the studied bubbly flows shows that their development does not depend on the shape of the void distribution at the inlet. However, it is found that the bubble size evolution strongly affects the void distribution. Secondly, multidimensional numerical simulations of bubbly flows with very different gas injection modes are made with the help of the tridimensional two-fluid ASTRID code. It is shown that the classical models used to close the transverse momentum equations of the two-fluid model (lift and dispersion forces) do not capture the physical phenomena of bubble migration in pipe flows.

  4. Quality assessment of weather radar wind profiles during bird migration

    NARCIS (Netherlands)

    I. Holleman; H. van Gasteren; W. Bouten

    2008-01-01

    Wind profiles from an operational C-band Doppler radar have been combined with data from a bird tracking radar to assess the wind profile quality during bird migration. The weather radar wind profiles (WRWPs) are retrieved using the well-known volume velocity processing (VVP) technique. The X-band b

  5. Synthesis of standards of the most important markers of Leuckart p-methoxymethamphetamine (PMMA). Examination of the influence of experimental conditions and a drug diluent on SPE/TLC profiling.

    Science.gov (United States)

    Kochana, J; Wilamowski, J; Parczewski, A; Surma, M

    2003-07-01

    The synthesis of characteristic markers of PMMA obtained by Leuckart method was described. The effectiveness of a procedure of SPE/TLC screening profiling of impurities was studied on the basis of selected impurities. The influence of glucose (a drug diluent) on the profile quality was investigated. The intermediate product (characteristic for the Leuckart synthesis) N-formyl-p-methoxymethamphetamine (1) and by-products: N-formyl-p-methoxyamphetamine (2), p-methoxyamphetamine (3), N,N-dimethyl-p-methoxyamphetamine (4), (RS) and (RR/SS) diastereoisomers of bis(1-methyl-2-(4-methoxyphenyl)ethyl)amine (meso-5 and rac-5), (RS) and (RR/SS) diastereoisomers of N-methyl-bis(1-methyl-2-(4-methoxyphenyl)ethyl)amine (meso-6 and rac-6), N-methyl-1,3-bis(4-methoxyphenyl)propane-2-amine (7) were synthesized. The substrate p-methoxyphenylacetone and the impurities 1 and 4 were used in the study of influence of experimental conditions and glucose on the profiling process and results. The experiments were carried out according to a 2(4) factorial design. The proposed criterions of the profile quality are based on matrix presentation of TLC patterns. They take into account the number of spots revealed, differences between R(f) values and intensity of fluorescence, simultaneously. PMID:12850418

  6. Compton profiles and electronic properties of TiB{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Samir, E-mail: sameerbhatt011@gmail.com; Suthar, K. K.; Ahuja, B. L. [Department of Physics, University College of Science ML Sukhadia University, Udaipur-313001 (India); Mishra, Suman K. [CSIR-National Metallurgical Laboratory, Jamshedpur-831007 (India)

    2015-06-24

    In this paper, we report the experimental Compton profile (CP) of TiB{sub 2} using high energy {sup 137}Cs γ-rays Compton spectrometer. To interpret the experimental momentum density, we have calculated the CPs using Hartree-Fock (HF), density functional theory (DFT) and hybridization of DFT and HF within linear combination of atomic orbitals. The theoretical profile with generalized gradient approximation is found to be relatively in better agreement with the experimental profile. A sharp valley in density of states and hence the pseudogap near the Fermi energy is attributed to hybridization of Ti-3d and B-2p states and almost reverse trend of energy bands below and above the Fermi energy.

  7. Efficient operation of a high-power X-band gyroklystron

    OpenAIRE

    Lawson, W.; Calame, J.; Hogan, B.; Latham, P; Read, M; Granatstein, V.; Reiser, M.; Striffler, C.

    1991-01-01

    Experimental studies of amplification in a two-cavity X-band gyroklystron are reported. The system utilizes a thermionic magnetron injection gun at voltages up to 440 kV and currents up to 190 A in 1-μs pulses. Optimum performance is achieved by tapering the magnetic-field profile. Peak powers of 20 MW in the TE01 mode at 9.87 GHz are measured with calibrated crystals and with methanol calorimetry. Resultant efficiencies are in excess of 31% and large-signal gains surpass 26 dB. The experimen...

  8. Identification of the UIR bands

    Science.gov (United States)

    Johnson, Fred M.

    2016-06-01

    Starlight undergoing multiple scattering processes within fluffy grains results in extinction, UV 2175A bump, DIBs and the UIR bands. Spectroscopic lab and DIB data has identified the highly fluorescent molecule Dipyridyl Magnesium Tetrabenzoporphyrin (MgTBP). Reflection and Raman scattering experimental data will be presented which designates this molecule as the primary source for UIR signals. MgTBP sublimes at about 500OC. It is produced via high temperature plasma synthesis within and subsequently ejected from comets which in turn are by-products of solar system-planetary development. Interstellar dust is the left-over refuse which implies prodigious solar system evolution in each galaxy.

  9. Experimental Observation of Large Chern Numbers in Photonic Crystals.

    Science.gov (United States)

    Skirlo, Scott A; Lu, Ling; Igarashi, Yuichi; Yan, Qinghui; Joannopoulos, John; Soljačić, Marin

    2015-12-18

    Despite great interest in the quantum anomalous Hall phase and its analogs, all experimental studies in electronic and bosonic systems have been limited to a Chern number of one. Here, we perform microwave transmission measurements in the bulk and at the edge of ferrimagnetic photonic crystals. Band gaps with large Chern numbers of 2, 3, and 4 are present in the experimental results, which show excellent agreement with theory. We measure the mode profiles and Fourier transform them to produce dispersion relations of the edge modes, whose number and direction match our Chern number calculations. PMID:26722920

  10. Hyperspectral band selection based on parallel particle swarm optimization and impurity function band prioritization schemes

    Science.gov (United States)

    Chang, Yang-Lang; Liu, Jin-Nan; Chen, Yen-Lin; Chang, Wen-Yen; Hsieh, Tung-Ju; Huang, Bormin

    2014-01-01

    In recent years, satellite imaging technologies have resulted in an increased number of bands acquired by hyperspectral sensors, greatly advancing the field of remote sensing. Accordingly, owing to the increasing number of bands, band selection in hyperspectral imagery for dimension reduction is important. This paper presents a framework for band selection in hyperspectral imagery that uses two techniques, referred to as particle swarm optimization (PSO) band selection and the impurity function band prioritization (IFBP) method. With the PSO band selection algorithm, highly correlated bands of hyperspectral imagery can first be grouped into modules to coarsely reduce high-dimensional datasets. Then, these highly correlated band modules are analyzed with the IFBP method to finely select the most important feature bands from the hyperspectral imagery dataset. However, PSO band selection is a time-consuming procedure when the number of hyperspectral bands is very large. Hence, this paper proposes a parallel computing version of PSO, namely parallel PSO (PPSO), using a modern graphics processing unit (GPU) architecture with NVIDIA's compute unified device architecture technology to improve the computational speed of PSO processes. The natural parallelism of the proposed PPSO lies in the fact that each particle can be regarded as an independent agent. Parallel computation benefits the algorithm by providing each agent with a parallel processor. The intrinsic parallel characteristics embedded in PPSO are, therefore, suitable for parallel computation. The effectiveness of the proposed PPSO is evaluated through the use of airborne visible/infrared imaging spectrometer hyperspectral images. The performance of PPSO is validated using the supervised K-nearest neighbor classifier. The experimental results demonstrate that the proposed PPSO/IFBP band selection method can not only improve computational speed, but also offer a satisfactory classification performance.

  11. Atomic structure of amorphous shear bands in boron carbide.

    Science.gov (United States)

    Reddy, K Madhav; Liu, P; Hirata, A; Fujita, T; Chen, M W

    2013-01-01

    Amorphous shear bands are the main deformation and failure mode of super-hard boron carbide subjected to shock loading and high pressures at room temperature. Nevertheless, the formation mechanisms of the amorphous shear bands remain a long-standing scientific curiosity mainly because of the lack of experimental structure information of the disordered shear bands, comprising light elements of carbon and boron only. Here we report the atomic structure of the amorphous shear bands in boron carbide characterized by state-of-the-art aberration-corrected transmission electron microscopy. Distorted icosahedra, displaced from the crystalline matrix, were observed in nano-sized amorphous bands that produce dislocation-like local shear strains. These experimental results provide direct experimental evidence that the formation of amorphous shear bands in boron carbide results from the disassembly of the icosahedra, driven by shear stresses. PMID:24052052

  12. The new real-time measurement capabilities of the profiling TARA radar

    OpenAIRE

    Unal, C.M.H.; Y. Dufournet; Otto, T.; H. W. J. Russchenberg

    2012-01-01

    In the past 10 years, the S-band FM-CW TARA (Transportable Atmospheric RAdar), placed at the Cabauw Experimental Site for Atmospheric Research (CESAR), provided in real-time vertical profiles of the Doppler moments. Classical spectral processing was carried out. The polarimetric and multi-beam measurement capabilities of the radar were not exploited in real-time. It was only possible to acquire raw data for case studies. Based on them, new algorithms were developed using spectral polarimetry ...

  13. Dichroic Filter for Separating W-Band and Ka-Band

    Science.gov (United States)

    Epp, Larry W.; Durden, Stephen L.; Jamnejad, Vahraz; Long, Ezra M.; Sosnowski, John B.; Higuera, Raymond J.; Chen, Jacqueline C.

    2012-01-01

    The proposed Aerosol/Cloud/Ecosystems (ACEs) mission development would advance cloud profiling radar from that used in CloudSat by adding a 35-GHz (Ka-band) channel to the 94-GHz (W-band) channel used in CloudSat. In order to illuminate a single antenna, and use CloudSat-like quasi-optical transmission lines, a spatial diplexer is needed to add the Ka-band channel. A dichroic filter separates Ka-band from W-band by employing advances in electrical discharge machining (EDM) and mode-matching analysis techniques developed and validated for designing dichroics for the Deep Space Network (DSN), to develop a preliminary design that both met the requirements of frequency separation and mechanical strength. First, a mechanical prototype was built using an approximately 102-micron-diameter EDM process, and tolerances of the hole dimensions, wall thickness, radius, and dichroic filter thickness measured. The prototype validated the manufacturing needed to design a dichroic filter for a higher-frequency usage than previously used in the DSN. The initial design was based on a Ka-band design, but thicker walls are required for mechanical rigidity than one obtains by simply scaling the Ka-band dichroic filter. The resulting trade of hole dimensions for mechanical rigidity (wall thickness) required electrical redesign of the hole dimensions. Updates to existing codes in the linear solver decreased the analysis time using mode-matching, enabling the electrical design to be realized quickly. This work is applicable to missions and instruments that seek to extend W-band cloud profiling measurements to other frequencies. By demonstrating a dichroic filter that passes W-band, but reflects a lower frequency, this opens up the development of instruments that both compare to and enhance CloudSat.

  14. Nephron Toxicity Profiling via Untargeted Metabolome Analysis Employing a High Performance Liquid Chromatography-Mass Spectrometry-based Experimental and Computational Pipeline.

    Science.gov (United States)

    Ranninger, Christina; Rurik, Marc; Limonciel, Alice; Ruzek, Silke; Reischl, Roland; Wilmes, Anja; Jennings, Paul; Hewitt, Philip; Dekant, Wolfgang; Kohlbacher, Oliver; Huber, Christian G

    2015-07-31

    Untargeted metabolomics has the potential to improve the predictivity of in vitro toxicity models and therefore may aid the replacement of expensive and laborious animal models. Here we describe a long term repeat dose nephrotoxicity study conducted on the human renal proximal tubular epithelial cell line, RPTEC/TERT1, treated with 10 and 35 μmol·liter(-1) of chloroacetaldehyde, a metabolite of the anti-cancer drug ifosfamide. Our study outlines the establishment of an automated and easy to use untargeted metabolomics workflow for HPLC-high resolution mass spectrometry data. Automated data analysis workflows based on open source software (OpenMS, KNIME) enabled a comprehensive and reproducible analysis of the complex and voluminous metabolomics data produced by the profiling approach. Time- and concentration-dependent responses were clearly evident in the metabolomic profiles. To obtain a more comprehensive picture of the mode of action, transcriptomics and proteomics data were also integrated. For toxicity profiling of chloroacetaldehyde, 428 and 317 metabolite features were detectable in positive and negative modes, respectively, after stringent removal of chemical noise and unstable signals. Changes upon treatment were explored using principal component analysis, and statistically significant differences were identified using linear models for microarray assays. The analysis revealed toxic effects only for the treatment with 35 μmol·liter(-1) for 3 and 14 days. The most regulated metabolites were glutathione and metabolites related to the oxidative stress response of the cells. These findings are corroborated by proteomics and transcriptomics data, which show, among other things, an activation of the Nrf2 and ATF4 pathways. PMID:26055719

  15. EFFECT FOR A SINGLE ROUGHNESS E=5,63mm OF EXPERIMENTAL TO STUDY HYDRAULIC JUMP PROFILE IN A CHANNEL IN U A ROUGH BOTTOM

    Directory of Open Access Journals (Sweden)

    A. Ghomri

    2015-07-01

    Full Text Available This study aims to study the hydraulic jump controlled by threshold, moving in a channel profile 'U' bottomed rough for a single roughness E=5,63mm. Functional relations in dimensionless terms, linking the different characteristics of the projection, showing the effect of roughness of the bottom of the channel are obtained. The hydraulic jump is the primary means used by hydraulic structures to dissipate energy. This hydraulic jump is formed at the sharp transition from a supercritical flow a stream flow.

  16. EFFECT FOR A SINGLE ROUGHNESS E=5,63mm OF EXPERIMENTAL TO STUDY HYDRAULIC JUMP PROFILE IN A CHANNEL IN U A ROUGH BOTTOM

    Directory of Open Access Journals (Sweden)

    A. Ghomri

    2013-06-01

    Full Text Available This study aims to study the hydraulic jump controlled by threshold, moving in a channel profile 'U' bottomed rough for a single roughness E=5,63mm. Functional relations in dimensionless terms, linking the different characteristics of the projection, showing the effect of roughness of the bottom of the channel are obtained. The hydraulic jump is the primary means used by hydraulic structures to dissipate energy. This hydraulic jump is formed at the sharp transition from a supercritical flow a stream flow.

  17. Laparoscopic gastric banding

    Science.gov (United States)

    ... make the band tighter or looser any time after you have this surgery. It may be tightened or ... Having problems eating Not losing enough weight Vomiting after you eat Outlook (Prognosis) The final weight loss with ...

  18. CSF oligoclonal banding - slideshow

    Science.gov (United States)

    ... presentations/100145.htm CSF oligoclonal banding - series—Normal anatomy ... Overview The cerebrospinal fluid (CSF) serves to supply nutrients to the central nervous system (CNS) and collect waste products, as well as ...

  19. The Band Pass Filter

    OpenAIRE

    Christiano, Lawrence J.; Terry J. Fitzgerald

    1999-01-01

    The `ideal' band pass filter can be used to isolate the component of a time series that lies within a particular band of frequencies. However, applying this filter requires a dataset of infinite length. In practice, some sort of approximation is needed. Using projections, we derive approximations that are optimal when the time series representations underlying the raw data have a unit root, or are stationary about a trend. We identify one approximation which, though it is only optimal for one...

  20. Iliotibial band friction syndrome

    OpenAIRE

    Lavine, Ronald

    2010-01-01

    Published articles on iliotibial band friction syndrome have been reviewed. These articles cover the epidemiology, etiology, anatomy, pathology, prevention, and treatment of the condition. This article describes (1) the various etiological models that have been proposed to explain iliotibial band friction syndrome; (2) some of the imaging methods, research studies, and clinical experiences that support or call into question these various models; (3) commonly proposed treatment methods for ili...

  1. Compton profile of scandium oxide

    International Nuclear Information System (INIS)

    In this paper we report the measurement of the Compton profile of polycrystalline scandium oxide using 59.54 keV gamma radiation from a Am241 source. The experimental results are compared with the theoretical Compton profile values calculated based on the linear combination of Gaussian orbital (LCGO) method. The theoretical values from such calculations agree well with the experimental results

  2. Shear banding in mesoscopic dusty plasma liquids

    International Nuclear Information System (INIS)

    We experimentally demonstrate shear banding and construct a microscopic dynamic picture of a sheared 2D mesoscopic dust Coulomb liquid at the kinetic level. Under the topological constraints from the discreteness and finite boundary, the nonlinear threshold-type response of motion to the local stress induced by thermal and external drives leads to shear thinning and the enhanced avalanche-type local topological transitions with stress relaxation in the form of clusters. It causes the formation of the outer shear bands in which the mean shear rate, the velocity fluctuations, and the structural rearrangement rate are all enhanced, and leaves a weakly perturbed center band. The typical size of the cooperative hopping vortex (about three interparticle distance) sets up a common length scale for the widths of the confinement induced layering and the shear band

  3. Determination of band offsets in strained-Si heterolayers

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, C.K.; Samanta, S.K.; Chatterjee, S.; Dalapati, G.K.; Bhattacharya, S.; Armstrong, B.M.; Gamble, H.S.; McCarthy, J.; Perova, T.S.; Moore, R.A

    2004-09-01

    Strained-Si/SiGe/Si structures are of increasing importance for microelectronic applications. A fully relaxed-SiGe buffer layer is required for growing strained-Si for applications towards high performance field effect transistors (FETs) having strained-Si as the channel. Preparation of epitaxial strained-Si layers on relaxed-SiGe (001) heterostructures using low pressure chemical vapor deposition (LPCVD) is reported. Gas source molecular beam epitaxy (GSMBE) grown strained-Si films are used to compare with LPCVD strained-Si films. Characterization of the strained-Si layers has been performed using AFM, TEM and Raman spectroscopy. Conduction and valence band offsets of strained-Si on relaxed-SiGe heterostructures have been extracted from measured capacitance-voltage (C-V) profiling of MOS capacitors fabricated on strained-Si using SiO{sub 2} as the dielectric. Extracted experimental values of the valence and conduction band offsets are in good agreement with theoretical predictions.

  4. Experimental comparison of profiles of acquired small fields with ionization chambers, diodes, radiochromic s and TLD films; Comparacion experimental de perfiles de campos pequenos adquiridos con camaras de ionizacion, diodos, peliculas radiocromicas y TLD

    Energy Technology Data Exchange (ETDEWEB)

    Venencia, D.; Garrigo, E. [Instituto Privado de Radioterapia, Obispo Oro 423, X5000BFI Cordoba (Argentina); Filipuzzi, M. [Instituto Balseiro, Centro Atomico Bariloche, Av. Bustillo 9500, 8400 Bariloche - Rio Negro (Argentina); Germanier, A., E-mail: devenencia@radioncologia-zunino.org [Centro de Excelencia en Productos y Procesos, Santa Maria de Punilla, 5164 Cordoba (Argentina)

    2014-08-15

    The use of radiation small fields, introduced by new techniques, can bring a considerable uncertainty in the precision of the acquired profiles, due to the conditions of lateral electronic non-equilibrium and the perturbations introduced by the detectors (volume effect and alteration of the charged particles flowing) [Das et al., 2007]. The development of new miniature detectors looks to diminish the uncertainty created by the material and the size of the sensitive volume of the dosimeter. For this reason, comparative measurements for three sizes of square field were carried out (20 mm, 10 mm and 5 mm, of side) using a detectors series: 3 ionization chambers (PTW-31003, IBA-CC04, PTW-31016), 2 diodes (PTW-60012, IBA-Sfd), thermoluminescent detectors micro-cubes of 1 mm of edge (TLD-700) and radiochromic s films EBT-3. These last two were used as reference detectors, due to their spatial high resolution and similar performance with Monte Carlo simulations [Francescon et al., 1998]. So much the thermoluminescent detectors as the radiochromic films resolved the profiles in a similar way. Both diodes responded correctly, but the rest of the detectors overestimated the gloom of the fields, which allows conclude that the used TLD (and both diodes) can resolve field sizes correctly, usually utilized in radio-surgery, without producing significant alterations in the acquired data. (author)

  5. Experimental demonstration of a multi-wavelength distributed feedback semiconductor laser array with an equivalent chirped grating profile based on the equivalent chirp technology.

    Science.gov (United States)

    Li, Wangzhe; Zhang, Xia; Yao, Jianping

    2013-08-26

    We report, to the best of our knowledge, the first realization of a multi-wavelength distributed feedback (DFB) semiconductor laser array with an equivalent chirped grating profile based on equivalent chirp technology. All the lasers in the laser array have an identical grating period with an equivalent chirped grating structure, which are realized by nonuniform sampling of the gratings. Different wavelengths are achieved by changing the sampling functions. A multi-wavelength DFB semiconductor laser array is fabricated and the lasing performance is evaluated. The results show that the equivalent chirp technology is an effective solution for monolithic integration of a multi-wavelength laser array with potential for large volume fabrication. PMID:24105542

  6. Synthesis of the first experimental results obtained on the PROFIL-R and M experiments performed in the Phenix fast neutron reactor

    International Nuclear Information System (INIS)

    The PROFIL-R (fast spectrum) and PROFIL-M (moderated spectrum) experiments were performed between 2003 and 2008 in the French fast neutron reactor Phénix. These experiments consisted of the irradiation of pure isotope samples in a well-characterized neutrons flux in order to collect accurate information on the total capture integral cross sections of the principal heavy isotopes and some important fission products in the spectral range of fast reactor. This method can be used for all isotopes transformed by neutron capture into a stable or long-lived nuclide and is based on the measurement of the composition change induced by irradiation. Therefore, accurate and reproducible measurements of isotopic compositions and concentrations of the elements (actinides and fission products) before and after irradiation are required. The major difficulty for the analyses of these actinides and fission products is the low quantity of the initial powder enclosed in steel container (3 to 5 mg) and the very low quantities of products formed (several μg) after irradiation. We present the developments performed during the last few years by laboratories of the French Commission on Atomic Energy and Alternative Energies (CEA) in order to acquire very accurate and precise isotopic and elemental data on selected irradiated powders. Among the necessary developments are the conceptions of systems set in shielded hot-cells to open the steel containers and collect the full amount of powders, and the set-up of specific analytical methods for mass spectrometry measurements in order to obtain isotopic and elemental ratios at uncertainty of few per mil level. A synthesis of the results obtained and first preliminary interpretations will also be presented. (author)

  7. Structure of negative parity yrast bands in odd mass 125-131Ce nuclei

    Indian Academy of Sciences (India)

    Arun Bharti; Suram Singh; S K Khosa

    2010-04-01

    The negative parity yrast bands of neutron-deficient 125-131Ce nuclei are studied by using the projected shell model approach. Energy levels, transition energies and (1)/(2) ratios are calculated and compared with the available experimental data. The calculations reproduce the band-head spins of negative parity yrast bands and indicate the multi-quasiparticle structure for these bands.

  8. Experimental studies of nuclides far from stability with the TRISTAN II fission-product separator at the Brookhaven National Laboratory (Yrast bands; delayed-neutron spectra). Final report, January 1, 1980-November 30, 1982

    International Nuclear Information System (INIS)

    The research program under this contract consisted of two projects; one was the study of yrast bands and the other the study of energy spectra of beta-delayed neutrons. Both utilized the TRISTAN mass separaotr at Brookhaven National Laboratory. The nuclides of interest for the yrast band project were ot produced at TRISTAN during the period of the contract, so effort was limited to planning and to presentation of papers. The neutron project required the design, construction, testing, and calibration of apparatus that is not commercially available. Neutron detectors were later made available onloan. The time-of-flight method was used, beta and neutron signals from scintillators detectors providing start and stop signals. He-3 gas and Li-6 glass scintillators were used for neutrons, plastic for betas. The best timing resolution was 2.7 nsec FWHM; including geometrical contributions,neutron FWHM energy resolution as good as 2.7% at 14 keV was obtained at 50 cm flight path. This is sufficient to deduce the natural line width of the 14 keV resonance in Sr-95. Background neutrons and gamma rays limit the system sensitivity at present, but improvements appear feasible that will permit deduction of leveldensities and in some cases widths of a number of neutron-rich nuclides that are inaccessible to study by any other probe. The data bear on optical models and neutron cross sections for such nuclides

  9. ALMA Band 5 Cartridge Performance

    Science.gov (United States)

    Billade, Bhushan; Lapkin, I.; Nystrom, O.; Sundin, E.; Fredrixon, M.; Finger, R.; Rashid, H.; Desmaris, V.; Meledin, D.; Pavolotsky, A.; Belitsky, Victor

    2010-03-01

    ground plane. The isolated port of the LO coupler is terminated by floating wideband elliptical termination. The mixer employs two SIS junctions with junction area of 3 μm2 each, in twin junction configuration, followed by a quarter wave transformer to couple it to the signal probe. A quarter-wave high impedance line on an extra layer of SiO2 is used to extract the IF by separating from RF. At the conference, we plan to present details of the cartridge design and results of the experimental characterization of the ALMA Band 5 cold cartridge.

  10. Compton profile study and electronic properties of tantalum diboride.

    Science.gov (United States)

    Raykar, Veera; Bhamu, K C; Ahuja, B L

    2013-07-01

    We have reported the first-ever experimental Compton profile (CP) of TaB2 using 20 Ci(137)Cs Compton spectrometer. To compare the experimental data, we have also computed the theoretical CPs using density functional theory (DFT) and hybridization of DFT and Hartree-Fock (HF) within linear combination of the atomic orbitals (LCAO) method. In addition, we have reported energy bands and density of states of TaB2 using LCAO and full potential-linearized augmented plane wave (FP-LAPW) methods. A real space analysis of CP of TaB2 confirms its metallic character which is in tune with the cross-overs of Fermi level by energy bands and Fermi surface topology. A comparison of equal-valence-electron-density (EVED) experimental profiles of isoelectronic TaB2 and NbB2 show more covalent (or less ionic) character of TaB2 than that of NbB2 which is in agreement with available ionicity data. PMID:23518037

  11. POLYCYCLIC AROMATIC HYDROCARBONS AND THE DIFFUSE INTERSTELLAR BANDS: A SURVEY

    International Nuclear Information System (INIS)

    We discuss the proposal of relating the origin of some of the diffuse interstellar absorption bands (DIBs) to neutral polycyclic aromatic hydrocarbons (PAHs) present in translucent interstellar clouds. An assessment of ionized PAHs will be examined in a future report. The spectra of several cold, isolated gas-phase PAHs have been measured in the laboratory under experimental conditions that mimic the interstellar conditions and are compared with an extensive set of astronomical spectra of reddened, early-type stars. This comparison provides-for the first time-accurate upper limits for the abundances of specific PAH molecules along specific lines of sight, something not attainable from IR observations alone. The comparison of these unique laboratory data with high-resolution, high signal-to-noise ratio spectra leads to two major findings: (1) a finding specific to the individual molecules that were probed in this study and, which leads to the clear and unambiguous conclusion that the abundance of these specific neutral PAHs must be very low in the individual translucent interstellar clouds that were probed in this survey (PAH features remain below the level of detection) and, (2) a general finding that neutral PAHs exhibit intrinsic band profiles that are similar to the profile of the narrow DIBs indicating that the carriers of the narrow DIBs must have close molecular structure and characteristics. This study is the first quantitative survey of neutral PAHs in the optical range and it opens the way for unambiguous quantitative searches of PAHs in a variety of interstellar and circumstellar environments.

  12. Tunable band-notched line-defect waveguide in a surface-wave photonic crystal

    CERN Document Server

    Gao, Zhen; Zhang, Youming; Xu, Hongyi; Zhang, Baile

    2016-01-01

    We propose and experimentally demonstrate a tunable band-notched line-defect waveguide in a surface-wave photonic crystal, which consists of a straight line-defect waveguide and side-coupled defect cavities. A tunable narrow stopband can be observed in the broadband transmission spectra. We also demonstrate that both the filtering levels and filtering frequencies of the band-notched line-defect waveguide can be conveniently tuned through changing the total number and the pillar height of the side-coupled defect cavities. The band-notch function is based on the idea that the propagating surface modes with the resonance frequencies of the side-coupled defect cavities will be tightly localized around the defect sites, being filtered from the waveguide output. Transmission spectra measurements and direct near-field profiles imaging are performed at microwave frequencies to verify our idea and design. These results may enable new band-notched devices design and provide routes for the realization of tunable surface...

  13. Banded transformer cores

    Science.gov (United States)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  14. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  15. Experimental validation of concentration profiles in an HCCI engine, modelled by a multi-component kinetic mechanism: Outline for auto-ignition and emission control

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim, E-mail: hatim-machrafi@enscp.f [UPMC Universite Paris 06, Ecole Nationale Superieure de Chimie de Paris, 11, rue de Pierre et Marie Curie, 75005 Paris (France); Universite de Liege, Thermodynamique des Phenomenes Irreversibles, 17, Allee du Six-Aout, 4000 Liege (Belgium)

    2010-10-15

    In order to contribute to the auto-ignition and emission control for Homogeneous Charge Compression Ignition (HCCI), a kinetic multi-component mechanism, containing 62 reactions and 49 species for mixtures of n-heptane, iso-octane and toluene is validated in this work, comparing for the concentration profiles of the fuel, the total hydrocarbons, O{sub 2}, CO{sub 2}, CO, acetaldehyde and iso-butene. These species are sampled during the combustion and quantified. For these measurements an automotive exhaust analyser, a gas chromatograph, coupled to a mass spectrometer and a flame ionisation detector are used, depending on the species to be measured. The fuel, total hydrocarbons, O{sub 2}, CO{sub 2}, iso-butene and acetaldehyde showed a satisfactory quantitative agreement between the mechanism and the experiments. Both the experiments and the modelling results showed the same formation behaviour of the different species. An example is shown of how such a validated mechanism can provide for a set of information of the behaviour of the auto-ignition process and the emission control as a function of engine parameters.

  16. Lipid Profile

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Lipid Profile Share this page: Was this page helpful? Also ... as: Lipid Panel; Coronary Risk Panel Formal name: Lipid Profile Related tests: Cholesterol ; HDL Cholesterol ; LDL Cholesterol ; Triglycerides ; ...

  17. Perfil del peso corporal en la isquemia mesentérica aguda: Estudio experimental en conejos Nueva Zelanda Body weight profile in acute mesenteric ischemia: Experimental study in New-Zealand rabbits

    Directory of Open Access Journals (Sweden)

    J. F. Guijarro Escribano

    2005-12-01

    Full Text Available Introducción y objetivos: Hay pocos trabajos de investigación que relacionen la isquemia mesentérica aguda y el peso corporal en la experimentación animal. Se pretende estudiar, si la pérdida de peso inicial, está relacionada con la magnitud de la agresión provocada por los clampajes de la arteria mesentérica superior durante 30 y 60 minutos, y si la isquemia reperfusión puede dificultar la recuperación ponderal del peso en los animales supervivientes, al final de las 11 semanas del trabajo experimental con conejos Nueva Zelanda, mediante un modelo experimental válido. Material y método: Se distribuyeron 80 animales (conejos en cuatro series de 20: serie I (control, los animales fueron pesados durante 11 semanas; serie II (operación simulada, serie III (isquemia mesentérica 30 minutos y serie IV (isquemia mesentérica 60 minutos. Provocamos la isquemia por pinzamiento de la arteria mesentérica superior. Los animales de las series II, III y IV fueron pesados 24 horas antes del procedimiento quirúrgico y semanalmente en el postoperatorio durante su supervivencia hasta completar 11 semanas. Para el análisis de los pesos, se aplicó un ANOVA enfrentando la variación del peso porcentual en función de la serie. Todos los animales fueron necropsiados para conocer la causa del fallecimiento y las lesiones histológicas de la mucosa intestinal Resultados: La serie control tuvo un incremento lineal del peso hasta el final del período de observación. Las series II, III y IV sufrieron un descenso proceinicial significativo del peso porcentual en la primera semana del postoperatorio, con una recuperación al final del estudio, pero significativamente menor con respecto a la serie control. También se han encontrado diferencias significativas en la recuperación del peso a las 11 semanas entre la serie II y las series III y IV, y entre las series isquémicas entre sí. Conclusiones: Los animales de las series II, III, y IV alcanzaron al

  18. Experimental study on the operating characteristics of an inner preheating transpiring wall reactor for supercritical water oxidation: Temperature profiles and product properties

    International Nuclear Information System (INIS)

    A new process to generate multiple thermal fluids by supercritical water oxidation (SCWO) was proposed to enhance oil recovery. An inner preheating transpiring wall reactor for SCWO was designed and tested to avoid plugging in the preheating section. Hot water (400–600 °C) was used as auxiliary heat source to preheat the feed to the reaction temperature. The effect of different operating parameters on the performance of the inner preheating transpiring wall reactor was investigated, and the optimized operating parameters were determined based on temperature profiles and product properties. The reaction temperature is close to 900 °C at an auxiliary heat source flow of 2.79 kg/h, and the auxiliary heat source flow is determined at 6–14 kg/h to avoid the overheating of the reactor. The useful reaction time is used to quantitatively describe the feed degradation efficiency. The outlet concentration of total organic carbon (TOCout) and CO in the effluent gradually decreases with increasing useful reaction time. The useful reaction time needed for complete oxidation of the feed is 10.5 s for the reactor. - Highlights: • A new process to generate multiple thermal fluids by SCWO was proposed. • An inner preheating transpiring wall reactor for SCWO was designed and tested. • Hot water was used as auxiliary heat source to preheat the feed at room temperature. • Effect of operating parameters on the performance of the reactor was investigated. • The useful reaction time required for complete oxidation of the feed is 10.5 s

  19. MicroRNA profiling of the intestinal tissue of Kazakh sheep after experimental Echinococcus granulosus infection, using a high-throughput approach

    Directory of Open Access Journals (Sweden)

    Jiang Song

    2016-01-01

    Full Text Available Cystic echinococcosis (CE, caused by infection with the larval stage of the cestode Echinococcus granulosus, is a chronic zoonosis, to which sheep are highly susceptible. Previously, we found that Kazakh sheep with different MHC haplotypes differed in CE infection. Sheep with haplotype MHCMvaIbc-SacIIab-Hin1Iab were resistant to CE infection, while their counterparts without this haplotype were not. MicroRNAs (miRNAs, a class of small non-coding RNAs, are key regulators of gene expression at the post-transcriptional level and play essential roles in fundamental biological processes such as development and metabolism. To identify microRNA controlling resistance to CE in the early stage of infection, microRNA profiling was conducted in the intestinal tissue of sheep with resistant and non-resistant MHC haplotypes after peroral infection with E. granulosus eggs. A total of 351 known and 186 novel miRNAs were detected in the resistant group, against 353 known and 129 novel miRNAs in the non-resistant group. Among these miRNAs, 83 known miRNAs were significantly differentially expressed, including 75 up-regulated and 8 down-regulated miRNAs. Among these known microRNAs, miR-21-3p, miR-542-5p, miR-671, miR-134-5p, miR-26b, and miR-27a showed a significantly higher expression in CE-resistant sheep compared to the CE-non-resistant library, with the FC > 3. Functional analysis showed that they were NF-kB pathway-responsive miRNAs, which are involved in the inflammation process. The results suggest that these microRNAs may play important roles in the response of intestinal tissue to E. granulosus.

  20. Amniotic Band Syndrome

    OpenAIRE

    Shetty, Prathvi; Menezes, Leo Theobald; Tauro, Leo Francis; Diddigi, Kumar Arun

    2012-01-01

    Amniotic band syndrome is an uncommon congenital disorder without any genetic or hereditary disposition. It involves fetal entrapment in strands of amniotic tissue and causes an array of deletions and deformations. Primary treatment is plastic and reconstructive surgery after birth with in utero fetal surgery also coming in vogue.

  1. Ka-band waveguide rotary joint

    KAUST Repository

    Yevdokymov, Anatoliy

    2013-04-11

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.

  2. DUAL BAND MONOPOLE ANTENNA DESIGN

    Directory of Open Access Journals (Sweden)

    P. Jithu

    2013-06-01

    Full Text Available The WLAN and Bluetooth applications become popular in mobile devices, integrating GSM and ISM bands operation in one compact antenna, can reduce the size of mobile devices. Recently, lot many investigations are carried out in designing a dual band antennas with operating frequencies in GSM band and in ISM band for mobile devices. Printed monopoles are under this investigation. In this paper, dual-band printed monopoles are presented to operate at GSM band i.e. 900 MHz and ISM band i.e. 2.4 GHz. We intend to observe the antenna characteristics on the network analyzer and verify the theoretical results with the practical ones.

  3. Limitations to band gap tuning in nitride semiconductor alloys

    DEFF Research Database (Denmark)

    Gorczyca, I.; Suski, T.; Christensen, Niels Egede;

    2010-01-01

    Relations between the band gaps of nitride alloys and their lattice parameters are presented and limits to tuning of the fundamental gap in nitride semiconductors are set by combining a large number of experimental data with ab initio theoretical calculations. Large band gap bowings obtained...

  4. Broadband ultrathin low-profile metamaterial microwave absorber

    Science.gov (United States)

    Sood, Deepak; Tripathi, Chandra Charu

    2016-04-01

    In this paper, a single-layer broadband low-profile ultrathin metamaterial microwave absorber is proposed for wide angle of incidence. The proposed absorber provides triple-band absorption under normal incidence of electromagnetic wave with two peaks lying in X-band and one in Ku-band. The unit cell is designed by using parametric optimization in such a way that the three peaks merge together to give broadband absorption. The absorber exhibits full width at half maxima bandwidth (FWHM) of 7.75 GHz from 7.55 to 15.30 GHz for wide angle of incidence up to 60° for both TE and TM polarizations. The mechanism of absorption of the absorber has been analyzed by field and surface current distributions. The proposed absorber has been fabricated and experimentally tested for different angles of incidence and polarization of the incident wave. The absorber is low profile with unit cell dimension of the order of 0.168 λ 0, and it is ultrathin with a thickness of ~ λ 0/17 at the center frequency of 11.43 GHz corresponding to the FWHM absorption bandwidth. This proposed absorber can be used for many potential applications such as stealth technology, cloaking and in antenna systems.

  5. Cardiac markers: profile in rats experimentally infected with Toxocara canis Marcadores cardíacos: perfil em ratos infectados experimentalmente com Toxocara canis

    Directory of Open Access Journals (Sweden)

    Cecília Braga Laposy

    2012-09-01

    Full Text Available The aim of this study was to evaluate the profile of the enzymes creatine kinase (CK, creatine kinase MB (CK-MB and lactate dehydrogenase (LDH in Wistar rats infected with 250 (GI, n = 24 or 1000 (GII, n = 24 Toxocara canis eggs. Animals were evaluated on days 7, 15, 30, 60, 120 and 180 post-infection (DPI. Only the GI rats showed an increase in CK and CK-MB, at 15 and 30 DPI, respectively. Anti-Toxocara spp. antibodies were detected by ELISA in infected animals. Despite of the presence of eosinophilic infiltrate in the heart of three infected animals, none larva was recovered from the organ neither by acid digestion nor by Baermann procedure. Eosinophilia was observed in both groups but there was no significant difference in the eosinophil counts between GI and GII (p = 0.2239. It is possible to consider that cardiac lesion is an eventual finding in murine model for toxocariasis.O objetivo do presente estudo foi avaliar o perfil das enzimas creatinoquinase (CK, creatinoquinase-MB (CK-MB e lactato desidrogenase (LDH em ratos Wistar infectados com 250 (GI, n = 24 ou 1000 (GII, n = 24 ovos de Toxocara canis. Os animais foram avaliados nos dias 7, 15, 30, 60, 120 e 180 pós-infecção (DPI. Observou-se que apenas os animais do GI apresentaram aumento da atividade de CK e CK-MB aos 15 e 30 DPI, respectivamente. Anticorpos anti-T. canis foram detectados por ELISA nos animais infectados. Apesar da presença de infiltrado eosinofílico em três animais infectados, nenhuma larva foi recuperada do coração pela digestão ácida ou pela técnica de Baermann. Eosinofilia foi observada em todos os momentos em GI e GII, sem diferença significativa entre os grupos (p = 0,2239. Pode-se considerar que as lesões cardíacas foram um achado eventual no modelo murino para toxocaríase.

  6. G-protein-coupled receptor affinity prediction based on the use of a profiling dataset: QSAR design, synthesis, and experimental validation.

    Science.gov (United States)

    Rolland, Catherine; Gozalbes, Rafael; Nicolaï, Eric; Paugam, Marie-France; Coussy, Laurent; Barbosa, Frédérique; Horvath, Dragos; Revah, Frédéric

    2005-10-20

    A QSAR model accounting for "average" G-protein-coupled receptor (GPCR) binding was built from a large set of experimental standardized binding data (1939 compounds systematically tested over 40 different GPCRs) and applied to the design of a library of "GPCR-predicted" compounds. Three hundred and sixty of these compounds were randomly selected and tested in 21 GPCR binding assays. Positives were defined by their ability to inhibit by more than 70% the binding of reference compounds at 10 microM. A 5.5-fold enrichment in positives was observed when comparing the "GPCR-predicted" compounds with 600 randomly selected compounds predicted as "non-GPCR" from a general collection. The model was efficient in predicting strongest binders, since enrichment was greater for higher cutoffs. Significant enrichment was also observed for peptidic GPCRs and receptors not included to develop the QSAR model, suggesting the usefulness of the model to design ligands binding with newly identified GPCRs, including orphan ones. PMID:16220973

  7. Head and hand detuning effect study of narrow-band against wide-band mobile phone antennas

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2014-01-01

    Wide-band (WB) and narrow-band (NB) antennas in terms of performance are compared, when interacting with the user’s right head and hand (RHH). The investigations are done through experimental measurements, using standardised head phantom and hand. It is shown that WB antennas detune more than NB ...

  8. Karolinske psychodynamic profile (KAPP)

    DEFF Research Database (Denmark)

    Mathiesen, Birgit Bork; Søgaard, Ulf

    psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil......psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil...

  9. Diffuse interstellar absorption bands

    Institute of Scientific and Technical Information of China (English)

    XIANG FuYuan; LIANG ShunLin; LI AiGen

    2009-01-01

    The diffuse interstellar bands (DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s, the exact nature of DIBs still remains unclear. This article reviews the history of the detec-tions of DIBs in the Milky Way and external galaxies, the major observational characteristics of DIBs, the correlations or anti-correlations among DIBs or between DIBs and other interstellar features (e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise), and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

  10. SURFACE BRIGHTNESS PROFILES OF DWARF GALAXIES. I. PROFILES AND STATISTICS

    International Nuclear Information System (INIS)

    Radial surface brightness profiles of spiral galaxies are classified into three types: (I) single exponential, or the light falls off with one exponential to a break before falling off (II) more steeply, or (III) less steeply. Profile breaks are also found in dwarf disks, but some dwarf Type IIs are flat or increasing out to a break before falling off. Here we re-examine the stellar disk profiles of 141 dwarfs: 96 dwarf irregulars (dIms), 26 Blue Compact Dwarfs (BCDs), and 19 Magellanic-type spirals (Sms). We fit single, double, or even triple exponential profiles in up to 11 passbands: GALEX FUV and NUV, ground-based UBVJHK and Hα, and Spitzer 3.6 and 4.5 μm. We find that more luminous galaxies have brighter centers, larger inner and outer scale lengths, and breaks at larger radii; dwarf trends with MB extend to spirals. However, the V-band break surface brightness is independent of break type, MB , and Hubble type. Dwarf Type II and III profiles fall off similarly beyond the breaks but have different interiors and IIs break ∼twice as far as IIIs. Outer Type II and III scale lengths may have weak trends with wavelength, but pure Type II inner scale lengths clearly decrease from the FUV to visible bands whereas Type III inner scale lengths increase with redder bands. This suggests the influence of different star formation histories on profile type, but nonetheless the break location is approximately the same in all passbands. Dwarfs continue trends between profile and Hubble types such that later-type galaxies have more Type II but fewer Type I and III profiles than early-type spirals. BCDs and Sms are over-represented as Types III and II, respectively, compared to dIms

  11. Game theory based band selection for hyperspectral images

    Science.gov (United States)

    Shi, Aiye; He, Zhenyu; Huang, Fengchen

    2015-12-01

    This paper proposes a new evaluation criterion for band selection for hyperspectral imagery. The combination of information and class separability is used to be as a new evaluation criterion, at the same time, the correlation between bands is used as a constraint condition. In addition, the game theory is introduced into the band selection to coordinate the potential conflict of search the optimal band combination using information and class separability these two evaluation criteria. The experimental results show that the proposed method is effective on AVIRIS hyperspectral data.

  12. Gutzwiller theory of band magnetism in LaOFeAs

    International Nuclear Information System (INIS)

    For the iron pnictide LaOFeAs we investigate multi-band Hubbard models which are assumed to capture the relevant physics. In our calculations, we employ the Gutzwiller variational theory which is a genuine many particle approach. We will present results both on the paramagnetic and antiferromagnetic phases of our model systems. These results show that a five band-model is not adequate to capture the relevant physics in LaOFeAs. However, our results for the eight band-model which includes the arsenic 4p bands reproduce the experimental data, especially the small magnetic moment, for a broad parameter regime.

  13. K-band spectroscopy of deeply embedded, young OB stars

    OpenAIRE

    Bik, A.; Kaper, L.; Hanson, M.M.; Waters, L. B. F. M.

    2006-01-01

    We have obtained high resolution (R = 10,000) K-band spectra of candidate young massive stars deeply embedded in high-mass star-forming regions. These objects were selected from a near-infrared survey of 44 regions of high-mass star-formation (Kaper et al, 2006). In these clusters, 38 OB stars are identified whose K-band spectra are dominated by photospheric emission. In almost all those stars, the K-band spectra are indistinguishable from field stars. However, in some stars the profile of th...

  14. Compact Triple Band Slotted Microstrip Patch Antenna

    Directory of Open Access Journals (Sweden)

    Ram Singh Kushwaha

    2012-03-01

    Full Text Available This paper presents a compact triple band slot microstrip patch antenna for 1.7/2.92 GHz WLAN applications. The radiating element of the proposed antenna consists of Swastika symbol slot operating at 1.8 GHz, 2.09 GHz, and 2.92 GHz bands. The antenna size is very compact (50 mm x 50 mm x 1.6 mm and covers 1.8 GHz to 2.92 GHz and can be used for AMPS, GSM and WLAN applications. The antenna is fed from a single 50 Ω coaxial cable. Using IE3D software package of Zeland, according to the set size, the antenna is simulated. The composite effect of integrating these techniques and by introducing the novel slotted patch offers a low profile, wide bandwidth, high gain and compact antenna element. The computer simulation results show that the antenna can realize wide band characters with each band having good impedance bandwidth (VSWR ≤ 2 for all the three resonant frequencies.

  15. Laboratory Investigation of the Airglow Bands

    Science.gov (United States)

    Drouin, Brian; Yu, Shanshan; Crawford, Timothy J.; Miller, Charles E.; Yee, Jeng-Hwa

    2013-06-01

    We report the first high spectral resolution laboratory measurements of oxygen A-band night glow simulated using a static discharge cell. Our static discharge system reproduces the conditions of the mesospheric oxygen night glow - suggesting O(^1D) + O_2 as the primary source of the emission. Additionally, use of the static cell has enabled us to collect spectra for rare molecular oxygen isotopologues using isotopically enriched samples. The (0,0), (0,1), and (1,1) b-Xvibrational bands were observed with a Bruker 125 HR for all six isotopologues. The (1,2) and (2,2) bands were observed also for the main isotopologue. The frequencies of the observed (0,1) transitions resolved discrepancies in Raman data for (16-17, 17-17, and 17-18), enabling us to improve the vibrational parameterization of the ground electronic state in the global fit of Yu et al. Rotationally resolved intensities were determined for the (0,0), (0,1) and (1,1) bands. The experimental band intensity ratios I(0,0)/I(0,1) = 13.6 and I(0,0)/I(1,1) = 60 are in excellent agreement with the recent mesospheric remote sensing data. S. Yu, C.E. Miller, B.J. Drouin, H.S.P. Müller, J. Chem. Phys. 136, 024304, 2012

  16. The band system of ethane around 7 micron: Frequency analysis of the ν6 band

    Science.gov (United States)

    Moazzen-Ahmadi, N.; Oliaee, J. Norooz

    2016-09-01

    High quality line parameters of the band systems of ethane are required for accurate characterization of spectral features observed in the atmospheres of Jovian planets and their satellites. To date, experimental characterization of the excited vibrational states lying below 1300 cm-1 has been made. This includes the torsional bands around 35 μm, ν9 (820 cm-1), ν3 (990 cm-1), ν12-ν9 (380 cm-1) and ν9+ν4-ν4 (830 cm-1) bands. These earlier high resolution ro-vibrational analyses were made to experimental accuracy. Here, we report a detailed analysis of the weak ν6 band in the 1340-1410 cm-1 region using a spectrum recorded at a resolution of 0.003 cm-1 and temperature of 200 K. The Hamiltonian model included couplings between ν6 and ν9 (in particular with ν9+2ν4 with which it is resonantly coupled) as well as couplings between ν6 and ν8. An excellent fit to within experimental accuracy was obtained. Taking the results of this 5-state fit, together with earlier results on lower lying vibrations, we now have experimental characterization for torsion-vibration states of ethane lying below 1400 cm-1.

  17. Experimental and numerical study of patterns in laryngeal flow

    International Nuclear Information System (INIS)

    Unsteady airflow is investigated in a channel with a geometry approximating that of the human larynx. The laryngeal flow is simulated by solving the Navier-Stokes equations for an incompressible two-dimensional viscous fluid, and visualized using the Schlieren technique in an experimental setup consisting of a rigid replica of the larynx, with and without ventricular bands. This study shows the spontaneous formation of vortex couples in several regions of the laryngeal profile, and at different stages of the evolution of the starting glottal jet.

  18. Photonic-Band-Gap Resonator Gyrotron

    International Nuclear Information System (INIS)

    We report the design and experimental demonstration of a gyrotron oscillator using a photonic-band-gap (PBG) structure to eliminate mode competition in a highly overmoded resonator. The PBG cavity supports a TE041 -like mode at 140GHz and is designed to have no competing modes over a minimum frequency range δω/ω of 30% about the design mode. Experimental operation of a PBG gyrotron at 68kV and 5A produced 25kW of peak power in the design mode. No other modes were observed over the full predicted operating range about the design mode. PBG cavities show great promise for applications in vacuum electron devices in the millimeter- and submillimeter-wave bands

  19. Shear banding in thixotropic and normal emulsions

    International Nuclear Information System (INIS)

    When made to flow, yield stress materials rarely flow homogeneously. This is mostly attributed to the fact that such materials show a transition from a solid- to a liquid-like state when the stress exceeds some critical value: the yield stress. Thus, if the stress is heterogeneous, so is the flow. Here we consider emulsion flows in a cone-plate geometry that, for Newtonian fluids, correspond to a homogeneous stress situation and show that shear banding can also be observed either due to wall slip or to the existence of a critical shear rate. By means of velocity profiles obtained using a confocal laser scanning microscope combined with a rheometer we conclude that the last type of shear banding occurs only in thixotropic yield stress materials.

  20. Shear banding in thixotropic and normal emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Jose; Bonn, Daniel [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098XH Amsterdam (Netherlands); Shahidzadeh-Bonn, Noushine [Institut Navier, ENPC-IFSTTAR-CNRS, 6 et 8 Avenue Blaise-Pascal, F-77455 Champs-sur-Marne Cedex 2 (France)

    2011-07-20

    When made to flow, yield stress materials rarely flow homogeneously. This is mostly attributed to the fact that such materials show a transition from a solid- to a liquid-like state when the stress exceeds some critical value: the yield stress. Thus, if the stress is heterogeneous, so is the flow. Here we consider emulsion flows in a cone-plate geometry that, for Newtonian fluids, correspond to a homogeneous stress situation and show that shear banding can also be observed either due to wall slip or to the existence of a critical shear rate. By means of velocity profiles obtained using a confocal laser scanning microscope combined with a rheometer we conclude that the last type of shear banding occurs only in thixotropic yield stress materials.

  1. Elucidating the stop bands of structurally colored systems through recursion

    CERN Document Server

    Amir, Ariel

    2012-01-01

    Interference phenomena are the source of some of the spectacular colors of animals and plants in nature. In some of these systems, the physical structure consists of an ordered array of layers with alternating high and low refractive indices. This periodicity leads to an optical band structure that is analogous to the electronic band structure encountered in semiconductor physics; namely, specific bands of wavelengths (the stop bands) are perfectly reflected. Here, we present a minimal model for optical band structure in a periodic multilayer and solve it using recursion relations. We present experimental data for various beetles, whose optical structure resembles the proposed model. The stop bands emerge in the limit of an infinite number of layers by finding the fixed point of the recursive relations. In order for these to converge, an infinitesimal amount of absorption needs to be present, reminiscent of the regularization procedures commonly used in physics calculations. Thus, using only the phenomenon of...

  2. Lifetimes of an excited superdeformed band in {sup 192}Hg

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Blumenthal, D.; Carpenter, M.P. [and others

    1995-08-01

    An excited superdeformed band was identified in {sup 192}Hg and the lifetimes of its levels measured with the Doppler-shift attenuation method from data taken with the Eurogam spectrometer. The band is proposed to be based on the two-quasineutron (v[642]3/2 [512]5/2) configuration, which after a band crossing, becomes the (v[642]3/2 [752]5/2) configuration. The transition quadrupole moment Q{sub t} of the excited band is the same as that of the yrast SD band, within experimental errors. This suggests that the deformation of the SD minimum is robust with respect to quasiparticle excitation, despite the occupation of the deformation-driving v[752]5/2 level (from the j{sub 15/2} shell) after the band crossing.

  3. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  4. Quality assessment of weather radar wind profiles during bird migration

    OpenAIRE

    Holleman, I.; Gasteren, van, H.; W. Bouten

    2008-01-01

    Wind profiles from an operational C-band Doppler radar have been combined with data from a bird tracking radar to assess the wind profile quality during bird migration. The weather radar wind profiles (WRWPs) are retrieved using the well-known volume velocity processing (VVP) technique. The X-band bird radar performed range-height scans perpendicular to the main migration direction and bird densities were deduced by counting and normalizing the observed echoes. It is found that the radial vel...

  5. Resolving the forbidden band of SF6.

    Science.gov (United States)

    Boudon, V; Manceron, L; Kwabia Tchana, F; Loëte, M; Lago, L; Roy, P

    2014-01-28

    Sulfur hexafluoride is an important molecule for modeling thermophysical and polarizability properties. It is also a potent greenhouse gas of anthropogenic origin, whose concentration in the atmosphere, although very low is increasing rapidly; its global warming power is mostly conferred by its strong infrared absorption in the ν3 S-F stretching region near 948 cm(-1). This heavy species, however, features many hot bands at room temperature (at which only 31% of the molecules lie in the ground vibrational state), especially those originating from the lowest, v6 = 1 vibrational state. Unfortunately, the ν6 band itself (near 347 cm(-1)), in the first approximation, is both infrared- and Raman-inactive, and no reliable spectroscopic information could be obtained up to now and this has precluded a correct modeling of the hot bands. It has been suggested theoretically and experimentally that this band might be slightly activated through Coriolis interaction with infrared-active fundamentals and appears in high pressure measurements as a very faint, unresolved band. Using a new cryogenic multipass cell with 93 m optical path length and regulated at 163 ± 2 K temperature, coupled to synchrotron radiation and a high resolution interferometer, the spectrum of the ν6 far-infrared region has been recorded. Low temperature was used to avoid the presence of hot bands. We are thus able to confirm that the small feature in this region, previously viewed at low-resolution, is indeed ν6. The fully resolved spectrum has been analyzed, thanks to the XTDS software package. The band appears to be activated by faint Coriolis interactions with the strong ν3 and ν4 fundamental bands, resulting in the appearance of a small first-order dipole moment term, inducing unusual selection rules. The band center (ν6 = 347.736707(35) cm(-1)) and rovibrational parameters are now accurately determined for the v6 = 1 level. The ν6 perturbation-induced dipole moment is estimated to be 33 ± 3

  6. Shuttle Ku-band and S-band communications implementation study

    Science.gov (United States)

    Dodds, J. G.; Huth, G. K.; Nilsen, P. W.; Polydoros, A.; Simon, M. K.; Weber, C. L.

    1980-05-01

    Various aspects of the shuttle orbiter S-band network communication system, the S-band payload communication system, and the Ku-band communication system are considered. A method is proposed for obtaining more accurate S-band antenna patterns of the actual shuttle orbiter vehicle during flight because the preliminary antenna patterns using mock-ups are not realistic that they do not include the effects of additional appendages such as wings and tail structures. The Ku-band communication system is discussed especially the TDRS antenna pointing accuracy with respect to the orbiter and the modifications required and resulting performance characteristics of the convolutionally encoded high data rate return link to maintain bit synchronizer lock on the ground. The TDRS user constraints on data bit clock jitter and data asymmetry on unbalanced QPSK with noisy phase references are included. The S-band payload communication system study is outlined including the advantages and experimental results of a peak regulator design built and evaluated by Axiomatrix for the bent-pipe link versus the existing RMS-type regulator. The nominal sweep rate for the deep-space transponder of 250 Hz/s, and effects of phase noise on the performance of a communication system are analyzed.

  7. Bandcrossing of magnetic rotation bands in 137Pr

    International Nuclear Information System (INIS)

    The odd mass nucleus 137Pr has been studied to high spins in order to investigate the magnetic rotation phenomenon in mass 130 region using the 122Sn(19F,4n)137Pr reaction at a beam energy of 80 MeV. A known ΔI=1 band has been extended to Jπ=47/2- with the addition of three new transitions. Directional Correlation of Oriented Nuclei (DCO) ratios and linear polarization measurements have been performed to assign the multipolarities of gamma transitions and the spins and parities of the energy levels in this band, now established as the M1 band. The combination of M1 transitions along with cross over E2 transitions have been observed in this band for the first time. The experimentally deduced B(M1)/B(E2) ratios show a decrease with increasing spin after band-crossing suggesting magnetic rotation. TAC calculations for the 3qp: πh11/2 x ν(h11/2)-2 configuration reproduce the experimental observations in the lower spin part of the ΔI=1 band and the 5qp: πh11/2(g7/2)2 x ν(h11/2)-2 configuration reproduces the ΔI=1 band at higher spins; the crossing of the bands based on the two configuration leads to a back-bending also. Theoretical calculations also support a magnetic rotation nature for both the configurations

  8. Shape Coexistence and Band Termination in the Doubly Magic Nucleus 40Ca

    Institute of Scientific and Technical Information of China (English)

    DONGBao-guo; GUOHong-chao

    2003-01-01

    Shape coexistence and band structure near yrast line of the Z=N doubly magic nucleus 40Ca have been investigated by the configuration-dependent cranked Nilsson-Strutinsky approach and the calculated bands show good agreement with experimental observations at high spin. The observed normal deformed and superdeformed bands are explained theoretically and the terminating states are confirmed by the calculations.

  9. Rietveld analysis and electronic bands structure on Tc superconductors systems

    International Nuclear Information System (INIS)

    A procedure for simultaneous refinement of structural and micro-structural disorder parameters for polycrystalline YBa2Cu3O7-x system is proposed. It is based on Rietveld method combined with Fourier analysis for broadened peaks Another purpose of this paper consists in electronic structure determination studied by using the self-consistent Tight Binding Linear Muffin-Tin Orbital Atomic Spheres Approximation TB-LMTO-ASA methods. The Rietveld method uses an analytical function that describes the profiles, usually pseudo-Voigt (pV) or Pearson VII (PVII). The parameters of the analytical profiles describe its amplitude, position and peak shape. The full width at half maximum (FWHM) is supposed to vary with the diffraction angle in agreement with the Caglioti, Paoletti and Ricci's relationship. The best structural parameters are determined in the least squares sense by the minimisation a classical residual using the Marquardt method. In this case, the peak profiles were modelled by the pseudo-Voigt function corrected by the instrumental asymmetry. The physical information obtained are: scale factor, lattice parameters, atomic position and displacements, atomic occupation numbers, temperature factor (isotropy or anisotropy), preferred orientation parameter, crystalline size and micro-strain along different crystallographic directions, distributions of crystallite size and micro-strain functions. This procedure was implemented on computer code and it has a friendly graphical interface based on pull down menus technique. From the experimental point of view the X-ray diffraction data were collected using a horizontal powder diffractometer in the Bragg-Brentano (BB) geometry with a Ni filtered CuKα, λ = 1.54178 A, at room temperature using a DRON 2 set-up. The diffraction profiles were measured with a proportional gas detector, a single channel pulse-height discrimination and a standard associated counting circuit. The electronic band calculations are based on the TB

  10. Signal Processing and Data Acquisition for Wind Profiler Using Labview

    Directory of Open Access Journals (Sweden)

    Priyank V. Gandhi

    2014-04-01

    Full Text Available This paper presents the design of Wind Profiler using LabVIEW. Wind speed is a useful weather parameter to monitor and record for many applications like shipping, aviation, meteorology, construction etc. Wind observations are crucial importance for general (operational aviation meteorology, and numerical weather prediction. Wind profiler radars are vertically directed pulsed Doppler radars capable of analyzing the back-scattered signals to determine the velocity of air along the beams. Steering the beams typically 15° from zenith, the horizontal and vertical components of the air moment can be obtained. The extraction of zeroth, first and second moments is the key reason for doing all the signal processing. For measurements above 20 km, the 50 MHz frequency band can be used. The paper discusses the issues such as the principle of wind profiler radar, how wind profilers estimate the horizontal wind as a function of altitude in "clear air‟, Doppler Beam Swinging (DBS technique for Wind velocity measurement. Moment calculation and Signal processing of recoded experimental data is performed by LabVIEW code developed in my project.

  11. Scattering from bare soils: C-band multipolarization scatterometer measurements

    Science.gov (United States)

    Casarano, Domenico; Buono, G.; Paparella, F.; Posa, Francesco; Sabatelli, Vincenzo

    1998-11-01

    Multi-angle, multi-polarization C-band backscattering measurements were performed over selected bare soil areas. To perform these measurements, an FM-CW radar has been designed and assembled. This device has the capability of resolving independent samples within the antenna footprint area, thus allowing range discrimination and improving the signal statistics. Two areas with different degrees of roughness and dielectric constants were selected and set up. Co-polarized backscattering coefficients were measured for incidence angles between 23 degrees and 60 degrees. To perform a model analysis of the backscattering properties, 'ground truth' data, including surface roughness profiles and soil moisture values (directly related to dielectric constant) were also collected. The 'classical' parameters, used to describe surface roughness, showed a wide spreading. This evidence and the data resulting from ground truth campaigns over many European test sites suggested an alternative description of surface roughness, based on the self-similarity (fractal) properties. The surfaces have therefore been described as fBm (Fractional Brownian Motion) processes, and their backscattering response has been theoretically modeled by a numerical simulation (in 3-D in order to also take into account anisotropy effects) in Kirchhoff approximation. The experimental data have been analyzed with both asymptotic models (IEM) considering a classical statistical description, and with the numerical simulation applied to fBm surfaces.

  12. Profiling cancer

    DEFF Research Database (Denmark)

    Ciro, Marco; Bracken, Adrian P; Helin, Kristian

    2003-01-01

    In the past couple of years, several very exciting studies have demonstrated the enormous power of gene-expression profiling for cancer classification and prediction of patient survival. In addition to promising a more accurate classification of cancer and therefore better treatment of patients......, gene-expression profiling can result in the identification of novel potential targets for cancer therapy and a better understanding of the molecular mechanisms leading to cancer....

  13. Investigation of PLC band nucleation in AA5754

    International Nuclear Information System (INIS)

    Highlights: ► Simultaneous propagation of bands in transverse and longitudinal directions. ► PLC band nucleation at the back front of Lüders bands. ► Characteristic time of critical strain decreases with strain rate. ► Simultaneous existence of two type-B bands at specimen shoulder. - Abstract: The purpose of the present work is the experimental investigation of the nucleation of PLC deformation bands in the aluminium alloy AA5754. The PLC bands are investigated using both mechanical methods and infrared (IR) thermography. The latter employs a high-speed IR camera which captures local changes of radiated power resulting from mechanical dissipation and heating due to the nucleation of PLC bands. The resulting IR images are used to determine spatio-temporal power field variations via image subtraction. Furthermore, band trajectories obtained from the IR images are used to study possible correlations between the spatio-temporal evolution of stress and radiated power in the specimens and PLC band development.

  14. Compton profiles and electronic structure of monoclinic zinc and cadmium tungstates

    Science.gov (United States)

    Meena, B. S.; Heda, N. L.; Mund, H. S.; Ahuja, B. L.

    2015-12-01

    We report the first ever Compton scattering study of ZnWO4 and CdWO4 using 20 Ci 137Cs Compton spectrometer at momentum resolution of 0.34 a.u. To compare the experimental Compton profiles, we have also deduced the momentum densities using density functional theory (DFT) within linear combination of atomic orbitals (LCAO) methods. It is seen that the experimental Compton profiles of both the tungstates give a better agreement with LCAO-DFT calculations within generalized gradient approximation (GGA) employing Perdew-Becke-Ernzerhof (PBE) exchange and correlation energies than other approximations included in the present work. Further, energy bands, density of states (DOS) and band gaps have also been calculated using LCAO-DFT-GGA-PBE scheme and full potential linearized augmented plane wave method. Both the computational schemes show a semiconducting nature of both the tungstates, with a direct band gap at Y point of Brillouin zone. Further, a relative nature of bonding on equal-valence-electron-density scale shows more covalent character in ZnWO4 than CdWO4 which reconciles with the conclusions drawn using integrated DOS and Mulliken's population data.

  15. Proceedings of wide band gap semiconductors

    International Nuclear Information System (INIS)

    This book contains the proceedings of wide band gap semiconductors. Wide band gap semiconductors are under intense study because of their potential applications in photonic devices in the visible and ultraviolet part of the electromagnetic spectrum, and devices for high temperature, high frequency and high power electronics. Additionally, due to their unique mechanical, thermal, optical, chemical, and electronic properties many wide band gap semiconductors are anticipated to find applications in thermoelectric, electrooptic, piezoelectric and acoustooptic devices as well as protective coatings, hard coatings and heat sinks. Material systems covered in this symposium include diamond, II-VI compounds, III-V nitrides, silicon carbide, boron compounds, amorphous and microcrystalline semiconductors, chalcopyrites, oxides and halides. The various papers addressed recent experimental and theoretical developments. They covered issues related to crystal growth (bulk and thin films), structure and microstructure, defects, doping, optoelectronic properties and device applications. A theoretical session was dedicated to identifying common themes in the heteroepitaxy and the role of defects in doping, compensation and phase stability of this unique class of materials. Important experimental milestones included the demonstrations of bright blue injection luminescence at room temperatures from junctions based on III-V nitrides and a similar result from multiple quantum wells in a ZnSe double heterojunction at liquid nitrogen temperatures

  16. Multitude multicolor chromosome banding (mMCB) - a comprehensive one-step multicolor FISH banding method.

    Science.gov (United States)

    Weise, A; Heller, A; Starke, H; Mrasek, K; Kuechler, A; Pool-Zobel, B L; Claussen, U; Liehr, T

    2003-01-01

    Multicolor chromosome banding (MCB) using one single chromosome-specific MCB probe set per experiment was previously reported as powerful tool in molecular cytogenetics for the characterization of all kinds of human marker chromosomes. However, a quick analysis of karyotypes with highly complex chromosomal changes was hampered by the problem that up to 24 MCB experiments were necessary for a comprehensive karyotype description. To overcome that limitation the 138 available region-specific microdissection-derived libraries for all human chromosomes were combined to one single probe set, called multitude MCB (mMCB). A typical fluorescence banding pattern along the human karyotype is produced, which can be evaluated either by transforming these profiles into chromosome region-specific pseudo-colors or more reliably by studying the fluorescence profiles. The mMCB probe set has been applied on chromosomes of normal male and female probands, two primary myelodysplastic syndromes and two solid tumor cell lines. Additionally, a cell line of Gorilla gorilla (GGO) studied previously by single chromosome-specific MCB was reevaluated by the mMCB method. All results were in concordance with those obtained in parallel or by other cytogenetic and molecular cytogenetic approaches indicating that mMCB is a powerful multicolor FISH banding tool for fast characterization of complex karyotypes. PMID:15004461

  17. Flat Bands Under Correlated Perturbations

    OpenAIRE

    Bodyfelt, Joshua D.; Leykam, Daniel; Danieli, Carlo; Yu, Xiaoquan; Flach, Sergej

    2014-01-01

    Flat band networks are characterized by coexistence of dispersive and flat bands. Flat bands (FB) are generated by compact localized eigenstates (CLS) with local network symmetries, based on destructive interference. Correlated disorder and quasiperiodic potentials hybridize CLS without additional renormalization, yet with surprising consequencies: (i) states are expelled from the FB energy $E_{FB}$, (ii) the localization length of eigenstates vanishes as $\\xi \\sim 1 / \\ln (E- E_{FB})$, (iii)...

  18. Cluster banding heat source model

    Institute of Scientific and Technical Information of China (English)

    Zhang Liguo; Ji Shude; Yang Jianguo; Fang Hongyuan; Li Yafan

    2006-01-01

    Concept of cluster banding heat source model is put forward for the problem of overmany increment steps in the process of numerical simulation of large welding structures, and expression of cluster banding heat source model is deduced based on energy conservation law.Because the expression of cluster banding heat source model deduced is suitable for random weld width, quantitative analysis of welding stress field for large welding structures which have regular welds can be made quickly.

  19. Development of Wide Band Feeds

    Science.gov (United States)

    Ujihara, H.; Ichikawa, R.

    2012-12-01

    Wide Band feeds are being developed at NICT, NAOJ, and some universities in Japan for VLBI2010, SKA, and MARBLE. SKA, the Square Kilometre Array, will comprise thousands of radio telescopes with square kilometer aperture size for radio astronomy. MARBLE consists of small portable VLBI stations developed at NICT and GSI in Japan. They all need wide band feeds with a greater than 1:10 frequency ratio. Thus we have been studying wide band feeds with dual linear polarization for these applications.

  20. Efficient video cutout based on adaptive multilevel banded method

    Institute of Scientific and Technical Information of China (English)

    CHEN MinGang; SUI BoCong; GAO Yan; MA LiZhuang

    2012-01-01

    Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout results.In this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video cutout.In our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph cuts.We construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during propagation. Experimental results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

  1. Band mixing effects in mean field theories

    International Nuclear Information System (INIS)

    The 1/N expansion method, which is an angular momentum projected mean field theory, is used to investigate the nature of electromagnetic transitions in the interacting boson model (IBM). Conversely, comparison with the exact IBM results sheds light on the range of validity of the mean field theory. It is shown that the projected mean field results for the E2 transitions among the ground, β and γ bands are incomplete for the spin dependent terms and it is essential to include band mixing effect for a correct (Mikhailov) analysis of E2 data. The algebraic expressions derived are general and will be useful in the analysis of experimental data in terms of both the sd and sdg boson models. 17 refs., 7 figs., 8 tabs

  2. Accurate valence band width of diamond

    International Nuclear Information System (INIS)

    An accurate width is determined for the valence band of diamond by imaging photoelectron momentum distributions for a variety of initial- and final-state energies. The experimental result of 23.0±0.2 eV2 agrees well with first-principles quasiparticle calculations (23.0 and 22.88 eV) and significantly exceeds the local-density-functional width, 21.5±0.2 eV2. This difference quantifies effects of creating an excited hole state (with associated many-body effects) in a band measurement vs studying ground-state properties treated by local-density-functional calculations. copyright 1997 The American Physical Society

  3. Garage Band or GarageBand[R]? Remixing Musical Futures

    Science.gov (United States)

    Vakeva, Lauri

    2010-01-01

    In this paper, I suggest that it is perhaps time to consider the pedagogy of popular music in more extensive terms than conventional rock band practices have to offer. One direction in which this might lead is the expansion of the informal pedagogy based on a "garage band" model to encompass various modes of digital artistry wherever this artistry…

  4. Are Defect Profile Similarity Criteria Different Than Velocity Profile Similarity Criteria for the Turbulent Boundary Layer?

    OpenAIRE

    Weyburne, David

    2015-01-01

    The use of the defect profile instead of the experimentally observed velocity profile for the search for similarity parameters has become firmly imbedded in the turbulent boundary layer literature. However, a search of the literature reveals that there are no theoretical reasons for this defect profile preference over the more traditional velocity profile. In the report herein, we use the flow governing equation approach to develop similarity criteria for the two profiles. Results show that t...

  5. Simultaneous confidence bands in linear regression analysis

    OpenAIRE

    Ah-Kine, Pascal Soon Shien

    2010-01-01

    A simultaneous confidence band provides useful information on the plausible range of an unknown regression model. For a simple linear regression model, the most frequently quoted bands in the statistical literature include the two-segment band, the three-segment band and the hyperbolic band, and for a multiple linear regression model, the most com- mon bands in the statistical literature include the hyperbolic band and the constant width band. The optimality criteria for confid...

  6. Wide HI profile galaxies

    CERN Document Server

    Brosch, Noah; Zitrin, Adi

    2011-01-01

    We investigate the nature of objects in a complete sample of 28 galaxies selected from the first sky area fully covered by ALFALFA, being well-detected and having HI profiles wider than 550 km/s. The selection does not use brightness, morphology, or any other property derived from optical or other spectral bands. We investigate the degree of isolation, the morphology, and other properties gathered or derived from open data bases and show that some objects have wide HI profiles probably because they are disturbed or are interacting, or might be confused in the ALFALFA beam. We identify a sub-sample of 14 galaxies lacking immediate interacting neighbours and showing regular, symmetric, two-horned HI profiles that we propose as candidate high-mass disk systems (CHMDs). We measure the net-Halpha emission from the CHMDs and combine this with public multispectral data to model the global star formation (SF) properties of each galaxy. The Halpha observations show SFRs not higher than a few solar masses per year. Sim...

  7. Intermediate Band Solar Cell with Extreme Broadband Spectrum Quantum Efficiency

    OpenAIRE

    2015-01-01

    We report, for the first time, about an intermediate band solar cell implemented with InAs/AlGaAs quantum dots whose photoresponse expands from 250 to ~ 6000  nm. To our knowledge, this is the broadest quantum efficiency reported to date for a solar cell and demonstrates that the intermediate band solar cell is capable of producing photocurrent when illuminated with photons whose energy equals the energy of the lowest band gap. We show experimental evidence indicating that this result is in a...

  8. Observation of localized flat-band modes in a one-dimensional photonic rhombic lattice

    CERN Document Server

    Mukherjee, Sebabrata

    2015-01-01

    We experimentally demonstrate the photonic realization of a dispersionless flat-band in a one-dimensional photonic rhombic lattice fabricated by ultrafast laser inscription. In the nearest neighbor tight binding approximation the lattice supports two dispersive and a non-dispersive (flat) band. We experimentally excite a superposition of flat-band eigen modes at the input of the photonic lattice and show the diffractionless propagation of the input modes due to their infinite effective mass.

  9. Early stage breast cancer detection by means of time-domain ultra-wide band sensing

    International Nuclear Information System (INIS)

    The interest in the use of ultra-wide band (UWB) impulses for medical imaging, particularly early stage breast cancer detection, is driven by safety advantage, super resolution capability, significant dielectric contrast between tumours and their surrounding tissues, patient convenience and low operating costs. However, inversion algorithms leading to recovery of the dielectric profile are complex in their nature, and vulnerable to noisy experimental conditions and environment. In this paper, we present a simplified yet robust gradient-based iterative image reconstruction technique to solve the nonlinear inverse scattering problem. The calculation is based on the Polak–Ribière's approach while the Broyden's formula is used to update the gradient in an iterative scheme. To validate this approach, both numerical and experimental results are presented. Animal derived biological targets in the form of chicken skin, beef and salted butter are used to construct an experimental breast phantom, while vegetable oil is used as a background media. UWB transceivers in the form of biconical antennas contour the breast forming a full view scanning geometry at a frequency range of 0–5 GHz. Results indicate the feasibility of experimental detection of millimetre scaled targets

  10. Early stage breast cancer detection by means of time-domain ultra-wide band sensing

    Science.gov (United States)

    Zanoon, T. F.; Abdullah, M. Z.

    2011-11-01

    The interest in the use of ultra-wide band (UWB) impulses for medical imaging, particularly early stage breast cancer detection, is driven by safety advantage, super resolution capability, significant dielectric contrast between tumours and their surrounding tissues, patient convenience and low operating costs. However, inversion algorithms leading to recovery of the dielectric profile are complex in their nature, and vulnerable to noisy experimental conditions and environment. In this paper, we present a simplified yet robust gradient-based iterative image reconstruction technique to solve the nonlinear inverse scattering problem. The calculation is based on the Polak-Ribière's approach while the Broyden's formula is used to update the gradient in an iterative scheme. To validate this approach, both numerical and experimental results are presented. Animal derived biological targets in the form of chicken skin, beef and salted butter are used to construct an experimental breast phantom, while vegetable oil is used as a background media. UWB transceivers in the form of biconical antennas contour the breast forming a full view scanning geometry at a frequency range of 0-5 GHz. Results indicate the feasibility of experimental detection of millimetre scaled targets.

  11. Motion Analysis of Fiber Band in Compact Field of Compact Spinning

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The technological process of compact spinning and the compact procedure of fiber band in compact field are briefly illustrated. The motions of fiber band in compact field are discussed theoretically from which tilting angle of suction slot in profile tube, additional twists created by fiber band's rotating around its own axis and ultimate twists in compact yarn are deduced accordingly. The existence of additional twists is also verified through experiments.

  12. Profile video

    Science.gov (United States)

    Voglewede, Paul E.; Zampieron, Jeffrey

    2009-05-01

    For unattended persistent surveillance there is a need for a system which provides the following information: target classification, target quantity estimate, cargo presence and characterization, direction of travel, and action. Over highly bandwidth restricted links, such as Iridium, SATCOM or HF, the data rates of common techniques are too high, even after aggressive compression, to deliver the required intelligence in a timely, low power manner. We propose the following solution to this data rate problem: Profile Video. Profile video is a new technique which provides all of the required information in a very low data-rate package.

  13. The Moral Ends of Band

    Science.gov (United States)

    Allsup, Randall Everett

    2012-01-01

    This article provides a theoretical framework through which to reimagine and revitalize contemporary music education practices, using the large ensemble paradigm called "band" as the primary unit of analysis. Literature suggests that band places too much emphasis on teacher control and external measures of validation. Critics propose replacing…

  14. Synthesis and design of waveguide band-stop filters without out-of-band spurious responses for plasma diagnosis

    International Nuclear Information System (INIS)

    Highlights: ► A rigorous systematic design process based on circuit synthesis is proposed for band-stop filters. ► The new compact E-plane waveguide structure reduces drastically the unwanted resonances in a very large pass band. ► The manufacturing process together with the computation effort is significantly reduced. ► Experimental results validate the state-of-art electrical responses. - Abstract: Band-stop or notch filters play a crucial role in plasma diagnosis systems to protect receivers from the stray radiation. In this work, a rigorous design process based on circuit synthesis in addition to an extremely compact E-plane waveguide structure is proposed for this kind of filters. On the one hand, the transfer function verifying the rejection specification is analytically obtained, fixing the minimum number of required cavities. On the other hand, a coupling structure that reduces drastically the unwanted resonances in filters with a very large pass band requirement, is presented. This coupling between the rejection cavities and the main rectangular waveguide has additional advantages; (a) unlike typical inductive irises, large coupling coefficients can be implemented (b) a pure E-plane configuration is achieved, which simplifies the manufacturing and also reduces significantly the computational effort. Experimental validation is demonstrated by two pseudo-elliptic fifth-order band-stop filters fabricated and measured in Ka and V bands. In both cases, the filters are free of spurious resonances in their total operation bands.

  15. NONLINEAR CHARACTERIZATION OF CONCURRENT DUAL-BAND RF POWER AMPLIFIERS

    Institute of Scientific and Technical Information of China (English)

    Hui Ming; Liu Taijun; Ye Yan; Zhang Haili; Shen Dongya; Li Liang

    2012-01-01

    In this paper,the synchronous concurrent dual-band RF signal is used to drive the RF Power Amplifier (PA).The nonlinear characterization of a concurrent dual-band RF PA is discussed while two band signals in the dual-band are modulated by CDMA2000 and WCDMA signals.When the two band signals in the dual-band of the PA are modulated with the same signals,it is found that the nonlinearity of the PA can be expressed by any of the two corresponding baseband data.On the other hand,when the two band signals in the dual-band of the PA are modulated with two different signals,the PA nonlinearity cannot be characterized by any of the two corresponding baseband data.In this case,its nonlinearity has to be denoted by a composite signals consisting of the two baseband signals.Consequently,the requirements for the speed of the A/D converter can be largely reduced.The experimental results with CDMA2000 and WCDMA signals demonstrate the speed of the A/D converter required is only 30 M Sample Per Second (SaPS),but it will be at least 70 M SaPS for the conventional method.

  16. Profile counting

    International Nuclear Information System (INIS)

    In ''profile counting'', a counter is moved progressively along the whole length of the body, and is so collimated that, at each position, it records the radioisotope content of the whole width of the body, but of only a short section of its length. If the counting rate at each position is plotted against the distance of the counter from the vertex of the head, the ''profile'' so obtained gives a rapid and quantitative measure of the radioisotope distribution throughout the body. When a suitable isotope is selectively concentrated in certain organs or tissues of the body, the profile will show peaks indicative of the sites and extent of such concentration, the organs concerned being identified by two-dimensional mapping, and profile counts continued to follow the turnover or changes of concentration in these organs. This technique has been used in the study of I131 concentration and metabolism in thyroid carcinomata, and its value in the management of the radioiodine treatment of such tumours will be discussed. It has also been used in examining the distribution of labelled thyroxine and triiodothyronine after intravenous administration, and of yttrium-90 oxide particles after intrapulmonary artery injection; and of other isotopes by gamma radiation or bremsstrahlung. The method gives a clinically convenient simplification of whole body mapping which lends itself particularly to the quantitative comparison of isotope distribution at different intervals after a radioisotope dose, or after successive doses. (author)

  17. Electronic band structures of binary skutterudites

    International Nuclear Information System (INIS)

    The electronic properties of complex binary skutterudites, MX3 (M = Co, Rh, Ir; X = P, As, Sb) are explored, using various density functional theory (DFT) based theoretical approaches including Green's Function (GW) as well as regular and non-regular Tran Blaha modified Becke Jhonson (TB-mBJ) methods. The wide range of calculated bandgap values for each compound of this skutterudites family confirm that they are theoretically as challenging as their experimental studies. The computationally expensive GW method, which is generally assume to be efficient in the reproduction of the experimental bandgaps, is also not very successful in the calculation of bandgaps. In this article, the issue of the theoretical bandgaps of these compounds is resolved by reproducing the accurate experimental bandgaps, using the recently developed non-regular TB-mBJ approach, based on DFT. The effectiveness of this technique is due to the fact that a large volume of the binary skutterudite crystal is empty and hence quite large proportion of electrons lie outside of the atomic spheres, where unlike LDA and GGA which are poor in the treatment of these electrons, this technique properly treats these electrons and hence reproduces the clear electronic picture of these compounds. - Highlights: • Theoretical and experimental electronic band structures of binary skutterudites are reviewed. • The literature reveals that none of the existing theoretical results are consistent with the experiments. • GW, regular and non-regular TB-mBJ methods are used to reproduce the correct results. • The GW and regular TB-mBJ results are better than the available results in literature. • However, non-regular TB-mBJ reproduces the correct experimental band structures

  18. Electronic band structures of binary skutterudites

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Banaras [Center for Computational Materials Science, University of Malakand, Chakdara (Pakistan); Department of Physics, University of Malakand, Chakdara (Pakistan); Aliabad, H.A. Rahnamaye [Department of Physics, Hakim Sabzevari University, Sabzevar (Iran, Islamic Republic of); Saifullah [Center for Computational Materials Science, University of Malakand, Chakdara (Pakistan); Department of Physics, University of Malakand, Chakdara (Pakistan); Jalali-Asadabadi, S. [Department of Physics, Faculty of Science, University of Isfahan (UI), 81744 Isfahan (Iran, Islamic Republic of); Khan, Imad [Center for Computational Materials Science, University of Malakand, Chakdara (Pakistan); Department of Physics, University of Malakand, Chakdara (Pakistan); Ahmad, Iftikhar, E-mail: ahma5532@gmail.com [Center for Computational Materials Science, University of Malakand, Chakdara (Pakistan); Department of Physics, University of Malakand, Chakdara (Pakistan)

    2015-10-25

    The electronic properties of complex binary skutterudites, MX{sub 3} (M = Co, Rh, Ir; X = P, As, Sb) are explored, using various density functional theory (DFT) based theoretical approaches including Green's Function (GW) as well as regular and non-regular Tran Blaha modified Becke Jhonson (TB-mBJ) methods. The wide range of calculated bandgap values for each compound of this skutterudites family confirm that they are theoretically as challenging as their experimental studies. The computationally expensive GW method, which is generally assume to be efficient in the reproduction of the experimental bandgaps, is also not very successful in the calculation of bandgaps. In this article, the issue of the theoretical bandgaps of these compounds is resolved by reproducing the accurate experimental bandgaps, using the recently developed non-regular TB-mBJ approach, based on DFT. The effectiveness of this technique is due to the fact that a large volume of the binary skutterudite crystal is empty and hence quite large proportion of electrons lie outside of the atomic spheres, where unlike LDA and GGA which are poor in the treatment of these electrons, this technique properly treats these electrons and hence reproduces the clear electronic picture of these compounds. - Highlights: • Theoretical and experimental electronic band structures of binary skutterudites are reviewed. • The literature reveals that none of the existing theoretical results are consistent with the experiments. • GW, regular and non-regular TB-mBJ methods are used to reproduce the correct results. • The GW and regular TB-mBJ results are better than the available results in literature. • However, non-regular TB-mBJ reproduces the correct experimental band structures.

  19. Simple band model of doped fullerene crystal

    International Nuclear Information System (INIS)

    We used quantum billiard with many scattering centers to describe conducting electrons properties in AC60 crystals, where A denotes alkali metal. We focus our attention on the A3C60 crystal, for which we calculate the band structure, density of states, and conductivity for normal electrons. Conductivity shows linear dependence on temperature in this model, which agrees well with experimental data. We also discuss consequences of our results for superconductivity mechanism in A3C60 and possibilities of analogous approach to describe electron properties in fused fullerenes and multiply connected carbon clusters. (author)

  20. Band structure of 79Br

    International Nuclear Information System (INIS)

    High-spin states of 79Br have been studied in the reaction 76Ge(7Li, 4nγ) at 32 MeV. A gamma-detector array with twelve Compton-suppressed HPGe detectors was used. The positive-parity yrast states, interpreted as a rotationally aligned g(9(2)) proton band, and the negative-parity ground state band have been extended to spins of (33(2+)) and (25(2-)), respectively. Lifetime measurements indicate that both bands have a similar quadrupole deformation of β2 ∼ 0.2. The positive-parity α = -(1(2)) band has been identified. Several new inter-band transitions are observed. A cranked-shell model analysis shows that the νg(9(2)) and πg(9(2)) alignments occur in the positive-parity and the negative-parity bands at rotational frequencies of ℎω ∼ 0.6 and 0.4 MeV, respectively. The level energies and the electromagnetic properties of the g(9(2)) band can be well reproduced by a particle-rotor model calculation with an axially symmetric core

  1. Direct band gap measurement of Cu(In,Ga)(Se,S){sub 2} thin films using high-resolution reflection electron energy loss spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Sung [Analytical Engineering Group, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803 (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University, Cheoncheon-dong 300, Jangan-gu, Suwon 440-746 (Korea, Republic of); Lee, Hyung-Ik; Park, Jong-Bong; Ko, Dong-Su; Chung, JaeGwan; Kim, KiHong; Kim, Seong Heon; Yun, Dong-Jin; Ham, YongNam; Park, Gyeong Su [Analytical Engineering Group, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803 (Korea, Republic of); Song, Taewon [Energy lab, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803 (Korea, Republic of); Lee, Dongho, E-mail: dhlee0333@gmail.com; Nam, Junggyu [PV Development Team, Energy Solution Business Division, Samsung SDI, 467 Beonyeong-ro, Cheonan-si, Chungcheongnam-do 331-330 (Korea, Republic of); Kang, Hee Jae [Department of Physics, Chungbuk National University, Gaesin-dong, Heungdeok-gu, Cheongju, 361-763 (Korea, Republic of); Choi, Pyung-Ho; Choi, Byoung-Deog, E-mail: bdchoi@skku.edu [College of Information and Communication Engineering, Sungkyunkwan University, Cheoncheon-dong 300, Jangan-gu, Suwon 440-746 (Korea, Republic of)

    2015-06-29

    To investigate the band gap profile of Cu(In{sub 1−x},Ga{sub x})(Se{sub 1−y}S{sub y}){sub 2} of various compositions, we measured the band gap profile directly as a function of in-depth using high-resolution reflection energy loss spectroscopy (HR-REELS), which was compared with the band gap profile calculated based on the auger depth profile. The band gap profile is a double-graded band gap as a function of in-depth. The calculated band gap obtained from the auger depth profile seems to be larger than that by HR-REELS. Calculated band gaps are to measure the average band gap of the spatially different varying compositions with respect to considering its void fraction. But, the results obtained using HR-REELS are to be affected by the low band gap (i.e., out of void) rather than large one (i.e., near void). Our findings suggest an analytical method to directly determine the band gap profile as function of in-depth.

  2. Direct band gap measurement of Cu(In,Ga)(Se,S)2 thin films using high-resolution reflection electron energy loss spectroscopy

    International Nuclear Information System (INIS)

    To investigate the band gap profile of Cu(In1−x,Gax)(Se1−ySy)2 of various compositions, we measured the band gap profile directly as a function of in-depth using high-resolution reflection energy loss spectroscopy (HR-REELS), which was compared with the band gap profile calculated based on the auger depth profile. The band gap profile is a double-graded band gap as a function of in-depth. The calculated band gap obtained from the auger depth profile seems to be larger than that by HR-REELS. Calculated band gaps are to measure the average band gap of the spatially different varying compositions with respect to considering its void fraction. But, the results obtained using HR-REELS are to be affected by the low band gap (i.e., out of void) rather than large one (i.e., near void). Our findings suggest an analytical method to directly determine the band gap profile as function of in-depth

  3. Collective bands in superdeformed nuclei

    International Nuclear Information System (INIS)

    The collective properties of excited superdeformed bands have been investigated in the framework of self-consistent cranked Nilsson plus quasiparticle random-phase approximation. The expected octupole nature of some bands observed recently in some nuclei has been confirmed by a comparative analysis of their E1 decays to the yrast band and of the anomalous behavior of their dynamical moment of inertia. It is also shown that the onset of supederformation affects considerably the structure of the giant resonances and greatly enhances the collectivity of the low-lying scissors mode. (author)

  4. Rotational Bands in 172W

    Science.gov (United States)

    Greenberg, J.; Guess, C. J.; Tandel, S.; Chowdhury, P.; Carpenter, M. P.; Hartley, D. J.; Janssens, R. V. F.; Khoo, T. L.; Lauritsen, T.; Lister, C. J.; Seweryniak, D.; Shirwadkar, U.; Wang, X.; Zhu, S.

    2015-10-01

    Studying the structure of rotational bands in 172W is valuable for gaining a better understanding of deformed nuclei. Highly excited states of the isotope were populated from a 230 MeV 50Ti beam incident on a 128Te target at Argonne National Laboratory using the ATLAS accelerator. γ emissions from 172W in the range were measured using Compton suppressed germanium detectors in the Gammasphere array. Using this data, three new rotational bands were found, and several other bands were expanded. Swarthmore College Summer Research Fellowship.

  5. Application of the collective model to determine the rotation bands and vibrational bands of 152Sm and 152Gd nucleus

    International Nuclear Information System (INIS)

    The research of nuclear reactions is necessary to identify the specific characteristics of nucleus and it is the most effective experimental method up to now. However, in order to explain the properties of nuclear structures, in addition to the study of the nuclear reactions, nuclear structure models to explain experimental dat and its theory must be used. There are many nuclear structure models to solve those properties of nucleus. This paper presents a collective model application to identify some of rotational bands and vibrational bands of 152 Sm and 152Gd nucleus which result from beta decay of 152Eu source the. (author)

  6. Some parallel banded system solvers

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J.J.; Sameh, A.H.

    1984-12-01

    This paper describes algorithms for solving narrow banded systems and the Helmholtz difference equations that are suitable for multiprocessing systems. The organization of the algorithms highlight the large grain parallelism inherent in the problems. 13 references, 5 tables.

  7. Studies on column size scale-up and flow profile in conical shape liquid chromatographic column of 10° by visualization method

    Institute of Scientific and Technical Information of China (English)

    Guan Wenna; Tan Feng; Guan Yafeng

    2006-01-01

    An improved visualization device made of polymethyl methacrylate (PMMA) was used to study the 3D flow profile inside conical columns of a 10° opening angle packed with C18 phase.The outside wall of the conical columns was rectangular in shape in order to improve the transparency property of the column wall and reduce the deformation of the image for better observation of the flow profiles of colored solutes inside the column.The influence of flow rate,particle size and shape on the flow profile of a colored band were studied on a 5-cm-long column and a scaled-up column of four fold in volume.It was found that the flow rates of the mobile phase had little influence on the flat flow profile of the iodine band while the properties of the stationary phase had a certain influence on them.We observed that the flow profiles of the scaled-up column were flat during the whole chromatographic process,and the efficiency and resolution of the column were also increased in accordance with theoretical prediction.The experimental results proved that the 10° conical columns can be proportionally scaled up while still keeping the flat flow profile,sample load per unit volume of packing material,and column efficiency,which are superior to the conventional column.

  8. Narrow-Band Microwave Filters

    Directory of Open Access Journals (Sweden)

    A.V. Strizhachenko

    2010-01-01

    Full Text Available Original design of the narrow-band compact filters based on the high-quality waveguide-dielectric resonator with anisotropic materials has been presented in this work. Designed filters satisfy the contradictory requirements: they provide the narrow frequency band (0.05 ÷ 0.1 % of the main frequency f0 and the low initial losses α0 ≤ 1 dB.

  9. Dipole Bands in 196Hg

    International Nuclear Information System (INIS)

    High spin states in 196Hg have been populated in the 198Pt(α,6n) reaction at 65 MeV and the level scheme has been extended. A new dipole band has been observed and a previously observed dipole has been confirmed. Excitation energies, spins and parities of these bands were determined from DCO ratio and linear polarization measurements. Possible quasiparticle excitations responsible for these structures are discussed.

  10. Magnetic Compton profiles of Fe by effective potentials

    Energy Technology Data Exchange (ETDEWEB)

    Tokii, M; Matsumoto, M [Graduate School of Library, Information and Media Studies, University of Tsukuba, Tsukuba-shi, Ibaraki 305-8550 (Japan)

    2006-04-19

    Many studies of the ferromagnetic metal Fe have been reported and discussed, such as spin-polarized band calculations, photoemissions, dHvA (de Haas-van Alphen) experiments and Compton profiles experiments. However, theoretical magnetic Compton profiles (MCPs) of bcc Fe are not in good agreement with experimental results, especially in the low momentum region. It is said that this discrepancy is caused in the local spin density approximation (LSDA). Kubo et al calculated the MCPs of bcc Fe with full-potential linearized augmented plane wave (FLAPW) method and lowering the centre of gravity of the p-states. Their results are in good agreement with the experimental one. Recently, we suggested a new LSDA +U method which is effective for metals. For nonmagnetic state bcc V and bcc Cr, the shape of the Fermi surfaces and the population of the d {epsilon} orbital are improved. In this paper, we show that our LSDA +U method improves the size of the N-centred hole pocket and MCPs for ferromagnetic Fe. We used a modified WIEN97 package by adding two kinds of LSDA +U versions, LSDA +U{sup DFT} and LSDA +U{sup 1.0}. In the self-consistent field (SCF) calculation, the fixed-spin-moment scheme is applied.

  11. Magnetic Compton profiles of Fe by effective potentials

    International Nuclear Information System (INIS)

    Many studies of the ferromagnetic metal Fe have been reported and discussed, such as spin-polarized band calculations, photoemissions, dHvA (de Haas-van Alphen) experiments and Compton profiles experiments. However, theoretical magnetic Compton profiles (MCPs) of bcc Fe are not in good agreement with experimental results, especially in the low momentum region. It is said that this discrepancy is caused in the local spin density approximation (LSDA). Kubo et al calculated the MCPs of bcc Fe with full-potential linearized augmented plane wave (FLAPW) method and lowering the centre of gravity of the p-states. Their results are in good agreement with the experimental one. Recently, we suggested a new LSDA +U method which is effective for metals. For nonmagnetic state bcc V and bcc Cr, the shape of the Fermi surfaces and the population of the d ε orbital are improved. In this paper, we show that our LSDA +U method improves the size of the N-centred hole pocket and MCPs for ferromagnetic Fe. We used a modified WIEN97 package by adding two kinds of LSDA +U versions, LSDA +UDFT and LSDA +U1.0. In the self-consistent field (SCF) calculation, the fixed-spin-moment scheme is applied

  12. Emission bands of phosphorus and calculation of band structure of rare earth phosphides

    International Nuclear Information System (INIS)

    The method of x-ray emission spectroscopy has been used to investigate the electronic structure of monophosphides of rare-earth metals (REM). The fluorescence K bands of phosphorus have been obtained in LaP, PrP, SmP, GdP, TbP, DyP, HoP, ErP, TmP, YbP, and LuP and also the Lsub(2,3) bands of phosphorus in ErP, TmP, YbP, and LuP. Using the Green function technique involving the muffin-tin potential, the energy spectrum for ErP has been calculated in the single-electron approximation. The hystogram of electronic state distribution N(E) is compared with the experimental K and Lsub(2,3) bands of phosphorus in ErP. The agreement between the main details of N(E) and that of x-ray spectra allows to state that the model used provides a good description of the electron density distribution in crystals of REM monophosphides. In accordance with the character of the N(E) distribution the compounds under study are classified as semimetals or semiconductors with a very narrow forbidden band

  13. Quasi phase transition model of shear bands in metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Liu Zengqian [Key Laboratory of Aerospace Materials and Performance, School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Li Ran, E-mail: liran@buaa.edu.cn [Key Laboratory of Aerospace Materials and Performance, School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Wang Gang [Department of Materials Science and Engineering, Shanghai University, Shanghai (China); Wu Sujun; Lu Xuyang [Key Laboratory of Aerospace Materials and Performance, School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Zhang Tao, E-mail: zhangtao@buaa.edu.cn [Key Laboratory of Aerospace Materials and Performance, School of Materials Science and Engineering, Beihang University, Beijing 100191 (China)

    2011-11-15

    A quasi phase transition model of shear bands in metallic glasses (MGs) is presented from the thermodynamic viewpoint. Energy changes during shear banding in a sample-machine system are analyzed following fundamental energy theorems. Three characteristic parameters, i.e. the critical initiation energy {Delta}G{sub c}, the shear band stability index k{sub 0}, and the critical shear band length l{sub c}, are derived to elucidate the initiation and propagation of shear bands. The criteria for good plasticity in MGs with predominant thermodynamic arrest of shear bands are proposed as low {Delta}G{sub c}, large k{sub 0}, and small l{sub c}. The model, combined with experimental results, is used to analyze some controversial phenomena of deformation behavior in MGs, such as the size effect, the effect of testing machine stiffness and the relationship between elastic modulus and plasticity. This study has important implications for a fundamental understanding of shear banding as well as deformation mechanisms in MGs and provides a theoretical basis for improving the ductility of MGs.

  14. Multi-band terahertz active device with complementary metamaterial

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Shen; Zhang, Yaxin, E-mail: Zhangyaxin@uestc.edu.cn; Sun, Linlin; Sun, Han; Xu, Gaiqi; Zhao, Yuncheng; Yang, Ziqiang [Terahertz Science Cooperative Innovation Center, University of Electronic Science and Technology of China, Chengdu 610054 (China); Liang, Shixiong [National Key Laboratory of Application Specific Integrated Circuit, Hebei Semiconductor Research Institute, Shijiazhuang 050051 (China)

    2015-09-28

    We describe a multi-band terahertz-active device using a composite structure made of complementary metamaterial and doped silicon that can be dynamically controlled. This special complementary metamaterial exhibits three resonances that produce three pass-bands. The pass-bands can be uniformly manipulated by exploiting the photoinduced characteristics of the doped silicon. Simulations were performed to analyze the magnetic field and surface current distributions. The simulation results agree well with experimental results obtained from terahertz time-domain spectroscopy. Using an 808-nm-wavelength laser beam, a modulation depth of up to 80% was obtained. In numerical simulations, we used a conductivity mode to characterize photoinduction. The development of multi-band terahertz-active devices has many potential applications, for example, in filters, modulators, switches, and sensors.

  15. Atlas of rotational bands in odd-mass nuclei

    International Nuclear Information System (INIS)

    On the ground of a file of the evaluated nuclear data ENSDF the most complete compilation of rotational bands in odd-mass nuclei with mass numbers 43≤A≤253 is presented. The processing of experimental data is carried out on the basis of generalization of the variable moment of inertia model for axial strong deformed nuclei which is taking into account the decoupling effect for bands with K = 1/2. The good description of rotational energies for the majority of rotational bands is obtained and the systematic behavior of the model parameters in all areas of the deformed nuclei is shown. The theoretical description is used for association of fragments of rotational bands, exclusion of 'superfluous' levels and prediction of a placement of 'missed' levels. (author)

  16. True photonic band-gap mode-control in VCSEL structures

    DEFF Research Database (Denmark)

    Romstad, F.; Madsen, M.; Birkedal, Dan;

    2003-01-01

    Photonic band-gap mode confinement in novel nano-structured large area VCSEL structures is confirmed by the amplified spontaneous emission spectrum. Both guide and anti-guide VCSEL structures are experimentally characterised to verify the photonic band-gap effect.......Photonic band-gap mode confinement in novel nano-structured large area VCSEL structures is confirmed by the amplified spontaneous emission spectrum. Both guide and anti-guide VCSEL structures are experimentally characterised to verify the photonic band-gap effect....

  17. Observation of a localized flat-band state in a photonic Lieb lattice

    CERN Document Server

    Mukherjee, Sebabrata; Choudhury, Debaditya; Goldman, Nathan; Öhberg, Patrik; Andersson, Erika; Thomson, Robert R

    2014-01-01

    We show experimentally how a non-diffracting state can be excited in a photonic Lieb lattice. This lattice supports three energy bands, including a perfectly flat middle band, which corresponds to an infinite effective mass with zero dispersion. We show that a suitable optical input state can be prepared so as to only excite the flat band. We analyse, both experimentally and theoretically, the evolution of such photonic flat-band states, and show their remarkable robustness, even in the presence of disorder.

  18. Photonic bands in two-dimensional microplasma arrays. II. Band gaps observed in millimeter and subterahertz ranges

    International Nuclear Information System (INIS)

    Plasma photonic band gaps have been observed in a two-dimensional microplasma array, and we have characterized their properties by both experimental and theoretical results. Microplasma columns ignited in helium near atmospheric pressure formed crystal-like structures in a square lattice with a lattice constant from 1.5 to 2.5 mm. Microwaves in the millimeter range transmitting through the array region attenuated at frequencies of photonic band gap in the Γ-X direction, as predicted by the modified plane-wave expansion method. Frequency dependence around the band gap was clarified in the numerical analysis of electromagnetic wave propagation and agreed with experimental results. Electron density in microplasmas was estimated to be 1x1013 cm-3 from the attenuation rate at the band gap in the Γ-X direction. Variation of the lattice constant induced frequency shift of the band gap in the millimeter and subterahertz regions, and so plasma photonic crystal can perform as a dynamically controllable band-stop filter

  19. The width of Liesegang bands: A study using moving boundary model and simulation

    Indian Academy of Sciences (India)

    Shibi Thomas; George Varghese; István Lagzi

    2012-01-01

    The pattern formation in reaction–diffusion systems was studied by invoking the provisions contained in the moving boundary model. The model claims that the phase separation mechanism is responsible for separating the colloidal phase of precipitants into band and non-band regions. The relation between the band separation and its width are invariably related to the concentration of the reacting components. It was observed that this model provides critical condition for the band formation in semi-idealized diffusion systems. An algorithm for generating the band structure was designed, and the simulated pattern shows a close resemblance with the experimentally observed ones.

  20. Simple method of obtaining the band strengths in the electronic spectra of diatomic molecules

    International Nuclear Information System (INIS)

    It is shown that relative band strengths of diatomic molecules for which the product of Franck-Condon factor and r-centroid is approximately equal to 1 for (0,0) band can be determined by a simple method which is in good agreement with the smoothed array of experimental values. Such values for the Swan bands of the C2 molecule are compared with the band strengths of the simple method. It is noted that the Swan bands are one of the outstanding features of R- and N-type stars and of the heads of comets

  1. Identification of New Hot Bands in the Blue and Green Band Systems of FeH.

    Science.gov (United States)

    Wilson; Brown

    1999-10-01

    A particularly rich region of the electronic spectrum of FeH from 525 to 545 nm was investigated using the techniques of dispersed and undispersed laser-induced fluorescence. Analysis has led to the discovery that several different electronic transitions are embedded in this region; the (0, 0) and (1, 1) bands of the e(6)Pi-a(6)Delta (green) system, the (0, 2) band of the g(6)Phi-X(4)Delta (intercombination) system, the (0, 1) band of the g(6)Phi-a(6)Delta (blue) system, and the (0, 0) band of the g(6)Phi-b(6)Pi system. Seventy-five lines were assigned in the (0, 1) band of the g(6)Phi-a(6)Delta transition. These, with the assignment of an additional 14 lines in the 583 nm region to the (0, 1) band of the e(6)Pi-a(6)Delta transition, led to the extension of the known term values to higher J values for the Omega = 9/2, 7/2, and 5/2 spin components of the v = 1 level of the a(6)Delta state and the novel characterization of the a(6)Delta(3/2) (v = 1) and g(6)Phi(5/2) (v = 0) components. A further 73 lines were assigned to the first four subbands of the (1, 1) band of the e(6)Pi-a(6)Delta transition and term values for the lowest four spin components of the v = 1 level of the e(6)Pi state were determined. This provides the first experimental measurement of a vibrational interval in one of the higher lying electronic states of FeH. The interval does not appear to vary strongly between the spin components (DeltaG(1/2) = 1717, 1713, 1710 cm(-1) for Omega = 7/2, 5/2, 3/2, respectively). Remarkably few of the hot-band transitions assigned in this work could be identified in the complex, high-temperature spectrum of FeH recorded by P. McCormack and S. O'Connor [Astron. Astrophys. Suppl. 26, 373-380 (1976)]. Copyright 1999 Academic Press. PMID:10479583

  2. Information retrieval from wide-band meteorological data - An example

    Science.gov (United States)

    Adelfang, S. I.; Smith, O. E.

    1983-01-01

    The methods proposed by Smith and Adelfang (1981) and Smith et al. (1982) are used to calculate probabilities over rectangles and sectors of the gust magnitude-gust length plane; probabilities over the same regions are also calculated from the observed distributions and a comparison is also presented to demonstrate the accuracy of the statistical model. These and other statistical results are calculated from samples of Jimsphere wind profiles at Cape Canaveral. The results are presented for a variety of wavelength bands, altitudes, and seasons. It is shown that wind perturbations observed in Jimsphere wind profiles in various wavelength bands can be analyzed by using digital filters. The relationship between gust magnitude and gust length is modeled with the bivariate gamma distribution. It is pointed out that application of the model to calculate probabilities over specific areas of the gust magnitude-gust length plane can be useful in aerospace design.

  3. Ab-initio determination of X-ray structure factors and the Compton profiles of CdO

    International Nuclear Information System (INIS)

    X-ray structure factors and Compton profiles of CdO are presented in this work. The theoretical calculations are performed employing the first-principles linear combination of atomic orbitals (LCAO) method using the CRYSTAL code. The computations are made considering the Perdew-Burke-Ernzerhof (PBE) correlation energy functional and Becke's ansatz for the exchange. The computed X-ray structure factors for B1 structure are compared with the available experimental data. To compare the averaged theoretical Compton profile, first ever measurement on polycrystalline CdO is reported using 5Ci 241Am Compton spectrometer. The ionic model calculations have been used to estimate charge transfer in CdO. The agreement is, however, better with the LCAO calculation. The first-principles calculations of equilibrium lattice constants, bulk moduli and its pressure derivative of competing B1 and B2 phases of CdO are also reported and compared with the available results. The computed transition pressure for B1 → B2 structural phase transition is in good agreement with the experimental findings. Moreover, the electronic band structures show that B1 phase has indirect band gap of 0.43 eV in reasonable agreement with the experiments and B2 phase exhibits negative band gap of 0.9 eV.

  4. MPI Profiling

    Energy Technology Data Exchange (ETDEWEB)

    Han, D K; Jones, T R

    2005-02-11

    The Message Passing Interface (MPI) is the de facto message-passing standard for massively parallel programs. It is often the case that application performance is a crucial factor, especially for solving grand challenge problems. While there have been many studies on the scalability of applications, there have not been many focusing on the specific types of MPI calls being made and their impact on application performance. Using a profiling tool called mpiP, a large spectrum of parallel scientific applications were surveyed and their performance results analyzed.

  5. Band structure of a three-dimensional topological insulator quantum wire in the presence of a magnetic field

    Science.gov (United States)

    Liu, Zhe; Jiang, Liwei; Zheng, Yisong

    2016-07-01

    By means of a numerical diagonalization approach, we calculate the electronic structure of a three-dimensional topological insulator (3DTI) quantum wire (QW) in the presence of a magnetic field. The QW can be viewed as a 3DTI film with lateral surfaces, when its rectangular cross section has a large aspect ratio. Our calculation indicates that nonchiral edge states emerge because of the confined states at the lateral surfaces. These states completely cover the valence band region among the Landau levels, which reasonably account for the absence of the ν Hall effect in the relevant experimental works. In an ultrathin 3DTI film, inversion between the electron-type and hole-type bands occurs, which leads to the so-called pseudo-spin Hall effect. In a 3DTI QW with a square cross section, a tilting magnetic field can establish well-defined Landau levels in all four surfaces. In such a case, the quantum Hall edge states are localized at the square corners, characterized by the linearly crossing one-dimensional band profile. And they can be shifted between the adjacent corners by simply rotating the magnetic field.

  6. Band structure of a three-dimensional topological insulator quantum wire in the presence of a magnetic field.

    Science.gov (United States)

    Liu, Zhe; Jiang, Liwei; Zheng, Yisong

    2016-07-13

    By means of a numerical diagonalization approach, we calculate the electronic structure of a three-dimensional topological insulator (3DTI) quantum wire (QW) in the presence of a magnetic field. The QW can be viewed as a 3DTI film with lateral surfaces, when its rectangular cross section has a large aspect ratio. Our calculation indicates that nonchiral edge states emerge because of the confined states at the lateral surfaces. These states completely cover the valence band region among the Landau levels, which reasonably account for the absence of the [Formula: see text] quantum Hall effect in the relevant experimental works. In an ultrathin 3DTI film, inversion between the electron-type and hole-type bands occurs, which leads to the so-called pseudo-spin Hall effect. In a 3DTI QW with a square cross section, a tilting magnetic field can establish well-defined Landau levels in all four surfaces. In such a case, the quantum Hall edge states are localized at the square corners, characterized by the linearly crossing one-dimensional band profile. And they can be shifted between the adjacent corners by simply rotating the magnetic field. PMID:27195483

  7. Band loss by nestling mourning doves

    Science.gov (United States)

    Kaczynski, C.F.; Kiel, W.H.

    1963-01-01

    Nestling mourning doves (Zenaidura macroura) were banded and checked for band loss prior to fledging at Parchman, Mississippi, during the months of June-August, 1960. Three hundred seventy-seven nestlings 4-6 days of age were banded, 117 with size 3 bands, 120 with size 3A bands, and 140 with size 3A bands secured by Dalzoflex tape. Two hundred twenty nestlings 7-9 days of age were banded, 114 with size 3 bands and 106 with size 3A bands. In the 4- to 6-day age group, 66.3 percent of the size 3A bands were lost. This was a statistically significant departure from the 7.7 percent loss of size 3 bands. No taped bands were lost. However, predators ate 13.8 percent of the nestlings with taped bands and significantly fewer of the nestlings banded without tape. In the 4- to 6-day age group, percentages of nestlings known to be available for band recovery at 9 days or older were: size 3, 69.2 percent; size 3A with tape, 59.0 percent; size 3A, 25.8 percent. In the 7-to 9-day age group, there was a 3.3 percent loss of size 3A bands and no loss of size 3 bands. The minimum age at which nestlings were banded without subsequent loss of bands was 6 days for size 3 and 8 days for size 3A.

  8. W-Band Planar Wide-Angle Scanning Antenna Architecture

    OpenAIRE

    Zelenchuk, Dmitry; Martinez-Ros, AlejandroJavier; Zvolensky, Tomas; Gomez-Tornero, JoseLuis; Goussetis, George; Buchanan, Neil; Linton, David; Fusco, Vincent

    2013-01-01

    This paper proposes a hybrid scanning antenna architecture for applications in mm-wave intelligent mobile sensing and communications. We experimentally demonstrate suitable W-band leaky-wave antenna prototypes in substrate integrated waveguide (SIW) technology. Three SIW antennas have been designed that within a 6.5 % fractional bandwidth provide beam scanning over three adjacent angular sectors. Prototypes have been fabricated and their performance has been experimentally evaluated. The meas...

  9. Surface Brightness Profiles of Dwarf Galaxies: I. Profiles and Statistics

    CERN Document Server

    Herrmann, Kimberly A; Elmegreen, Bruce G

    2013-01-01

    Radial surface brightness profiles of spiral galaxies are classified into three types: (I) single exponential, or the light falls off with one exponential to a break before falling off (II) more steeply, or (III) less steeply. Profile breaks are also found in dwarf disks, but some dwarf Type IIs are flat or increasing out to a break before falling off. Here we re-examine the stellar disk profiles of 141 dwarfs: 96 dwarf irregulars (dIms), 26 Blue Compact Dwarfs (BCDs), and 19 Magellanic-type spirals (Sms). We fit single, double, or even triple exponential profiles in up to 11 passbands: GALEX FUV and NUV, ground-based UBV JHK and H{\\alpha}, and Spitzer 3.6 and 4.5 {\\mu}m. We find that more luminous galaxies have brighter centers, larger inner and outer scale lengths, and break at larger radii; dwarf trends with M_B extend to spirals. However, the V-band break surface brightness is independent of break type, M_B, and Hubble type. Dwarf Type II and III profiles fall off similarly beyond the breaks but have diff...

  10. In-band and inter-band B(E2) values within the Triaxial Projected Shell Model

    International Nuclear Information System (INIS)

    The Triaxial Projected Shell Model (TPSM) has been successful in providing a microscopic description of the energies of multi-phonon vibrational bands in deformed nuclei. We report here on an extension of the TPSM to allow, for the first time, calculations of B(E2) values connecting γ- and γγ-vibrational bands and the ground-state band. The method is applied to 166,168Er. It is shown that most of the existing B(E2) data can be reproduced rather well, thus strongly supporting the classification of these states as γ-vibrational states. However, significant differences between the data and the calculation are seen in those B(E2) values which involve odd-spin states of the γ-band. Understanding these discrepancies requires accurate experimental measurements and perhaps further improvements of the TPSM. (orig.)

  11. Photonic Band Gap structures: A new approach to accelerator cavities

    Energy Technology Data Exchange (ETDEWEB)

    Kroll, N. [California Univ., San Diego, La Jolla, CA (United States). Dept. of Physics]|[Stanford Linear Accelerator Center, Menlo Park, CA (United States); Smith, D.R.; Schultz, S. [California Univ., San Diego, La Jolla, CA (United States). Dept. of Physics

    1992-12-31

    We introduce a new accelerator cavity design based on Photonic Band Gap (PGB) structures. The PGB cavity consists of a two-dimensional periodic array of high dielectric, low loss cylinders with a single removal defect, bounded on top and bottom by conducting sheets. We present the results of both numerical simulations and experimental measurements on the PGB cavity.

  12. Quantum interference of independently generated telecom-band single photons

    International Nuclear Information System (INIS)

    We report on high-visibility quantum interference of independently generated telecom O-band (1310 nm) single photons using standard single-mode fibers. The experimental data are shown to agree well with the results of simulations using a comprehensive quantum multimode theory without the need for any fitting parameter

  13. Quantum interference of independently generated telecom-band single photons

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Monika [Center for Photonic Communication and Computing, Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112 (United States); Altepeter, Joseph B.; Huang, Yu-Ping; Oza, Neal N. [Center for Photonic Communication and Computing, Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3118 (United States); Kumar, Prem [Center for Photonic Communication and Computing, Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112, USA and Center for Photonic Communication and Computing, Department of Electrical Engineering (United States)

    2014-12-04

    We report on high-visibility quantum interference of independently generated telecom O-band (1310 nm) single photons using standard single-mode fibers. The experimental data are shown to agree well with the results of simulations using a comprehensive quantum multimode theory without the need for any fitting parameter.

  14. Photonic Band Gap structures: A new approach to accelerator cavities

    International Nuclear Information System (INIS)

    We introduce a new accelerator cavity design based on Photonic Band Gap (PGB) structures. The PGB cavity consists of a two-dimensional periodic array of high dielectric, low loss cylinders with a single removal defect, bounded on top and bottom by conducting sheets. We present the results of both numerical simulations and experimental measurements on the PGB cavity

  15. The possible mass region for shears bands and chiral doublets

    Energy Technology Data Exchange (ETDEWEB)

    Meng, J. [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Frauendorf, S.

    1998-03-01

    The Tilted Axis Cranking (TAC) theory is reviewed. The recent progress of TAC for triaxial deformed nuclei is reported. More emphasis has been paid to the new discovered phenomena - chiral doublets and their explanation. The possible mass region for the shears bands and chiral doublets and their experimental signature are discussed. (author)

  16. NOVEL SUPER WIDE BAND ANTENNA WITH WLAN/WiMAX BAND REJECTION AND COMPACT SIZE

    Directory of Open Access Journals (Sweden)

    Hadi Baghali

    2014-01-01

    Full Text Available A 25×25×1.6mm3 implementation of a microstrip-fed printed monopole antenna for the future UWB wireless systems application is presented. It has features of possesses band notched function (from 4.88 to 6.07GHz, extremely wide impedance bandwidth (from 2.58 to 18GHz and its compact size. By using a smooth tapering between the semi fractal-shaped patch and the half ellipse-shaped defected ground plane, the wide impedance bandwidth is achieved with ratio bandwidth larger than 6.97:1. Numerical and experimental results are in good agreement and they indicate that the proposed antenna has a measured 2:1 VSWR bandwidth of 149.8%, except the rejected WLAN band.

  17. Band-to-band tunneling distance analysis in the heterogate electron-hole bilayer tunnel field-effect transistor

    Science.gov (United States)

    Padilla, J. L.; Palomares, A.; Alper, C.; Gámiz, F.; Ionescu, A. M.

    2016-01-01

    In this work, we analyze the behavior of the band-to-band tunneling distance between electron and hole subbands resulting from field-induced quantum confinement in the heterogate electron-hole bilayer tunnel field-effect transistor. We show that, analogously to the explicit formula for the tunneling distance that can be easily obtained in the semiclassical framework where the conduction and valence band edges are allowed states, an equivalent analytical expression can be derived in the presence of field-induced quantum confinement for describing the dependence of the tunneling distance on the body thickness and material properties of the channel. This explicit expression accounting for quantum confinement holds valid provided that the potential wells for electrons and holes at the top and bottom of the channel can be approximated by triangular profiles. Analytical predictions are compared to simulation results showing very accurate agreement.

  18. Band-to-band tunneling distance analysis in the heterogate electron–hole bilayer tunnel field-effect transistor

    International Nuclear Information System (INIS)

    In this work, we analyze the behavior of the band-to-band tunneling distance between electron and hole subbands resulting from field-induced quantum confinement in the heterogate electron–hole bilayer tunnel field-effect transistor. We show that, analogously to the explicit formula for the tunneling distance that can be easily obtained in the semiclassical framework where the conduction and valence band edges are allowed states, an equivalent analytical expression can be derived in the presence of field-induced quantum confinement for describing the dependence of the tunneling distance on the body thickness and material properties of the channel. This explicit expression accounting for quantum confinement holds valid provided that the potential wells for electrons and holes at the top and bottom of the channel can be approximated by triangular profiles. Analytical predictions are compared to simulation results showing very accurate agreement

  19. Band-to-band tunneling distance analysis in the heterogate electron–hole bilayer tunnel field-effect transistor

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, J. L., E-mail: jose.padilladelatorre@epfl.ch [Nanoelectronic Devices Laboratory, École Polytechnique Fédérale de Lausanne, Lausanne CH-1015 (Switzerland); Departamento de Electrónica y Tecnología de los Computadores, Universidad de Granada, Avda. Fuentenueva s/n, 18071 Granada (Spain); Palomares, A. [Departamento de Matemática Aplicada, Universidad de Granada, Avda. Fuentenueva s/n, 18071 Granada (Spain); Alper, C.; Ionescu, A. M. [Nanoelectronic Devices Laboratory, École Polytechnique Fédérale de Lausanne, Lausanne CH-1015 (Switzerland); Gámiz, F. [Departamento de Electrónica y Tecnología de los Computadores, Universidad de Granada, Avda. Fuentenueva s/n, 18071 Granada (Spain)

    2016-01-28

    In this work, we analyze the behavior of the band-to-band tunneling distance between electron and hole subbands resulting from field-induced quantum confinement in the heterogate electron–hole bilayer tunnel field-effect transistor. We show that, analogously to the explicit formula for the tunneling distance that can be easily obtained in the semiclassical framework where the conduction and valence band edges are allowed states, an equivalent analytical expression can be derived in the presence of field-induced quantum confinement for describing the dependence of the tunneling distance on the body thickness and material properties of the channel. This explicit expression accounting for quantum confinement holds valid provided that the potential wells for electrons and holes at the top and bottom of the channel can be approximated by triangular profiles. Analytical predictions are compared to simulation results showing very accurate agreement.

  20. Wild Band Edges: The Role of Bandgap Grading and Band-Edge Fluctuations in High-Efficiency Chalcogenide Devices: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Repins, Ingrid; Mansfield, Lorelle; Kanevce, Ana; Jensen, Soren A.; Kuciauskas, Darius; Glynn, Stephen; Barnes, Teresa; Metzger, Wyatt; Burst, James; Jiang, Chun-Sheng; Dippo, Patricia; Harvey, Steve; Teeter, Glenn; Perkins, Craig; Egaas, Brian; Zakutayev, Andriy; Alsmeier, J.-H.; Lussky, T.; Korte, L.; Wilks, R. G.; Bar, M.; Yan, Y.; Lany, Stephan; Zawadzki, Pawel; Park, Ji-Sang; Wei, Suhuai

    2016-06-16

    Band-edge effects -- including grading, electrostatic fluctuations, bandgap fluctuations, and band tails -- affect chalcogenide device efficiency. These effects now require more careful consideration as efficiencies increase beyond 20%. Several aspects of the relationships between band-edge phenomena and device performance for NREL absorbers are examined. For Cu(In,Ga)Se2 devices, recent increases in diffusion length imply changes to optimum bandgap profile. The origin, impact, and modification of electrostatic and bandgap fluctuations are also discussed. The application of the same principles to devices based on CdTe, kesterites, and emerging absorbers (Cu2SnS3, CuSbS2), considering differences in materials properties and defect formation energies, is examined.

  1. Introduction to the viewpoint set on shear bands

    International Nuclear Information System (INIS)

    Recent work aimed at improving our understanding of shear banding and flow localization as modes of deformation and failure is summarized in the six viewpoint articles which follow. For the most part, the emphasis here is on the observation and analysis of shear banding in metals, but active efforts are also underway to understand the role of shear bands in the deformation and failure of soils and rocks. There is a tendency to regard shear bands as a failure mode, as indeed they often are. But extensive straining under highly constrained conditions such as rolling can give rise to profuse flow localization into shear bands which can be regarded as microscopic in the sense that their extent is on the scale of the grains rather than the overall dimensions of the block of material being deformed. Hatherly and Malin describe in detail the observation of such bands and emphasize that they should be considered as a mode of deformation under these circumstances. They relate the formation of the bands to microstructural aspects and discuss their role in the development of recrystallization textures. It will be clear from reading the articles in this viewpoint set that the beginnings of a quantitative theory of shear banding is in place. Continued progress will require parallel developments in constitutive theory and experimental observation. Moreover, basic questions remain to be explored related to the spatial development of the shear bands, their mutual interaction, their development into a failure mode, and how these are influenced by factors such as overall deformational constraint, rate of straining, and temperature

  2. In situ, meteorological, navigational, physical and profile data collected by Italian National Institute of Oceanography and Experimental Geophysics; Experimental Geophysical Observatory at OceanSITES site E2M3A from 2002-09-16 to 2009-10-13 (NCEI Accession 0130031)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In situ, meteorological, navigational, physical and profile oceanographic data were collected, including AIR TEMPERATURE, BAROMETRIC PRESSURE, CONDUCTIVITY, DEPTH -...

  3. Electronic properties and Compton profiles of silver iodide

    Indian Academy of Sciences (India)

    Alpa Dashora; Ambica Marwal; K R Soni; B L Ahuja

    2010-06-01

    We have carried out an extensive study of electronic properties of silver iodide in - and -phases. The theoretical Compton profiles, energy bands, density of states and anisotropies in momentum densities are computed using density functional theories. We have also employed full-potential linearized augmented plane-wave method to derive the energy bands and the density of states. To compare our theoretical data, isotropic Compton profile measurement on -AgI using 137Cs Compton spectrometer at an intermediate resolution of 0.38 a.u. has been undertaken. The theoretical anisotropies are also interpreted on the basis of energy bands.

  4. First-principles determination of band-to-band electronic transition energies in cubic and hexagonal AlGaInN alloys

    Directory of Open Access Journals (Sweden)

    F. L. Freitas

    2016-08-01

    Full Text Available We provide approximate quasiparticle-corrected band gap energies for quaternary cubic and hexagonal AlxGayIn1–x–yN semiconductor alloys, employing a cluster expansion method to account for the inherent statistical disorder of the system. Calculated values are compared with photoluminescence measurements and discussed within the currently accepted model of emission in these materials by carrier localization. It is shown that bowing parameters are larger in the cubic phase, while the range of band gap variation is bigger in the hexagonal one. Experimentally determined transition energies are mostly consistent with band-to-band excitations.

  5. Direct band gap silicon allotropes.

    Science.gov (United States)

    Wang, Qianqian; Xu, Bo; Sun, Jian; Liu, Hanyu; Zhao, Zhisheng; Yu, Dongli; Fan, Changzeng; He, Julong

    2014-07-16

    Elemental silicon has a large impact on the economy of the modern world and is of fundamental importance in the technological field, particularly in solar cell industry. The great demand of society for new clean energy and the shortcomings of the current silicon solar cells are calling for new materials that can make full use of the solar power. In this paper, six metastable allotropes of silicon with direct or quasidirect band gaps of 0.39-1.25 eV are predicted by ab initio calculations at ambient pressure. Five of them possess band gaps within the optimal range for high converting efficiency from solar energy to electric power and also have better optical properties than the Si-I phase. These Si structures with different band gaps could be applied to multiple p-n junction photovoltaic modules. PMID:24971657

  6. X-Band PLL Synthesizer

    Directory of Open Access Journals (Sweden)

    P. Kutin

    2006-04-01

    Full Text Available This paper deals with design and realization of a PLL synthesizer for the microwave X−band. The synthesizer is intended for use as a local oscillator in a K−band downconverter. The design goal was to achieve very low phase noise and spurious free signal with a sufficient power level. For that purpose a low phase noise MMIC VCO was used in phase locked loop. The PLL works at half the output frequency, therefore there is a frequency doubler at the output of the PLL. The output signal from the frequency doubler is filtered by a band-pass filter and finally amplified by a single stage amplifier.

  7. Bands and Band Termination in 127La%127La转动带及带终止

    Institute of Scientific and Technical Information of China (English)

    董保国; Ragna.,I

    2000-01-01

    The configuration-dependent shell-correction approach with cranked Nilsson potential is employed for explaining the experimental high-spin spectra in 127La. The experimental high spin band with parity and signature (+,-1/2) consists of two parts with a crossing around I=20h. It is most like to have the configuration[02,6], π(h11/2)2v(h11/2)6 and almost reaching the maximum angular momentum at I=47.5 h. It is in normal deformation region with ε2≈0.22 and γ≈0° up to I=40 h and then moving over the γ-plane to termination atγ=60。. Comparing calculations and experiment, one notes that the bands are seen to spin values where according to calculation they start to go away clearly from yrast, thus this supports our interpretation. There are strongly deformed (or superdeformed) bands with ε2≈0.35 and ν≈0°. They were calculated to become yrast for I=40h making it very unlikely that the observed bands were strongly deformed. However, they represent a challenge for future experiments. Below I=21.5 Kthe experimental high spin bands appear to have strong pairing interaction since their moments of inertia go down to 10/2 MeV-1 from I=11.5h to I=19.5 h.%用组态相关推转壳模型Nilsson势研究了C.M.Parry组最近用EUROBALL谱仪观测到的127La高自旋态结构.实验上观测的127La的宇称和辛量子数为(π,α)=(+,-1/2)的带自旋达到(83/2)h.理论计算结果表明该带可能具有组态π(h11/2)2v(h11/2)6.并且几乎达到该带的带终止理论预言值 I=47.5h.该带的形变在I≤40h内处于正常形变区(ε2≈0.22,γ≈0°),随着角动量的增加ν值逐渐增加,直到ν=60°时带终止.

  8. Hyperdeformed band in the 36Ar nucleus?

    International Nuclear Information System (INIS)

    Complete text of publication follows. The exotic shapes of atomic nuclei has attracted much attention recently both from the experimental and from the theoretical sides. E.g. the superdeformed (SD) shape in N = Z nuclei were observed experimentally during the last decade. In particular the SD band of the 36Ar nucleus was detected in 2000 [1]. Following the experimental observation a considerable theoretical effort has been concentrated on this band. In [2] e.g. the possible binary clusterizations of this state was studied systematically. Similar studies have been done also for the ground, and the hyperdeformed band. The latter one had been predicted from alphacluster model calculations [3]. The possible binary cluster-configurations are important not only for the better understanding of the structure of the shape isomers, but also from the viewpoint of predicting the favoured reaction channels to populate these states. This is the straightforward consequence of the close relation between the clusterization and reaction channels. (In fact, a cluster-configuration is defined by the reaction channel in which it can be observed.) One of the interesting conclusions of the work [2] was, that the hyperdeformed (HD) state of the 36Ar nucleus could be populated in the 24Mg+12C and 20Ne+16O reactions. A recent analysis of the 24Mg+12C elastic scattering [4] revealed the fact that the cross section can be described only by supposing resonances on top of the potential scattering. This very careful analysis incorporated phase-shift study, as well as Regge-pole and energy-dependent resonance calculations. The existence of five resonances have been proved, which have angular momenta 2, 4, 6, 7, 8. These states together with the resonances from the 20Ne+16O reactions seem to establish a rotational band, as shown in the upper part of Fig. 1. Its moment of inertia is in a very good agreement with that of the HD shape predicted from alpha-cluster model [3]. The similarity of the

  9. Achieving omnidirectional photonic band gap in sputter deposited TiO2/SiO2 one dimensional photonic crystal

    International Nuclear Information System (INIS)

    The multilayer structure of TiO2/SiO2 (11 layers) as one dimensional photonic crystal (1D PC) has been designed and then fabricated by using asymmetric bipolar pulse DC magnetron sputtering technique for omnidirectional photonic band gap. The experimentally measured photonic band gap (PBG) in the visible region is well matched with the theoretically calculated band structure (ω vs. k) diagram. The experimentally measured omnidirectional reflection band of 44 nm over the incident angle range of 0°-70° is found almost matching within the theoretically calculated band

  10. Analysis of high-temperature thermoelectric properties of p-type CoSb3 within a two-valence-band and two-conduction-band model

    Science.gov (United States)

    Kajikawa, Y.

    2014-05-01

    Experimental data on the thermoelectric properties of p-type CoSb3 reported by Caillat et al. [J. Appl. Phys. 80, 4442 (1996)] have been analyzed, assuming not only a pair of the first valence (v1) and the first conduction (c1) bands but also the second valence (v2) and the second conduction (c2) bands. By taking into account the excitation of carriers into the v2 and the c2 bands, the behavior of the Hall coefficient as well as that of the Seebeck coefficient at high temperatures is well explained. By taking into account the nonparabolicity of the v1 band, the temperature dependence of mobility is well explained with assuming scattering due to acoustic phonons, nonpolar and polar optical phonons, and ionized impurities. Furthermore, various material parameters of CoSb3, such as the band-gap energy, effective masses, and deformation potentials, have been deduced from fitting the calculation to the experimental data on the temperature dependences of the Hall coefficient, the mobility, and the Seebeck coefficient. Among them, the band-gap energy and the effective mass of the v1 band have been corrected from the original values estimated by Caillat et al. In addition, it is shown that the experimental data on the hole-concentration dependences of both the room-temperature Seebeck coefficient and the cyclotron mass are well reproduced by the theoretical calculation using the deduced values for the nonparabolic v1 band.

  11. Shear Banding of Complex Fluids

    Science.gov (United States)

    Divoux, Thibaut; Fardin, Marc A.; Manneville, Sebastien; Lerouge, Sandra

    2016-01-01

    Even in simple geometries, many complex fluids display nontrivial flow fields, with regions where shear is concentrated. The possibility for such shear banding has been known for several decades, but in recent years, we have seen an upsurge in studies offering an ever-more precise understanding of the phenomenon. The development of new techniques to probe the flow on multiple scales with increasing spatial and temporal resolution has opened the possibility for a synthesis of the many phenomena that could only have been thought of separately before. In this review, we bring together recent research on shear banding in polymeric and soft glassy materials and highlight their similarities and disparities.

  12. Parity-Time Symmetry in a Flat Band System

    CERN Document Server

    Ge, Li

    2015-01-01

    In this report we introduce Parity-Time (PT) symmetric perturbation to a one-dimensional Lieb lattice, which is otherwise P-symmetric and has a flat band. In the flat band there are a multitude of degenerate dark states, and the degeneracy N increases with the system size. The half-gain-half-loss perturbation we consider overlaps with the dark states, and we show that both randomly positioned states and pinned states at the symmetry plane in the flat band can undergo thresholdless PT breaking. They are distinguished by their different rates of acquiring non-Hermicity as the PT-symmetric perturbation grows, which are insensitive to the system size. Using a degenerate perturbation theory, we derive analytically the rate for the pinned states, whose spatial profiles are also insensitive to the system size. Finally, we find that the presence of weak disorder has a strong effect on modes in the dispersive bands but not on those in the flat band. The latter response in completely different ways to the growing PT-sy...

  13. Acoustic band gaps of the woodpile sonic crystal with the simple cubic lattice

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Liang-Yu; Chen, Lien-Wen, E-mail: chenlw@mail.ncku.edu.t [Department of Mechanical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China)

    2011-02-02

    This study theoretically and experimentally investigates the acoustic band gap of a three-dimensional woodpile sonic crystal. Such crystals are built by blocks or rods that are orthogonally stacked together. The adjacent layers are perpendicular to each other. The woodpile structure is embedded in air background. Their band structures and transmission spectra are calculated using the finite element method with a periodic boundary condition. The dependence of the band gap on the width of the stacked rods is discussed. The deaf bands in the band structure are observed by comparing with the calculated transmission spectra. The experimental transmission spectra for the {Gamma}-X and {Gamma}-X' directions are also presented. The calculated results are compared with the experimental results.

  14. EDITORIAL: Excelling under strain: band engineering in nanomaterials Excelling under strain: band engineering in nanomaterials

    Science.gov (United States)

    Demming, Anna

    2013-08-01

    A little stress or strain has been known to improve the performance of athletes, actors and of course nanomaterials alike. In fact strain in silicon is now a major engineering tool for improving the performance of devices, and is ubiquitously used in device design and fabrication. Strain engineering alters a material's band structure, a model of electron behaviour that describes how as atoms come together in a solid, their discrete electron orbitals overlap to ultimately give rise to bands of allowed energy levels. In a strained crystal lattice of silicon or silicon germanium the distance between atoms in the lattice is greater than usual and the bands of allowed energy levels change. This July marks 100 years since Bohr submitted his paper 'On the constitution of atoms and molecules' [1] where he describes the structure of the atom in terms of discrete allowed energy levels. The paper was a seminal contribution to the development of quantum mechanics and laid the initial theoretical precepts for band gap engineering in devices. In this issue Nrauda and a collaboration of researchers in Europe and Australia study the growth of defect-free SiGe islands on pre-patterned silicon [2]. They analyse the strain in the islands and determine at what point lattice dislocations set in with a view to informing implementation of strain engineering in devices. The effects of strain on band structure in silicon and germanium were already studied and reported in the 1950s [3, 4]. Since then the increasing focus on nanoscale materials and the hunger for control of electronic properties has prompted further study of strain effects. The increased surface area to volume ratio in nanostructures changes the strain behaviour with respect to bulk materials, and this can also be exploited for handling and fine tuning strain to manipulate material properties. It is perhaps no surprise that graphene, one of the most high-profile materials in current nanotechnology research, has attracted

  15. Critical Free Volume Concentration of Shear Banding Instability in Metallic Glasses

    Institute of Scientific and Technical Information of China (English)

    LIU Long-Fei; CAI Zhi-Peng; LI Hui-Qiang; ZHANG Guang-Ye; GUO Shi-Bo

    2011-01-01

    We present a model which predicts the critical free volume concentration of shear banding instability in metallic glasses(MGs). Fl-om the stability map, this model demonstrates that the prediction of shear band thickness is valid only for a short time after shear instability, and the diffusion of defects should be included in the mature shear band in MGs. The results agree well with the experimental observations and simulations.

  16. Demonstration of the spatial separation of the entangled quantum side-bands of an optical field

    CERN Document Server

    Huntington, E H; Robilliard, C; Ralph, T C; Glöckl, O; Andersen, U L; Lorenz, S; Leuchs, G

    2005-01-01

    Quantum optics experiments on "bright" beams typically probe correlations between side-band modes. However the extra degree of freedom represented by this dual mode picture is generally ignored. We demonstrate the experimental operation of a device which can be used to separate the quantum side-bands of an optical field. We use this device to explicitly demonstrate the quantum entanglement between the side-bands of a squeezed beam.

  17. Design and analysis of microstrip photonic band gap filter without etching ground plane

    OpenAIRE

    R. N. Baral; P. K. Singhal

    2009-01-01

    A design of microstrip photonic band gap (PBG) filter is presented in this paper. The band reject filter is compact in structure and provides accurate band gap. The proposed filter has a periodic configuration; the impedance distribution over the length of each period is varied according to a designated sinusoidal function. Both theoretical and experimental results indicate that a bandstop filter with an extremely wide bandwidth can be achieved. Detailed analysis of the frequency response of ...

  18. Analysis of compressive failure of layered materials by kink band broadening

    DEFF Research Database (Denmark)

    Jensen, Henrik Myhre

    1999-01-01

    Failure by steady state kink band broadening in uni-directional fibre composites or layered materials is analysed. An incremental scheme for calculation of kink band broadening stresses and lock-up conditions in the band for arbitrary material behaviour is presented. The method is illustrated by...... material data which are representative for polymer matrix composites for which experimental work exists. (C) 1999 Elsevier Science Ltd. All rights reserved....

  19. Modeling charged defects inside density functional theory band gaps

    International Nuclear Information System (INIS)

    Density functional theory (DFT) has emerged as an important tool to probe microscopic behavior in materials. The fundamental band gap defines the energy scale for charge transition energy levels of point defects in ionic and covalent materials. The eigenvalue gap between occupied and unoccupied states in conventional DFT, the Kohn–Sham gap, is often half or less of the experimental band gap, seemingly precluding quantitative studies of charged defects. Applying explicit and rigorous control of charge boundary conditions in supercells, we find that calculations of defect energy levels derived from total energy differences give accurate predictions of charge transition energy levels in Si and GaAs, unhampered by a band gap problem. The GaAs system provides a good theoretical laboratory for investigating band gap effects in defect level calculations: depending on the functional and pseudopotential, the Kohn–Sham gap can be as large as 1.1 eV or as small as 0.1 eV. We find that the effective defect band gap, the computed range in defect levels, is mostly insensitive to the Kohn–Sham gap, demonstrating it is often possible to use conventional DFT for quantitative studies of defect chemistry governing interesting materials behavior in semiconductors and oxides despite a band gap problem

  20. Photonic band gaps with layer-by-layer double-etched structures

    International Nuclear Information System (INIS)

    Periodic layer-by-layer dielectric structures with full three-dimensional photonic band gaps have been designed and fabricated. In contrast to previous layer-by-layer structures the rods in each successive layer are at an angle of 70.5 degree to each other, achieved by etching both sides of a silicon wafer. Photonic band-structure calculations are utilized to optimize the photonic band gap by varying the structural geometry. The structure has been fabricated by double etching Si wafers producing millimeter wave photonic band gaps between 300 and 500 GHz, in excellent agreement with band calculations. Overetching this structure produces a multiply connected geometry and increases both the size and frequency of the photonic band gap, in very good agreement with experimental measurements. This new robust double-etched structure doubles the frequency possible from a single Si wafer, and can be scaled to produced band gaps at higher frequencies. copyright 1996 American Institute of Physics

  1. Design and analysis of defected ground structure transformer for dual-band antenna

    Directory of Open Access Journals (Sweden)

    Wai-Wa Choi

    2014-12-01

    Full Text Available This study presents a novel dual-band antenna design methodology utilising a dual-frequency impedance transformer with defected ground structure (DGS. The proposed dual-frequency DGS impedance transformer generates a second resonant frequency from a conventional single-band antenna, resulting dual-band operation. Simulation studies illustrate that the adopted design achieves versatile configurations for arbitrary operating frequencies and diverse input impedance ranges in planar antenna structures. To experimentally verify the proposed design methodology, a dual-frequency DGS impedance transformer was implemented for a 2.4 GHz monopole antenna to obtain a 900/2400 MHz dual-band antenna. Measurement shows that the 10 dB return loss bandwidth in 900 MHz band is 34.4 MHz, whereas that in 2400 MHz band is wider than 530 MHz. Typical monopole radiation patterns are observed at both operating bands.

  2. Comparison and fit of the two and six band k.p models for the band edge structure of Pbsub(1-x)Snsub(x)Te

    International Nuclear Information System (INIS)

    The band edge structure of Pbsub(1-x)Snsub(x)Te is derived in detail using a two band ellipsoidal model and compared with a more rigorous calculation based on six bands. A quantitative comparison is made for two values of the energy gap, corresponding to the cases where x=0 and x=0.17. It was found that, for the occupied states in nondegenerate materials, both models are practically equivalent. Discrepancies may occur only in high degeneracies or deep inversion layers. The agreement between both models was significantly improved by introducing an effective energy gap in the two band model. It is suggested that the use of the effective energy gap may improve the agreement between the two band model and experiment whenever the details of the band edge structure enter the interpretation of the experimental results. (author)

  3. Influence of Intermediate Principal Stress on Deformation Band Formation in Porous Sandstone

    Science.gov (United States)

    Issen, K. A.; Ingraham, M. D.; Dewers, T. A.

    2011-12-01

    In recent years, field observations of volumetric deformation bands (compaction bands and dilation bands) have prompted renewed laboratory and theoretical research efforts to understand conditions for deformation band formation. Historically, laboratory experiments have been conducted on cylindrical cores using axisymmetric stress states, where the intermediate principal stress is equal to either minimum or maximum compression. While experimentally convenient, it is not clear that these specialized stress states are common in field settings, where the intermediate principal stress likely falls between minimum and maximum compression. Additionally, theoretical predictions developed using a bifurcation approach to strain localization (Rudnicki and Rice, 1975) suggest that the deformation band type predicted to form (compaction, compactant shear, dilatant shear, dilation), and the orientation of the band relative to maximum compression, both depend on the magnitude of the intermediate principal stress relative to maximum and minimum compression. To examine the role of the intermediate principal stress in deformation band formation, a suite of true triaxial tests were conducted on Castlegate sandstone; this paper focuses on comparing theoretical predictions with experimental observations. Tests covered a wide range of mean stresses, from dilatant to compactant response. For a given mean stress, five stress states were tested, in which the intermediate principal stress was: A) equal to minimum compression, B) greater than the minimum but less than halfway to maximum compression, C) halfway between minimum and maximum compression, D) greater than halfway but less than maximum compression, and E) equal to maximum compression. Overall, reasonable agreement was found between predicted and observed band angles (defined as the angle between the band normal and maximum compression). Low mean stress tests produced the predicted high angles bands; at intermediate stresses

  4. Correlations in a band insulator

    Czech Academy of Sciences Publication Activity Database

    Sentef, M.; Kuneš, Jan; Werner, P.; Kampf, A. P.

    2009-01-01

    Roč. 80, č. 15 (2009), 155116/1-155116/7. ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : electronic correlations * dynamical mean-field theory * band insulator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.475, year: 2009

  5. Band structure and nuclear dynamics

    International Nuclear Information System (INIS)

    The relation between the Variable Moment of Inertia model and the Interacting Boson Model are discussed from a phenomenological viewpoint. New results on ground state mean-square radii in nuclei far from stability are reported, and a discussion of band structure extending to high angular momentum states and methods of extracting information on the underlying dynamics is given

  6. Metaphyseal bands in osteogenesis imperfecta

    International Nuclear Information System (INIS)

    An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as “zebra lines.”

  7. Tolerance bands for functional data.

    Science.gov (United States)

    Rathnayake, Lasitha N; Choudhary, Pankaj K

    2016-06-01

    Often the object of inference in biomedical applications is a range that brackets a given fraction of individual observations in a population. A classical estimate of this range for univariate measurements is a "tolerance interval." This article develops its natural extension for functional measurements, a "tolerance band," and proposes a methodology for constructing its pointwise and simultaneous versions that incorporates both sparse and dense functional data. Assuming that the measurements are observed with noise, the methodology uses functional principal component analysis in a mixed model framework to represent the measurements and employs bootstrapping to approximate the tolerance factors needed for the bands. The proposed bands also account for uncertainty in the principal components decomposition. Simulations show that the methodology has, generally, acceptable performance unless the data are quite sparse and unbalanced, in which case the bands may be somewhat liberal. The methodology is illustrated using two real datasets, a sparse dataset involving CD4 cell counts and a dense dataset involving core body temperatures. PMID:26574904

  8. A PHOTONIC BAND GAP FIBRE

    DEFF Research Database (Denmark)

    1999-01-01

    An optical fibre having a periodicidal cladding structure provididing a photonic band gap structure with superior qualities. The periodical structure being one wherein high index areas are defined and wherein these are separated using a number of methods. One such method is the introduction of...

  9. Band gap ion mass filter

    International Nuclear Information System (INIS)

    Ions in a plasma may be radially separated according to mass using a combination of an axial magnetic field and either a radial or azimuthal electric field. The separation is qualitatively different from that obtained by a plasma centrifuge and the characteristics of confined and unconfined ion orbits are analogous to the phenomenon of band gaps in semiconductors

  10. Broad-band transmission spectrum and K-band thermal emission of WASP-43b as observed from the ground

    CERN Document Server

    Chen, Guo; Wang, Hongchi; Nikolov, Nikolay; Fortney, Jonathan J; Seemann, Ulf; Wang, Wei; Mancini, Luigi; Henning, Thomas

    2014-01-01

    (Abridged) We observed one transit and one occultation of the hot Jupiter WASP-43b simultaneously in the g'r'i'z'JHK bands using the GROND instrument on the MPG/ESO 2.2-meter telescope. From the transit event, we have independently derived WASP-43's system parameters with high precision, and improved the period to be 0.81347437(13) days. No significant variation in transit depths is detected, with the largest deviations coming from the i', H, and K bands. Given the observational uncertainties, the broad-band transmission spectrum can be explained by either a flat featureless straight line that indicates thick clouds, synthetic spectra with absorption signatures of atomic Na/K or molecular TiO/VO that indicate cloud-free atmosphere, or a Rayleigh scattering profile that indicates high-altitude hazes. From the occultation event, we have detected planetary dayside thermal emission in the K-band with a flux ratio of 0.197 +/- 0.042%, which confirms previous detections obtained in the 2.09 micron narrow band and K...

  11. Optical band gaps of organic semiconductor materials

    Science.gov (United States)

    Costa, José C. S.; Taveira, Ricardo J. S.; Lima, Carlos F. R. A. C.; Mendes, Adélio; Santos, Luís M. N. B. F.

    2016-08-01

    UV-Vis can be used as an easy and forthright technique to accurately estimate the band gap energy of organic π-conjugated materials, widely used as thin films/composites in organic and hybrid electronic devices such as OLEDs, OPVs and OFETs. The electronic and optical properties, including HOMO-LUMO energy gaps of π-conjugated systems were evaluated by UV-Vis spectroscopy in CHCl3 solution for a large number of relevant π-conjugated systems: tris-8-hydroxyquinolinatos (Alq3, Gaq3, Inq3, Al(qNO2)3, Al(qCl)3, Al(qBr)3, In(qNO2)3, In(qCl)3 and In(qBr)3); triphenylamine derivatives (DDP, p-TTP, TPB, TPD, TDAB, m-MTDAB, NPB, α-NPD); oligoacenes (naphthalene, anthracene, tetracene and rubrene); oligothiophenes (α-2T, β-2T, α-3T, β-3T, α-4T and α-5T). Additionally, some electronic properties were also explored by quantum chemical calculations. The experimental UV-Vis data are in accordance with the DFT predictions and indicate that the band gap energies of the OSCs dissolved in CHCl3 solution are consistent with the values presented for thin films.

  12. Spectra of {gamma} rays feeding superdeformed bands

    Energy Technology Data Exchange (ETDEWEB)

    Lauritsen, T.; Khoo, T.L.; Henry, R.G. [and others

    1995-08-01

    The spectrum of {gamma}rays coincident with SD transitions contains the transitions which populate the SD band. This spectrum can provide information on the feeding mechanism and on the properties (moment of inertia, collectivity) of excited SD states. We used a model we developed to explain the feeding of SD bands, to calculate the spectrum of feeding {gamma}rays. The Monte Carlo simulations take into account the trigger conditions present in our Eurogam experiment. Both experimental and theoretical spectra contain a statistical component and a broad E2 peak (from transitions occurring between excited states in the SD well). There is good resemblance between the measured and calculated spectra although the calculated multiplicity of an E2 bump is low by {approximately}30%. Work is continuing to improve the quality of the fits, which will result in a better understanding of excited SD states. In addition, a model for the last steps, which cool the {gamma} cascade into the SD yrast line, needs to be developed. A strong M1/E2 low-energy component, which we believe is responsible for this cooling, was observed.

  13. Search for band termination in 121Xe

    International Nuclear Information System (INIS)

    Complete text of publication follows. The high-spin states of 121Xe have been studied, using the 64Ni(64Ni,α3n) nuclear reaction, in order to identify terminating bands in this nucleus. The EUROBALL γ-ray spectrometer and its ancillary charged-particle detector, DIAMANT, were used to collect gamma-particle coincidence events (for experimental details see Ref. [1]). The data were sorted into γγ- and γγγ-coincidence matrices by requiring the detection of one α particle. The level scheme of 121Xe, as shown in Fig. 1, was constructed using the triple-coincidence relations and the energy and intensity balances of the γ-ray transitions. The level spins and parities were deduced from transition multipolarities derived from measured DCO-ratios and linear polarisations. Most of the excited states known from previous studies were confirmed and some of the previously known bands have been extended to higher spins. Configuration-dependent cranked Nilsson- Strutinsky-type calculations were performed to help the interpretation of high-spin states observed in 121Xe and the identification of terminating states. This work is in progress

  14. Electronic structure, optical properties and Compton profiles of RuO{sub 2}: Performance of PBEsol exchange–correlation approximation

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Khushboo [Department of Physics, M.L. Sukhadia University, Udaipur 313002, Rajasthan (India); Sahariya, Jagrati [Department of Physics, Manipal University, Jaipur 303007, Rajasthan (India); Ahuja, B.L., E-mail: blahuja@yahoo.com [Department of Physics, M.L. Sukhadia University, Udaipur 313002, Rajasthan (India)

    2015-10-05

    Highlights: • First ever Compton study of rutile RuO{sub 2}. • Demonstrated use of new PBEsol potential for electronic properties using LCAO and FP-LAPW. • Analyzed optical and electronic structure calculations and compared with experiment. - Abstract: We present first ever electron momentum density of RuO{sub 2} using 20 Ci {sup 137}Cs (661.65 keV) Compton spectrometer at a resolution (Gaussian FWHM) of 0.34 a.u. The experimental Compton profile (CP) has been compared with the theoretical profiles computed using linear combination of atomic orbitals (LCAO) within framework Hartree–Fock scheme and of density functional theory. Comparison of theoretical and experimental CPs demonstrates usefulness of revised functional of Perdew–Burke–Ernzerhof (so called PBEsol) in computing the electronic properties of RuO{sub 2}. The energy bands and density of states of RuO{sub 2} are also reported using LCAO and full potential linearized augmented plane wave (FP-LAPW) method within PBEsol approximation. The complex dielectric functions computed using FP-LAPW method are explained in terms of transitions within energy bands. Our results for dielectric functions show a good agreement with the available experimental data and confirm the Drude like behavior of RuO{sub 2}. The Fermi surface structure and reflectivity spectra computed using FP-LAPW method are found to be in tune with the available measurements.

  15. Electronic structure, optical properties and Compton profiles of RuO2: Performance of PBEsol exchange–correlation approximation

    International Nuclear Information System (INIS)

    Highlights: • First ever Compton study of rutile RuO2. • Demonstrated use of new PBEsol potential for electronic properties using LCAO and FP-LAPW. • Analyzed optical and electronic structure calculations and compared with experiment. - Abstract: We present first ever electron momentum density of RuO2 using 20 Ci 137Cs (661.65 keV) Compton spectrometer at a resolution (Gaussian FWHM) of 0.34 a.u. The experimental Compton profile (CP) has been compared with the theoretical profiles computed using linear combination of atomic orbitals (LCAO) within framework Hartree–Fock scheme and of density functional theory. Comparison of theoretical and experimental CPs demonstrates usefulness of revised functional of Perdew–Burke–Ernzerhof (so called PBEsol) in computing the electronic properties of RuO2. The energy bands and density of states of RuO2 are also reported using LCAO and full potential linearized augmented plane wave (FP-LAPW) method within PBEsol approximation. The complex dielectric functions computed using FP-LAPW method are explained in terms of transitions within energy bands. Our results for dielectric functions show a good agreement with the available experimental data and confirm the Drude like behavior of RuO2. The Fermi surface structure and reflectivity spectra computed using FP-LAPW method are found to be in tune with the available measurements

  16. A Compact Dual Band Dielectric Resonator Antenna For Wireless Applications

    Directory of Open Access Journals (Sweden)

    A. Gharsallah

    2013-06-01

    Full Text Available This paper presents the design of a dual band rectangular Dielectric Resonator Antenna (DRAcoupled to narrow slot aperture that is fed by microstrip line. The fundamental TE111mode andhigher-order TE113mode are excited with their resonant frequencies respectively. Thesefrequencies can be controlled by changing the DRA dimensions. A dielectric resonator with highpermittivity is used to miniaturize the global structure. The proposed antenna is designed to havedual band operation suitable for both DCS (1710 - 1880 MHz and WLAN (2400 - 2484 MHzapplications. The return loss, radiation pattern and gain of the proposed antenna are evaluated.Reasonable agreement between simulation and experimental results is obtained.

  17. Wide-Band Multi-spectral Space for Color Representation

    Institute of Scientific and Technical Information of China (English)

    KONG Lingwang; ZHU Yuanhong; Kurt Muenger; ZHANG Xuliang

    2003-01-01

    This paper develops a wide-band multi-spectral space for color representation with Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matching method aims at improving the accuracy of color representation as well as reducing costs for processing and storing multi-spectral images. The results show that the space can present our experimental original spectral spaces (i. e. Munsell color matt and DIN-6164 color chips) with high efficiency, and that the spanning space with three eigenvectors can present the original space at more than 98%CSCR, and when 5 eigenvectors are used it can cover almost the whole original spaces.

  18. Amorphous Photonic Lattices: Band Gaps, Effective Mass and Suppressed Transport

    CERN Document Server

    Rechtsman, Mikael; Dreisow, Felix; Heinrich, Matthias; Keil, Robert; Nolte, Stefan; Segev, Mordechai

    2010-01-01

    We present, theoretically and experimentally, amorphous photonic lattices exhibiting a band-gap yet completely lacking Bragg diffraction: 2D waveguides distributed randomly according to a liquid-like model responsible for the absence of Bragg peaks as opposed to ordered lattices containing disorder, which always exhibit Bragg peaks. In amorphous lattices the bands are comprised of localized states, but we find that defect states residing in the gap are more localized than the Anderson localization length. Finally, we show how the concept of effective mass carries over to amorphous lattices.

  19. Study of multiphonon bands of 150Sm using IBM-1

    International Nuclear Information System (INIS)

    At present large amount of experimental data is available from the radioactive decay, coulomb excitation and reaction work for six quasi bands (up to higher spins) of 150Sm. It requires a detailed theoretical analysis for complete explanation of the observed collective properties. In the present work the IBM-1 is applied to lower and higher bands up to higher spins. A least square search for four IBM-1 parameters is carried out to fit the observed spectra. All levels with reliable spin assignment (Iπ ≤ 10+ are used as input for PHINT programme

  20. Optimal Designs of Ultra Wide-band Communication Antennas

    Institute of Scientific and Technical Information of China (English)

    JIYicai; LIUQizhong; HEXiulian; ZHANGHou

    2004-01-01

    A novel design approach combining the Hybrid genetic algorithm (HGA) with Method of moment (MoM) is investigated for the fast optimal design of ultra wide-band loaded wire antennas. A simple filtrating procedure is used to reduce the number of the loads and the components of the loading circuits, thus making the manufacture and experimental adjustment of the antennas easier, and the reliability of the antennas enhanced. The effectivity of the proposed procedure is demonstrated through its application to the optimal design of an ultra wide-band antenna.

  1. On band gap predictions for multiresonant metamaterials on plates.

    Science.gov (United States)

    Yoritomo, John Y; Weaver, Richard L; Roux, Philippe; Rupin, Matthieu; Williams, Earl G

    2016-03-01

    Recently wide frequency band gaps were observed in an experimental realization of a multiresonant metamaterial for Lamb waves propagating in thin plates. The band gaps rose from hybridization between the flexural plate (A0 Lamb waves) and longitudinal resonances in rods attached perpendicularly. Shortly thereafter a theory based on considering a one-dimensional periodic array of rods and the scattering matrix for a single rod successfully described the observations. This letter presents an alternative simpler theory, arguably accurate at high rod density, that treats the full two-dimensional array of rods and makes no assumption of periodicity. This theory also fits the measurements. PMID:27036264

  2. Infrared spectroscopy at high temperature : N2- and O2-broadening coefficients in the ν4 band of CH4

    Science.gov (United States)

    Fissiaux, Laurent; Populaire, Jean-Claude; Blanquet, Ghislain; Lepère, Muriel

    2015-11-01

    In the present work, we have developed a high-temperature absorption cell for infrared spectroscopy. This absorption cell can contain gases of the room temperature up to 650 K without temperature gradient. The construction of the cell and its technical features are described in detail in this paper. In order to demonstrate the feasibility and the interest of the cell, we have measured the N2-, O2- and air-broadening coefficients of, respectively, six and three absorption lines in the ν4 band of methane at four temperatures (350, 425, 500, 575 K). The measurements of these coefficients was realized with a tunable diode-laser spectrometer. The line parameters were obtained by fitting to the experimental profile the Voigt line shape and the Rautian and Galatry models taking into account the collisional narrowing. For these lines, the n parameter of the temperature dependence has been determined.

  3. Theoretical study of relative width of photonic band gap for the 3-D dielectric structure

    Indian Academy of Sciences (India)

    G K Johri; Akhilesh Tiwari; Saumya Saxena; Rajesh Sharma; Kuldeep Srivastava; Manoj Johri

    2002-03-01

    Calculations for the relative width (/0) as a function of refractive index and relative radius of the photonic band gap for the fcc closed packed 3-D dielectric microstructure are reported and comparison of experimental observations and theoretical predictions are given. This work is useful for the understanding of photonic crystals and occurrence of the photonic band gap.

  4. Synthesis and design of waveguide band-stop filters without out-of-band spurious responses for plasma diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Montejo-Garai, Jose R., E-mail: jr@etc.upm.es [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Leal-Sevillano, Carlos A. [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Ruiz-Cruz, Jorge A. [Escuela Politecnica Superior, Universidad Autonoma de Madrid, C/Fco. Tomas y Valiente 11, Madrid 28409 (Spain); Rebollar, Jesus M. [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Estrada, Teresa [T. Laboratorio Nacional de Fusion, Asociacion Euratom-CIEMAT, Madrid 28040 (Spain)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer A rigorous systematic design process based on circuit synthesis is proposed for band-stop filters. Black-Right-Pointing-Pointer The new compact E-plane waveguide structure reduces drastically the unwanted resonances in a very large pass band. Black-Right-Pointing-Pointer The manufacturing process together with the computation effort is significantly reduced. Black-Right-Pointing-Pointer Experimental results validate the state-of-art electrical responses. - Abstract: Band-stop or notch filters play a crucial role in plasma diagnosis systems to protect receivers from the stray radiation. In this work, a rigorous design process based on circuit synthesis in addition to an extremely compact E-plane waveguide structure is proposed for this kind of filters. On the one hand, the transfer function verifying the rejection specification is analytically obtained, fixing the minimum number of required cavities. On the other hand, a coupling structure that reduces drastically the unwanted resonances in filters with a very large pass band requirement, is presented. This coupling between the rejection cavities and the main rectangular waveguide has additional advantages; (a) unlike typical inductive irises, large coupling coefficients can be implemented (b) a pure E-plane configuration is achieved, which simplifies the manufacturing and also reduces significantly the computational effort. Experimental validation is demonstrated by two pseudo-elliptic fifth-order band-stop filters fabricated and measured in Ka and V bands. In both cases, the filters are free of spurious resonances in their total operation bands.

  5. Broad-band acoustic hyperbolic metamaterial

    CERN Document Server

    Shen, Chen; Sui, Ni; Wang, Wenqi; Cummer, Steven A; Jing, Yun

    2015-01-01

    Acoustic metamaterials (AMMs) are engineered materials, made from subwavelength structures, that exhibit useful or unusual constitutive properties. There has been intense research interest in AMMs since its first realization in 2000 by Liu et al. A number of functionalities and applications have been proposed and achieved using AMMs. Hyperbolic metamaterials are one of the most important types of metamaterials due to their extreme anisotropy and numerous possible applications, including negative refraction, backward waves, spatial filtering, and subwavelength imaging. Although the importance of acoustic hyperbolic metamaterials (AHMMs) as a tool for achieving full control of acoustic waves is substantial, the realization of a broad-band and truly hyperbolic AMM has not been reported so far. Here, we demonstrate the design and experimental characterization of a broadband AHMM that operates between 1.0 kHz and 2.5 kHz.

  6. Band-edge BCS–BEC crossover in a two-band superconductor: physical properties and detection parameters

    International Nuclear Information System (INIS)

    Superconductivity in iron-based magnesium diborides and other novel superconducting materials has a strong multi-band and multi-gap character. Recent experiments support the possibillity for a BCS–BEC crossover induced by strong-coupling and proximity of the chemical potential to the edge of one of the bands. Here we study the simplest theoretical model which accounts for the BCS–BEC crossover in a two-band superconductor, considering tunable interactions and tunable energy separations between the bands. Mean-field results for condensate fraction, correlation length, and superconducting gap are reported in typical crossover diagrams to locate the boundaries of the BCS, crossover and BEC regimes. When the superconducting gap is of the order of the local chemical potential, superconductivity is in the crossover regime of the BCS–BEC crossover and the Fermi surface of the small band is smeared by the gap opening. In this situation, small and large Cooper pairs coexist in the total condensate, which is the optimal condition for high-Tc superconductivity. The ratio between the gap and the Fermi energy in a given band results in the best detection parameter for experiments to locate the system in the BCS–BEC crossover. Using available experimental data, our analysis shows that iron-based superconductors have the partial condensate of the small Fermi surface in the crossover regime of the BCS–BEC crossover, supporting the recent ARPES findings. (paper)

  7. Near band edge anisotropic optical transitions in wide band gap semiconductor Cu2ZnSiS4

    Science.gov (United States)

    Levcenco, S.; Dumcenco, D.; Huang, Y. S.; Arushanov, E.; Tezlevan, V.; Tiong, K. K.; Du, C. H.

    2010-10-01

    In this study, anisotropic near band edge transitions of Cu2ZnSiS4 single crystals grown by chemical vapor transport were characterized by using polarization-dependent absorption, piezoreflectance (PzR) and surface photovoltage (SPV) spectroscopy techniques at room temperature. The measurements were carried out on the as grown basal plane with the normal along [2 1 0] and the axis c parallel to the long edge of the crystal platelet. Analysis of absorption and SPV spectra reveal indirect allowed transitions for the absorption edge of Cu2ZnSiS4. The estimated values of indirect band gap are 2.97 eV and 3.07 eV, respectively, for E ⊥c and E ∥c polarization configurations. The polarization-dependent PzR and SPV spectra in the vicinity of the direct band gap of Cu2ZnSiS4 reveal features E⊥ex and E∥ex at around 3.32 eV and 3.41 eV for E ⊥c and E ∥c polarizations, respectively. Both features E⊥ex and E∥ex are associated with the interband excitonic transitions at point Γ and can be explained by crystal-field splitting of valence band. Based on the experimental observations, a plausible band structure near band edge of Cu2ZnSiS4 is proposed.

  8. Deformation bands in porous sandstones their microstructure and petrophysical properties

    Energy Technology Data Exchange (ETDEWEB)

    Torabi, Anita

    2007-12-15

    Deformation bands are commonly thin tabular zones of crushed or reorganized grains that form in highly porous rocks and sediments. Unlike a fault, typically the slip is negligible in deformation bands. In this dissertation the microstructure and petrophysical properties of deformation bands have been investigated through microscopy and numerical analysis of experimental and natural examples. The experimental work consists of a series of ring-shear experiments performed on porous sand at 5 and 20 MPa normal stresses and followed by microscopic examination of thin sections from the sheared samples. The results of the ring-shear experiments and comparison of them to natural deformation bands reveals that burial depth (level of normal stress in the experiments) and the amount of shear displacement during deformation are the two significant factors influencing the mode in which grains break and the type of shear zone that forms. Two end-member types of experimental shear zones were identified: (a) Shear zones with diffuse boundaries, which formed at low levels of normal stress and/or shear displacement; and (b) Shear zones with sharp boundaries, which formed at higher levels of normal stress and/or shear displacement. Our interpretation is that with increasing burial depth (approximately more than one kilometer, simulated in the experiments by higher levels of normal stress), the predominant mode of grain fracturing changes from flaking to splitting; which facilitates the formation of sharp-boundary shear zones. This change to grain splitting increases the power law dimension of the grain size distribution (D is about 1.5 in sharp boundary shear zones). Based on our observations, initial grain size has no influence in the deformation behavior of the sand at 5 MPa normal stresses. A new type of cataclastic deformation band is described through outcrop and microscopic studies; here termed a 'slipped deformation band'. Whereas previously reported cataclastic

  9. Determination of Stoichiometry of Solutes in Molten Salt Solvents by Correlations of Relative Raman Band Intensities

    DEFF Research Database (Denmark)

    Boghosian, Soghomon; Berg, Rolf W.

    1999-01-01

    Raman spectroscopy has been used to determine the stoichiometry of solute complexes in molten salts at high temperatures under static equilibrium conditions, A simple formalism is derived for correlating relative Raman band intensities with stoichiometric coefficients. The experimental procedures...

  10. Experimental study of the profiles of the Hsub(β) and HeI 43D, 3F-23P spectral lines broadened by Stark or Stark-Zeeman effect

    International Nuclear Information System (INIS)

    The profiles of the Hsub(β) (lambda=4861.32A) and HeI(lambda=4471.48A and lambda=4470.04A) lines emitted during the recombination phase of pulsed plasmas confined by magnetic fields (02 molecular spectrum during the recombination phase; a very strong coupling between Stark effect and Zeeman effect: consequently, the components of the normal Zeeman effect are shifted as the electron density increases

  11. 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.......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....

  12. The effects of band exercise using proprioceptive neuromuscular facilitation on muscular strength in lower extremity

    OpenAIRE

    Rhyu, Hyun-seung; Kim, Su-Hyun; Park, Hye-Sang

    2015-01-01

    The purpose of this study was to examine whether a six-week elastic band exercise program using proprioceptive neuromuscular facilitation (PNF) can increase isotonic strength of abductor muscles in the lower extremity. Twenty-eight healthy students from S university were divided into an experimental group and control group. Each group was participated in pre and post-measurement in isotonic strength using an isotonic analyzer, En-treeM. Experimental group performed elastic band exercise using...

  13. High Power Combiner/Divider Design for Dual Band RF Power Amplifiers

    OpenAIRE

    Flattery, Kyle; Amin, Shoaib; Rönnow, Daniel; Mahamat, Yaya; Eroglu, Abdullah

    2015-01-01

    Design of low loss with an enhanced thermal profile power divider/combiner for high power dual-band Radio Frequency (RF) power amplifier applications is given. The practical implementation, low loss and substrate characteristics make this type of combiner ideal for high power microwave applications.  The combiner operational frequencies are chosen to operate at 900 MHz and 2.14 GHz, which are common frequencies for concurrent dual band RF power amplifiers. The analytical results are verified ...

  14. Estimating the vertical structure of intense Mediterranean precipitation using two X-band weather radar systems

    OpenAIRE

    Berne, A.D.; Delrieu, G.; Andrieu, H.

    2005-01-01

    The present study aims at a preliminary approach of multiradar compositing applied to the estimation of the vertical structure of precipitation¿an important issue for radar rainfall measurement and prediction. During the HYDROMET Integrated Radar Experiment (HIRE¿98), the vertical profile of reflectivity was measured, on the one hand, with an X-band vertically pointing radar system, and, on the other hand, with an X-band RHI scanning protocol radar. The analysis of the raw data highlights the...

  15. Linear methods in band theory

    DEFF Research Database (Denmark)

    Andersen, O. Krogh

    1975-01-01

    Two approximate methods for solving the band-structure problem in an efficient and physically transparent way are presented and discussed in detail. The variational principle for the one-electron Hamiltonian is used in both schemes, and the trial functions are linear combinations of energy......-independent augmented plane waves (APW) and muffin-tin orbitals (MTO), respectively. The secular equations are therefore eigenvalue equations, linear in energy. The trial functions are defined with respect to a muffin-tin (MT) potential and the energy bands depend on the potential in the spheres through potential...... parameters which describe the energy dependence of the logarithmic derivatives. Inside the spheres, the energy-independent APW is that linear combination of an exact solution, at the arbitrary but fixed energy Eν, and its energy derivative which matches continuously and differentiably onto the plane...

  16. Collective band properties in actinide nuclei well deformed

    International Nuclear Information System (INIS)

    In actinides, proton i13/2 orbitals and neutron j15/2 orbitals are both near Fermi surface. At a great rotation speed, driving and Coriolis forces change the surface forces, in particular, they lower pairing forces inside the nucleus. The use of Coulomb excitation with the help of heavy and very heavy projectiles such as 32S, 84Kr, 142Nd, 208Pb at 232Th together with the most recent techniques of spectroscopy allowed to populate yrast bands of 230Th, 232Th, 235U and 237Np nuclei up to high spin states and together the even-even nuclei states in different collective bands. Experimental results have been analyzed in the frame of the different current models. The low spin states of rotational bands have been reproduced in a previous calculation using the nucleon-nucleon effective interaction of Skyrme III

  17. Band Anticrossing in Dilute Germanium Carbides Using Hybrid Density Functionals

    Science.gov (United States)

    Stephenson, Chad A.; O'brien, William A.; Qi, Meng; Penninger, Michael; Schneider, William F.; Wistey, Mark A.

    2016-04-01

    Dilute germanium carbides (Ge1- x C x ) offer a direct bandgap for compact silicon photonics, but widely varying properties have been reported. This work reports improved band structure calculations for Ge1- x C x using ab initio simulations that employ the HSE06 exchange-correlation density functional. Contrary to Vegard's law, the conduction band minimum at Γ is consistently found to decrease with increasing C content, while L and X valleys change much more slowly. The calculated Ge bandgap is within 11% of experimental values. A decrease in energy at the Γ conduction band valley of (170 meV ± 50)/%C is predicted, leading to a direct bandgap for x > 0.008. These results indicate a promising material for Group IV lasers.

  18. Analytical band Monte Carlo analysis of electron transport in silicene

    Science.gov (United States)

    Yeoh, K. H.; Ong, D. S.; Ooi, C. H. Raymond; Yong, T. K.; Lim, S. K.

    2016-06-01

    An analytical band Monte Carlo (AMC) with linear energy band dispersion has been developed to study the electron transport in suspended silicene and silicene on aluminium oxide (Al2O3) substrate. We have calibrated our model against the full band Monte Carlo (FMC) results by matching the velocity-field curve. Using this model, we discover that the collective effects of charge impurity scattering and surface optical phonon scattering can degrade the electron mobility down to about 400 cm2 V‑1 s‑1 and thereafter it is less sensitive to the changes of charge impurity in the substrate and surface optical phonon. We also found that further reduction of mobility to ∼100 cm2 V‑1 s‑1 as experimentally demonstrated by Tao et al (2015 Nat. Nanotechnol. 10 227) can only be explained by the renormalization of Fermi velocity due to interaction with Al2O3 substrate.

  19. Bulk band structure of Bi2Te3

    DEFF Research Database (Denmark)

    Michiardi, Matteo; Aguilera, Irene; Bianchi, Marco;

    2014-01-01

    The bulk band structure of Bi2Te3 has been determined by angle-resolved photoemission spectroscopy and compared to first-principles calculations. We have performed calculations using the local density approximation (LDA) of density functional theory and the one-shot GW approximation within the all......-electron full-potential linearized augmented-plane-wave (FLAPW) formalism, fully taking into account spin-orbit coupling. Quasiparticle effects produce significant changes in the band structure of Bi2Te3 when compared to LDA. Experimental and calculated results are compared in the spectral regions where...... distinct differences between the LDA and GW results are present. Overall a superior agreement with GW is found, highlighting the importance of many-body effects in the band structure of this family of topological insulators....

  20. Continuously Controlled Optical Band Gap in Oxide Semiconductor Thin Films.

    Science.gov (United States)

    Herklotz, Andreas; Rus, Stefania Florina; Ward, Thomas Zac

    2016-03-01

    The optical band gap of the prototypical semiconducting oxide SnO2 is shown to be continuously controlled through single axis lattice expansion of nanometric films induced by low-energy helium implantation. While traditional epitaxy-induced strain results in Poisson driven multidirectional lattice changes shown to only allow discrete increases in bandgap, we find that a downward shift in the band gap can be linearly dictated as a function of out-of-plane lattice expansion. Our experimental observations closely match density functional theory that demonstrates that uniaxial strain provides a fundamentally different effect on the band structure than traditional epitaxy-induced multiaxes strain effects. Charge density calculations further support these findings and provide evidence that uniaxial strain can be used to drive orbital hybridization inaccessible with traditional strain engineering techniques. PMID:26836282