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Sample records for absorption characterization descriptive

  1. Atomic absorption instrument functional description

    International Nuclear Information System (INIS)

    Bystroff, R.I.; Boyle, W.G. Jr.; Barton, G.W. Jr.

    1976-01-01

    This report describes a proposed system for automating atomic absorption analysis. The system consists of two atomic absorption instruments and an automatic sampler that can be attached to either instrument. A computer program controls the sampling and gathers data. The program then uses the data to perform bookkeeping, data processing, and report writing

  2. A microscopic description of sound absorption in the atmosphere

    Science.gov (United States)

    Bass, H. E.

    1976-01-01

    The various mechanisms which contribute to sound absorption in the atmosphere are identified and a technique for computing the contribution from each is presented. The similarities between sound absorption, laser fluorescence measurements, and the opto-acoustic effect are discussed. Finally, experimental sound absorption results are compared to predictions to test the microscopic energy transfer approach.

  3. A proposed descriptive methodology for environmental geologic (envirogeologic) site characterization

    International Nuclear Information System (INIS)

    Schwarz, D.L.; Snyder, W.S.

    1994-01-01

    We propose a descriptive methodology for use in environmental geologic (envirogeologic) site characterization. The method uses traditional sedimentologic descriptions augmented by environmental data needs, and facies analysis. Most other environmental methodologies for soil and sediment characterization use soil engineering and engineering geology techniques that classify by texture and engineering properties. This technique is inadequate for envirogeologic characterization of sediments. In part, this inadequacy is due to differences in the grain-size between the Unified soil Classification and the Udden-Wentworth scales. Use of the soil grain-size classification could easily cause confusion when attempting to relate descriptions based on this classification to our basic understanding of sedimentary depositional systems. The proposed envirogeologic method uses descriptive parameters to characterize a sediment sample, suggests specific tests on samples for adequate characterization, and provides a guidelines for subsurface facies analysis, based on data retrieved from shallow boreholes, that will allow better predictive models to be developed. This methodology should allow for both a more complete site assessment, and provide sufficient data for selection of the appropriate remediation technology, including bioremediation. 50 refs

  4. Description and characterization of HBWR Series H-1 test rods

    International Nuclear Information System (INIS)

    Wagoner, S.R.; Barner, J.O.; Welty, R.K.

    1979-06-01

    The as-built characterization results are presented for the HBWR Series H-1 test rods to be irradiated as part of the Fuel Performance Improvement Program (FPIP). The irradiation of these rods is to be conducted in the Halden Boiling Water Reactor (HBWR). Series H-1 consists of twelve rods for irradiation and six spares. Rod design types include (1) a reference dished pellet design, (2) an annular pellet design, (3) an annular pellet design combined with graphite-coated cladding, and (4) a packed-particle (vipac) design. The report, which describes the fabrication and detailed characterization results for the rods, is divided into four major sections: (1) experiment description, (2) process development required to fabricate the test rods, (3) methods and procedures used to fabricate and characterize the rods, and (4) a summary of the characterization results

  5. Characterization of cryogenic materials by x-ray absorption methods

    International Nuclear Information System (INIS)

    Heald, S.M.; Tranquada, J.M.

    1985-01-01

    X-ray absorption techniques have in recent years been developed into powerful probes of the electronic and structural properties of materials difficult to study by other techniques. In particular, the extended x-ray absorption fine structure (EXAFS) technique can be applied to a variety of cryogenic materials. Three examples are used to demonstrate the power of the technique. The first is the determination of the lattice location of dilute alloying additions such as Ta and Zr in Nb 3 Sn. The Ta additions are shown to reside predominately in Nb lattice sites, while Zr is not uniquely located at either Nb or Sn sites. In addition to structural information, temperature dependent EXAFS studies can be used to determine the rms deviations of atomic bond lengths, providing information about the temperature dependence of interatomic force constants. For Nb 3 Sn deviations are found from simple harmonic behavior at low temperatures which indicate a softening of the Nb-Sn bond strength. The final example is the study of interfacial properties in thin film systems. This is accomplished by making x-ray absorption measurements under conditions of total external reflection of the incident x-rays. As some examples show, this technique has great potential for studying interfacial reactions, a process used in the fabrication of many superconducting materials

  6. Precision atomic beam density characterization by diode laser absorption spectroscopy

    International Nuclear Information System (INIS)

    Oxley, Paul; Wihbey, Joseph

    2016-01-01

    We provide experimental and theoretical details of a simple technique to determine absolute line-of-sight integrated atomic beam densities based on resonant laser absorption. In our experiments, a thermal lithium beam is chopped on and off while the frequency of a laser crossing the beam at right angles is scanned slowly across the resonance transition. A lock-in amplifier detects the laser absorption signal at the chop frequency from which the atomic density is determined. The accuracy of our experimental method is confirmed using the related technique of wavelength modulation spectroscopy. For beams which absorb of order 1% of the incident laser light, our measurements allow the beam density to be determined to an accuracy better than 5% and with a precision of 3% on a time scale of order 1 s. Fractional absorptions of order 10 −5 are detectable on a one-minute time scale when we employ a double laser beam technique which limits laser intensity noise. For a lithium beam with a thickness of 9 mm, we have measured atomic densities as low as 5 × 10 4 atoms cm −3 . The simplicity of our technique and the details we provide should allow our method to be easily implemented in most atomic or molecular beam apparatuses.

  7. Precision atomic beam density characterization by diode laser absorption spectroscopy.

    Science.gov (United States)

    Oxley, Paul; Wihbey, Joseph

    2016-09-01

    We provide experimental and theoretical details of a simple technique to determine absolute line-of-sight integrated atomic beam densities based on resonant laser absorption. In our experiments, a thermal lithium beam is chopped on and off while the frequency of a laser crossing the beam at right angles is scanned slowly across the resonance transition. A lock-in amplifier detects the laser absorption signal at the chop frequency from which the atomic density is determined. The accuracy of our experimental method is confirmed using the related technique of wavelength modulation spectroscopy. For beams which absorb of order 1% of the incident laser light, our measurements allow the beam density to be determined to an accuracy better than 5% and with a precision of 3% on a time scale of order 1 s. Fractional absorptions of order 10 -5 are detectable on a one-minute time scale when we employ a double laser beam technique which limits laser intensity noise. For a lithium beam with a thickness of 9 mm, we have measured atomic densities as low as 5 × 10 4 atoms cm -3 . The simplicity of our technique and the details we provide should allow our method to be easily implemented in most atomic or molecular beam apparatuses.

  8. Quartz crystal microbalance and infrared reflection absorption spectroscopy characterization of bisphenol A absorption in the poly(acrylate) thin films.

    Science.gov (United States)

    Li, Guifeng; Morita, Shigeaki; Ye, Shen; Tanaka, Masaru; Osawa, Masatoshi

    2004-02-01

    The absorption process of bisphenol A (BPA) in a number of poly(acrylate) thin films, such as poly(2-methoxyethyl acrylate) (PMEA), poly(ethyl acrylate) (PEA), poly(n-butyl methacrylate) (PBMA), and poly(methyl methacrylate) (PMMA), has been investigated by quartz crystal microbalance (QCM) and infrared reflection absorption spectroscopy (IRRAS) measurements. Both QCM and IRRAS measurements show that the BPA molecules absorb in PMEA, PEA, and PBMA thin films but not in PMMA thin film. The differences in the BPA absorption behavior are mainly attributed to the difference in the glass transition temperature (T(g)) between these polymers. This absorption behavior also depends on the BPA concentration and polymer film thickness. Furthermore, IRRAS characterization demonstrates that the hydrogen bonding is formed between the hydroxyl group in BPA and the carbonyl group in the poly(acrylate) thin films. BPA molecule absorbed in these polymer thin films can be removed by ethanol rinse treatment. By optimizing experimental conditions for the QCM electrode modified by PMEA thin film, detection limitation of approximately 1 ppb for BPA can be realized by the in situ QCM measurement. This method is expected to be a sensitive in situ detection way for trace BPA in the environmental study.

  9. DUVAS (derivative uv-absorption spectrometer): instrument description and operating manual

    International Nuclear Information System (INIS)

    Hawthorne, A.R.; Dougherty, J.M.; Metcalfe, C.E.

    1980-11-01

    DUVAS is a real-time, field-portable spectrometer capable of monitoring a variety of aromatic organic vapors and inorganic gases at sub-ppM concentrations. The instrument is a prototype, microcomputer-controlled, derivative ultraviolet (UV) absorption spectrometer (DUVAS) developed primarily for area monitoring at coal conversion facilities, although other important occupational and environmental monitoring applications for compounds such as SO 2 , NO/sub x/, NH 3 , and HCHO are also being pursued

  10. DUVAS (derivative uv-absorption spectrometer): instrument description and operating manual

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, A.R.; Dougherty, J.M.; Metcalfe, C.E.

    1980-11-01

    DUVAS is a real-time, field-portable spectrometer capable of monitoring a variety of aromatic organic vapors and inorganic gases at sub-ppM concentrations. The instrument is a prototype, microcomputer-controlled, derivative ultraviolet (UV) absorption spectrometer (DUVAS) developed primarily for area monitoring at coal conversion facilities, although other important occupational and environmental monitoring applications for compounds such as SO/sub 2/, NO/sub x/, NH/sub 3/, and HCHO are also being pursued.

  11. Characterization of Spectral Absorption Properties of Aerosols Using Satellite Observations

    Science.gov (United States)

    Torres, O.; Jethva, H.; Bhartia, P. K.; Ahn, C.

    2012-01-01

    The wavelength-dependence of aerosol absorption optical depth (AAOD) is generally represented in terms of the Angstrom Absorption Exponent (AAE), a parameter that describes the dependence of AAOD with wavelength. The AAE parameter is closely related to aerosol composition. Black carbon (BC) containing aerosols yield AAE values near unity whereas Organic carbon (OC) aerosol particles are associated with values larger than 2. Even larger AAE values have been reported for desert dust aerosol particles. Knowledge of spectral AAOD is necessary for the calculation of direct radiative forcing effect of aerosols and for inferring aerosol composition. We have developed a satellitebased method of determining the spectral AAOD of absorbing aerosols. The technique uses high spectral resolution measurements of upwelling radiation from scenes where absorbing aerosols lie above clouds as indicated by the UV Aerosol Index. For those conditions, the satellite measured reflectance (rho lambda) is approximately given by Beer's law rho lambda = rho (sub 0 lambda) e (exp -mtau (sub abs lambda)) where rho(sub 0 lambda) is the cloud reflectance, m is the geometric slant path and tau (sub abs lambda) is the spectral AAOD. The rho (sub 0 lambda) term is determined by means of radiative transfer calculations using as input the cloud optical depth derived as described in Torres et al. [JAS, 2012] that accounts for the effects of aerosol absorption. In the second step, corrections for molecular and aerosol scattering effects are applied to the cloud reflectance term, and the spectral AAOD is then derived by inverting the equation above. The proposed technique will be discussed in detail and application results will be presented. The technique can be easily applied to hyper-spectral satellite measurements that include UV such as OMI, GOME and SCIAMACHY, or to multi-spectral visible measurements by other sensors provided that the aerosol-above-cloud events are easily identified.

  12. Doppler-broadened NICE-OHMS beyond the cavity-limited weak absorption condition - I. Theoretical description

    Science.gov (United States)

    Ma, Weiguang; Silander, Isak; Hausmaninger, Thomas; Axner, Ove

    2016-01-01

    Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is conventionally described by an expression (here referred to as the CONV expression) that is restricted to the case when the single-pass absorbance, α0L, is much smaller than the empty cavity losses, π/F [here termed the conventional cavity-limited weak absorption (CCLWA) condition]. This limits the applicability of the technique, primarily its dynamic range and calibration capability. To remedy this, this work derives extended descriptions of Db NICE-OHMS that are not restricted to the CCLWA condition. First, the general principles of Db NICE-OHMS are scrutinized in some detail. Based solely upon a set of general assumptions, predominantly that it is appropriate to linearize the Beer-Lambert law, that the light is modulated to a triplet, and that the Pound-Drever-Hall sidebands are fully reflected, a general description of Db NICE-OHMS that is not limited to any specific restriction on α0L vs. π/F, here referred to as the FULL description, is derived. However, this description constitutes a set of equations to which no closed form solution has been found. Hence, it needs to be solved numerically (by iterations), which is inconvenient. To circumvent this, for the cases when α0L<π/F but without the requirement that the stronger CCLWA condition needs to be fulfilled, a couple of simplified extended expressions that are expressible in closed analytical form, referred to as the extended locking and extended transmission description, ELET, and the extended locking and full transmission description, ELFT, have been derived. An analysis based on simulations validates the various descriptions and assesses to which extent they agree. It is shown that in the CCLWA limit, all extended descriptions revert to the CONV expression. The latter one deviates though from the extended ones for α0L around and above 0.1π/F. The two simplified extended descriptions agree

  13. Nanofluid optical property characterization: towards efficient direct absorption solar collectors

    Directory of Open Access Journals (Sweden)

    Otanicar Todd

    2011-01-01

    Full Text Available Abstract Suspensions of nanoparticles (i.e., particles with diameters < 100 nm in liquids, termed nanofluids, show remarkable thermal and optical property changes from the base liquid at low particle loadings. Recent studies also indicate that selected nanofluids may improve the efficiency of direct absorption solar thermal collectors. To determine the effectiveness of nanofluids in solar applications, their ability to convert light energy to thermal energy must be known. That is, their absorption of the solar spectrum must be established. Accordingly, this study compares model predictions to spectroscopic measurements of extinction coefficients over wavelengths that are important for solar energy (0.25 to 2.5 μm. A simple addition of the base fluid and nanoparticle extinction coefficients is applied as an approximation of the effective nanofluid extinction coefficient. Comparisons with measured extinction coefficients reveal that the approximation works well with water-based nanofluids containing graphite nanoparticles but less well with metallic nanoparticles and/or oil-based fluids. For the materials used in this study, over 95% of incoming sunlight can be absorbed (in a nanofluid thickness ≥10 cm with extremely low nanoparticle volume fractions - less than 1 × 10-5, or 10 parts per million. Thus, nanofluids could be used to absorb sunlight with a negligible amount of viscosity and/or density (read: pumping power increase.

  14. A microscopic description of absorption in high-energy string-brane collisions

    CERN Document Server

    D'Appollonio, Giuseppe; Russo, Rodolfo; Veneziano, Gabriele

    2016-01-01

    We study the collision of a highly energetic light closed string off a stack of Dp-branes at (sub)string-scale impact parameters and in a regime justifying a perturbative treatment. Unlike at larger impact parameters - where elastic scattering and/or tidal excitations dominate - here absorption of the closed string by the brane system, with the associated excitation of open strings living on it, becomes important. As a first step, we study this phenomenon at the disk level, in which the energetic closed string turns into a single heavy open string at rest whose particularly simple properties are described.

  15. A microscopic description of absorption in high-energy string-brane collisions

    Energy Technology Data Exchange (ETDEWEB)

    D’Appollonio, Giuseppe [Dipartimento di Fisica, Università di Cagliari and INFNCittadella Universitaria, 09042 Monserrato (Italy); Vecchia, Paolo Di [The Niels Bohr Institute, University of Copenhagen,Blegdamsvej 17, DK-2100 Copenhagen Ø (Denmark); Nordita, KTH Royal Institute of Technology and Stockholm University,Roslagstullsbacken 23, SE-10691 Stockholm (Sweden); Russo, Rodolfo [Queen Mary University of London,Mile End Road, E1 4NS London (United Kingdom); Veneziano, Gabriele [Collège de France,11 place M. Berthelot, 75005 Paris (France); Theory Division, CERN,CH-1211 Geneva 23 (Switzerland)

    2016-03-07

    We study the collision of a highly energetic light closed string off a stack of Dp-branes at (sub)string-scale impact parameters and in a regime justifying a perturbative treatment. Unlike at larger impact parameters — where elastic scattering and/or tidal excitations dominate — here absorption of the closed string by the brane system, with the associated excitation of open strings living on it, becomes important. As a first step, we study this phenomenon at the disk level, in which the energetic closed string turns into a single heavy open string at rest whose particularly simple properties are described.

  16. Characterization of the oral absorption of several aminopenicillins: determination of intrinsic membrane absorption parameters in the rat intestine in situ

    Science.gov (United States)

    Sinko, P. J.; Amidon, G. L.

    1992-01-01

    The absorption mechanism of several penicillins was characterized using in situ single-pass intestinal perfusion in the rat. The intrinsic membrane parameters were determined using a modified boundary layer model (fitted value +/- S.E.): Jmax* = 11.78 +/- 1.88 mM, Km = 15.80 +/- 2.92 mM, Pm* = 0, Pc* = 0.75 +/- 0.04 for ampicillin; Jmax* = 0.044 +/- 0.018 mM, Km = 0.058 +/- 0.026 mM, Pm* = 0.558 +/- 0.051, Pc* = 0.757 +/- 0.088 for amoxicillin; and Jmax* = 16.30 +/- 3.40 mM, Km = 14.00 +/- 3.30 mM, Pm* = 0, Pc* = 1.14 +/- 0.05 for cyclacillin. All of the aminopenicillins studied demonstrated saturable absorption kinetics as indicated by their concentration-dependent wall permeabilities. Inhibition studies were performed to confirm the existence of a nonpassive absorption mechanism. The intrinsic wall permeability (Pw*) of 0.01 mM ampicillin was significantly lowered by 1 mM amoxicillin and the Pw* of 0.01 mM amoxicillin was reduced by 2 mM cephradine consistent with competitive inhibition.

  17. X-ray absorption in characterization of laser fusion targets

    International Nuclear Information System (INIS)

    Clement, X.; Coudeville, A.; Eyharts, P.; Perrine, J.P.; Rouillard, R.

    1982-11-01

    Many plastic or metal coated targets are opaque, so their thickness and thickness uniformity cannot be obtained by optical means. Therefore, we have built and tested a new system using monochromatic X-ray absorption measurements. This system is also able to perform non-destructive measurements of argon fill pressure in glass microballoons. The X-ray source is a diffraction tube with a chromium target and fine focus (0.4 x 0.8 mm 2 ). Since monochromatic calculations are involved in this method, we use electronic discrimination to isolate the chromium Kα line (5.4 keV) from the bremsstrahlung spectrum. The detectors are xenon-filled proportional counters. The system is composed of two beams (10 μm in diameter), one used as a reference and the other as the measurement arm. A PET desk computer is coupled ot the experiment. We achieved a precision better than 10% for gold layers in the range of 0.1 to 1 μm, and better than 20% for argon pressures in the range of 5 - 13 bars

  18. Synergic use of TOMS and AERONET observations for characterization of aerosol absorption

    Science.gov (United States)

    Torres, O.; Sinyuk, A.; Bhartia, P. K.; Dubovik, O.; Holben, B.

    2003-04-01

    The role of aerosol absorption on the radiative transfer balance of the earth-atmosphere system is one of the largest sources of uncertainty in the analysis of global climate change. Global measurements of aerosol single scattering albedo are, therefore, necessary to properly assess the radiative forcing effect of aerosols. Remote sensing of aerosol absorption is currently carried out using both ground (Aerosol Robotic Network) and space (Total Ozone Mapping Spectrometer) based observations. The satellite technique uses measurements of backscattered near ultraviolet radiation. Carbonaceous aerosols, resulting from the combustion of biomass, are one of the most predominant absorbing aerosol types in the atmosphere. In this presentation, TOMS and AERONET retrievals of single scattering albedo of carbonaceous aerosols, are compared for different environmental conditions: agriculture related biomass burning in South America and Africa and peat fires in Eastern Europe. The AERONET and TOMS derived aerosol absorption information are in good quantitative agreement. The most absorbing smoke is detected over the African Savanna. Aerosol absorption over the Brazilian rain forest is less absorbing. Absorption by aerosol particles resulting from peat fires in Eastern Europe is weaker than the absorption measured in Africa and South America. This analysis shows that the near UV satellite method of aerosol absorption characterization has the sensitivity to distinguish different levels of aerosol absorption. The analysis of the combined AERONET-TOMS observations shows a high degree of synergy between satellite and ground based observations.

  19. Computer systems and software description for gas characterization system

    International Nuclear Information System (INIS)

    Vo, C.V.

    1997-01-01

    The Gas Characterization System Project was commissioned by TWRS management with funding from TWRS Safety, on December 1, 1994. The project objective is to establish an instrumentation system to measure flammable gas concentrations in the vapor space of selected watch list tanks, starting with tank AN-105 and AW-101. Data collected by this system is meant to support first tank characterization, then tank safety. System design is premised upon Characterization rather than mitigation, therefore redundancy is not required

  20. Optical absorption and emission characterization of P3HT: graphene composite for its prospective photovoltaic application

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Joginder, E-mail: jsdevgan.singh@gmail.com; Prasad, Neetu; Nirwal, Varun Singh; Gautam, Khyati; Peta, Koteswara Rao; Bhatnagar, P. K. [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi, India-110021 (India)

    2016-05-23

    In the present work, regioregular P3HT (Poly (3-hexylthiophene-2, 5-diyl) was blended with graphene nanopowder and the optical spectroscopic characterization of the composite has been performed. It was observed that at low concentration of graphene (up to 0.1 wt %) there is no significant variation in absorption intensity or wavelength range. But at higher concentration (> 0.1 wt %) the absorption intensity starts reducing. Whereas, the photoluminescence of the composite solution quenches as we increase the concentration of graphene. It reveals that charge recombination decreases with increase in concentration (0.05 to 0.5 wt %) of graphene. Therefore 0.1 wt % seems to be the optimized concentration of graphene in the composite for which appropriate quenching of PL was observed without any significant reduction in absorption of photons. Thus maximum efficiency in P3HT: graphene composite photovoltaic cell is expected for 0.1 wt % of graphene concentration in our typical case.

  1. Optical absorption and emission characterization of P3HT: graphene composite for its prospective photovoltaic application

    International Nuclear Information System (INIS)

    Singh, Joginder; Prasad, Neetu; Nirwal, Varun Singh; Gautam, Khyati; Peta, Koteswara Rao; Bhatnagar, P. K.

    2016-01-01

    In the present work, regioregular P3HT (Poly (3-hexylthiophene-2, 5-diyl) was blended with graphene nanopowder and the optical spectroscopic characterization of the composite has been performed. It was observed that at low concentration of graphene (up to 0.1 wt %) there is no significant variation in absorption intensity or wavelength range. But at higher concentration (> 0.1 wt %) the absorption intensity starts reducing. Whereas, the photoluminescence of the composite solution quenches as we increase the concentration of graphene. It reveals that charge recombination decreases with increase in concentration (0.05 to 0.5 wt %) of graphene. Therefore 0.1 wt % seems to be the optimized concentration of graphene in the composite for which appropriate quenching of PL was observed without any significant reduction in absorption of photons. Thus maximum efficiency in P3HT: graphene composite photovoltaic cell is expected for 0.1 wt % of graphene concentration in our typical case.

  2. Characterizing the Absorption Properties for Remote Sensing of Three Small Optically-Diverse South African Reservoirs

    Directory of Open Access Journals (Sweden)

    Mark William Matthews

    2013-09-01

    Full Text Available Characterizing the specific inherent optical properties (SIOPs of water constituents is fundamental to remote sensing applications. Therefore, this paper presents the absorption properties of phytoplankton, gelbstoff and tripton for three small, optically-diverse South African inland waters. The three reservoirs,  Hartbeespoort, Loskop and Theewaterskloof, are challenging for remote sensing, due to differences in phytoplankton assemblage and the considerable range of constituent concentrations. Relationships between the absorption properties and biogeophysical parameters, chlorophyll-a (chl-a, TChl (chl-a plus  phaeopigments,  seston,  minerals  and  tripton, are established. The value determined for the mass-specific tripton absorption coefficient at 442 nm, a∗ (442, ranges from 0.024 to 0.263 m2·g−1. The value of the TChl-specific phytoplankton absorption coefficient (a∗ was strongly influenced by phytoplankton species, size, accessory pigmentation and biomass. a∗ (440 ranged from 0.056 to 0.018 m2·mg−1 in oligotrophic to hypertrophic waters. The positive relationship between cell size and trophic state observed in open ocean waters was violated by significant small cyanobacterial populations. The phycocyanin-specific phytoplankton  absorption  at  620  nm,  a∗ (620, was determined as 0.007 m2·g−1 in a M. aeruginosa bloom. Chl-a was a better indicator of phytoplankton biomass than phycocyanin (PC in surface scums, due to reduced accessory pigment production. Absorption budgets demonstrate that monospecific blooms of M. aeruginosa and C. hirundinella may be treated as “cultures”, removing some complexities for remote sensing applications.   These results contribute toward a better understanding of IOPs and remote sensing applications in hypertrophic inland waters. However, the majority of the water is optically complex, requiring the usage of all the SIOPs derived here for remote sensing applications. The

  3. Characterization of a new modular decay total absorption gamma-ray spectrometer (DTAS) for FAIR

    International Nuclear Information System (INIS)

    Montaner Pizá, A.; Taín, J. L.; Agramunt, J.; Algora, A.; Guadilla, V.; Marín, E.; Rice, S.; Rubio, B.

    2013-01-01

    Beta-decay studies are one of the main goals of the DEcay SPECtroscopy experiment (DESPEC) to be installed at the future Facility for Antiproton and Ion Research (FAIR). DESPEC aims at the study of nuclear structure of exotic nuclei. A new modular Decay Total Absorption gamma-ray Spectrometer (DTAS) is being built at IFIC and is specially adapted to studies at fragmentation facilities such as the Super Fragment Separator (Super-FRS) at FAIR. The designed spectrometer is composed of 16 identical NaI(Tl) scintillation crystals. This work focuses on the characterization of these independent modules, as an initial step for the characterization of the full spectrometer. Monte Carlo simulations have been performed in order to understand the detector response.

  4. Characterization of a new modular decay total absorption gamma-ray spectrometer (DTAS) for FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Montaner Piza, A.; Tain, J. L.; Agramunt, J.; Algora, A.; Guadilla, V.; Marin, E.; Rice, S.; Rubio, B. [Instituto de Fisica Corpuscular, CSIC-Univ. de Valencia, Apdo. Correos 22085, E-46071 Valencia (Spain)

    2013-06-10

    Beta-decay studies are one of the main goals of the DEcay SPECtroscopy experiment (DESPEC) to be installed at the future Facility for Antiproton and Ion Research (FAIR). DESPEC aims at the study of nuclear structure of exotic nuclei. A new modular Decay Total Absorption gamma-ray Spectrometer (DTAS) is being built at IFIC and is specially adapted to studies at fragmentation facilities such as the Super Fragment Separator (Super-FRS) at FAIR. The designed spectrometer is composed of 16 identical NaI(Tl) scintillation crystals. This work focuses on the characterization of these independent modules, as an initial step for the characterization of the full spectrometer. Monte Carlo simulations have been performed in order to understand the detector response.

  5. Characterization of a new modular decay total absorption gamma-ray spectrometer (DTAS) for FAIR

    Science.gov (United States)

    Pizá, A. Montaner; Taín, J. L.; Agramunt, J.; Algora, A.; Guadilla, V.; Marín, E.; Rice, S.; Rubio, B.

    2013-06-01

    Beta-decay studies are one of the main goals of the DEcay SPECtroscopy experiment (DESPEC) to be installed at the future Facility for Antiproton and Ion Research (FAIR). DESPEC aims at the study of nuclear structure of exotic nuclei. A new modular Decay Total Absorption gamma-ray Spectrometer (DTAS) is being built at IFIC and is specially adapted to studies at fragmentation facilities such as the Super Fragment Separator (Super-FRS) at FAIR. The designed spectrometer is composed of 16 identical NaI(Tl) scintillation crystals. This work focuses on the characterization of these independent modules, as an initial step for the characterization of the full spectrometer. Monte Carlo simulations have been performed in order to understand the detector response.

  6. Empirical model description of photon path length for differential path length spectroscopy: combined effect of scattering and absorption

    NARCIS (Netherlands)

    Kanick, Stephen C.; Sterenborg, Henricus J. C. M.; Amelink, Arjen

    2008-01-01

    Differential path length spectroscopy (DPS) is a method of reflectance spectroscopy that utilizes a specialized fiber geometry to make the photon path length (tau) insensitive to variations in tissue optical properties over a wide range of absorption (mu(a)) and total scattering (mu(s))

  7. X-ray Absorption Spectroscopy Characterization of Electrochemical Processes in Renewable Energy Storage and Conversion Devices

    Energy Technology Data Exchange (ETDEWEB)

    Farmand, Maryam [George Washington Univ., Washington, DC (United States)

    2013-05-19

    The development of better energy conversion and storage devices, such as fuel cells and batteries, is crucial for reduction of our global carbon footprint and improving the quality of the air we breathe. However, both of these technologies face important challenges. The development of lower cost and better electrode materials, which are more durable and allow more control over the electrochemical reactions occurring at the electrode/electrolyte interface, is perhaps most important for meeting these challenges. Hence, full characterization of the electrochemical processes that occur at the electrodes is vital for intelligent design of more energy efficient electrodes. X-ray absorption spectroscopy (XAS) is a short-range order, element specific technique that can be utilized to probe the processes occurring at operating electrode surfaces, as well for studying the amorphous materials and nano-particles making up the electrodes. It has been increasingly used in recent years to study fuel cell catalysts through application of the and #916; and mgr; XANES technique, in combination with the more traditional X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) techniques. The and #916; and mgr; XANES data analysis technique, previously developed and applied to heterogeneous catalysts and fuel cell electrocatalysts by the GWU group, was extended in this work to provide for the first time space resolved adsorbate coverages on both electrodes of a direct methanol fuel cell. Even more importantly, the and #916; and mgr; technique was applied for the first time to battery relevant materials, where bulk properties such as the oxidation state and local geometry of a cathode are followed.

  8. Combined characterization of bovine polyhemoglobin microcapsules by UV-Vis absorption spectroscopy and cyclic voltammetry.

    Science.gov (United States)

    Knirsch, Marcos Camargo; Dell'Anno, Filippo; Salerno, Marco; Larosa, Claudio; Polakiewicz, Bronislaw; Eggenhöffner, Roberto; Converti, Attilio

    2017-03-01

    Polyhemoglobin produced from pure bovine hemoglobin by reaction with PEG bis(N-succynimidil succinate) as a cross-linking agent was encapsulated in gelatin and dehydrated by freeze-drying. Free carboxyhemoglobin and polyhemoglobin microcapsules were characterized by UV-Vis spectroscopy in the absorption range 450-650 nm and cyclic voltammetry in the voltage range from -0.8 to 0.6 mV to evaluate the ability to break the bond with carbon monoxide and to study the carrier's affinity for oxygen, respectively. SEM used to observe the shape of cross-linked gelatin-polyhemoglobin microparticles showed a regular distribution of globular shapes, with mean size of ~750 nm, which was ascribed to gelatin. Atomic absorption spectroscopy was also performed to detect iron presence in microparticles. Cyclic voltammetry using an Ag-AgCl electrode highlighted characteristic peaks at around -0.6 mV that were attributed to reversible oxygen bonding with iron in oxy-polyhemoglobin structure. These results suggest this technique as a powerful, direct and alternative method to evaluate the extent of hemoglobin oxygenation.

  9. Characterization of initial fluctuations for the hydrodynamical description of heavy ion collisions

    CERN Document Server

    Floerchinger, Stefan

    2013-01-01

    Event-by-event fluctuations in the initial conditions for a hydrodynamical description of heavy-ion collisions are characterized. We propose a Bessel-Fourier decomposition with respect to the azimuthal angle, the radius in the transverse plane and rapidity. This allows for a complete characterization of fluctuations in all hydrodynamical fields including energy density, pressure, fluid velocity, shear stress and bulk viscous pressure. It has the advantage that fluctuations can be ordered with respect to their wave length and that they can be propagated mode-by-mode within the hydrodynamical formalism. Event ensembles can then be characterized in terms of a functional probability distribution. For the event ensemble of a Monte Carlo Glauber model, we provide evidence that the latter is close to Gaussian form, thus allowing for a particularly simple characterization of the event distribution.

  10. Instrument for x-ray absorption spectroscopy with in situ electrical control characterizations

    International Nuclear Information System (INIS)

    Huang, Chun-Chao; Chang, Shu-Jui; Yang, Chao-Yao; Tseng, Yuan-Chieh; Chou, Hsiung

    2013-01-01

    We report a synchrotron-based setup capable of performing x-ray absorption spectroscopy and x-ray magnetic circular dichroism with simultaneous electrical control characterizations. The setup can enable research concerning electrical transport, element- and orbital-selective magnetization with an in situ fashion. It is a unique approach to the real-time change of spin-polarized electronic state of a material/device exhibiting magneto-electric responses. The performance of the setup was tested by probing the spin-polarized states of cobalt and oxygen of Zn 1-x Co x O dilute magnetic semiconductor under applied voltages, both at low (∼20 K) and room temperatures, and signal variations upon the change of applied voltage were clearly detected

  11. Beyond the electric-dipole approximation: A formulation and implementation of molecular response theory for the description of absorption of electromagnetic field radiation.

    Science.gov (United States)

    List, Nanna Holmgaard; Kauczor, Joanna; Saue, Trond; Jensen, Hans Jørgen Aagaard; Norman, Patrick

    2015-06-28

    We present a formulation of molecular response theory for the description of a quantum mechanical molecular system in the presence of a weak, monochromatic, linearly polarized electromagnetic field without introducing truncated multipolar expansions. The presentation focuses on a description of linear absorption by adopting the energy-loss approach in combination with the complex polarization propagator formulation of response theory. Going beyond the electric-dipole approximation is essential whenever studying electric-dipole-forbidden transitions, and in general, non-dipolar effects become increasingly important when addressing spectroscopies involving higher-energy photons. These two aspects are examined by our study of the near K-edge X-ray absorption fine structure of the alkaline earth metals (Mg, Ca, Sr, Ba, and Ra) as well as the trans-polyenes. In following the series of alkaline earth metals, the sizes of non-dipolar effects are probed with respect to increasing photon energies and a detailed assessment of results is made in terms of studying the pertinent transition electron densities and in particular their spatial extension in comparison with the photon wavelength. Along the series of trans-polyenes, the sizes of non-dipolar effects are probed for X-ray spectroscopies on organic molecules with respect to the spatial extension of the chromophore.

  12. Beyond the electric-dipole approximation: A formulation and implementation of molecular response theory for the description of absorption of electromagnetic field radiation

    Energy Technology Data Exchange (ETDEWEB)

    List, Nanna Holmgaard, E-mail: nhl@sdu.dk; Jensen, Hans Jørgen Aagaard [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Kauczor, Joanna; Norman, Patrick, E-mail: panor@ifm.liu.se [Department of Physics, Chemistry and Biology, Linköping University, Linköping SE 58183 (Sweden); Saue, Trond [Laboratoire de Chimie et Physique Quantiques, UMR 5626—CNRS/Université Toulouse III (Paul Sabatier), 118 route de Narbonne, F-31062 Toulouse Cedex (France)

    2015-06-28

    We present a formulation of molecular response theory for the description of a quantum mechanical molecular system in the presence of a weak, monochromatic, linearly polarized electromagnetic field without introducing truncated multipolar expansions. The presentation focuses on a description of linear absorption by adopting the energy-loss approach in combination with the complex polarization propagator formulation of response theory. Going beyond the electric-dipole approximation is essential whenever studying electric-dipole-forbidden transitions, and in general, non-dipolar effects become increasingly important when addressing spectroscopies involving higher-energy photons. These two aspects are examined by our study of the near K-edge X-ray absorption fine structure of the alkaline earth metals (Mg, Ca, Sr, Ba, and Ra) as well as the trans-polyenes. In following the series of alkaline earth metals, the sizes of non-dipolar effects are probed with respect to increasing photon energies and a detailed assessment of results is made in terms of studying the pertinent transition electron densities and in particular their spatial extension in comparison with the photon wavelength. Along the series of trans-polyenes, the sizes of non-dipolar effects are probed for X-ray spectroscopies on organic molecules with respect to the spatial extension of the chromophore.

  13. Characterizing Protein Complexes with UV absorption, Light Scattering, and Refractive Index Detection.

    Science.gov (United States)

    Trainoff, Steven

    2009-03-01

    Many modern pharmaceuticals and naturally occurring biomolecules consist of complexes of proteins and polyethylene glycol or carbohydrates. In the case of vaccine development, these complexes are often used to induce or amplify immune responses. For protein therapeutics they are used to modify solubility and function, or to control the rate of degradation and elimination of a drug from the body. Characterizing the stoichiometry of these complexes is an important industrial problem that presents a formidable challenge to analytical instrument designers. Traditional analytical methods, such as using florescent tagging, chemical assays, and mass spectrometry perturb the system so dramatically that the complexes are often destroyed or uncontrollably modified by the measurement. A solution to this problem consists of fractionating the samples and then measuring the fractions using sequential non-invasive detectors that are sensitive to different components of the complex. We present results using UV absorption, which is primarily sensitive to the protein fraction, Light Scattering, which measures the total weight average molar mass, and Refractive Index detection, which measures the net concentration. We also present a solution of the problem inter-detector band-broadening problem that has heretofore made this approach impractical. Presented will be instrumentation and an analysis method that overcome these obstacles and make this technique a reliable and robust way of non-invasively characterizing these industrially important compounds.

  14. Infrared absorption spectroscopy characterization of liquid-solid interfaces: The case of chiral modification of catalysts

    Science.gov (United States)

    Zaera, Francisco

    2018-03-01

    An overview is provided here of our work on the characterization of chiral modifiers for the bestowing of enantioselectivity to metal-based hydrogenation catalysts, with specific reference to the so-called Orito reaction. We start with a brief discussion of the use of infrared absorption spectroscopy (IR) for the characterization of chemical species at liquid-solid interfaces, describing the options available as well as the information that can be extracted from such experiments and the advantages and disadvantages associated with the technique. We then summarize the main results that we have reported to date from our IR study of the adsorption of cinchona alkaloids and related compounds from solutions onto platinum surfaces. Several observations are highlighted and placed in context in terms of the existing knowledge and their relevance to catalysis. Key conclusions include the uniqueness of the nature of the adsorbed species when in the presence of the solvent (versus when the uptake is done under vacuum, or versus the pure or dissolved molecules), the fact that each modifier adopts unique and distinct adsorption geometries on the surface and that those change with the concentration of the solution in ways that correlate well with the performance of the catalyst, the potential tendency of at least some of these chiral modifiers to bind to the surface primarily via the nitrogen atom of the amine group, not the aromatic ring as it is often assumed, and the observation that the ability of one modifier to dominate the catalytic chemistry in solutions containing mixtures of two or more of those is linked to their capacity for displacing each other from the surface, which in turn is determined by a balance between the strength of their binding to the surface and their solubility in the liquid solvent.

  15. Meso-Scale Modeling to Characterize Moisture Absorption of 3D Woven Composite

    Science.gov (United States)

    Yuan, Yuan; Zhou, Chu-wei

    2016-08-01

    For polymer-matrix composites, moisture is expected to degrade their mechanical properties due to matrix plasticization and moisture introduced micro-scale defects. In this study, the moisture absorptions of bulk epoxy, unidirectional composite (UD) and 3D woven composite (3D WC) were tested. Two-stage features have been observed for all these three materials. Moisture properties for UD and 3D WC were found not in simple direct proportion to their matrix volume fractions. The moisture approach of UD was modeled including the effect of fiber/matrix interphase which promotes the moisture uptake. Then, meso-scale FE model for 3D WC was established to characterize the inhomogeneous moisture diffusion. The moisture properties of resin-rich region and fiber bundle in 3D WC were determined from water uptake experiments of bulk epoxy and UD, respectively. Through homogenizing moisture properties of surface and interior weave structures, a simplified theoretical sandwich moisture diffusion approach was established. The moisture weight gains of 3D WC predicted by both meso-scale FE model and simplified sandwich approach were well agreed with the experimental data.

  16. Elastic characterization of closed cell foams from impedance tube absorption tests.

    Science.gov (United States)

    Chevillotte, F; Panneton, R

    2007-11-01

    A method is presented to determine the bulk elastic properties of isotropic elastic closed-cell foams from impedance tube sound absorption tests. For such foams, a resonant sound absorption is generally observed, where acoustic energy is transformed into mechanical vibration, which in turn is dissipated into heat due to structural damping. This article shows how the bulk Young's modulus, Poisson's ratio, and damping loss factor can be deduced from the resonant absorption. Also, an optimal damping loss factor yielding 100% of absorption at the first resonance is defined from the developed theory. The method is introduced for a sliding edge condition which is an ideal condition. Then, the method is extended to a bonded edge condition which is more easily achievable and additionally enables the identification of the Poisson's ratio. The method is experimentally tested on expanding closed-cell foams to find their elastic properties in both cases. Using the found properties, sound absorption predictions using an equivalent solid model with and without surface absorption are compared to measurements. Good correlations are obtained when considering surface absorption.

  17. Characterization and intercomparison of aerosol absorption photometers: result of two intercomparison workshops

    Directory of Open Access Journals (Sweden)

    T. Müller

    2011-02-01

    Full Text Available Absorption photometers for real time application have been available since the 1980s, but the use of filter-based instruments to derive information on aerosol properties (absorption coefficient and black carbon, BC is still a matter of debate. Several workshops have been conducted to investigate the performance of individual instruments over the intervening years. Two workshops with large sets of aerosol absorption photometers were conducted in 2005 and 2007. The data from these instruments were corrected using existing methods before further analysis. The inter-comparison shows a large variation between the responses to absorbing aerosol particles for different types of instruments. The unit to unit variability between instruments can be up to 30% for Particle Soot Absorption Photometers (PSAPs and Aethalometers. Multi Angle Absorption Photometers (MAAPs showed a variability of less than 5%. Reasons for the high variability were identified to be variations in sample flow and spot size. It was observed that different flow rates influence system performance with respect to response to absorption and instrumental noise. Measurements with non absorbing particles showed that the current corrections of a cross sensitivity to particle scattering are not sufficient. Remaining cross sensitivities were found to be a function of the total particle load on the filter. The large variation between the response to absorbing aerosol particles for different types of instruments indicates that current correction functions for absorption photometers are not adequate.

  18. Compact characterization of liquid absorption and emission spectra using linear variable filters integrated with a CMOS imaging camera.

    Science.gov (United States)

    Wan, Yuhang; Carlson, John A; Kesler, Benjamin A; Peng, Wang; Su, Patrick; Al-Mulla, Saoud A; Lim, Sung Jun; Smith, Andrew M; Dallesasse, John M; Cunningham, Brian T

    2016-07-08

    A compact analysis platform for detecting liquid absorption and emission spectra using a set of optical linear variable filters atop a CMOS image sensor is presented. The working spectral range of the analysis platform can be extended without a reduction in spectral resolution by utilizing multiple linear variable filters with different wavelength ranges on the same CMOS sensor. With optical setup reconfiguration, its capability to measure both absorption and fluorescence emission is demonstrated. Quantitative detection of fluorescence emission down to 0.28 nM for quantum dot dispersions and 32 ng/mL for near-infrared dyes has been demonstrated on a single platform over a wide spectral range, as well as an absorption-based water quality test, showing the versatility of the system across liquid solutions for different emission and absorption bands. Comparison with a commercially available portable spectrometer and an optical spectrum analyzer shows our system has an improved signal-to-noise ratio and acceptable spectral resolution for discrimination of emission spectra, and characterization of colored liquid's absorption characteristics generated by common biomolecular assays. This simple, compact, and versatile analysis platform demonstrates a path towards an integrated optical device that can be utilized for a wide variety of applications in point-of-use testing and point-of-care diagnostics.

  19. A theoretical framework for quantitatively characterizing sound field diffusion based on scattering coefficient and absorption coefficient of walls.

    Science.gov (United States)

    Hanyu, Toshiki

    2010-09-01

    This paper describes the development of a theoretical framework for quantitatively characterizing sound field diffusion based on scattering coefficient and absorption coefficient of walls. The concepts of equivalent scattering area, equivalent scatter reflection area, average scattering coefficient and average scatter reflection coefficient are introduced in order to express all walls' capability of scatter in a room. Using these concepts and the mean free path, scatter-to-absorption ratio, mean scatter time and diffusion time are defined in order to evaluate degree of diffusion of a space. Furthermore the effect of spatial scattering objects to sound field diffusion is formulated. In addition the time variation of specular and scattered components in a room impulse response is formulated. The verification of these characterization methods was performed with computer simulations based on the sound ray tracing method. The results supported that the ideas presented are basically valid.

  20. Characterization of Metalloproteins and Biomaterials by X-ray Absorption Spectroscopy and X-ray Diffraction

    DEFF Research Database (Denmark)

    Frankær, Christian Grundahl

    by estimation of the water content by thermogravimetric analysis. Bone tissue from dogs treated with strontiummalonate was studied using XAS. A new approach for analysing the X-ray absorption spectra resulted in a compositional model, from which the relative distribution of strontium in the different bone......-ray crystallography and X-ray absorption spectroscopy (XAS) applied to studying different hexameric insulin conformations. (iii) The structures of polymorphs of strontium ranelate and the distribution of strontium in bone tissue. A procedure for fast identification and verification of protein powders using XRPD...... and R6) were solved by single crystal X-ray diffraction (XRD) to 1.40 Å, 1.30 Å and 1.80 Å resolution, respectively. The zinc coordination in each conformation was studied by XAS including both extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray absorption near edge structure (XANES...

  1. Synthesis and Characterization of CdS/TiO2-Montmorillonite Nanocomposite with Enhanced Visible-Light Absorption

    OpenAIRE

    Feng-shan Zhou; Dai-mei Chen; Bao-lin Cui; Wei-heng Wang

    2014-01-01

    Sodium montmorillonite (MMT) was chosen as the carrier; a serial of CdS/TiO2-MMT nanocomposites with enhanced visible-light absorption ability was prepared by hydrothermal synthesis method combination with semiconductor compound modification method. The samples are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and ultraviolet visible (UV-Vis) spectroscopy; the results showed that TiO2 and CdS nanoparticles were loaded on the surface of montmorillonite unifo...

  2. Synthesis, characterization and microwave absorption of carbon-coated Cu nanocapsules

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yuping [Center for Engineering Practice and Innovation Education, Anhui University of Technology, Maanshan, (China); Feng, Chao; Liu, Xianguo; Jin, Chuangui, E-mail: liuxianguohugh@gmail.com [School of Materials Science and Engineering, Anhui University of Technology, Maanshan (China); Or, Siu Wing [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, (Hong Kong)

    2014-03-15

    The microstructure and microwave absorption of carbon-coated Cu nanocapsules have been investigated. Carbon-coated Cu nanocapsules have been synthesized by an arc-discharge method. The paraffin-Cu/C nanocapsules composite shows excellent electromagnetic (EM) absorption properties. An optimal reflection loss (RL) value of –40.0 dB is reached at 10.52 GHz for a layer 1.9 mm thickness. RL exceeding –20 dB can be realized in any interval within the 1-18 GHz range by choosing an appropriate thickness of the absorbent layer between 1.1 and 10.0 mm. Theoretical simulation for the microwave absorption using the transmission line theory agrees reasonably well with the experimental results. The EM-wave absorption properties of nanocapsules materials are illustrated by means of an absorption-tube-map. The carbon-coated Cu nano capsule is an attractive candidate for EM-wave absorption, which significantly enriches the family of EM-wave nano absorbents. (author)

  3. Thermophysics Characterization of Multiply Ionized Air Plasma Absorption of Laser Radiation

    Science.gov (United States)

    Wang, Ten-See; Rhodes, Robert; Turner, Jim (Technical Monitor)

    2002-01-01

    The impact of multiple ionization of air plasma on the inverse Bremsstrahlung absorption of laser radiation is investigated for air breathing laser propulsion. Thermochemical properties of multiply ionized air plasma species are computed for temperatures up to 200,000 deg K, using hydrogenic approximation of the electronic partition function; And those for neutral air molecules are also updated for temperatures up to 50,000 deg K, using available literature data. Three formulas for absorption are calculated and a general formula is recommended for multiple ionization absorption calculation. The plasma composition required for absorption calculation is obtained by increasing the degree of ionization sequentially, up to quadruple ionization, with a series of thermal equilibrium computations. The calculated second ionization absorption coefficient agrees reasonably well with that of available data. The importance of multiple ionization modeling is demonstrated with the finding that area under the quadruple ionization curve of absorption is found to be twice that of single ionization. The effort of this work is beneficial to the computational plasma aerodynamics modeling of laser lightcraft performance.

  4. Characterization of dissolved organic matter in Dongjianghu Lake by UV-visible absorption spectroscopy with multivariate analysis.

    Science.gov (United States)

    Zhu, Yanzhong; Song, Yonghui; Yu, Huibin; Liu, Ruixia; Liu, Lusan; Lv, Chunjian

    2017-08-08

    UV-visible absorption spectroscopy coupled with principal component analysis (PCA) and hierarchical cluster analysis (HCA) was applied to characterize spectroscopic components, detect latent factors, and investigate spatial variations of dissolved organic matter (DOM) in a large-scale lake. Twelve surface water samples were collected from Dongjianghu Lake in China. DOM contained lignin and quinine moieties, carboxylic acid, microbial products, and aromatic and alkyl groups, which in the northern part of the lake was largely different from the southern part. Fifteen spectroscopic indices were deduced from the absorption spectra to indicate molecular weight or humification degree of DOM. The northern part of the lake presented the smaller molecular weight or the lower humification degree of DOM than the southern part. E 2/4 , E 3/4 , E 2/3 , and S 2 were latent factors of characterizing the molecular weight of DOM, while E 2/5 , E 3/5 , E 2/6 , E 4/5 , E 3/6 , and A 2/1 were latent factors of evaluating the humification degree of DOM. The UV-visible absorption spectroscopy combined with PCA and HCA may not only characterize DOM fractions of lakes, but may be transferred to other types of waterscape.

  5. Flash Profile for rapid descriptive analysis in sensory characterization of passion fruit juice

    Directory of Open Access Journals (Sweden)

    Flávia Daiana Montanuci

    2015-07-01

    Full Text Available The Flash Profile is a descriptive analysis method derived from Free-Choice Profile, in which each taster chooses and uses his/her own words to evaluate the product while comparing several attributes. Four passion fruit juices were analyzed, two juices were produced with concentrated juice, one with pulp and one with reconstituted juice; all juices had different levels of sugar, some had gum and dyes. This study aimed to evaluate the physicochemical properties (color, titratable acidity and solid content as well as sensory analysis like Flash profile and affective test. In physicochemical characterization and in Flash Profile, the juice A (pulp had higher solid content and consistence, the juice B (concentrated juice was the least acidic and presented the lowest value of soluble solids and presented strong aroma and flavor of passion-fruit, the juice C (reconstituted juice was pale yellow and showed artificial flavor and the juice D (concentrated juice was the most acidic, consistent with the natural flavor. In the acceptance test, all the juices scored 5-6, indicating that panelists tasters neither liked nor disliked. Flash Profile proved to be an easy and rapid technique showing a good correlation between panelists and the attributes and confirmed the results of physicochemical characterization.

  6. Preparation, characterization and in vitro intestinal absorption of a dry emulsion formulation containing atorvastatin calcium.

    Science.gov (United States)

    Yin, Yong-Mei; Cui, Fu-De; Kim, Jung Sun; Choi, Min-Koo; Choi, Byung Chul; Chung, Suk-Jae; Shim, Chang-Koo; Kim, Dae-Duk

    2009-01-01

    A redispersible dry emulsion (DE) formulation of atorvastatin calcium (AC) was developed to enhance the in vitro dissolution of AC, thereby increasing its gastrointestinal absorption. The spray-drying technology was used where Plurol Oleique CC 497 was chosen as the oil phase. Effects of carriers, surfactants, and homogenizers on the characteristics of DE containing AC were systematically investigated. The final formulation consisted of dextrin and Poloxamer 188 as carrier and surfactant, respectively, and was homogenized by a high pressure homogenizer before spray drying. The in vitro release of AC from the optimized DE was significantly higher than that of pure AC powder (76% vs. 30% at 24 hr). The in vitro intestinal absorption of AC from the DE formulation was 0.77 microg/cm(2) at 2 hr, which was a 2.33-fold increase compared to the pure unformulated AC powder. These results suggest that the oral dry emulsion formulation could improve the intestinal absorption of AC.

  7. In-situ Characterization of Molecular Processes in Liquids by Ultrafast X-ray Absorption Spectroscopy

    Science.gov (United States)

    Chergui, Majed

    The need to visualize molecular and electronic structure in the course of a chemical reaction, a phase transformation a biological function has been the dream of scientists for decades. The development of time-resolved X-ray and electron based methods is making this true. X-ray absorption spectroscopy is ideal for the study of structural dynamics in liquids, because it can be implemented in amorphous media and it is chemically selective. Using X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) in laser pump/X-ray probe experiments allows the retrieval of the local geometric structure of the system under study, but also the underlying photoinduced electronic structure changes that drive the structural dynamics. We review the recent development in picosecond and femtosecond X-ray absorption spectroscopy applied to molecular systems in solution: examples on ultrafast photoinduced processes such as intramolecular electron transfer, high-to-low spin change, bond formation and water dynamics are presented.

  8. Characterizing the absorption properties for remote sensing of three small optically-diverse South African reservoirs

    CSIR Research Space (South Africa)

    Matthews, MW

    2013-09-01

    Full Text Available absorption at 620 nm, a(sup*)(subpc) (620), was determined as 0.007 m(sup2)·g(sup-1) in a M. aeruginosa bloom. Chl-a was a better indicator of phytoplankton biomass than phycocyanin (PC) in surface scums, due to reduced accessory pigment production...

  9. Ultra-violet and visible absorption characterization of explosives by differential reflectometry.

    Science.gov (United States)

    Dubroca, Thierry; Moyant, Kyle; Hummel, Rolf E

    2013-03-15

    This study presents some optical properties of TNT (2,4,6-trinitrotoluene), RDX, HMX and tetryl, specifically their absorption spectra as a function of concentration in various solvents in the ultraviolet and visible portion of the electromagnetic spectrum. We utilize a standoff explosives detection method, called differential reflectometry (DR). TNT was diluted in six different solvents (acetone, acetonitrile, ethanol, ethyl acetate, methanol, and toluene), which allowed for a direct comparison of absorption features over a wide range of concentrations. A line-shape analysis was adopted with great accuracy (R(2)>0.99) to model the absorption features of TNT in differential reflectivity spectra. We observed a blue shift in the pertinent absorption band with decreasing TNT concentration for all solvents. Moreover, using this technique, it was found that for all utilized solvents the concentration of TNT as well as of RDX, HMX, and tetryl, measured as a function of the transition wavelength of the ultra-violet absorption edge in differential reflectivity spectra shows three distinct regions. A model is presented to explain this behavior which is based on intermolecular hydrogen bonding of explosives molecules with themselves (or lack thereof) at different concentrations. Other intermolecular forces such as dipole-dipole interactions, London dispersion forces and π-stacking contribute to slight variations in the resulting spectra, which were determined to be rather insignificant in comparison to hydrogen bonding. The results are aimed towards a better understanding of the DR spectra of explosives energetic materials. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. A permanent Raman lidar station in the Amazon: description, characterization, and first results

    Science.gov (United States)

    Barbosa, H. M. J.; Barja, B.; Pauliquevis, T.; Gouveia, D. A.; Artaxo, P.; Cirino, G. G.; Santos, R. M. N.; Oliveira, A. B.

    2014-06-01

    A permanent UV Raman lidar station, designed to perform continuous measurements of aerosols and water vapor and aiming to study and monitor the atmosphere from weather to climatic time scales, became operational in the central Amazon in July 2011. The automated data acquisition and internet monitoring enabled extended hours of daily measurements when compared to a manually operated instrument. This paper gives a technical description of the system, presents its experimental characterization and the algorithms used for obtaining the aerosol optical properties and identifying the cloud layers. Data from one week of measurements during the dry season of 2011 were analyzed as a mean to assess the overall system capability and performance. Both Klett and Raman inversions were successfully applied. A comparison of the aerosol optical depth from the lidar and from a co-located Aerosol Robotic Network (AERONET) sun photometer showed a correlation coefficient of 0.86. By combining nighttime measurements of the aerosol lidar ratio (50-65 sr), back-trajectory calculations and fire spots observed from satellites, we showed that observed particles originated from biomass burning. Cirrus clouds were observed in 60% of our measurements. Most of the time they were distributed into three layers between 11.5 and 13.4 km a.g.l. The systematic and long-term measurements being made by this new scientific facility have the potential to significantly improve our understanding of the climatic implications of the anthropogenic changes in aerosol concentrations over the pristine Amazonia.

  11. The Chemistry of Atmosphere-Forest Exchange (CAFE Model – Part 1: Model description and characterization

    Directory of Open Access Journals (Sweden)

    G. M. Wolfe

    2011-01-01

    Full Text Available We present the Chemistry of Atmosphere-Forest Exchange (CAFE model, a vertically-resolved 1-D chemical transport model designed to probe the details of near-surface reactive gas exchange. CAFE integrates all key processes, including turbulent diffusion, emission, deposition and chemistry, throughout the forest canopy and mixed layer. CAFE utilizes the Master Chemical Mechanism (MCM and is the first model of its kind to incorporate a suite of reactions for the oxidation of monoterpenes and sesquiterpenes, providing a more comprehensive description of the oxidative chemistry occurring within and above the forest. We use CAFE to simulate a young Ponderosa pine forest in the Sierra Nevada, CA. Utilizing meteorological constraints from the BEARPEX-2007 field campaign, we assess the sensitivity of modeled fluxes to parameterizations of diffusion, laminar sublayer resistance and radiation extinction. To characterize the general chemical environment of this forest, we also present modeled mixing ratio profiles of biogenic hydrocarbons, hydrogen oxides and reactive nitrogen. The vertical profiles of these species demonstrate a range of structures and gradients that reflect the interplay of physical and chemical processes within the forest canopy, which can influence net exchange.

  12. Fabrication process and electromagnetic wave absorption characterization of a CNT/Ni/epoxy nanocomposite.

    Science.gov (United States)

    Ryu, Seongwoo; Mo, Chan Bin; Lee, Haeshin; Hong, Soon Hyung

    2013-11-01

    Since carbon nanotube (CNT) was first discovered in 1991, it has been considered as a viable type of conductive filler for electromagnetic wave absorption materials in the GHz range. In this paper, pearl-necklace-structure CNT/Ni nano-powders were fabricated by a polyol process as conductive fillers. Compared to synthesized CNT, pearl-necklace Ni-decorated CNT increased the electrical conductivity by an order of 1 due to the enhancement of the Ni-conductive network. Moreover, the decorated Ni particles prevented the agglomeration of CNTs by counterbalancing the Van der Walls interaction between the CNTs. A CNT/Ni nanocomposite showed a homogeneous dispersion in an epoxy-based matrix. This enhanced physical morphology and electrical properties lead to an increase in the loss tangent and reflection loss in the CNT/Ni/Epoxy nanocomposite compared to these characteristics of a CNT/Epoxy nanocomposite in range of 8-12 GHz. The electromagnetic wave absorption properties of CNT/Ni/epoxy nanocomposites will provide enormous opportunities for electronic applications where lightweight EMI shielding or electro-magnetic wave absorption properties are necessary.

  13. Characterization of water absorption by CFRP using air-coupled ultrasonic testing

    International Nuclear Information System (INIS)

    Lee, Joo Min; Lee, Joo Sung; Park, Ik Keun; Kim, Yong Kwon

    2014-01-01

    Carbon-fiber-reinforced plastic (CFRP) composites are increasingly being used in a variety of industry applications, such as aircraft, automobiles, and ships because of their high specific stiffness and high specific strength. Aircraft are exposed to high temperatures and high humidity for a long duration during flights. CFRP materials of the aircraft can absorb water, which could decrease the adhesion strength of these materials and cause their volumes to change with variation in internal stress. Therefore, it is necessary to estimate the characteristics of CFRP composites under actual conditions from the viewpoint of aircraft safety. In this study air-coupled ultrasonic testing (ACUT) was applied to the evaluation of water absorption properties of CFRP composites. CFRP specimens were fabricated and immersed in distilled water at 75 degree C for 30, 60, and 120 days, after which their ultrasonic images were obtained by ACUT. The water absorption properties were determined by quantitatively analyzing the changes in ultrasonic signals. Further, shear strength was applied to the specimens to verify the changes in their mechanical properties for water absorption.

  14. Characterization of the photoreaction between DNA and aminomethyl-trimethylpsoralen using absorption and fluorescence spectroscopy

    International Nuclear Information System (INIS)

    Johnston, B.H.; Hearst, J.E.

    1981-01-01

    The use of absorption and fluorescence spectroscopy for following the progress of the photoreaction between DNA and 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT) has been investigated. Absorption at long wavelengths and fluorescence both decline upon intercalation of AMT into the DNA helix. The loss of fluorescence from AMT and the accompanying appearance of monoadduct fluorescence upon irradiation by UV light can be easily followed by using the excitation beam of a spectrofluorometer as the source of irradiation and monitoring the changing emission spectrum. Where cross-link formation is possible, the subsequent decline of monoadduct fluorescence is seen as well. This suggests that the 4',5'-monoadduct is a precursor of cross-links. Both monoaddition and cross-linking are more rapid with poly d(A-T) than with calf thymus DNA or poly d(A.T). Excitation spectra can be helpful in resolving the levels of AMT and 4',5'-monoadduct when both are contributing to the emission spectrum. Some changes are observed in the emission spectrum of AMT-poly d(A.T) monoadducts after prolonged irradiation which indicate further photoreaction. (author)

  15. Molecular characterization of copper in soils using X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Strawn, Daniel G.; Baker, Leslie L.

    2009-01-01

    Bioavailability of Cu in the soil is a function of its speciation. In this paper we investigated Cu speciation in six soils using X-ray absorption near edge structure (XANES), extended X-ray absorption fine structure (EXAFS), and synchrotron-based micro X-ray fluorescence (μ-XRF). The XANES and EXAFS spectra in all of the soils were the same. μ-XRF results indicated that the majority of the Cu particles in the soils were not associated with calcium carbonates, Fe oxides, or Cu sulfates. Principal component analysis and target transform of the XANES and EXAFS spectra suggested that Cu adsorbed on humic acid (HA) was an acceptable match. Thus it appears that Cu in all of the soils is primarily associated with soil organic matter (SOM). Theoretical fitting of the molecular structure in the soil EXAFS spectra revealed that the Cu in the soils existed as Cu atoms bound in a bidentate complex to O or N functional groups. - Copper speciation in six soils was investigated using XANES, EXAFS, and μ-XRF.

  16. Ellipsometric analysis and optical absorption characterization of gallium phosphide nanoparticulate thin film

    International Nuclear Information System (INIS)

    Zhang Qi-Xian; Ruan Fang-Ping; Wei Wen-Sheng

    2011-01-01

    Gallium phosphide (GaP) nanoparticulate thin films were easily fabricated by colloidal suspension deposition via GaP nanoparticles dispersed in N,N-dimethylformamide. The microstructure of the film was performed by x-ray diffraction, high resolution transmission electron microscopy and field emission scanning electron microscopy. The film was further investigated by spectroscopic ellipsometry. After the model GaP+void|SiO 2 was built and an effective medium approximation was adopted, the values of the refractive index n and the extinction coefficient k were calculated for the energy range of 0.75 eV–4.0 eV using the dispersion formula in DeltaPsi2 software. The absorption coefficient of the film was calculated from its k and its energy gaps were further estimated according to the Tauc equation, which were further verified by its fluorescence spectrum measurement. The structure and optical absorption properties of the nanoparticulate films are promising for their potential applications in hybrid solar cells. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  17. In Vitro Characterization of the Biomimetic Properties of Poly(dimethylsiloxane) To Simulate Oral Drug Absorption.

    Science.gov (United States)

    Sinko, Patrick D; Gidley, David; Vallery, Richard; Lamoureux, Aaron; Amidon, Gordon L; Amidon, Gregory E

    2017-12-04

    The potential use of poly(dimethylsiloxane) (PDMS) as an in vitro biomimetic analogue of the passive drug absorption process in the human gastrointestinal tract (GI) is assessed. PDMS is biomimetic because of similarities in small molecule transport, such as mechanism, ionization selectivity, lipophilicity. Nine molecular probes are used to evaluate the transport pathways and properties used to predict human oral absorption rates. The transport pathways through PDMS (bulk/pore) are analogous to transcellular (TCDT) and paracellular (PCDT) drug transport pathways. PDMS PCDT is assessed using positronium annihilation lifetime spectroscopy (PALS) and partition experiments; TCDT using diffusion and partition experiments. PALS determined that PDMS pores were uniform (D ∼ 0.85 nm), isolated, and void volume was unaffected by drug accumulation after equilibrium partitioning. Therefore, there is no PCDT or convective flow through PDMS. A strong linear correlation exists between predicted octanol-water partition coefficients and PDMS partition coefficients (LogK PDMS = 0.736 × LogP O-W - 0.971, R 2 = 0.981). The pH-partition hypothesis is confirmed in PDMS using ibuprofen over pH 2-12. Diffusivity through PDMS is a function of lipophilicity and polar surface area K × D PDMS = 4.46 × 10 -8 × e 2.91×LogK PDMS (R 2 = 0.963) and [Formula: see text] (R 2 = 0.973). Varying the mass% of curing agent changed the lipophilicity and diffusivity (p < 0.02), but not practically (K × D = 2.23 × 10 -5 cm 2 s -1 vs 2.60 × 10 -5 cm 2 s -1 ), and does affect elastic modulus (3.2% = 0.3 MPa to 25% = 3.2 MPa).

  18. Characterizing ablation and aerosol generation during elemental fractionation on absorption modified lithium tetraborate glasses using LA-ICP-MS.

    Science.gov (United States)

    Weis, Peter; Beck, Horst P; Günther, Detlef

    2005-01-01

    The influence of sample matrix composition, absorption behavior and laser aerosol particle size distribution on elemental fractionation in laser ablation inductively coupled plasma mass spectrometry was studied for nanosecond laser ablation at a wavelength of 266 nm. To this end, lithium tetraborate glass samples with different iron oxide contents and trace amounts of a group of 11 elements were prepared synthetically. The samples were characterized in terms of optical absorbance, melting points, trace element concentrations and homogeneity. UV/VIS spectra showed that sample absorption rises with increasing Fe2O3 content. Crater depths and time-dependent particle size distributions were measured, and ablated and transported sample volumes were estimated. Furthermore, the laser aerosol was filtered using a particle separation device and transient ICP-MS signals were acquired with and without filtering the aerosol. The results demonstrate that the amount of ablated sample is related to the absorption coefficient of the sample and therefore to the optical penetration depth of the laser beam into the sample. The higher energy densities resulting from the shorter penetration depths result in smaller average particle sizes for highly absorbing samples, which allows more efficient transport to and atomization and excitation of the ablated material within the ICP. The particle size distribution changes continuously with ablation time, and larger particle fractions occur mainly at the beginning of the ablation, which leads to particle-related fractionation processes at the beginning of the transient signal. Exceeding a critical depth to diameter ratio, laser-related elemental fractionation processes occur. Changes in the volatile to non-volatile element intensity ratio after the aerosol is filtered indicate that particle size-related enrichment processes contribute to elemental fractionation.

  19. Characterization of the Electronic Structure of Silicon Nanoparticles Using X-ray Absorption and Emission

    Energy Technology Data Exchange (ETDEWEB)

    Vaverka, April Susan Montoya [Univ.of California, Davis, CA (United States)

    2008-01-01

    Resolving open questions regarding transport in nanostructures can have a huge impact on a broad range of future technologies such as light harvesting for energy. Silicon has potential to be used in many of these applications. Understanding how the band edges of nanostructures move as a function of size, surface termination and assembly is of fundamental importance in understanding the transport properties of these materials. In this thesis work I have investigated the change in the electronic structure of silicon nanoparticle assemblies as the surface termination is changed. Nanoparticles are synthesized using a thermal evaporation technique and sizes are determined using atomic force microscopy (AFM). By passivating the particles with molecules containing alcohol groups we are able to modify the size dependent band edge shifts. Both the valence and conduction bands are measured using synchrotron based x-ray absorption spectroscopy (XAS) and soft x-ray fluorescence (SXF) techniques. Particles synthesized via recrystallization of amorphous silicon/SiO2 multilayers of thicknesses below 10 nm are also investigated using the synchrotron techniques. These samples also show quantum confinement effects but the electronic structure is different from those synthesized via evaporation methods. The total bandgap is determined for all samples measured. The origins of these differences in the electronic structures are discussed.

  20. Plutonium-uranium mixed oxide characterization by coupling micro-X-ray diffraction and absorption investigations

    Science.gov (United States)

    Degueldre, C.; Martin, M.; Kuri, G.; Grolimund, D.; Borca, C.

    2011-09-01

    Plutonium-uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The potential differences of metal redox state and microstructural developments of the matrix before and after irradiation are commonly analysed by electron probe microanalysis. In this work the structure and next-neighbor atomic environments of Pu and U oxide features within unirradiated homogeneous MOX and irradiated (60 MW d kg -1) MOX samples was analysed by micro-X-ray fluorescence (μ-XRF), micro-X-ray diffraction (μ-XRD) and micro-X-ray absorption fine structure (μ-XAFS) spectroscopy. The grain properties, chemical bonding, valences and stoichiometry of Pu and U are determined from the experimental data gained for the unirradiated as well as for irradiated fuel material examined in the center of the fuel as well as in its peripheral zone (rim). The formation of sub-grains is observed as well as their development from the center to the rim (polygonization). In the irradiated sample Pu remains tetravalent (>95%) and no (oxidation in the rim zone. Any slight potential plutonium oxidation is buffered by the uranium dioxide matrix while locally fuel cladding interaction could also affect the redox of the fuel.

  1. Fourier transform infrared absorption spectroscopy characterization of gaseous atmospheric pressure plasmas with 2 mm spatial resolution

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, G. [Laboratoire d' Ingenierie de Surface, Centre de Recherche sur les Materiaux Avances, Departement de genie des mines, de la metallurgie et des materiaux, Universite Laval, 1065, avenue de la Medecine, Quebec G1V 0A6 (Canada); Centre de recherche du CHUQ, Hopital St Francois d' Assise, 10, rue de l' Espinay, local E0-165, Quebec G1L 3L5 (Canada); Vallade, J. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Agence de l' environnement et de la Ma Latin-Small-Letter-Dotless-I -carettrise de l' Energie, 20, avenue du Gresille, BP 90406, F-49004 Angers Cedex 01 (France); Bazinette, R.; Hernandez, E.; Hernandez, G.; Massines, F. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Nijnatten, P. van [OMT Solutions bv, High Tech Campus 9, 5656AE Eindhoven (Netherlands)

    2012-10-15

    This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm Multiplication-Sign 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45 Degree-Sign beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma.

  2. Characterization of Nanocrystalline SiGe Thin Film Solar Cell with Double Graded-Dead Absorption Layer

    Directory of Open Access Journals (Sweden)

    Chao-Chun Wang

    2012-01-01

    Full Text Available The nanocrystalline silicon-germanium (nc-SiGe thin films were deposited by high-frequency (27.12 MHz plasma-enhanced chemical vapor deposition (HF-PECVD. The films were used in a silicon-based thin film solar cell with graded-dead absorption layer. The characterization of the nc-SiGe films are analyzed by scanning electron microscopy, UV-visible spectroscopy, and Fourier transform infrared absorption spectroscopy. The band gap of SiGe alloy can be adjusted between 0.8 and 1.7 eV by varying the gas ratio. For thin film solar cell application, using double graded-dead i-SiGe layers mainly leads to an increase in short-circuit current and therefore cell conversion efficiency. An initial conversion efficiency of 5.06% and the stabilized efficiency of 4.63% for an nc-SiGe solar cell were achieved.

  3. Studies on Characterization, Optical Absorption, and Photoluminescence of Yttrium Doped ZnS Nanoparticles

    OpenAIRE

    Viswanath, Ranganaik; Naik, Halehatty Seethya Bhojya; Somalanaik, Yashavanth Kumar Gubbihally; Neelanjeneallu, Prashanth Kumar Parlesed; Harish, Khandugadahalli Nagarajappa; Prabhakara, Mustur Channabasappa

    2014-01-01

    Pure ZnS and ZnS:Y nanoparticles were synthesized by a chemical coprecipitation route using EDTA-ethylenediamine as a stabilizing agent. X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectrometry (FTIR), thermogravimetric-differential scanning calorimetry (TG-DSC), and UV-visible and photoluminescence (PL) spectroscopy were employed to characterize the as-synthesized ZnS and Z...

  4. Structural Characterization of 1,1,3,3-Tetramethylguanidinium Chloride Ionic Liquid by Reversible SO2 Gas Absorption

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Harris, Pernille; Riisager, Anders

    2013-01-01

    A unique new ionic liquid−gas adduct solid state compound formed between 1,1,3,3-tetramethylguanidinium chloride ([tmgH]Cl) and sulfur dioxide has been characterized by X-ray diffraction and Raman spectroscopy. The structure contains SO2 molecules of near normal structure kept at their positions...... by Cl−S interactions. The crystals belong in the orthorhombic system, space group Pbcn, with unit cell dimensions of a = 15.6908(10) Å, b = 9.3865(6) Å, and c = 14.1494(9) Å, angles α = β = γ = 90°, and Z = 8 at 120 K. The [tmgH]Cl has a very high absorption capacity of nearly 3 mol of SO2 per mol...

  5. Characterization of ion-assisted induced absorption in A-Si thin-films used for multivariate optical computing

    Science.gov (United States)

    Nayak, Aditya B.; Price, James M.; Dai, Bin; Perkins, David; Chen, Ding Ding; Jones, Christopher M.

    2015-06-01

    Multivariate optical computing (MOC), an optical sensing technique for analog calculation, allows direct and robust measurement of chemical and physical properties of complex fluid samples in high-pressure/high-temperature (HP/HT) downhole environments. The core of this MOC technology is the integrated computational element (ICE), an optical element with a wavelength-dependent transmission spectrum designed to allow the detector to respond sensitively and specifically to the analytes of interest. A key differentiator of this technology is it uses all of the information present in the broadband optical spectrum to determine the proportion of the analyte present in a complex fluid mixture. The detection methodology is photometric in nature; therefore, this technology does not require a spectrometer to measure and record a spectrum or a computer to perform calculations on the recorded optical spectrum. The integrated computational element is a thin-film optical element with a specific optical response function designed for each analyte. The optical response function is achieved by fabricating alternating layers of high-index (a-Si) and low-index (SiO2) thin films onto a transparent substrate (BK7 glass) using traditional thin-film manufacturing processes (e.g., ion-assisted e-beam vacuum deposition). A proprietary software and process are used to control the thickness and material properties, including the optical constants of the materials during deposition to achieve the desired optical response function. The ion-assisted deposition is useful for controlling the densification of the film, stoichiometry, and material optical constants as well as to achieve high deposition growth rates and moisture-stable films. However, the ion-source can induce undesirable absorption in the film; and subsequently, modify the optical constants of the material during the ramp-up and stabilization period of the e-gun and ion-source, respectively. This paper characterizes the unwanted

  6. A multiwavelength continuum characterization of high-redshift broad absorption line quasars

    Science.gov (United States)

    Tuccillo, D.; Bruni, G.; DiPompeo, M. A.; Brotherton, M. S.; Pasetto, A.; Kraus, A.; González-Serrano, J. I.; Mack, K.-H.

    2017-06-01

    We present the results of a multiwavelength study of a sample of high-redshift radio-loud (RL) broad absorption line (BAL) quasars. This way, we extend to higher redshift previous studies on the radio properties and broad-band optical colours of these objects. We have selected a sample of 22 RL BAL quasars with 3.6 ≤ z ≤ 4.8 cross-correlating the FIRST radio survey with the Sloan Digital Sky Survey (SDSS). Flux densities between 1.25 and 9.5 GHz have been collected with the Jansky Very Large Array and Effelsberg-100 m telescopes for 15 BAL and 14 non-BAL quasars used as a comparison sample. We determine the synchrotron peak frequency, constraining their age. A large number of gigahertz peaked spectrum and high-frequency peakers sources have been found in both samples (80 per cent for BAL and 71 per cent for non-BAL quasars), not suggesting a younger age for BAL quasars. The spectral index distribution provides information about the orientation of these sources, and we find statistically similar distributions for the BAL and non-BAL quasars in contrast to work done on lower redshift samples. Our sample may be too small to convincingly find the same effect, or might represent a real evolutionary effect based on the large fraction of young sources. We also study the properties of broad-band colours in both optical (SDSS) and near- and mid-infrared (UK Infrared Telescope Deep Sky Survey and Wide-field Infrared Survey Explorer - WISE) bands, finding that also at high-redshift BAL quasars tend to be optically redder than non-BAL quasars. However, these differences are no more evident at longer wavelength, when comparing colours of the two samples by mean of the WISE survey.

  7. Preformulation characterization and in vivo absorption in beagle dogs of JFD, a novel anti-obesity drug for oral delivery.

    Science.gov (United States)

    Fan, Yunzhou; Yang, Meiyan; Wang, Yuli; Li, Yanyou; Zhou, Yuanda; Chen, Xiaoping; Shan, Li; Wei, Jun; Gao, Chunsheng

    2015-05-01

    JFD (N-isoleucyl-4-methyl-1,1-cyclopropyl-1-(4-chlorine)phenyl-2-amylamine·HCl) is a novel investigational anti-obesity drug without obvious cardiotoxicity. The objective of this study was to characterize the key physicochemical properties of JFD, including solution-state characterization (ionization constant, partition coefficient, aqueous and pH-solubility profile), solid-state characterization (particle size, thermal analysis, crystallinity and hygroscopicity) and drug-excipient chemical compatibility. A supporting in vivo absorption study was also carried out in beagle dogs. JFD bulk powders are prismatic crystals with a low degree of crystallinity, particle sizes of which are within 2-10 μm. JFD is highly hygroscopic, easily deliquesces to an amorphous glass solid and changes subsequently to another crystal form under an elevated moisture/temperature condition. Similar physical instability was also observed in real-time CheqSol solubility assay. pK(a) (7.49 ± 0.01), log P (5.10 ± 0.02) and intrinsic solubility (S0) (1.75 μg/ml) at 37 °C of JFD were obtained using potentiometric titration method. Based on these solution-state properties, JFD was estimated to be classified as BCS II, thus its dissolution rate may be an absorption-limiting step. Moreover, JFD was more chemically compatible with dibasic calcium phosphate, mannitol, hypromellose and colloidal silicon dioxide than with lactose and magnesium stearate. Further, JFD exhibited an acceptable pharmacokinetic profiling in beagle dogs and the pharmacokinetic parameters T(max), C(max), AUC(0-t) and absolute bioavailability were 1.60 ± 0.81 h, 0.78 ± 0.47 μg/ml, 3.77 ± 1.85 μg·h/ml and 52.30 ± 19.39%, respectively. The preformulation characterization provides valuable information for further development of oral administration of JFD.

  8. Absorption in the Cosmic Web: Characterizing the Intergalactic Medium in Cosmological Filaments

    Science.gov (United States)

    Tejos, Nicolas

    2014-10-01

    We propose to observe and characterize the IGM associated with cosmological filaments in a statistical manner up to redshift ~0.4. For this purpose, we have used a published cluster catalog (Hao et al. 2010) to identify massive nodes in the cosmic web. We used cluster-pairs separated by 10 to ensure a full characterization of HI and OVI lines at column densities N~10^13 cm^-2. This setup will allow us to detect broad and shallow HI and OVI lines (if any) at the redshifts of these filaments, believed to trace portions of the warm-hot intergalactic medium (WHIM). Combining these new observations with those from our pilot study carried out in cycle 20 (ID 12958, PI Tejos), we aim to provide a firm detection of the WHIM in cosmological filaments, at the 95% confidence level. Our findings will test our understanding of galaxy formation and the role of AGN/supernova feedback by comparing them with state-of-the-art hydrodynamical simulations. We will also test the the hypothesis which states that the majority of OVI absorbers at low-z are confined within <300 kpc from galaxies (i.e. circumgalactic medium) thus not related to the WHIM (Prochaska et al. 2011; Tumlinson et al. 2011).

  9. Studies on Characterization, Optical Absorption, and Photoluminescence of Yttrium Doped ZnS Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ranganaik Viswanath

    2014-01-01

    Full Text Available Pure ZnS and ZnS:Y nanoparticles were synthesized by a chemical coprecipitation route using EDTA-ethylenediamine as a stabilizing agent. X-ray diffraction (XRD, high resolution transmission electron microscopy (HRTEM, field emission scanning electron microscopy (FE-SEM, Fourier transform infrared spectrometry (FTIR, thermogravimetric-differential scanning calorimetry (TG-DSC, and UV-visible and photoluminescence (PL spectroscopy were employed to characterize the as-synthesized ZnS and ZnS:Y nanoparticles, respectively. XRD and TEM studies show the formation of cubic ZnS:Y particles with an average size of ~4.5 nm. The doping did not alter the phase of the zinc sulphide, as a result the sample showed cubic zincblende structure. The UV-visible spectra of ZnS and ZnS:Y nanoparticles showed a band gap energy value, 3.85 eV and 3.73 eV, which corresponds to a semiconductor material. A luminescence characteristics such as strong and stable visible-light emissions in the orange region alone with the blue emission peaks were observed for doped ZnS nanoparticles at room temperature. The PL intensity of orange emission peak was found to be increased with an increase in yttrium ions concentration by suppressing blue emission peaks. These results strongly propose that yttrium doped zinc sulphide nanoparticles form a new class of luminescent material.

  10. Absorption and Scattering by Molecules and Particles

    Science.gov (United States)

    Lenoble, Jacqueline; Mishchenko, Michael I.; Herman, Maurice

    2013-01-01

    The Earth's atmosphere absorbs, scatters, and emits electromagnetic radiation. Although air molecules are the primary actors in these processes, aerosol particles are also present ubiquitously and modify the radiation field. In fact, this modification constitutes the very physical basis of aerosol remote sensing. Whenever clouds are present, they have a much larger influence on radiation which largely overshadows the aerosol impact. Therefore, in aerosol remote sensing, one often has to limit observations to cloudless conditions and screen cloudy pixels. In the solar part of the spectrum, molecular absorption is mostly limited to ultraviolet (UV; ozone) and near-infrared (near-IR; carbon dioxide, water vapor) wavelengths and is characterized by strong and narrow oxygen bands. A brief description of atmospheric molecular absorption is presented in Section 2.2. Shortwave aerosol remote sensing is usually performed outside the absorption bands, but some instruments also have channels capturing absorption bands with the objective of quantifying gaseous components.

  11. Nitrogen oxide absorption into water and dilute nitric acid in an engineering-scale sieve-plate column: description of a mathematical model and comparison with experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Counce, R M

    1978-09-01

    The study reported here is concerned with the absorption of gaseous NO/sub x/ compounds into water and dilute HNO/sub 3/ in a three-stage sieve-plate column with plates designed for high gas-liquid interfacial area. The performance of the column was measured while several operating parameters were varied. A mechanistic model was developed and presented to explain the observed phenomena. The results of the study indicate the importance of three mechanisms in the absorption of gaseous NO/sub x/ compounds: (a) the absorption of NO/sub 2/*, which results in the production of liquid HNO/sub 3/ and HNO/sub 2/; (b) the dissociation of the liquid HNO/sub 2/ into HNO/sub 3/ and gaseous NO; and (c) the gas-phase oxidation of NO to NO/sub 2/. A useful model was developed to explain the absorption of NO/sub x/ compounds based on the above mechanisms. This model is presented and discussed.

  12. Characterization of Flow Dynamics and Reduced-Order Description of Experimental Two-Phase Pipe Flow

    Science.gov (United States)

    Viggiano, Bianca; SkjæRaasen, Olaf; Tutkun, Murat; Cal, Raul Bayoan

    2017-11-01

    Multiphase pipe flow is investigated using proper orthogonal decomposition for tomographic X-ray data, where holdup, cross sectional phase distributions and phase interface characteristics are obtained. Instantaneous phase fractions of dispersed flow and slug flow are analyzed and a reduced order dynamical description is generated. The dispersed flow displays coherent structures in the first few modes near the horizontal center of the pipe, representing the liquid-liquid interface location while the slug flow case shows coherent structures that correspond to the cyclical formation and breakup of the slug in the first 10 modes. The reconstruction of the fields indicate that main features are observed in the low order dynamical descriptions utilizing less than 1 % of the full order model. POD temporal coefficients a1, a2 and a3 show interdependence for the slug flow case. The coefficients also describe the phase fraction holdup as a function of time for both dispersed and slug flow. These flows are highly applicable to petroleum transport pipelines, hydroelectric power and heat exchanger tubes to name a few. The mathematical representations obtained via proper orthogonal decomposition will deepen the understanding of fundamental multiphase flow characteristics.

  13. Characterization by time-resolved UV/Vis and infrared absorption spectroscopy of an intramolecular charge-transfer state in an organic electron-donor-bridge-acceptor system

    NARCIS (Netherlands)

    Hviid, L.; Verhoeven, J.W.; Brouwer, A.M.; Paddon-Row, M.N.; Yang, J.

    2004-01-01

    A long-lived intramolecular charge-separated state in an electron-donor-acceptor molecule is characterized by time-resolved visible and infrared absorption spectroscopy. Bands that can be assigned to the negatively charged acceptor chromophore can be clearly observed in the time-resolved IR

  14. Application of Physiologically Based Absorption Modeling to Characterize the Pharmacokinetic Profiles of Oral Extended Release Methylphenidate Products in Adults.

    Directory of Open Access Journals (Sweden)

    Xiaoxia Yang

    Full Text Available A previously presented physiologically-based pharmacokinetic model for immediate release (IR methylphenidate (MPH was extended to characterize the pharmacokinetic behaviors of oral extended release (ER MPH formulations in adults for the first time. Information on the anatomy and physiology of the gastrointestinal (GI tract, together with the biopharmaceutical properties of MPH, was integrated into the original model, with model parameters representing hepatic metabolism and intestinal non-specific loss recalibrated against in vitro and in vivo kinetic data sets with IR MPH. A Weibull function was implemented to describe the dissolution of different ER formulations. A variety of mathematical functions can be utilized to account for the engineered release/dissolution technologies to achieve better model performance. The physiological absorption model tracked well the plasma concentration profiles in adults receiving a multilayer-release MPH formulation or Metadate CD, while some degree of discrepancy was observed between predicted and observed plasma concentration profiles for Ritalin LA and Medikinet Retard. A local sensitivity analysis demonstrated that model parameters associated with the GI tract significantly influenced model predicted plasma MPH concentrations, albeit to varying degrees, suggesting the importance of better understanding the GI tract physiology, along with the intestinal non-specific loss of MPH. The model provides a quantitative tool to predict the biphasic plasma time course data for ER MPH, helping elucidate factors responsible for the diverse plasma MPH concentration profiles following oral dosing of different ER formulations.

  15. Customer System Efficiency Improvement Assessment: Description and examination of system characterization data

    Energy Technology Data Exchange (ETDEWEB)

    Callaway, J.W.; DeSteese, J.G.

    1986-12-01

    This report describes three data bases that were developed in the Customer System Efficiency Improvement (CSEI) Assessment project to help characterize transmission and distribution (T and D) system losses experienced by utility customers in the Pacific Northwest. A principal objective of this project is to assess the potential for electric energy conservation in the T and D systems of BPA's utility customers. The three data bases provide essential input on the number and operating characteristics of T and D component stocks that was used in another task of the CSEI Project to estimate the conservation supply functions that result from replacing existing stocks with more efficient components (Tepel et al. 1986). This document describes the three data bases, provides a guide to their use, and presents a summary characterization of the principal loss-generating components (lines and transformers) of the region's T and D systems.

  16. Atmospheric Absorption Cell Characterization.

    Science.gov (United States)

    1982-06-01

    was adequate for making empty cell measurements and filling the cell with artificial atmospheres. The procedure used in pumping and fillin the cell...carbon dioxide, nitrogen, and nitrous oxide. The artificial atmospheres in the cell used for these measurements are summarized in Table IV. Figures...LD_l -_10J J« LUZ . jr-U «—• »r—• «-CD CO — Q- —a CD -j" \\z — OC I — h- \\_IC\\J CM LUD -ÜU T 1 r 00*001 00󈧌 00*09 00*0

  17. Overview of waste isoltaion safety assessment program and description of source term characterization task at PNL

    International Nuclear Information System (INIS)

    Bradley, D.

    1977-01-01

    A project is being conducted to develop and illustrate the methods and obtain the data necessary to assess the safety of long-term disposal of high-level radioactive waste in geologic formations. The methods and data will initially focus on generic geologic isolation systems but will ultimately be applied to the long-term safety assessment of specific candidate sites that are selected in the NWTS Program. The activities of waste isolation safety assessment (WISAP) are divided into six tasks: (1) Safety Assessment Concepts and Methods, (2) Disruptive Event Analysis, (3) Source Characterization, (4) Transport Modeling, (5) Transport Data and (6) Societal Acceptance

  18. Characterization of biochar-derived dissolved organic matter using UV-visible absorption and excitation-emission fluorescence spectroscopies.

    Science.gov (United States)

    Jamieson, Tyler; Sager, Eric; Guéguen, Céline

    2014-05-01

    In recent years, biochar has become of considerable interest for a variety of environmental applications. However, the feasibility of its application is entirely dependent on its physical and chemical properties, including the characteristics of biochar-derived dissolved organic matter (DOM). The goal of this study was to assess the use of optical analysis for the purpose of characterizing biochar-derived DOM. Three different biochars (slow pyrolysis birch and maple; fast pyrolysis maple) were produced and leached in distilled water over 17d. Samples were taken on days 3, 10, 13 and 17, filtered, and analyzed for DOC content. Samples were also subjected to optical analysis using UV-visible absorption and excitation-emission matrix (EEM) fluorescence spectroscopies. EEM fluorescence data were further analyzed using parallel factor analysis (PARAFAC). Absorbance and fluorescence results were combined and examined using principal component analysis (PCA). Significant differences in the water soluble organic carbon content were observed for all biochar types. The estimated aromaticity (SUVA254) and mean molecular weight (S275-295) of biochar-derived DOM were also found to differ based on biochar type. PARAFAC analysis identified three humic-like components and one protein-like component. Distinct DOM signatures were observed for each biochar type. Transformations in biochar DOM characteristics over time were also observed. The PCA showed a clear delineation in biochar types based on their optical properties. The results of this study indicate that optical analysis may provide valuable information regarding the characteristics of biochar-derived DOM. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Absorption heat pumps

    International Nuclear Information System (INIS)

    Formigoni, C.

    1998-01-01

    A brief description of the difference between a compression and an absorption heat pump is made, and the reasons why absorption systems have spread lately are given. Studies and projects recently started in the field of absorption heat pumps, as well as criteria usually followed in project development are described. An outline (performance targets, basic components) of a project on a water/air absorption heat pump, running on natural gas or LPG, is given. The project was developed by the Robur Group as an evolution of a water absorption refrigerator operating with a water/ammonia solution, which has been on the market for a long time and recently innovated. Finally, a list of the main energy and cost advantages deriving from the use of absorption heat pumps is made [it

  20. Characterization of metallic nanoparticles by high-resolution X-ray absorption and X-ray emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Timna-Josua

    2012-03-15

    In almost all areas of technology, metallic nanoparticles are of interest due to their special thermal, electronic, magnetic and optical properties. Their special properties are mainly due to their small size which implies the relevance of quantum effects as well as the significance of the surface: For 2 nm nanoparticles, the surface-to-volume ratio is already 1:1. However, the identification of surface-to-volume interactions - that are responsible for the new properties - is a difficult task due to the small size that inhibits a lot of 'standard' techniques to be applicable. Here X-ray absorption/emission spectroscopy (XAS/XES) is a favorable tool for the characterization of nanoparticles, independent on size, degree of crystallinity and shape/condition of the surface. Using XAS, a tempered nanosized Co{sub 3}Pt/C catalyst have been investigated. Its outstanding oxygen-reduction reaction (ORR) properties in a fuel cell could be related to a lowered Pt 5d-band center connected to a tightened Pt-Pt bonding distance, leading to a weakening of the oxygen adsorption strength so that the ORR may proceed faster. One drawback remains, however, as the properties found by (standard) XAS are summed up for different chemical environments of the chosen element. Thus, no distinction can be made between, e.g., the pure metal in a nanoparticles' interior and the ligated metal in the outer shells or surface. Here, high-resolution fluorescence-detected XAS (HRFD-XAS) provides additional opportunities as, due to its chemical sensitivity, it leads to site-selective XAS. For a system of 6 nm sized Co nanoparticles, build up of a metallic core surrounded by a protecting shell, that resulted from the 'smooth oxidation' process, this technique of site-selective XAS was proven to be applicable. For the first time, the interior and outer shell of a metallic nanoparticle could be characterized separately. In particular, the Co-hcp phase could be determined for the

  1. Micro-radiography and micro-computerized tomography with absorption and phase contrast for materials characterization; Mikro-Radiografie und Mikro-Computertomografie mit Absorptions- und Phasenkontrast fuer die Materialcharakterisierung

    Energy Technology Data Exchange (ETDEWEB)

    Kastner, Johann [FH Oberoesterreich, Wels (Austria)

    2017-08-01

    The contribution describes modern techniques in micro-radiography and micro-computerized tomography for materials characterization using absorption and phase contrast. Using micro- and nano-focus tubes and adequate high.-resolution detectors it is possible to reach resolutions significantly below 1 micron. The CT technology allows in-situ deformation testing to study the damaging mechanism of materials. The application of the Talbot-Lau interferometer with CT a differential phase contrast tomography is available. Dark-field tomography is used to study individual carbon fiber bundles in carbon fiber reinforced laminates.

  2. Two health information systems to characterize poisoning in Brazil-a descriptive study.

    Science.gov (United States)

    Magalhães, Andrea Franco Amoras; Caldas, Eloisa Dutra

    2018-03-02

    Poisoning is a worldwide public health problem that involves individuals of all ages and a wide range of chemicals. This study investigated the data from two health information systems to characterize poisoning events in the Federal District (DF), Brazil. Data related to the period from 2009 to 2013 were obtained from the poison information center (Centro de Informação Toxicológica, CIT) and the Notifiable Diseases Information System (Sistema Nacional de Agravos de Notificação, SINAN) of the DF. A total of 3622 cases were reported to CIT-DF and 5702 cases to SINAN-DF. Most of the cases in CIT-DF (53%) occurred with children up to 9 years old, while this corresponded to 33.9% in SINAN-DF. Unintentional poisoning was the main circumstance involved in the cases. Pharmaceuticals were the main agent (44.3-47.1% of the cases), mainly clonazepan and paracetamol, and pesticides the most fatal (2.4% fatality rate). Out of the 47 fatal cases reported to the systems, only four were reported to both; six cases occurred with children up to 6 years. Under-reporting and missing information were identified in both systems, but the data were complementary to describe the epidemiology of poisoning cases in the DF.

  3. Aromatic Fused [30] Heteroannulenes with NIR Absorption and NIR Emission: Synthesis, Characterization, and Excited-State Dynamics.

    Science.gov (United States)

    Mallick, Abhijit; Oh, Juwon; Kim, Dongho; Rath, Harapriya

    2016-06-06

    Two hitherto unknown planar aromatic [30] fused heterocyclic macrocycles (1.1.0.1.1.0), with NIR absorption in free-base form and protonation-induced enhanced NIR emission, have been synthesized from easy to make precursors. The induced correspondence of fusion on the macrocyclic structure, electronic absorption, and emission spectra have been highlighted. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Molecular evidence and physiological characterization of iron absorption in isolated enterocytes of rainbow trout (Oncorhynchus mykiss): Implications for dietary cadmium and lead absorption

    International Nuclear Information System (INIS)

    Kwong, Raymond W.M.; Andres, Jose A.; Niyogi, Som

    2010-01-01

    Recent studies suggested the probable involvement of an apical iron (Fe 2+ ) transporter, the divalent metal transporter-1 (DMT1), in the uptake of several divalent metals in fish. The present study examined the gastrointestinal expression of the DMT1 gene, and investigated the kinetics of Fe 2+ uptake and its interactions with cadmium and lead in isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss). The expressions of two DMT1 isoforms (Nramp-β and -γ) were recorded along the entire gastrointestinal tract of fish as well as in the enterocytes. Fe 2+ uptake in isolated enterocytes was saturable and sensitive to the proton gradient and membrane potential, suggesting DMT1-mediated transport. Both cadmium and lead inhibited Fe 2+ uptake in isolated enterocytes in a concentration-dependent manner, and lead appeared to be a stronger inhibitor than cadmium. The kinetic characterization of Fe 2+ uptake revealed that the apparent affinity of uptake was significantly decreased (increased K m ) in the presence of either cadmium or lead, whereas the maximum uptake rate (J max ) remained unchanged-indicating that the interaction between Fe 2+ and cadmium or lead is competitive in nature. Overall, our study suggests that the uptake of dietary cadmium and lead may occur via the iron-transporting pathway in fish.

  5. Molecular evidence and physiological characterization of iron absorption in isolated enterocytes of rainbow trout (Oncorhynchus mykiss): Implications for dietary cadmium and lead absorption

    Energy Technology Data Exchange (ETDEWEB)

    Kwong, Raymond W.M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK., S7N 5B3 (Canada); Andres, Jose A. [Department of Biology, University of Saskatchewan, Saskatoon, SK., S7N 5E2 (Canada); Niyogi, Som, E-mail: som.niyogi@usask.ca [Department of Biology, University of Saskatchewan, Saskatoon, SK., S7N 5E2 (Canada)

    2010-09-01

    Recent studies suggested the probable involvement of an apical iron (Fe{sup 2+}) transporter, the divalent metal transporter-1 (DMT1), in the uptake of several divalent metals in fish. The present study examined the gastrointestinal expression of the DMT1 gene, and investigated the kinetics of Fe{sup 2+} uptake and its interactions with cadmium and lead in isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss). The expressions of two DMT1 isoforms (Nramp-{beta} and -{gamma}) were recorded along the entire gastrointestinal tract of fish as well as in the enterocytes. Fe{sup 2+} uptake in isolated enterocytes was saturable and sensitive to the proton gradient and membrane potential, suggesting DMT1-mediated transport. Both cadmium and lead inhibited Fe{sup 2+} uptake in isolated enterocytes in a concentration-dependent manner, and lead appeared to be a stronger inhibitor than cadmium. The kinetic characterization of Fe{sup 2+} uptake revealed that the apparent affinity of uptake was significantly decreased (increased K{sub m}) in the presence of either cadmium or lead, whereas the maximum uptake rate (J{sub max}) remained unchanged-indicating that the interaction between Fe{sup 2+} and cadmium or lead is competitive in nature. Overall, our study suggests that the uptake of dietary cadmium and lead may occur via the iron-transporting pathway in fish.

  6. Lattice Wind Description and Characterization of Mexico City Local Wind Events in the 2001–2006 Period

    Directory of Open Access Journals (Sweden)

    Alejandro Salcido

    2015-07-01

    Full Text Available Urban transformation and expansion in Mexico City continuously affect its urban morphology, and therefore the modes of wind circulation inside it and their occurrence probabilities. Knowledge on these topics is an important issue for urban planning and for other urban studies, such as air quality assessment. In this paper, using a lattice wind model at a meso-β scale, we develop a simple description and characterization of Mexico City local wind events that occurred during the period 2001–2006, including an estimation of the occurrence probabilities. This region was modeled as a 2D lattice domain of identical cells, and wind conditions in each cell were described by four wind attributes: the horizontal velocity components, divergence, and vorticity. Models of one and four cells were applied to wind data furnished by the meteorological network of the city. Results include the following: Early morning: low intensity winds (75% from N, NW, W and SW (75%, convergent (93%, with a slight predominance of cyclonic vorticity (54%. Morning and early afternoon: winds from N, NE and E (72% with speeds from 0.5 to 3.5 m/s, slight prevailing of convergent winds (51%, and slight predominance of cyclonic vorticity (57%. Late afternoon and night: winds blowing from N, NW, and S (63% with speeds from 1.5 to 3.5 m/s (66%, convergent (90%, and cyclonic (72%.

  7. Characterization of light absorption by chromophoric dissolved organic matter (CDOM) in the upper layer of the Red Sea

    Science.gov (United States)

    Kheireddine, Malika; Ouhssain, Mustapha; Calleja, Maria Ll.; Morán, Xosé Anxelu G.; Sarma, Y. V. B.; Tiwari, Surya P.; Jones, Burton H.

    2018-03-01

    The absorption coefficient of chromophoric dissolved organic matter (CDOM) is a major variable used in developing robust bio-optical models and understanding biogeochemical processes. Over the last decade, the optical properties of CDOM in the open sea have been intensely studied. However, their variations in clear water are poorly documented, particularly in the Red Sea, owing to the absence of in situ measurements. We performed several cruises in the Red Sea to investigate the spatial distribution of the absorption coefficient of CDOM. The spectral absorption coefficients were determined from 400 nm to 740 nm using a WETLabs ac-s hyper-spectral spectrophotometer. In general, we found a latitudinal gradient in the CDOM absorption coefficient at 443 nm (aCDOM(443)) from south to north that is likely influenced by the exchange of water through the strait of Bab-el-Mandeb and the thermohaline circulation of the Red Sea. However, high aCDOM(443) values were observed in the northern Red Sea due to the existence of a sub-mesoscale feature that may induce an increase in phytoplankton production and lead to CDOM production. The aCDOM(443) covaried with the chlorophyll a concentration ([Chl a],) despite a high scatter. Furthermore, the aCDOM(443) for a given [Chl a] concentration was higher than those predicted by global ocean bio-optical models. This study advances our understanding of CDOM concentration in the Red Sea and may help improve the accuracy of the algorithms used to obtain CDOM absorption from ocean color.

  8. Preparation and characterization of novel glass–ceramic tile with microwave absorption properties from iron ore tailings

    International Nuclear Information System (INIS)

    Yao, Rui; Liao, SongYi; Dai, ChangLu; Liu, YuChen; Chen, XiaoYu; Zheng, Feng

    2015-01-01

    A novel glass–ceramic tile consisting of one glass–ceramic layer (GC) attaining microwave absorption properties atop ceramic substrate was prepared through quench-heat treatment route derived from iron ore tailings (IOTs) and commercial raw materials (purity range 73–99%). X-ray diffraction (XRD), SEM, Energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), Physical property measurement system (PPMS) and Vector network analyzer (VNA) measurements were carried out to investigate phase, microstructure, magnetic and microwave absorption aspects of the glass–ceramic layer. Roughly 80.6±1.7 wt% borosilicate glass and 19.4±1.7 wt% spinel ferrite with chemical formula of (Zn 2+ 0.17 Fe 3+ 0.83 )[Fe 3+ 1.17 Fe 2+ 0.06 Ni 2+ 0.77 ]O 4 were found among the tested samples. Absorption of Electromagnetic wave by 3 mm thick glass–ceramic layer at frequency of 2–18 GHz reached peak reflection loss (RL) of −17.61 dB (98.27% microwave absorption) at 10.31 GHz. Altering the thickness of the glass–ceramic layer can meet the requirements of different level of microwave absorption. - Highlights: • Iron ore tailings (IOTs) have been used as one of the main raw materials. • Glass–ceramic tile contains spinel ferrite has been prepared. • The cation distribution of the spinel ferrite has been calculated. • The intrinsic complex permeability and permittivity have been evaluated

  9. Characterization of light absorption by chromophoric dissolved organic matter (CDOM) in the upper layer of the Red Sea

    KAUST Repository

    Kheireddine, Malika

    2018-02-07

    The absorption coefficient of chromophoric dissolved organic matter (CDOM) is a major variable used in developing robust bio‐optical models and understanding biogeochemical processes. Over the last decade, the optical properties of CDOM in the open sea have been intensely studied. However, their variations in clear water are poorly documented, particularly in the Red Sea, owing to the absence of in situ measurements. We performed several cruises in the Red Sea to investigate the spatial distribution of the absorption coefficient of CDOM. The spectral absorption coefficients were determined from 400nm to 740nm using a WETLabs ac-s hyper-spectral spectrophotometer. In general, we found a latitudinal gradient in the CDOM absorption coefficient at 443nm (aCDOM(443)) from south to north that is likely influenced by the exchange of water through the strait of Bab-el-Mandeb and the thermohaline circulation of the Red Sea. However, high aCDOM(443) values were observed in the northern Red Sea due to the existence of a sub-mesoscale feature that may induce an increase in phytoplankton production and lead to CDOM production. The aCDOM(443) covaried with the chlorophyll a concentration ([Chl a],) despite a high scatter. Furthermore, the aCDOM(443) for a given [Chl a] concentration was higher than those predicted by global ocean bio-optical models. This study advances our understanding of CDOM concentration in the Red Sea and may help improve the accuracy of the algorithms used to obtain CDOM absorption from ocean color.

  10. Descriptive attributes used in the characterization of stingless bees (Apidae: Meliponini) in rural populations of the Atlantic forest (Misiones-Argentina).

    Science.gov (United States)

    Zamudio, Fernando; Hilgert, Norma I

    2012-02-13

    Human beings employ a combination of morphological, sensorial, utilitarian, cultural and ecological characters when they identify and classify organisms. Ethnotaxonomy has provided a store of information about the characters cultures employ when they identify and classify a vast diversity of taxonomic groups. Nevertheless, some more research is needed to provide a comparison of the characters employed in the description of taxons, and an analysis of the extent to which those descriptors are represented. Stingless bees constitute a diverse group of social insects that have been widely studied from an ethnobiological perspective due to their utilitarian and cultural importance. The objective of this study is to identify the elements local people consider when characterizing stingless bees, and how important these elements are in the study of local classifications. The methodology used involves semi-structured interviews and trips with the informants to rural areas. Locally known ethnospecies are characterized, descriptive traits and salient criteria used in those characterizations are identified, and the frequency of reference of descriptive traits and salient criteria are estimated. Besides, the descriptive traits used for each ethnospecies are compared, and the contribution of the characterizations as a heuristic strategy in the study of folk classification systems is analyzed. The use of 19 biological descriptors (grouped according to 4 salient criteria) and of comparisons among ethnospecies was found. Results suggest the existence of group and specific descriptors. Researchers identified which ethnospecies are considered similar, how less important traits contribute to descriptions, the relation between specific descriptors and ethnospecies, the presence of cognitive prototypes, and the most relevant salient properties from the emic perspective. The estimated importance of attributes descriptors allowed us to identify the spectrum of salient properties relevant

  11. Ultrasonic absorption

    International Nuclear Information System (INIS)

    Beyer, R.T.

    1985-01-01

    The paper reviews studies of ultrasonic absorption in liquid alkali metals. The experimental methods to measure the absorption coefficients are briefly described. Experimental results reported for the liquid metals: sodium, potassium, rubidium and caesium, at medium temperatures, are presented, as well as data for liquid alloys. Absorption losses due to the presence of an external magnetic field, and the effects of viscosity on the absorption in metals, are both discussed. (U.K.)

  12. Absorption Characterization of Mn-Zr-Substituted La-Sr Hexaferrite Using Open-Circuit and Short-Circuit Approaches in 8.2-18 GHz Frequency Range

    Science.gov (United States)

    Narang, Sukhleen Bindra; Kaur, Pawandeep; Bahel, Shalini; Pubby, Kunal

    2018-01-01

    The present study reports on the microwave absorption characterization of Mn2+-Zr4+ substituted lanthanum strontium ferrites, Sr0.85La0.15(MnZr) x Fe12-2 x O19, where x = 0.0, 0.25, 0.50, 0.75 and 1.0 in the X- and Ku-band. The synthesized ferrites are characterized with regard to their electromagnetic properties such as complex permittivity ( {ɛ^' - jɛ^'' ) and complex permeability ( {μ^' - jμ^'' ) using vector network analysis in the 8.2-18 GHz frequency range. Real and imaginary parts of permittivity decrease with the increase in Mn-Zr concentration due to a reduction in electron hopping conduction and eddy current losses, respectively. Microwave permeability spectra are also affected by the doping. The amplitude of magnetic loss peak increases with the increase in doping except for the x = 1.0 composition. Two commonly used approaches, open-circuit and short-circuit, have been employed for the absorption analysis. The difference in the results of these two techniques is justified on the basis of the reflection mechanism. The presented experimental findings underline the potential of the synthesized compositions with Mn-Zr concentrations x = 0.25, 0.5 and 0.75 in the suppression of electromagnetic reflections and radar signatures.

  13. X-ray Absorption Spectroscopy Characterization of Zn Underpotential Deposition on Au(111) from Phosphate Supporting Electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J R; O' Malley, R L; O' Connell, T J; Vollmer, A; Rayment, T

    2009-12-11

    Zn K-edge X-ray absorption spectroscopy (XAS) has been used to investigate the structure of Zn monolayers prepared on Au(111) electrodes via underpotential deposition (UPD) from phosphate supporting electrolyte. Theoretical modeling of the XAS data indicates that the Zn adatoms adopt a commensurate ({radical}3x{radical}3)R30{sup o} ({mu}{sub sc} = 0.33) adlayer structure and reside within the 3-fold hollow sites of the Au(111) surface. Meanwhile, phosphate counter-ions co-adsorb on the UPD adlayer and bridge between the Zn adatoms in a ({radical}3x{radical}3)R30{sup o} ({mu}{sub sc} = 0.33) configuration, with each phosphorous atom residing above a vacant 3-fold hollow site of the Au(111). Significantly, this surface structure is invariant between the electrochemical potential for UPD adlayer formation and the onset of bulk Zn electrodeposition. Analysis of the Zn K-edge absorption onset also presents the possibility that the Zn adatoms do not fully discharge during the process of UPD, which had been proposed in prior voltammetric studies of the phosphate/Zn(UPD)/Au(111) system.

  14. X-ray absorption spectroscopy characterization of Zn underpotential deposition on Au(1 1 1) from phosphate supporting electrolyte

    International Nuclear Information System (INIS)

    Lee, Jonathan R.I.; O'Malley, Rachel L.; O'Connell, Timothy J.; Vollmer, Antje; Rayment, Trevor

    2010-01-01

    Zn K-edge X-ray absorption spectroscopy (XAS) has been used to investigate the structure of Zn monolayers prepared on Au(1 1 1) electrodes via underpotential deposition (UPD) from phosphate supporting electrolyte. Theoretical modeling of the XAS data indicates that the Zn adatoms adopt a commensurate (√3 x √3)R30 o (θ sc = 0.33) adlayer structure and reside within the 3-fold hollow sites of the Au(1 1 1) surface. Meanwhile, phosphate counter-ions co-adsorb on the UPD adlayer and bridge between the Zn adatoms in a (√3 x √3)R30 o (θ sc = 0.33) configuration, with each phosphorous atom residing above a vacant 3-fold hollow site of the Au(1 1 1). Significantly, this surface structure is invariant between the electrochemical potential for UPD adlayer formation and the onset of bulk Zn electrodeposition. Analysis of the Zn K-edge absorption onset also presents the possibility that the Zn adatoms do not fully discharge during the process of UPD, which had been proposed in prior voltammetric studies of the phosphate/Zn(UPD)/Au(1 1 1) system.

  15. Portable sample preparation and analysis system for micron and sub-micron particle characterization using light scattering and absorption spectroscopy

    Science.gov (United States)

    Stark, Peter C [Los Alamos, NM; Zurek, Eduardo [Barranquilla, CO; Wheat, Jeffrey V [Fort Walton Beach, FL; Dunbar, John M [Santa Fe, NM; Olivares, Jose A [Los Alamos, NM; Garcia-Rubio, Luis H [Temple Terrace, FL; Ward, Michael D [Los Alamos, NM

    2011-07-26

    There is provided a method and device for remote sampling, preparation and optical interrogation of a sample using light scattering and light absorption methods. The portable device is a filtration-based device that removes interfering background particle material from the sample matrix by segregating or filtering the chosen analyte from the sample solution or matrix while allowing the interfering background particles to be pumped out of the device. The segregated analyte is then suspended in a diluent for analysis. The device is capable of calculating an initial concentration of the analyte, as well as diluting the analyte such that reliable optical measurements can be made. Suitable analytes include cells, microorganisms, bioparticles, pathogens and diseases. Sample matrixes include biological fluids such as blood and urine, as well as environmental samples including waste water.

  16. Water Absorption and Thermomechanical Characterization of Extruded Starch/Poly(lactic acid/Agave Bagasse Fiber Bioplastic Composites

    Directory of Open Access Journals (Sweden)

    F. J. Aranda-García

    2015-01-01

    Full Text Available Water absorption and thermomechanical behavior of composites based on thermoplastic starch (TPS are presented in this work, wherein the concentration of agave bagasse fibers (ABF, 0–15 wt% and poly(lactic acid (PLA, 0–30 wt% is varied. Glycerol (G is used as starch (S plasticizer to form TPS. Starch stands as the polymer matrix (70/30 wt/wt, S/G. The results show that TPS hygroscopicity decreases as PLA and fiber content increase. Storage, stress-strain, and flexural moduli increase with PLA and/or agave bagasse fibers (ABF content while impact resistance decreases. The TPS glass transition temperature increases with ABF content and decreases with PLA content. Micrographs of the studied biocomposites show a stratified brittle surface with a rigid fiber fracture.

  17. X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

    This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

  18. Absorption studies

    International Nuclear Information System (INIS)

    Ganatra, R.D.

    1992-01-01

    Absorption studies were once quite popular but hardly anyone does them these days. It is easier to estimate the blood level of the nutrient directly by radioimmunoassay (RIA). However, the information obtained by estimating the blood levels of the nutrients is not the same that can be obtained from the absorption studies. Absorption studies are primarily done to find out whether some of the essential nutrients are absorbed from the gut or not and if they are absorbed, to determine how much is being absorbed. In the advanced countries, these tests were mostly done to detect pernicious anaemia where vitamin B 12 is not absorbed because of the lack of the intrinsic factor in the stomach. In the tropical countries, ''malabsorption syndrome'' is quire common. In this condition, several nutrients like fat, folic acid and vitamin B 12 are not absorbed. It is possible to study absorption of these nutrients by radioisotopic absorption studies

  19. Description and characterization of the melanic morphotype of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae

    Directory of Open Access Journals (Sweden)

    Fernando Braga Stehling Dias

    2014-10-01

    Full Text Available Introduction For the first time we provide the description of the melanic (dark morphotype of Rhodnius nasutus and determine the pattern of genetic inheritance for this characteristic. Methods Dark morph R. nasutus specimens were crossbred with standard (typically patterned R. nasutus. Results We present the first occurrence of the melanic morphotype in the genus Rhodnius. The crossbreeding results demonstrate that the inheritance pattern of this characteristic follows Mendel's simple laws of segregation and an independent assortment of alleles. Conclusions Phenotypic variation of R. nasutus reinforces the heterogeneity found in the Triatominae. Descriptions of new species in this subfamily require rigorous validation criteria.

  20. Characterization of selenium in UO2 spent nuclear fuel by micro X-ray absorption spectroscopy and its thermodynamic stability.

    Science.gov (United States)

    Curti, E; Puranen, A; Grolimund, D; Jädernas, D; Sheptyakov, D; Mesbah, A

    2015-10-01

    Direct disposal of spent nuclear fuel (SNF) in deep geological formations is the preferred option for the final storage of nuclear waste in many countries. In order to assess to which extent radionuclides could be released to the environment, it is of great importance to understand how they are chemically bound in the waste matrix. This is particularly important for long-lived radionuclides such as (79)Se, (129)I, (14)C or (36)Cl, which form poorly sorbing anionic species in water and therefore migrate without significant retardation through argillaceous repository materials and host rocks. We present here X-ray absorption spectroscopic data providing evidence that in the investigated SNF samples selenium is directly bound to U atoms as Se(-II) (selenide) ion, probably replacing oxygen in the cubic UO2 lattice. This result is corroborated by a simple thermodynamic analysis, showing that selenide is the stable form of Se under reactor operation conditions. Because selenide is almost insoluble in water, our data indirectly explain the unexpectedly low release of Se in short-term aqueous leaching experiments, compared to iodine or cesium. These results have a direct impact on safety analyses for potential nuclear waste repository sites, as they justify assuming a small fractional release of selenium in performance assessment calculations.

  1. Characterization of selected solid-state actinide (and related) compounds via Raman and absorption spectrophotometry. Ch. 1

    International Nuclear Information System (INIS)

    Wilmarth, W.R.; Peterson, J.R.

    1991-01-01

    The main focus of this work is on 2 spectroscopic techniques which enable the researcher to obtain information detailing the crystal structure of an actinide compound. This review presents useful cataloging of phonon Raman spectral data for selected binary actinide compounds. Included are the results from the literature with regard to both powder and single crystal data for various actinide oxides and halides. Where relevant data on the actinide compounds were unavailable , data has been included for actinide-related compounds, primarily lanthanide compounds. Another useful spectroscopic probe of crystal structure of an actinide compound is solid-state spectrophotometry. The electronic configurations of the actinide ions give rise to Laporte-forbidden f-f electronic transitions. These 5f electrons, although shielded, are affected by the crystal field about the actinide ion. In the case of a well-defined crystal, this effect is repeated over a long range. The selection rules which give rise to the intensities of these electronic f-f transitions are governed by the crystal symmetry. It has been found that the observed room-temperature absorption spectra of various trivalent actinide ions in different host matrices exhibiting the same crystal structure are reproducible and are, therefore, very dependent on the crystal structure. (author). 57 refs.; 21 figs.; 26 tabs

  2. Characterization of mercury binding onto a novel brominated biomass ash sorbent by X-ray absorption spectroscopy.

    Science.gov (United States)

    Bisson, Teresa M; MacLean, Lachlan C W; Hu, Yongfeng; Xu, Zhenghe

    2012-11-06

    Recent laboratory and field-scale experiments demonstrated the potential for brominated industrial solid waste from biomass combustion (Br-Ash) to be an efficient, cost-effective alternative to activated carbon for capturing mercury from coal-fired power plants. To develop this attractive alternative technology to a commercially sustainable level, a better understanding of mercury capture mechanisms by Br-Ash is required. For this purpose, X-ray absorption fine-structure (XAFS) spectra of Br-Ash were collected at the Hg L(III)-edge, Br K-edge and S K-edge, and analyzed to determine the local bonding environment of mercury atoms. The coordination environment of Hg was compared with that on a commercial brominated activated carbon. Our results indicate that the mercury was captured by chemisorption on both the commercial and biomass ash sorbents; however, the mercury binding environment was different for each sorbent. Mercury was found to bind to the reduced sulfur by the commercial brominated activated carbon, in contrast to mercury binding with carbon and bromine on the brominated biomass ash. Based on the results obtained, a mechanism of Hg capture involving oxidation of elemental Hg followed by binding of the oxidized mercury on the surface of the sorbent near Br was proposed for the brominated biomass ash.

  3. In vitro characterization of ABC transporters involved in the absorption and distribution of liensinine and its analogs.

    Science.gov (United States)

    Yu, Lushan; Shen, Qi; Zhou, Quan; Jiang, Huidi; Bi, Huichang; Huang, Min; Zhou, Hui; Zeng, Su

    2013-11-25

    Lotus plumule, the dried young cotyledon and radicle of the Nelumbo nucifera Gaertn. (Fam. Nymphaeaceae) ripe seed, is a famous Traditional Chinese Medicine to remove heat from the heart, anchor the mind, improve seminal emission, and arrest bleeding for centuries in China. Liensinine and its analogs neferine and isoliensinine are the major active components in lotus plumule. Aim of the study is to investigate the association of liensinine, neferine, and isoliensinine with efflux transporters. Caco-2, MDCK, MDCK-MDR1, and MDCK-MRP2 were used as cell models for the transcellular transport and accumulation studies. The results obtained in Caco-2 cells suggested that P-glycoprotein (P-gp) might be involved in transcellular transport. Cellular accumulation and transport experiments were further performed in MDCK-MDR1 cells. GF120918 and cyclosporine A were found to completely inhibit the efflux, and the net efflux ratios of these alkaloids exhibited saturation over the concentration range. No significant differences in liensinine accumulation and transport were observed between MDCK and MDCK-MRP2 cells. These results demonstrated that liensinine, neferine, and isoliensinine are substrates of P-gp, whereas MRP2 is not involved in the transport process, suggesting that P-gp might be responsible for the absorption and distribution of the 3 alkaloids. © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Structural characterization of vanadium oxide catalysts supported on nanostructured silica SBA-15 using X-ray absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    Walter Anke

    2010-02-01

    Full Text Available Abstract The local structure of vanadium oxide supported on nanostructured SiO2 (VxOy/SBA-15 was investigated by in situ X-ray absorption spectroscopy (XAS. Because the number of potential parameters in XAS data analysis often exceeds the number of "independent" parameters, evaluating the reliability and significance of a particular fitting procedure is mandatory. The number of independent parameters (Nyquist may not be sufficient. Hence, in addition to the number of independent parameters, a novel approach to evaluate the significance of structural fitting parameters in XAS data analysis is introduced. Three samples with different V loadings (i.e. 2.7 wt %, 5.4 wt %, and 10.8 wt % were employed. Thermal treatment in air at 623 K resulted in characteristic structural changes of the V oxide species. Independent of the V loading, the local structure around V centers in dehydrated VxOy/SBA-15 corresponded to an ordered arrangement of adjacent V2O7 units. Moreover, the V2O7 units were found to persist under selective oxidation reaction conditions.

  5. Trace metal characterization and speciation in geothermal effluent by multiple scanning anodic stripping voltammetry and atomic absorption analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, B.R.

    1979-05-25

    Recent studies have shown geothermal power plants to have a significant environmental impact on the ground water of the area. The heavy metals arsenic and mercury are special problems, as both are concentrated by flora and fauna exposed to the effluent waters. Because the toxicity of these and other metallic pollutants present in geothermal effluent depends on the chemical form, or speciation, of the particular metal, any serious study of the environmental impact of a geothermal development should include studies of trace metal speciation, in addition to trace metal concentration. This proposal details a method for determining metal speciation in dilute waters. The method is based on ion-exchange and backed by atomic absorption spectrometry and multiple scanning anodic stripping voltammetry. Special laboratory studies will be performed on mercury, arsenic and selenium speciation in synthetic geothermal water. The method will be applied to three known geothermal areas in Washington and Oregon, with emphasis on the speciation of mercury, arsenic and selenium in these waters. The computer controlled electrochemical instrumentation was built and tested. Using this instrumentation, a new experimental procedure was developed to determine the chemical form (speciation) of metal ions in very dilute solutions (ng/ml). This method was tested on model systems including Pb, Cd, and As with C1/sup -/, CO/sub 3//sup 2 -/ and glycine ligands. Finally, the speciation of lead in a geothermal water was examined and the PbC1/sup +/ complex was observed and quantified.

  6. Nanosuspensions of 10-hydroxycamptothecin that can maintain high and extended supersaturation to enhance oral absorption: preparation, characterization and in vitro/in vivo evaluation

    Science.gov (United States)

    Pu, Xiaohui; Sun, Jin; Han, Jihong; Lian, He; Zhang, Peng; Yan, Zhongtian; He, Zhonggui

    2013-11-01

    The purpose of the study was to prepare and characterize nanosuspensions that can maintain high and extended supersaturation to improve the dissolution and absorption of poorly soluble 10-hydroxycamptothecin (10-HCPT). 10-HCPT oral nanosuspensions (HCPT-Nanosuspensions) were produced on a laboratory-scale by microprecipitation- high pressure homogenization method. The particle morphology and the physical state were studied using transmission electron microscopy, X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC). Supersaturated dissolution tests were carried out with the paddle method. Caco-2 cell experiments were performed to imitate the oral absorption. The in vivo pharmacokinetics studies were undertaken in rats following oral administration. The 10-HCPT nanoparticles were 135 nm in dimension before lyophilization and were claviform or lump in shape. XRPD and DSC both confirmed that a portion of 10-HCPT was present in a crystalline state in nanosuspension. Supersaturated dissolution tests showed HCPT-Nanosuspensions could maintain high supersaturated level for an extended period time. The cell experiment on HCPT-Nanosuspensions showed a significantly higher uptake and greater membrane permeability compared with the other formulations. The pharmacokinetic test exhibited HCPT-Nanosuspensions had a similar pharmacokinetic performance with 10-HCPT solution. In conclusion, highly and extendedly supersaturated HCPT-Nanosuspensions have been prepared which could result in high peak concentration ( C max) and great exposure (AUC) after oral administration.

  7. Nanosuspensions of 10-hydroxycamptothecin that can maintain high and extended supersaturation to enhance oral absorption: preparation, characterization and in vitro/in vivo evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pu, Xiaohui; Sun, Jin, E-mail: sunjin66@21cn.com [Shenyang Pharmaceutical University, Department of Biopharmaceutics, School of Pharmacy (China); Han, Jihong [Keele University, School of Pharmacy and Institute for Science and Technology in Medicine (United Kingdom); Lian, He; Zhang, Peng [Shenyang Pharmaceutical University, Department of Biopharmaceutics, School of Pharmacy (China); Yan, Zhongtian [Nantion Institutes for Food and Drug Control (China); He, Zhonggui, E-mail: hezhgui_student@yahoo.com.cn [Shenyang Pharmaceutical University, Department of Biopharmaceutics, School of Pharmacy (China)

    2013-11-15

    The purpose of the study was to prepare and characterize nanosuspensions that can maintain high and extended supersaturation to improve the dissolution and absorption of poorly soluble 10-hydroxycamptothecin (10-HCPT). 10-HCPT oral nanosuspensions (HCPT-Nanosuspensions) were produced on a laboratory-scale by microprecipitation- high pressure homogenization method. The particle morphology and the physical state were studied using transmission electron microscopy, X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC). Supersaturated dissolution tests were carried out with the paddle method. Caco-2 cell experiments were performed to imitate the oral absorption. The in vivo pharmacokinetics studies were undertaken in rats following oral administration. The 10-HCPT nanoparticles were 135 nm in dimension before lyophilization and were claviform or lump in shape. XRPD and DSC both confirmed that a portion of 10-HCPT was present in a crystalline state in nanosuspension. Supersaturated dissolution tests showed HCPT-Nanosuspensions could maintain high supersaturated level for an extended period time. The cell experiment on HCPT-Nanosuspensions showed a significantly higher uptake and greater membrane permeability compared with the other formulations. The pharmacokinetic test exhibited HCPT-Nanosuspensions had a similar pharmacokinetic performance with 10-HCPT solution. In conclusion, highly and extendedly supersaturated HCPT-Nanosuspensions have been prepared which could result in high peak concentration (C{sub max}) and great exposure (AUC) after oral administration.

  8. Geospatial Absorption and Regional Effects

    Directory of Open Access Journals (Sweden)

    IOAN MAC

    2009-01-01

    Full Text Available The geospatial absorptions are characterized by a specific complexity both in content and in their phenomenological and spatial manifestation fields. Such processes are differentiated according to their specificity to pre-absorption, absorption or post-absorption. The mechanisms that contribute to absorption are extremely numerous: aggregation, extension, diffusion, substitution, resistivity (resilience, stratification, borrowings, etc. Between these mechanisms frequent relations are established determining an amplification of the process and of its regional effects. The installation of the geographic osmosis phenomenon in a given territory (a place for example leads to a homogenization of the geospatial state and to the installation of the regional homogeneity.

  9. Characterization of poly (vinyl alcohol)/poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) polymer blend: structure, optical absorption, electrical and dielectric properties

    Science.gov (United States)

    Sheha, E.; Nasr, Mona; El-Mansy, M. K.

    2013-09-01

    Polymer blends of poly (vinyl alcohol) (PVA) and PEDOT:PSS (poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate)), were prepared by casting from aqueous solution. They were characterized by x-ray diffraction, scanning electron microscopy, differential scanning calorimetery, thermo gravimetric analysis, Fourier transform infrared, ac spectroscopy and optical UV-visible absorption techniques. The thermal analysis did not illustrate significant variations of PVA when blended with different concentrations of PEDOT:PSS. The bulk conductivity of PVA/PEDOT:PSS blend illustrated a two orders increase, while the activation energy reduced from 0.52 to 0.16 eV with an increasing PEDOT:PSS concentration to 4 wt%. In addition, the frequency dependence of conductivity obeyed the power relation σ ˜ ωs, 0.3 PEDOT:PSS concentration, which was attributed to a direct energy band gap, in the range 1.05-1.2 eV, and plasmon-exciton interaction.

  10. Folate absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Folate is the generic term given to numerous compounds of pteroic acid with glutamic acid. Knowledge of absorption is limited because of the complexities introduced by the variety of compounds and because of the inadequacy of investigational methods. Two assay methods are in use, namely microbiological and radioactive. Techniques used to study absorption include measurement of urinary excretion, serum concentration, faecal excretion, intestinal perfusion, and haematological response. It is probably necessary to test absorption of both pteroylmonoglutamic acid and one or more polyglutamates, and such tests would be facilitated by availability of synthesized compounds labelled with radioactive tracers at specifically selected sites. (author)

  11. Characterization of microwave plasma in a multicusp using 2D emission based tomography: Bessel modes and wave absorption

    Science.gov (United States)

    Rathore, Kavita; Bhattacharjee, Sudeep; Munshi, Prabhat

    2017-06-01

    A tomographic method based on the Fourier transform is used for characterizing a microwave plasma in a multicusp (MC), in order to obtain 2D distribution of plasma emissions, plasma (electron) density (Ne) and temperature (Te). The microwave plasma in the MC is characterized as a function of microwave power, gas pressure, and axial distance. The experimentally obtained 2D emission profiles show that the plasma emissions are generated in a circular ring shape. There are usually two bright rings, one at the plasma core and another near the boundary. The experimental results are validated using a numerical code that solves Maxwell's equations inside a waveguide filled with a plasma in a magnetic field, with collisions included. It is inferred that the dark and bright circular ring patterns are a result of superposition of Bessel modes (TE11 and TE21) of the wave electric field inside the plasma filled MC, which are in reasonable agreement with the plasma emission profiles. The tomographically obtained Ne and Te profiles indicate higher densities in the plasma core (˜1010 cm-3) and enhanced electron temperature in the ECR region (˜13 eV), which are in agreement with earlier results using a Langmuir probe and optical emission spectroscopy (OES) diagnostics.

  12. Narrative absorption

    DEFF Research Database (Denmark)

    Narrative Absorption brings together research from the social sciences and Humanities to solve a number of mysteries: Most of us will have had those moments, of being totally absorbed in a book, a movie, or computer game. Typically we do not have any idea about how we ended up in such a state. Nor...... do we fully realize how we might have changed as we return for the fictional worlds we have visited. The feeling of being absorbed is one of the most illusive and transient feelings, but also one that motivates audiences to spend considerable amounts of time in narrative worlds, and one...... that is central to our understanding of the effects of narratives on beliefs and behavior. Key specialists inform the reader of this book about the nature of the peculiar state of consciousness during episodes of absorption, the perception of absorption in history, the role of absorption in meaningful experiences...

  13. Description and characterization of the novel hyperthermia- and thermoablation-system MFHregistered300F for clinical magnetic fluid hyperthermia

    International Nuclear Information System (INIS)

    Gneveckow, Uwe; Jordan, Andreas; Scholz, Regina; Bruess, Volker; Waldoefner, Norbert; Ricke, Jens; Feussner, Annelie; Hildebrandt, Bert; Rau, Beate; Wust, Peter

    2004-01-01

    Magnetic fluid hyperthermia (MFH) is a new approach to deposit heat power in deep tissues by overcoming limitations of conventional heat treatments. After infiltration of the target tissue with nanosized magnetic particles, the power of an alternating magnetic field is transformed into heat. The combination of the 100 kHz magnetic field applicator MFH registered 300F and the magnetofluid (MF), which both are designed for medical use, is investigated with respect to its dosage recommendations and clinical applicability. We found a magnetic field strength of up to 18 kA/m in a cylindrical treatment area of 20 cm diameter and aperture height up to 300 mm. The specific absorption rate (SAR) can be controlled directly by the magnetic field strength during the treatment. The relationship between magnetic field strength and the iron normalized SAR (SAR Fe ) is only slightly depending on the concentration of the MF and can be used for planning the target SAR. The achievable energy absorption rates of the MF distributed in the tissue is sufficient for either hyperthermia or thermoablation. The fluid has a visible contrast in therapeutic concentrations on a CT scanner and can be detected down to 0.01 g/l Fe in the MRI. The system has proved its capability and practicability for heat treatment in deep regions of the human body

  14. Speciation and characterization of arsenic in gold ores and cyanidation tailings using X-ray absorption spectroscopy

    Science.gov (United States)

    Paktunc, D.; Foster, A.; Heald, S.; Laflamme, G.

    2004-01-01

    The knowledge of mineralogy and molecular structure of As is needed to better understand the stability of As in wastes resulting from processing of gold ores. In this study, optical microscopy, scanning electron microscopy, electron microprobe, X-ray diffraction and X-ray absorption fine structure (XAFS) spectroscopy (including both XANES and EXAFS regimes) were employed to determine the mineralogical composition and local coordination environment of As in gold ores and process tailings from bench-scale tests designed to mimic a common plant practice. Arsenic-bearing minerals identified in the ores and tailings include iron (III) oxyhydroxides, scorodite (FeAsO4??2H2O), ferric arsenates, arseniosiderite (Ca2Fe3 (AsO4)3O2??3H2O), Ca-Fe arsenates, pharmacosiderite (KFe4 (AsO4)3(OH)4??6-7H2O), jarosite (K2Fe6(SO4)4 (OH)12) and arsenopyrite (FeAsS). Iron (III) oxyhydroxides contain variable levels of As from trace to about 22 wt% and Ca up to approximately 9 wt%. Finely ground ore and tailings samples were examined by bulk XAFS and selected mineral grains were analyzed by microfocused XAFS (micro-EXAFS) spectroscopy to reconcile the ambiguities of multiple As sources in the complex bulk EXAFS spectra. XANES spectra indicated that As occurs as As5+in all the samples. Micro-EXAFS spectra of individual iron (III) oxyhydroxide grains with varying As concentrations point to inner-sphere bidentate-binuclear arsenate complexes as the predominant form of As. There are indications for the presence of a second Fe shell corresponding to bidentate-mononuclear arrangement. Iron (III) oxyhydroxides with high As concentrations corresponding to maximum adsorption densities probably occur as nanoparticles. The discovery of Ca atoms around As in iron (III) oxyhydroxides at interatomic distances of 4.14-4.17 A?? and the coordination numbers suggest the formation of arseniosiderite-like nanoclusters by coprecipitation rather than simple adsorption of Ca onto iron (III) oxyhydroxides

  15. Description and characterization of system for external insulation and retrofitting for Denmark with emphasis on the thermal performance

    Energy Technology Data Exchange (ETDEWEB)

    Rudbeck, C.; Svendsen, S.

    1999-06-01

    Lately there has been quite a large focus on retrofitting of the Danish buildings. The retrofitting of the building is done in order to solve one or more of the following problems: bad indoor climate, large use of energy for heating, insufficient durability or architectural unsatisfactory. In order to solve these problems insulation is often part of the retrofitting. As internal insulation has many disadvantages with regards to heat and moisture only systems for external insulation will be mentioned here. As there are several different systems for external insulation, each with different properties, there is a need for a systematic approach when the building designer chooses which system should be used on the building which is to be retrofitted. All 12 systems are described using a format that subdivides the information from the producers into description of the system, drawings showing the system and index-numbers regarding heat, moisture and economy. From the 12 systems descriptions it is seen that the investment cost for most of the system used for retrofitting and external insulation is almost equal. The parameters which separates the systems from each other is the maintenance cost and the cost of the heat transmission loss through the retrofitting-system. According to the calculations there is not one system which performs better than the others when changing the parameters. The choice of a system for retrofitting depends (as far as total economy is concerned) mainly on the maintenance cost (which is difficult to predict) and the energy cost. Likewise the life time of the retrofitting system does also influence the total economy. Apart from these three factors aesthetics should also be taken into account when choosing a retrofitting system but this aspect has not been dealt with in this report. (EHS)

  16. SAROTA: application of specific absorption rate (SAR) and over-the-air (OTA) data for the characterization of the real-life exposure due to mobile phones

    International Nuclear Information System (INIS)

    Monebhurrun, Vikass

    2013-01-01

    The RF exposure level of a mobile phone is quantified by the measurement of the specific absorption rate (SAR) under laboratory conditions. The SAR which is measured while the mobile phone is operated at maximum power level does not reflect the real-life exposure scenario since the mobile phone typically re-adjusts its power level and frequency depending on the quality of the communication link with the nearest base station. The choice of a low RF exposure device based on the comparison of the relative SAR values of mobile phones can be misleading. The real-life RF exposure also depends on the over-the-air (OTA) performance of the mobile phone. Taken independently, the two sets of data do not allow a straightforward comparison of the global RF performance amongst mobile phones. A unique and simple parameter denoted as the SAROTA index is proposed for the characterization of mobile phones with regard to both RF exposure and OTA performance. The SAROTA index provides the real-life exposure index of the mobile phone.

  17. Description and characterization of BRPR series S-0, S-1, S-2, S-3, and S-4 demonstration fuel rods

    International Nuclear Information System (INIS)

    Welty, R.K.

    1981-07-01

    This report describes the process development, fabrication, and pre-irradiation characterization of the demonstration fuel rods for irradiation in the Big Rock Point Reactor as part of the DOE-sponsored Fuel Performance Improvement Program (FPIP). The fuel rods represent advanced designs that are expected to exhibit improved performance with respect to pellet-cladding-interaction and the attainment of extended burnup. Whereas other design variations are described, the primary fuel concepts being evaluated as part of the FPIP are an annular-coated-pressurized design and, at a more modest level, a sphere-pac design. A solid-pellet reference design provides the basis for comparing irradiation behavior

  18. Characterization of biocenoses in the storage reservoirs of liquid radioactive wastes of Mayak PA. Initial descriptive report

    International Nuclear Information System (INIS)

    Pryakhin, E.A.; Mokrov, Yu.G.; Tryapitsina, G.A.; Ivanov, I.A.; Osipov, D.I.; Atamanyuk, N.I.; Deryabina, L.V.; Shaposhnikova, I.A.; Shishkina, E.A.; Obvintseva, N.A.; Egoreichenkov, E.A.; Styazhkina, E.V.; Osipova, O.F.; Mogilnikova, N.I.; Andreev, S.S.; Tarasov, O.V.; Geras'kin, S.A.; Trapeznikov, A.V.; Akleyev, A.V.

    2016-01-01

    As a result of operation of the Mayak Production Association (Mayak PA), Chelyabinsk Oblast, Russia, an enterprise for production and separation of weapon-grade plutonium in the Soviet Union, ecosystems of a number of water bodies have been radioactively contaminated. The article presents information about the current state of ecosystems of 6 special industrial storage reservoirs of liquid radioactive waste from Mayak PA: reservoirs R-3, R-4, R-9, R-10, R-11 and R-17. At present the excess of the radionuclide content in the water of the studied reservoirs and comparison reservoirs (Shershnyovskoye and Beloyarskoye reservoirs) is 9 orders of magnitude for 90 Sr and 137 Cs, and 6 orders of magnitude for alpha-emitting radionuclides. According to the level of radioactive contamination, the reservoirs of the Mayak PA could be arranged in the ascending order as follows: R-11, R-10, R-4, R-3, R-17 and R-9. In 2007–2012 research of the status of the biocenoses of these reservoirs in terms of phytoplankton, zooplankton, bacterioplankton, zoobenthos, aquatic plants, ichthyofauna, avifauna parameters was performed. The conducted studies revealed decrease in species diversity in reservoirs with the highest levels of radioactive and chemical contamination. This article is an initial descriptive report on the status of the biocenoses of radioactively contaminated reservoirs of the Mayak PA, and is the first article in a series of publications devoted to the studies of the reaction of biocenoses of the fresh-water reservoirs of the Mayak PA to a combination of natural and man-made factors, including chronic radiation exposure. - Highlights: • The current state of storage reservoirs of liquid radioactive waste of the Mayak Production Association is presented. • Radionuclides contents in water and sediments of the reservoirs of Mayak PA are presented. • The status of the major ecological groups of hydrobionts of the given reservoirs is described.

  19. Characterization of Functionalized Self-Assembled Monolayers and Surface-Attached Interlocking Molecules Using Near-Edge X-ray Absorption Fine Structure Spectroscopy

    International Nuclear Information System (INIS)

    Willey, T; Willey, T

    2004-01-01

    Quantitative knowledge of the fundamental structure and substrate binding, as well as the direct measurement of conformational changes, are essential to the development of self-assembled monolayers (SAMs) and surface-attached interlocking molecules, catenanes and rotaxanes. These monolayers are vital to development of nano-mechanical, molecular electronic, and biological/chemical sensor applications. This dissertation investigates properties of functionalized SAMs in sulfur-gold based adsorbed molecular monolayers using quantitative spectroscopic techniques including near-edge x-ray absorption fine structure spectroscopy (NEXAFS) and x-ray photoelectron spectroscopy (XPS). The stability of the gold-thiolate interface is addressed. A simple model SAM consisting of dodecanethiol adsorbed on Au(111) degrades significantly in less than 24 hours under ambient laboratory air. S 2p and O 1s XPS show the gold-bound thiolates oxidize to sulfinates and sulfonates. A reduction of organic material on the surface and a decrease in order are observed as the layer degrades. The effect of the carboxyl vs. carboxylate functionalization on SAM structure is investigated. Carboxyl-terminated layers consisting of long alkyl-chain thiols vs. thioctic acid with short, sterically separated, alkyl groups are compared and contrasted. NEXAFS shows a conformational change, or chemical switchability, with carboxyl groups tilted over and carboxylate endgroups more upright. Surface-attached loops and simple surface-attached rotaxanes are quantitatively characterized, and preparation conditions that lead to desired films are outlined. A dithiol is often insufficient to form a molecular species bound at each end to the substrate, while a structurally related disulfide-containing polymer yields surface-attached loops. Similarly, spectroscopic techniques show the successful production of a simple, surface-attached rotaxane that requires a ''molecular riveting'' step to hold the mechanically attached

  20. Development and Characterization of a High Speed Mid-IR Tunable Diode Laser Absorption Spectrometer for CO and CO2 Detection in Detonation Events

    Science.gov (United States)

    2014-03-27

    fundamental equation for absorption spectroscopy follows from the Beer - Lambert Law , ( It I0 )v = e− S PxiφνL, (2.1) where S is the line-strength of a...data in frequency space, the Beer - Lambert law was applied in order to express the data in terms of absorption coefficient. This task was accomplished...according to an intensity where no absorption occurs according to Beer’s Law . Furthermore, the plots now focus on the regions of interest. For an

  1. Characterization of 618-11 solid waste burial ground, disposed waste, and description of the waste generating facilities

    Energy Technology Data Exchange (ETDEWEB)

    Hladek, K.L.

    1997-10-07

    The 618-11 (Wye or 318-11) burial ground received transuranic (TRTJ) and mixed fission solid waste from March 9, 1962, through October 2, 1962. It was then closed for 11 months so additional burial facilities could be added. The burial ground was reopened on September 16, 1963, and continued operating until it was closed permanently on December 31, 1967. The burial ground received wastes from all of the 300 Area radioactive material handling facilities. The purpose of this document is to characterize the 618-11 solid waste burial ground by describing the site, burial practices, the disposed wastes, and the waste generating facilities. This document provides information showing that kilogram quantities of plutonium were disposed to the drum storage units and caissons, making them transuranic (TRU). Also, kilogram quantities of plutonium and other TRU wastes were disposed to the three trenches, which were previously thought to contain non-TRU wastes. The site burial facilities (trenches, caissons, and drum storage units) should be classified as TRU and the site plutonium inventory maintained at five kilograms. Other fissile wastes were also disposed to the site. Additionally, thousands of curies of mixed fission products were also disposed to the trenches, caissons, and drum storage units. Most of the fission products have decayed over several half-lives, and are at more tolerable levels. Of greater concern, because of their release potential, are TRU radionuclides, Pu-238, Pu-240, and Np-237. TRU radionuclides also included slightly enriched 0.95 and 1.25% U-231 from N-Reactor fuel, which add to the fissile content. The 618-11 burial ground is located approximately 100 meters due west of Washington Nuclear Plant No. 2. The burial ground consists of three trenches, approximately 900 feet long, 25 feet deep, and 50 feet wide, running east-west. The trenches constitute 75% of the site area. There are 50 drum storage units (five 55-gallon steel drums welded together

  2. Characterization of 618-11 solid waste burial ground, disposed waste, and description of the waste generating facilities

    International Nuclear Information System (INIS)

    Hladek, K.L.

    1997-01-01

    The 618-11 (Wye or 318-11) burial ground received transuranic (TRTJ) and mixed fission solid waste from March 9, 1962, through October 2, 1962. It was then closed for 11 months so additional burial facilities could be added. The burial ground was reopened on September 16, 1963, and continued operating until it was closed permanently on December 31, 1967. The burial ground received wastes from all of the 300 Area radioactive material handling facilities. The purpose of this document is to characterize the 618-11 solid waste burial ground by describing the site, burial practices, the disposed wastes, and the waste generating facilities. This document provides information showing that kilogram quantities of plutonium were disposed to the drum storage units and caissons, making them transuranic (TRU). Also, kilogram quantities of plutonium and other TRU wastes were disposed to the three trenches, which were previously thought to contain non-TRU wastes. The site burial facilities (trenches, caissons, and drum storage units) should be classified as TRU and the site plutonium inventory maintained at five kilograms. Other fissile wastes were also disposed to the site. Additionally, thousands of curies of mixed fission products were also disposed to the trenches, caissons, and drum storage units. Most of the fission products have decayed over several half-lives, and are at more tolerable levels. Of greater concern, because of their release potential, are TRU radionuclides, Pu-238, Pu-240, and Np-237. TRU radionuclides also included slightly enriched 0.95 and 1.25% U-231 from N-Reactor fuel, which add to the fissile content. The 618-11 burial ground is located approximately 100 meters due west of Washington Nuclear Plant No. 2. The burial ground consists of three trenches, approximately 900 feet long, 25 feet deep, and 50 feet wide, running east-west. The trenches constitute 75% of the site area. There are 50 drum storage units (five 55-gallon steel drums welded together

  3. Descriptive Research

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    2003-01-01

    Descriptive research is described by Lathom-Radocy and Radocy (1995) to include Survey research, ex post facto research, case studies and developmental studies. Descriptive research also includes a review of the literature in order to provide both quantitative and qualitative evidence of the effect...... starts will allow effect size calculations to be made in order to evaluate effect over time. Given the difficulties in undertaking controlled experimental studies in the creative arts therapies, descriptive research methods offer a way of quantifying effect through descriptive statistical analysis...

  4. Characterization of Key Factors of Anchovy (Engraulis japonicus) Meat in the Nanoparticle-Mediated Enhancement of Non-Heme Iron Absorption.

    Science.gov (United States)

    Zou, Yaqun; Zhao, Liang; Feng, Guangxin; Miao, Yu; Wu, Haohao; Zeng, Mingyong

    2017-12-27

    Anchovy (Engraulis japonicus) meat (AM) has been shown to promote nonheme iron absorption via a ferric oxyhydroxide nanoparticle (FeONP)-mediated mechanism. Here, formulation modifications of an egg-white-based AIN-93G diet with AM fractions resulted hemoglobin regeneration efficiencies in anemic rats following an order control (23.69 ± 3.99%) iron enriched in proximal-small-intestinal contents by these AM fractions. The calcein-fluorescence-quenching assay in polarized Caco-2 cells revealed good iron absorption from FeONPs coated with AM peptides, l-α-phosphatidylcholine, l-α-lysophosphatidylcholine, and chondroitin sulfate, with the latter two disfavoring endocytosis thereby inducing relatively weaker iron absorption. These results suggest peptides, phospholipids, and mucopolysaccharides released during AM digestion are key factors promoting nonheme iron absorption.

  5. Descriptive attributes used in the characterization of stingless bees (Apidae: Meliponini) in rural populations of the Atlantic forest (Misiones-Argentina)

    Science.gov (United States)

    2012-01-01

    Abstract Background Human beings employ a combination of morphological, sensorial, utilitarian, cultural and ecological characters when they identify and classify organisms. Ethnotaxonomy has provided a store of information about the characters cultures employ when they identify and classify a vast diversity of taxonomic groups. Nevertheless, some more research is needed to provide a comparison of the characters employed in the description of taxons, and an analysis of the extent to which those descriptors are represented. Stingless bees constitute a diverse group of social insects that have been widely studied from an ethnobiological perspective due to their utilitarian and cultural importance. The objective of this study is to identify the elements local people consider when characterizing stingless bees, and how important these elements are in the study of local classifications. Methods The methodology used involves semi-structured interviews and trips with the informants to rural areas. Locally known ethnospecies are characterized, descriptive traits and salient criteria used in those characterizations are identified, and the frequency of reference of descriptive traits and salient criteria are estimated. Besides, the descriptive traits used for each ethnospecies are compared, and the contribution of the characterizations as a heuristic strategy in the study of folk classification systems is analyzed. Results The use of 19 biological descriptors (grouped according to 4 salient criteria) and of comparisons among ethnospecies was found. Results suggest the existence of group and specific descriptors. Researchers identified which ethnospecies are considered similar, how less important traits contribute to descriptions, the relation between specific descriptors and ethnospecies, the presence of cognitive prototypes, and the most relevant salient properties from the emic perspective. Conclusions The estimated importance of attributes descriptors allowed us to

  6. Descriptive attributes used in the characterization of stingless bees (Apidae: Meliponini in rural populations of the Atlantic forest (Misiones-Argentina

    Directory of Open Access Journals (Sweden)

    Zamudio Fernando

    2012-02-01

    Full Text Available Abstract Background Human beings employ a combination of morphological, sensorial, utilitarian, cultural and ecological characters when they identify and classify organisms. Ethnotaxonomy has provided a store of information about the characters cultures employ when they identify and classify a vast diversity of taxonomic groups. Nevertheless, some more research is needed to provide a comparison of the characters employed in the description of taxons, and an analysis of the extent to which those descriptors are represented. Stingless bees constitute a diverse group of social insects that have been widely studied from an ethnobiological perspective due to their utilitarian and cultural importance. The objective of this study is to identify the elements local people consider when characterizing stingless bees, and how important these elements are in the study of local classifications. Methods The methodology used involves semi-structured interviews and trips with the informants to rural areas. Locally known ethnospecies are characterized, descriptive traits and salient criteria used in those characterizations are identified, and the frequency of reference of descriptive traits and salient criteria are estimated. Besides, the descriptive traits used for each ethnospecies are compared, and the contribution of the characterizations as a heuristic strategy in the study of folk classification systems is analyzed. Results The use of 19 biological descriptors (grouped according to 4 salient criteria and of comparisons among ethnospecies was found. Results suggest the existence of group and specific descriptors. Researchers identified which ethnospecies are considered similar, how less important traits contribute to descriptions, the relation between specific descriptors and ethnospecies, the presence of cognitive prototypes, and the most relevant salient properties from the emic perspective. Conclusions The estimated importance of attributes descriptors

  7. Preparation and characterization of Ba0.2Sr0.2La0.6MnO3 nanoparticles and investigation of size & shape effect on microwave absorption

    Science.gov (United States)

    Peymanfar, Reza; Javanshir, Shahrzad

    2017-06-01

    In this paper, the design and characterization of a radar absorbing material (RAM) was investigated at microwave frequency. Ba0.2Sr0.2La0.6MnO3 magnetic nanoparticles was synthesized thru a facile hydrothermal method in the presence of polymethyl methacrylate (PMMA) and the possibility of shape and size-controlled synthesis of nanoparticles (NPs) over the range 15-50 Nm was also explored. Afterward, the effect of shape and size of the synthesized Ba0.2Sr0.2La0.6MnO3 NPs on microwave absorption properties was investigated in KU-band. The crystal structures and morphology of as-synthesized nanoparticles were characterized and confirmed by FESEM, XRD, VSM, FTIR analysis. The RAM samples were prepared by dispersion of magnetic NPs in silicone rubber in an ultrasonic bath. The maximum reflection loss (RL) values NPs were 12.04 dB at 14.82 GHz and a broad absorption band (over 1.22 GHz) with RL values <-10 dB are obtained and the maximum reflection loss (RL) values of decrease and shaped NPs were 22.36 dB at 14.78 GHz and a broad absorption band (over 2.67 GHz) with RL values <-10 dB are obtained. The results indicated that the particle size and shape play a major role on the absorption properties of the composites in the 12.4-18 GHz frequency range. It is observed that microwave absorption properties increased with the decrease in average particle size of NPs.

  8. A new hydride generator for the determination of volatile elements by atomic absorption spectrophotometry

    International Nuclear Information System (INIS)

    Kersabiec, A.M. de

    1979-01-01

    The production of hydrides in order to use them for analysis by atomic absorption spectrophotometry depends on many parameters. A new apparatus has been designed for this specific operation. It is characterized by a reaction chamber with variable size and by appliances for regulation and control of the physical conditions of operation. Properties are both methodological studies and utilization in large scale analysis. The entire description of the apparatus is completed by an analytical study [fr

  9. A novel lead imprinted polymer as the selective solid phase for extraction and trace detection of lead ions by flame atomic absorption spectrophotometry: Synthesis, characterization and analytical application

    Directory of Open Access Journals (Sweden)

    Homeira Ebrahimzadeh

    2017-05-01

    Full Text Available A novel ion imprinted polymer as the selective solid phase combined with flame atomic absorption spectrometry (FAAS was applied for preconcentration and determination of lead in real samples. In the first step, Pb(II-IIP was synthesized by copolymerization of 2-vinyl pyridine as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, 2,2-azobisisobutyronitrile as the initiator that imprinted with Pb(II as the template ion, 2-amino pyridine as the ligand. Subsequently, the imprinted Pb(II was completely removed by leaching the dried and powdered imprinted polymer with HCl (2 mol L−1. This polymer was characterized by Fourier Transform Infrared (FT-IR spectrometer. The effect of different variables on the extraction efficiency such as type and volume of eluent for extraction, solution’s pH for adsorption, sorption and desorption times was evaluated. Under the optimum conditions: type of eluent, HCl (2 mol L−1; volume of eluent, 5 mL; solution’s pH for sorption, 5; sorption time, 90 min; desorption time, 125 min and breakthrough volume of 750 mL were obtained. Preconcentration factor of the method was about 150. The limit of detection was obtained 0.75 μg L−1 and a dynamic linear range (DLR of 3–150 μg L−1 was found. The maximum sorption retention capacity of Pb(II ions on the imprinted polymer was 85.6 mg g−1. The prepared ion-imprinted polymer particles have an increased selectivity toward Pb(II ions over a range of competing metal ions with the same charge and similar ionic radius. Performance of the present method was evaluated for extraction and determination of Pb(II in water samples at microgram per liter concentration and satisfactory results were obtained (RSD = 2.7%.

  10. Exploiting the P L2,3 absorption edge for optics: spectroscopic and structural characterization of cubic boron phosphide thin films

    NARCIS (Netherlands)

    Huber, Sebastiaan; Medvedev, Viacheslav; Meyer-Ilse, J.; Gullikson, E.; Padavala, B.; Edgar, J.H.; Sturm, Jacobus Marinus; van de Kruijs, Robbert Wilhelmus Elisabeth; Prendergast, D.; Bijkerk, Frederik

    2016-01-01

    The transmission of cubic boron phosphide (c-BP) thin films, prepared by chemical vapor deposition (CVD), was evaluated near the phosphorous L2,3 and boron K absorption edge. The c-BP films were analyzed with transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray

  11. Preparation and characterization of Ba{sub 0.2}Sr{sub 0.2}La{sub 0.6}MnO{sub 3} nanoparticles and investigation of size & shape effect on microwave absorption

    Energy Technology Data Exchange (ETDEWEB)

    Peymanfar, Reza; Javanshir, Shahrzad, E-mail: shjavan@iust.ac.ir

    2017-06-15

    Highlights: • Hydrothermal synthesis of Ba{sub 0.2}Sr{sub 0.2}La{sub 0.6}MnO{sub 3} performed in the presence of PMMA. • Shape and size-controlled synthesis of NPs over the range 15–50 Nm was explored. • Investigation of shape and size effect of NPs on microwave absorption properties. - Abstract: In this paper, the design and characterization of a radar absorbing material (RAM) was investigated at microwave frequency. Ba{sub 0.2}Sr{sub 0.2}La{sub 0.6}MnO{sub 3} magnetic nanoparticles was synthesized thru a facile hydrothermal method in the presence of polymethyl methacrylate (PMMA) and the possibility of shape and size-controlled synthesis of nanoparticles (NPs) over the range 15–50 Nm was also explored. Afterward, the effect of shape and size of the synthesized Ba{sub 0.2}Sr{sub 0.2}La{sub 0.6}MnO{sub 3} NPs on microwave absorption properties was investigated in KU-band. The crystal structures and morphology of as-synthesized nanoparticles were characterized and confirmed by FESEM, XRD, VSM, FTIR analysis. The RAM samples were prepared by dispersion of magnetic NPs in silicone rubber in an ultrasonic bath. The maximum reflection loss (RL) values NPs were 12.04 dB at 14.82 GHz and a broad absorption band (over 1.22 GHz) with RL values <−10 dB are obtained and the maximum reflection loss (RL) values of decrease and shaped NPs were 22.36 dB at 14.78 GHz and a broad absorption band (over 2.67 GHz) with RL values <−10 dB are obtained. The results indicated that the particle size and shape play a major role on the absorption properties of the composites in the 12.4–18 GHz frequency range. It is observed that microwave absorption properties increased with the decrease in average particle size of NPs.

  12. First combined total reflection X-ray fluorescence and grazing incidence X-ray absorption spectroscopy characterization of aeolian dust archived in Antarctica and Alpine deep ice cores

    Energy Technology Data Exchange (ETDEWEB)

    Cibin, G. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxon OX110DE (United Kingdom); IMONT/EIM, Ente Italiano della Montagna, P.za dei Caprettari 70, 00176 Roma (Italy); Universita' degli Studi di Roma Tre, Dipartimento di Scienze Geologiche, L.go S. Leonardo Murialdo 1, 00146 Roma (Italy)], E-mail: giannantonio.cibin@diamond.ac.uk; Marcelli, A. [INFN - Laboratori Nazionali di Frascati, P.O. Box 13, 00044 Frascati (Roma) (Italy); Maggi, V. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Sala, M. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Universita degli Studi di Milano, Dipartimento di Scienze della Terra ' A. Desio' , Sez. Mineralogia, Via Mangiagalli 34, 20133 Milano (Italy); Marino, F.; Delmonte, B. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Albani, S. [Universita degli Studi di Milano-Bicocca, Dipartimento di Scienze dell' Ambiente e del Territorio, Piazza della Scienza 1, 20126 Milano (Italy); Universita degli Studi di Siena, Dottorato in Scienze Polari, via Laterina 8, 53100 Siena (Italy); Pignotti, S. [IMONT/EIM, Ente Italiano della Montagna, P.za dei Caprettari 70, 00176 Roma (Italy)

    2008-12-15

    Aeolian mineral dust archived in polar and mid latitude ice cores represents a precious proxy for assessing environmental and climatic variations at different timescales. In this respect, the identification of dust mineralogy plays a key role. In this work we performed the first preliminary X-ray absorption spectroscopy (XAS) experiments on mineral dust particles extracted from Antarctic and from Alpine firn cores using grazing incidence geometry at the Fe K-edge. A dedicated high vacuum experimental chamber was set up for normal-incidence and total-reflection X-Ray Fluorescence and Absorption Spectroscopy analyses on minor amounts of mineral materials at the Stanford Synchrotron Radiation Laboratory. Results show that this experimental technique and protocol allows recognizing iron inclusion mineral fraction on insoluble dust in the 1-10 {mu}g range.

  13. Modelling the light absorption properties of particulate matter forming organic particles suspended in seawater.Part 1. Model description, classification of organic particles, and example spectra of the light absorption coefficient and the imaginary part of the refractive index of particulate matter for phytoplankton cells and phytoplankton-like particles

    Directory of Open Access Journals (Sweden)

    Bogdan Woźniak

    2005-06-01

    Full Text Available Data on organic substances in the sea are applied to distinguish hypothetical chemical classes and physical types of suspended particulate organic matter (POM in seawater. Spectra of the light absorption coefficients of particulate matter apm(λ and the imaginary refractive index n'p(λ, are assessed for some of these classes and types of POM in seawater, that is, for live phytoplankton cells and phytoplankton-like particles. The spectral characteristics of these coefficients are established and the probable ranges of variability of their absolute magnitudes defined on the basis of the mass-specific coefficients of light absorption by the various organic substances forming the particles. Also presented are mathematical relationships linking the coefficients apm(λ and n'p(λ for the various chemical classes of POM with their physical parameters, such as the relative contents of organic matter, water, air or some other gas. This article is part of a bio-optical study undertaken by the authors, the objective of which is to implement remote sensing techniques in the investigation of Baltic ecosystems (Woźniak et al. 2004.

  14. The characterization of the concentration of the single-walled carbon nanotubes in aqueous dispersion by UV-Vis-NIR absorption spectroscopy.

    Science.gov (United States)

    Yang, Bing; Ren, Lingling; Li, Luming; Tao, Xingfu; Shi, Yunhua; Zheng, Yudong

    2013-11-07

    Current and future applications of single-wall carbon nanotubes (SWCNTs) depend on the dispersion of the SWCNTs in aqueous solution and their quantitation. The concentration of SWCNTs is an important indicator to evaluate the dispersibility of the surfactant-dispersed SWCNTs suspension. Due to the complexity of the SWCNTs suspension, it is necessary to determine both the total concentration of the dispersed SWCNTs and the concentration of individually dispersed SWCNTs in aqueous suspensions, and these were evaluated through the absorbance and the resonance ratios of UV-Vis-NIR absorption spectra, respectively. However, there is no specific and reliable position assigned for either calculation of the absorbance or the resonance ratio of the UV-Vis-NIR absorption spectrum. In this paper, different ranges of wavelengths for these two parameters were studied. From this, we concluded that the wavelength range between 300 nm and 600 nm should be the most suitable for evaluation of the total concentration of dispersed SWCNTs in the suspension; also, wavelengths below 800 nm should be most suitable for evaluation of the concentration of individually dispersed SWCNTs in the suspension. Moreover, these wavelength ranges are verified by accurate dilution experiments.

  15. Characterization of Germanium Speciation in Sphalerite (ZnS from Central and Eastern Tennessee, USA, by X-ray Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Julien Bonnet

    2017-05-01

    Full Text Available X-ray absorption near edge structure (XANES spectroscopy was used on zoned sphalerites (ZnS from two world-class Mississippi Valley Type deposits, the Central and Eastern Tennessee Mining district, USA, in order to investigate germanium oxidation states. Due to the low germanium concentrations of these samples, it was necessary to perform the X-ray absorption spectroscopy (XAS in fluorescence mode. The overlapping of the Zn Kβ and Ge Kα emission lines meant that a high energy-resolution was required. This was achieved using crystal analysers and allowed a bandwidth of 1.3 eV to be obtained. Experimental spectra were compared to XANES calculations and three configurations of germanium incorporation into sphalerite were identified. The first two, the most prevalent, show germanium (II and (IV surrounded by sulphur atoms in tetrahedral coordination, suggesting the replacement of Zn by Ge. In the third configuration, germanium (IV is surrounded by oxygen atoms. This third configuration is unexpected for a zinc sulphide mineral and it resembles that of argutite (GeO2.

  16. Characterization of the electromagnetic near-field absorption in layered biological tissue in the frequency range from 30 MHz to 6000 MHz

    Energy Technology Data Exchange (ETDEWEB)

    Christ, A [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr 43, 8004 Zurich (Switzerland); Samaras, T [Radiocommunications Laboratory, Aristotle University of Thessaloniki, 541 24 Thessaloniki (Greece); Klingenboeck, A [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr 43, 8004 Zurich (Switzerland); Kuster, N [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr 43, 8004 Zurich (Switzerland)

    2006-10-07

    Currently, standards for the compliance testing of wireless devices are being extended to cover a wider frequency band and different usage patterns of mobile phones as well as of novel body-worn and handheld devices. As a consequence, not only the head but also strongly varying tissue distributions of the body are exposed to electromagnetic radiation. Several authors have reported changes in the SAR absorption of body tissue due to the presence of a low permittivity fat layer. This paper identifies two different effects which can lead to increased SAR in layered tissue in comparison to the SAR assessed using homogeneous tissue simulating liquid: (1) for larger distances between the tissue and the antenna, standing wave effects occur depending on the frequency and fat layer thickness. (2) In the very close near-field (distances approximately {lambda}/40), reactive E-field components lead to high local absorption in the skin. The latter effect occurs at lower frequencies and depends on the antenna type. Modification of the parameters of the homogeneous liquids cannot compensate for these effects. However, a conservative exposure estimate can be obtained by applying a multiplication factor between 1 and 3 to the values assessed using current experimental dosimetric techniques.

  17. Elemental characterization of herbal medicines used in Ghana by instrumental neutron activation analysis and atomic absorption spectrometry and multivariate statistical analysis

    International Nuclear Information System (INIS)

    Ayivor, J.E.; Nyarko, B.J.B.; Dampare, S.B.; Okine, L.K.

    2010-01-01

    k 0 instrumental neutron activation analysis and atomic absorption spectrometry were applied to determine multi elements in thirteen Ghanaian herbal medicines used for the management of various diseases. Concentrations of AI, Cu, Mg, Mn and Na were determined. As, Br, K, CI, and Na were determined by short and medium irradiations at a thermal neutron flux of 5x10ncm -2 s -1 . Fe, Cr, Pb, Co, Ni, Sn, Ca, Ba, Li and Sb were determined using atomic absorption spectrometry. Ba, Cu, Li and V were present at trace levels whereas AI, CI, Na, Ca were present at major levels. K, Br, Mg, Mn, Co, Ni, Fe and Sb were also present at minor levels. The precision and accuracy of the method using real samples and standard reference materials were within ±10% of the reported value. Multivariate analytical techniques, such as cluster analysis and principal component analysis (PCA)/factor analysis (FA), have been applied to evaluate the chemical variations in the herbal medicine dataset. All the 13 samples may be grouped into two statistically significant clusters, reflecting the different chemical compositions. The concentrations of elements were within the recommended daily allowances or maximum permissible levels posing no adverse effects on human health.

  18. Experimental characterization of the rectification process in ammonia-water absorption systems with a large-specific-area corrugated sheet structured packing

    Energy Technology Data Exchange (ETDEWEB)

    Sieres, Jaime; Fernandez-Seara, Jose; Uhia, Francisco J. [Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, Campus Lagoas-Marcosende No 9, 36310 Vigo, Pontevedra (Spain)

    2009-09-15

    In this paper, the mass transfer performance of a large-specific-area corrugated sheet structured packing for ammonia-water absorption refrigeration systems (AARS) is reported. An experimental facility was used to test the performance of the packing. Experimental results of the temperature, ammonia concentration and mass flow rate of the rectified vapour are presented and discussed for different operating conditions including reflux ratio values from 0.2 to 1. The volumetric vapour phase mass transfer coefficient is calculated from the measured data and compared with different correlations found in the literature. A new correlation is proposed which was fitted from the experimental data. Finally, a comparison is made between the actual packing height used in the experimental setup and the height required to obtain the same ammonia rectification in AARS with different packings previously tested by the authors. (author)

  19. Ionic Liquid Forms of Weakly Acidic Drugs in Oral Lipid Formulations: Preparation, Characterization, in Vitro Digestion, and in Vivo Absorption Studies.

    Science.gov (United States)

    Sahbaz, Yasemin; Nguyen, Tri-Hung; Ford, Leigh; McEvoy, Claire L; Williams, Hywel D; Scammells, Peter J; Porter, Christopher J H

    2017-11-06

    This study aimed to transform weakly acidic poorly water-soluble drugs (PWSD) into ionic liquids (ILs) to promote solubility in, and the utility of, lipid-based formulations. Ionic liquids (ILs) were formed directly from tolfenamic acid (Tolf), meclofenamic acid, diclofenac, and ibuprofen by pairing with lipophilic counterions. The drug-ILs were obtained as liquids or low melting solids and were significantly more soluble (either completely miscible or highly soluble) in lipid based, self-emulsifying drug delivery systems (SEDDS) when compared to the equivalent free acid. In vivo assessment of a SEDDS lipid solution formulation of Tolf didecyldimethylammonium salt and the same formulation of Tolf free acid at low dose (18 mg/kg, where the free acid was soluble in the SEDDS), resulted in similar absorption profiles and overall exposure. At high dose (100 mg/kg), solution SEDDS formulations of the Tolf ILs (didecyldimethylammonium, butyldodecyldimethylammonium or didecylmethylammonium salts) were possible, but the lower lipid solubility of Tolf free acid dictated that administration of the free acid was only possible as a suspension in the SEDDS formulation or as an aqueous suspension. Under these conditions, total drug plasma exposure was similar for the IL formulations and the free acid, but the plasma profiles were markedly different, resulting in flatter, more prolonged exposure profiles and reduced C max for the IL formulations. Isolation of a weakly acidic drug as an IL may therefore provide advantage as it allows formulation as a solution SEDDS rather than a lipid suspension, and in some cases may provide a means of slowing or sustaining absorption. The current studies compliment previous studies with weakly basic PWSD and demonstrate that transformation into highly lipophilic ILs is also possible for weakly acidic compounds.

  20. Characterizing the Solvated Structure of Photoexcited [Os(terpy)2]2+ with X-ray Transient Absorption Spectroscopy and DFT Calculations

    DEFF Research Database (Denmark)

    Zhang, Xiaoyi; Pápai, Mátyás Imre; Møller, Klaus Braagaard

    2016-01-01

    Characterizing the geometric and electronic structures of individual photoexcited dye molecules in solution is an important step towards understanding the interfacial properties of photo-active electrodes. The broad family of "red sensitizers" based on osmium(II) polypyridyl compounds often......,2':6',2″-terpyridine) solvated in methanol. From the EXAFS analysis, the structural changes can be characterized by a slight overall expansion of the first coordination shell [OsN6]. DFT calculations supports the XTA results. They also provide additional information about the nature of the molecular orbitals...

  1. Characterization of local chemistry and disorder in synthetic and natural α-Al2O3 materials by X-ray absorption near edge structure spectroscopy

    International Nuclear Information System (INIS)

    Mottana, A.; Murata, T.

    1997-11-01

    X-ray absorption fine spectra at the Al K-edge were measured experimentally on and calculated theoretically via the multiple-scattering formalism for a chemically pure and physically perfect synthetic α-Al 2 O 3 (α-alumina), a natural 'ruby/sapphire' (corundum) and a series of artificial 'corundum' produced for technical purposes and used as geochemical standards. The Al K-edge spectra differ despite of the identical coordination (short-range arrangement) assumed by O around Al, and vary slightly in relation to the slightly different chemistries of the materials (substitutional defects) as well as on account of the location taken by foreign atoms in the structural lattices (positional defects). A quantitative treatment of the observed changes is made in terms of short-range modification of the coordination polyhedron and of medium- to long-range modifications in the overall structure; both of them induced by substitutions. In some technical 'corundums', the impurities of admixed 'β-alumina', where Al is both in four- and six-fold coordination, produce another small but detectable effect on Al K-edges. Therefore, XAFS spectroscopy proves its potentials for both measuring a light element such as Al, and detecting minor coordination changes and substitutions (ca. 1∼3 wt.% as oxide) of the absorber by dilute other atoms, at least under favorable conditions as those occurring in this system are

  2. Characterization of the core-shell interaction of differently stabilized transition-metal nanoparticles by means of X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Bucher, S.

    2002-05-01

    Transition metal nanoparticles with different surfactants were investigated using X-ray absorption spectroscopy (XAS) to obtain information about the interaction between metal core and protecting shell. For tetraalkylammoniumchloride stabilized Pd- and Co-colloids, a detailed model of the interaction between the metal core and the stabilizing shell could be established, in which chlorine is the connecting element between the metal core and the organic protection cover. Different lengths of the alkyl-chains can cause different equilibrium positions for the chlorine atoms. At aluminum-organic stabilized Pt-colloids, Al K-XANES and Pt L III -XAS were carried out. In this case, it turned out that aluminum is the connecting element between metal core and protection shell. After modification of the shell by connecting different molecules to the outside of the shell, rearrangements of the shell could be observed. In contrast to the surfactant stabilized systems discussed above, metallic covers, especially gold coatings, of Co-particles did not lead to a complete protection shell. In all cases, the cobalt in the nanoparticles was oxidized. A core shell structure could not be verified for any of the metallic stabilized colloids. (orig.)

  3. Absorption of metals and characterization of chemical elements present in three species of Gracilaria (Gracilariaceae Greville: a genus of economical importance

    Directory of Open Access Journals (Sweden)

    Angela P. Tonon

    2011-04-01

    Full Text Available Gracilaria Greville is a genus of seaweed that is economically explored by the cosmetic, pharmaceutical and food industries. One of the biggest problems associated with growing Gracilaria is the discharge of heavy metals into the marine environment. The absorption of heavy metals was investigated with the macroalga Gracilaria tenuistipitata Zhang et Xia, cultivated in a medium containing copper (Cu and cadmium (Cd. In biological samples, EC50 concentrations of 1 ppm for cadmium and 0.95 ppm for copper were used. These concentrations were based on seaweed growth curves obtained over a period of six days in previous studies. ICP-AES was used to determine the amount of metal that seaweeds absorbed during this period. G. tenuistipitata was able to bioaccumulate both metals, about 17% of copper and 9% of cadmium. Basal natural levels of Cu were found in control seaweeds and in G. tenuistipitata exposed to Cd. In addition, the repertoire of other important chemical elements, as well as their concentrations, was determined for G. tenuistipitata and two other important seaweeds, G. birdiae Plastino & Oliveira and G. domingensis (Kützing Sonder ex Dickie, collected in natural environments on the Brazilian shore.

  4. In Situ Industrial Bimetallic Catalyst Characterization using Scanning Transmission Electron Microscopy and X-ray Absorption Spectroscopy at One Atmosphere and Elevated Temperature.

    Science.gov (United States)

    Prestat, Eric; Kulzick, Matthew A; Dietrich, Paul J; Smith, Mr Matthew; Tien, Mr Eu-Pin; Burke, M Grace; Haigh, Sarah J; Zaluzec, Nestor J

    2017-08-18

    We have developed a new experimental platform for in situ scanning transmission electron microscope (STEM) energy dispersive X-ray spectroscopy (EDS) which allows real time, nanoscale, elemental and structural changes to be studied at elevated temperature (up to 1000 °C) and pressure (up to 1 atm). Here we demonstrate the first application of this approach to understand complex structural changes occurring during reduction of a bimetallic catalyst, PdCu supported on TiO 2 , synthesized by wet impregnation. We reveal a heterogeneous evolution of nanoparticle size, distribution, and composition with large differences in reduction behavior for the two metals. We show that the data obtained is complementary to in situ STEM electron energy loss spectroscopy (EELS) and when combined with in situ X-ray absorption spectroscopy (XAS) allows correlation of bulk chemical state with nanoscale changes in elemental distribution during reduction, facilitating new understanding of the catalytic behavior for this important class of materials. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Characterization of thin poly(dimethylsiloxane)-based tissue-simulating phantoms with tunable reduced scattering and absorption coefficients at visible and near-infrared wavelengths.

    Science.gov (United States)

    Greening, Gage J; Istfan, Raeef; Higgins, Laura M; Balachandran, Kartik; Roblyer, Darren; Pierce, Mark C; Muldoon, Timothy J

    2014-01-01

    Optical phantoms are used in the development of various imaging systems. For certain applications, the development of thin phantoms that simulate the physical size and optical properties of tissue is important. Here, we demonstrate a method for producing thin phantom layers with tunable optical properties using poly(dimethylsiloxane) (PDMS) as a substrate material. The thickness of each layer (between 115 and 880 μm) was controlled using a spin coater. The reduced scattering and absorption coefficients were controlled using titanium dioxide and alcohol-soluble nigrosin, respectively. These optical coefficients were quantified at six discrete wavelengths (591, 631, 659, 691, 731, and 851 nm) at varying concentrations of titanium dioxide and nigrosin using spatial frequency domain imaging. From the presented data, we provide lookup tables to determine the appropriate concentrations of scattering and absorbing agents to be used in the design of PDMS-based phantoms with specific optical coefficients. In addition, heterogeneous phantoms mimicking the layered features of certain tissue types may be fabricated from multiple stacked layers, each with custom optical properties. These thin, tunable PDMS optical phantoms can simulate many tissue types and have broad imaging calibration applications in endoscopy, diffuse optical spectroscopic imaging, and optical coherence tomography, etc.

  6. X-ray absorption spectroscopic and magnetic characterization of cobalt-doped zinc oxide nanocrystals prepared by the molten-salt method

    International Nuclear Information System (INIS)

    Han, Ah Reum; Hwang, Seong-Ju; Zhao, Yongnan; Kwon, Young-Uk

    2008-01-01

    The local atomic arrangement and electronic structure of the Co-doped Zn 1-x Co x O nanocrystal have been quantitatively examined along with its magnetic properties. According to our analysis using powder X-ray diffraction, electron microscopy, and Zn K-edge X-ray absorption spectroscopy (XAS), phase-pure wurzite-structured Zn 1-x Co x O nanocrystals have been successfully synthesized via the molten-salt method. The Co K-edge XAS analysis clearly demonstrates that all the Co 2+ ions are substituted for the tetrahedral Zn sites of the Wurzite structure with a coordination number of 3.9 and a bond distance of 1.97 A, ruling out the presence of magnetic impurity phase and Co-metal cluster. Magnetization measurements reveal that the present Zn 1-x Co x O sample does not show any ferromagnetic transition down to 2 K. In this regard, we can conclude that Co-doped zinc oxide is not ferromagnetic but the previously reported ferromagnetism in this phase would be an extrinsic property

  7. Oral Exposure and Absorption of Toxicants

    Science.gov (United States)

    This chapter provides an overview of the toxicokinetics of orally absorbed xenobiotics. This includes a description of the basic anatomy and physiology of the digestive tract most relevant to the absorption process. In addition, differences in anatomy and physiology between human...

  8. Nutrition and magnesium absorption

    OpenAIRE

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true magnesium absorption was neither affected by soybean protein in the diet nor by supplemental phytate. The inhibitory influence of soybean protein and phytate on apparent magnesium absorption was found ...

  9. An outdoor investigation of the absorption degradation of single ...

    Indian Academy of Sciences (India)

    Fourier transform infrared spectroscopy (FTIR) was used for the absorption characterization. The rationale behind the outdoor deployment was to deduce a practical effect of hot spot formation on the module's absorption ability.The results show a direct correlation between localized heat and the absorption degradation.

  10. Absorption and excretion tests

    International Nuclear Information System (INIS)

    Berberich, R.

    1988-01-01

    The absorption and excretion of radiopharmaceuticals is still of interest in diagnostic investigations of nuclear medicine. In this paper the most common methods of measuring absorption and excretion are described. The performance of the different tests and their standard values are discussed. More over the basic possibilities of measuring absorption and excretion including the needed measurement equipments are presented. (orig.) [de

  11. The Core/Shell Structure of CdSe/ZnS Quantum Dots Characterized by X-Ray Absorption Fine Spectroscopy

    Directory of Open Access Journals (Sweden)

    Huijing Wei

    2015-01-01

    Full Text Available Understanding the chemical and physical properties of core/shell nanocrystal quantum dots (QDs is key for their use in light-emission applications. In this paper, a single-step injection-free scalable synthetic method is applied to prepare high-quality core/shell QDs with emission wavelengths of 544 nm, 601 nm, and 634 nm. X-ray absorption fine structure spectra are used to determine the core/shell structure of CdSe/ZnS quantum dots. Moreover, theoretical XANES spectra calculated by FEFF.8.20 are used to determine the structure of Se and S compounds. The QD samples displayed nearly spherical shapes with diameters of approximately 3.4 ± 0.5 nm (634 nm, 4.5 ± 0.4 nm (601 nm, and 5.5 ± 0.5 nm (544 nm. With XANES results and MS calculations, it is indicated that sphalerite ZnS capped with organic sulfur ligands should be the shell structure. Wurtzite CdSe is the main core structure with a Cd-Se bond length of 2.3 Å without phase shift. This means that different emission wavelengths are only due to the crystal size with single-step injection-free synthesis. Therefore, single-step injection-free synthesis could generate a nearly ideal core/shell structure of CdSe/ZnS QDs capped with an organic sulfur ligand.

  12. Calcium absorption and achlorhydria

    International Nuclear Information System (INIS)

    Recker, R.R.

    1985-01-01

    Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium used as the carrier. Mean calcium absorption (+/- S.D.) in the patients with achlorhydria was 0.452 +/- 0.125 for citrate and 0.042 +/- 0.021 for carbonate (P less than 0.0001). Fractional calcium absorption in the normal subjects was 0.243 +/- 0.049 for citrate and 0.225 +/- 0.108 for carbonate (not significant). Absorption of calcium from carbonate in patients with achlorhydria was significantly lower than in the normal subjects and was lower than absorption from citrate in either group; absorption from citrate in those with achlorhydria was significantly higher than in the normal subjects, as well as higher than absorption from carbonate in either group. Administration of calcium carbonate as part of a normal breakfast resulted in completely normal absorption in the achlorhydric subjects. These results indicate that calcium absorption from carbonate is impaired in achlorhydria under fasting conditions. Since achlorhydria is common in older persons, calcium carbonate may not be the ideal dietary supplement

  13. Local structure near actinides and nucleating elements in borosilicate glass for nuclear industry: Results of X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Petit-Maire, D.

    1988-01-01

    Possibilities and limits of X-ray absorption spectroscopy for cation site description in silicate glasses and possible applications for complex glasses, like glass for fission product containment, are examined. In borosilicate glasses two types of sites are evidenced for actinides at the valence 4: Coordinance 6 sites with a narrow radial distribution for the distance An-0; higher coordination (7, 8 or more) with a wider and asymmetrical radial distribution. Proportion of low coordinance sites increases when cation size decreases (Th > Np). U and Np VI and V are characterized as actinyles with a chain 0-An-0 practically linear, coordinance in a plane perpendicular to this complex is probably 5. X-ray absorption spectroscopy allows an accurate description of actinide sites in fission product glasses [fr

  14. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  15. Re-description of Xysticus bimaculatus L. Koch, 1867 (Araneae, Thomisidae and characterization of its subsocial lifestyle

    Directory of Open Access Journals (Sweden)

    Jasmin Ruch

    2014-07-01

    Full Text Available Spiders have become an important model to study the evolution of sociality, but a lack of their detailed natural history and taxonomy hinders broader comparative studies. Group-living crab spiders (Thomisidae provide an excellent contrast to other social spiders since they lack a communal capture web, which was thought to be a critical factor in the evolution of sociality. Only three non-webbuilding crab-spider species are known to be subsocial or social, all of which belong to the genus Diaea Thorell, 1869. The aim of this study is to describe the social lifestyle of Xysticus bimaculatus L. Koch, 1867 for the first time. Furthermore, we present a detailed re-description of this species and discuss its taxonomic implications. Like other subsocial crab spiders, X. bimaculatus builds nests from tree leaves. Nests contain up to 38 spiders and sometimes several adult females, indicating the species may be at a transitory stage between subsociality and permanent sociality.

  16. Solar absorption surface panel

    Science.gov (United States)

    Santala, Teuvo J.

    1978-01-01

    A composite metal of aluminum and nickel is used to form an economical solar absorption surface for a collector plate wherein an intermetallic compound of the aluminum and nickel provides a surface morphology with high absorptance and relatively low infrared emittance along with good durability.

  17. Nutrition and magnesium absorption

    NARCIS (Netherlands)

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true

  18. Zeeman atomic absorption spectroscopy

    International Nuclear Information System (INIS)

    Loos-Vollebregt, M.T.C. de.

    1980-01-01

    A new method of background correction in atomic absorption spectroscopy has recently been introduced, based on the Zeeman splitting of spectral lines in a magnetic field. A theoretical analysis of the background correction capability observed in such instruments is presented. A Zeeman atomic absorption spectrometer utilizing a 50 Hz sine wave modulated magnetic field is described. (Auth.)

  19. Phenotypic characterization of skeletal abnormalities of osteopotentia mutant mice by micro-CT: a descriptive approach with emphasis on reconstruction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Roemer, Frank W. [Department of Radiology, Klinikum Augsburg, Augsburg (Germany); Boston University School of Medicine, Quantitative Imaging Center, Boston, MA (United States); University of California, San Francisco, Osteoporosis and Arthritis Research Group, San Francisco, CA (United States); Boston University Medical Center, Department of Radiology, Boston, MA (United States); Mohr, Andreas [University of California, San Francisco, Osteoporosis and Arthritis Research Group, San Francisco, CA (United States); Sligo General Hospital, Department of Radiology, Sligo (Ireland); Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center, Boston, MA (United States); University of California, San Francisco, Osteoporosis and Arthritis Research Group, San Francisco, CA (United States); Jiang, Yebin [University of California, San Francisco, Osteoporosis and Arthritis Research Group, San Francisco, CA (United States); University of Michigan Medical School, Osteoporosis and Arthritis Laboratory, Musculoskeletal Division, Department of Radiology, Ann Arbor, MI (United States); Schlechtweg, Philipp [University of Erlangen, Department of Radiology, Erlangen (Germany); Genant, Harry K. [University of California, San Francisco, Osteoporosis and Arthritis Research Group, San Francisco, CA (United States); CCBR-SYNARC, Inc., San Francisco, CA (United States); Sohaskey, Michael L. [University of California, Berkeley, Department of Molecular and Cell Biology and Center for Integrative Genomics, Berkeley, CA (United States)

    2011-08-15

    The novel protein osteopotentia (Opt) has recently been described as an essential regulator of postnatal osteoblast maturation and might possibly be responsible for some of the rarer types of osteogenesis imperfecta. Our aim was the evaluation of micro CT for the qualitative morphological assessment of skeletal abnormalities of Osteopotentia-mutant mice in comparison to radiography and histology. Four homozygous mice with insertional mutations in the Opt gene and three wild-type controls were examined ex vivo using radiography and micro-CT. Two of the homozygous animals were evaluated histologically (trichrome reagent). For the micro-CT evaluation three-dimensional (3D) surface reconstructions and two-dimensional (2D) multiplanar reformations (MPRs) were applied. The Opt-homozygous mice exhibited severe growth. The radiographic examinations showed osteopenia and fractures with hypertrophic callus formation and pseudarthroses of the forelimbs and ribs. Micro-CT confirmed these findings and was able to demonstrate additional fractures especially at smaller bones such as the metacarpals and phalanges. Additional characterization and superior delineation of cortices and fracture fragments was achieved by 2D MPRs. Histological correlation verified several of these imaging findings. Micro-CT is able to screen Opt-mutant mice for osseous pathologies and furthermore characterize these anomalies. The modality seems superior to conventional radiography, but is not able to demonstrate cellular pathology. However, histology is destructive and more time- and material-consuming than micro-CT. Additional information may be gathered by 2D MPRs. (orig.)

  20. Ultrasonic absorption in polymethylmethacrylate at low temperatures

    International Nuclear Information System (INIS)

    Federle, G.; Hunklinger, S.

    1982-01-01

    This chapter reports on a study of the absorption of longitudinal sound waves at frequencies between 15 and 195 MHz and temperatures between 0.4K and 300K using commercial PMMA. It demonstrates that the acoustic absorption of PMMA does not steadily decrease on cooling. Below 1K the absorption varies linearly with temperature and can be explained after a small modification of the so-called ''tunnelling model'' which is well-known in the description of inorganic glasses. This is an unexpected maximum at 12K which has a frequency independent position. This behavior is explained by assuming a high density of tunnelling states with well-defined asymmetries and tunnel splittings. It is pointed out that these states couple weakly to the amorphous network and are most probably due to rotational tunnelling of the ester methyl group

  1. Uranium absorption study pile

    International Nuclear Information System (INIS)

    Raievski, V.; Sautiez, B.

    1959-01-01

    The report describes a pile designed to measure the absorption of fuel slugs. The pile is of graphite and comprises a central section composed of uranium rods in a regular lattice. RaBe sources and BF 3 counters are situated on either side of the center. A given uranium charge is compared with a specimen charge of about 560 kg, and the difference in absorption between the two noted. The sensitivity of the equipment will detect absorption variations of about a few ppm boron (10 -6 boron per gr. of uranium) or better. (author) [fr

  2. YUCCA MOUNTAIN SITE DESCRIPTION

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  3. YUCCA MOUNTAIN SITE DESCRIPTION

    International Nuclear Information System (INIS)

    Simmons, A.M.

    2004-01-01

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel

  4. Revisiting Absorptive Capacity

    DEFF Research Database (Denmark)

    de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher

    learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning......Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...

  5. Absorption fluids data survey

    Science.gov (United States)

    Macriss, R. A.; Zawacki, T. S.

    Development of improved data for the thermodynamic, transport and physical properties of absorption fluids were studied. A specific objective of this phase of the study is to compile, catalog and coarse screen the available US data of known absorption fluid systems and publish it as a first edition document to be distributed to manufacturers, researchers and others active in absorption heat pump activities. The methodology and findings of the compilation, cataloguing and coarse screening of the available US data on absorption fluid properties and presents current status and future work on this project are summarized. Both in house file and literature searches were undertaken to obtain available US publications with pertinent physical, thermodynamic and transport properties data for absorption fluids. Cross checks of literature searches were also made, using available published bibliographies and literature review articles, to eliminate secondary sources for the data and include only original sources and manuscripts. The properties of these fluids relate to the liquid and/or vapor state, as encountered in normal operation of absorption equipment employing such fluids, and to the crystallization boundary of the liquid phase, where applicable. The actual data were systematically classified according to the type of fluid and property, as well as temperature, pressure and concentration ranges over which data were available. Data were sought for 14 different properties: Vapor-Liquid Equilibria, Crystallization Temperature, Corrosion Characteristics, Heat of Mixing, Liquid-Phase-Densities, Vapor-Liquid-Phase Enthalpies, Specific Heat, Stability, Viscosity, Mass Transfer Rate, Heat Transfer Rate, Thermal Conductivity, Flammability, and Toxicity.

  6. Transfer path based tyre absorption tests

    NARCIS (Netherlands)

    Tijs, E.; Makwana, B.K.; Peksel, O.; Amarnath, S.K.P.; Bekke, Dirk; Krishnan, K.S.

    2013-01-01

    The development process of a tyre usually involves a combination of simulation and testing techniques focused on characterizing acoustic/aerodynamic and vibrational phenomena. One of the acoustic phenomenon of interest is the absorption of the tyre, which affects the sound radiated. This properties

  7. Absorption cooling device. Absorptions-Kuehlvorrichtung

    Energy Technology Data Exchange (ETDEWEB)

    Bourne, J.; Vardi, I.; Kimchi, Y.; Ben-Dror, J.

    1980-03-25

    The invention concerns improvements of absorption refrigerators, where a lithium chloride or lithium bromide/water cycle is used. According to the invention an inner separating or dividing structure between different functional parts of a machine of this type is provided. The structure contains two sections of wall, which are separated from one another by a suitable space, in order to achieve thermal insulation. This air space is provided with an opening in the direction towards the inside of the container and the opening is shielded to prevent the entry of liquids (in liquid or spray form).

  8. Implementing a Description Grammar Interpreter : A Notation for Descriptions and Description Rules

    NARCIS (Netherlands)

    Stouffs, R.M.F.

    2015-01-01

    Description grammars represent a formalism for generating verbal descriptions of designs, used in conjunction with shape grammars. A description grammar constitutes a set of description rules that define a language of descriptions. A description grammar interpreter implements the mechanisms to

  9. Spectrophotometer-Integrating-Sphere System for Computing Solar Absorptance

    Science.gov (United States)

    Witte, William G., Jr.; Slemp, Wayne S.; Perry, John E., Jr.

    1991-01-01

    A commercially available ultraviolet, visible, near-infrared spectrophotometer was modified to utilize an 8-inch-diameter modified Edwards-type integrated sphere. Software was written so that the reflectance spectra could be used to obtain solar absorptance values of 1-inch-diameter specimens. A descriptions of the system, spectral reflectance, and software for calculation of solar absorptance from reflectance data are presented.

  10. Vitamin A absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Investigation of the absorption of vitamin A and related substances is complicated by the multiplicity of forms in which they occur in the diet and by the possibility that they may be subject to different mechanisms of absorption. Present knowledge of these mechanisms is inadequate, especially in the case of carotenoids. Numerous tests of absorption have been developed. The most common has been the biochemical measurement of the rise in plasma vitamin A after an oral dose of retinol or retinyl ester, but standardization is inadequate. Radioisotope tests based upon assay of serum or faecal activity following oral administration of tritiated vitamin A derivaties hold considerable promise, but again standardization is inadequate. From investigations hitherto performed it is known that absorption of vitamin A is influenced by several diseases, although as yet the consistency of results and the correlation with other tests of intestinal function have often been poor. However, the test of vitamin A absorption is nevertheless of clinical importance as a specialized measure of intestinal function. (author)

  11. Gastrointestinal absorption of plutonium

    International Nuclear Information System (INIS)

    Larsen, R.P.; Oldham, R.D.; Bhattacharyya, M.H.; Moretti, E.S.; Austin, D.J.

    1981-01-01

    An investigation has been made of the effect of the oxidation state of plutonium on its absorption from the gastrointestinal tract. For mice and rats that have been starved prior to gastrointestinal administration, there is no significant difference between the absorption factors for Pu(IV) and Pu(VI). The value obtained for Pu(VI) is an order of magnitude lower than that reported previously. The value obtained for Pu(IV) is two orders of magnitude higher than those reported previously for nitrate solutions and the same as those reported for citrate solutions

  12. Quantum Absorption Refrigerator

    Science.gov (United States)

    Levy, Amikam; Kosloff, Ronnie

    2012-02-01

    A quantum absorption refrigerator driven by noise is studied with the purpose of determining the limitations of cooling to absolute zero. The model consists of a working medium coupled simultaneously to hot, cold, and noise baths. Explicit expressions for the cooling power are obtained for Gaussian and Poisson white noise. The quantum model is consistent with the first and second laws of thermodynamics. The third law is quantified; the cooling power Jc vanishes as Jc∝Tcα, when Tc→0, where α=d+1 for dissipation by emission and absorption of quanta described by a linear coupling to a thermal bosonic field, where d is the dimension of the bath.

  13. Aerosol optical absorption measurements with photoacoustic spectroscopy

    Science.gov (United States)

    Liu, Kun; Wang, Lei; Liu, Qiang; Wang, Guishi; Tan, Tu; Zhang, Weijun; Chen, Weidong; Gao, Xiaoming

    2015-04-01

    Many parameters related to radiative forcing in climate research are known only with large uncertainties. And one of the largest uncertainties in global radiative forcing is the contribution from aerosols. Aerosols can scatter or absorb the electromagnetic radiation, thus may have negative or positive effects on the radiative forcing of the atmosphere, respectively [1]. And the magnitude of the effect is directly related to the quantity of light absorbed by aerosols [2,3]. Thus, sensitivity and precision measurement of aerosol optical absorption is crucial for climate research. Photoacoustic spectroscopy (PAS) is commonly recognized as one of the best candidates to measure the light absorption of aerosols [4]. A PAS based sensor for aerosol optical absorption measurement was developed. A 532 nm semiconductor laser with an effective power of 160 mW was used as a light source of the PAS sensor. The PAS sensor was calibrated by using known concentration NO2. The minimum detectable optical absorption coefficient (OAC) of aerosol was determined to be 1 Mm-1. 24 hours continues measurement of OAC of aerosol in the ambient air was carried out. And a novel three wavelength PAS aerosol OAC sensor is in development for analysis of aerosol wavelength-dependent absorption Angstrom coefficient. Reference [1] U. Lohmann and J. Feichter, Global indirect aerosol effects: a review, Atmos. Chem. Phys. 5, 715-737 (2005) [2] M. Z. Jacobson, Strong radiative heating due to the mixing state of black carbon in atmospheric aerosols, Nature 409, 695-697 (2001) [3] V. Ramanathan and G. Carmichae, Global and regional climate changes due to black carbon, nature geoscience 1, 221-227 (2008) [4] W.P Arnott, H. Moosmuller, C. F. Rogers, T. Jin, and R. Bruch, Photoacoustic spectrometer for measuring light absorption by aerosol: instrument description. Atmos. Environ. 33, 2845-2852 (1999).

  14. Chemical Absorption Materials

    DEFF Research Database (Denmark)

    Thomsen, Kaj

    2011-01-01

    Chemical absorption materials that potentially can be used for post combustion carbon dioxide capture are discussed. They fall into five groups, alkanolamines, alkali carbonates, ammonia, amino acid salts, and ionic liquids. The chemistry of the materials is discussed and advantages and drawbacks...

  15. Neutron resonance absorption theory

    International Nuclear Information System (INIS)

    Reuss, P.

    1991-11-01

    After some recalls on the physics of neutron resonance absorption during their slowing down, this paper presents the main features of the theoretical developments performed by the french school of reactor physics: the effective reaction rate method so called Livolant-Jeanpierre theory, the generalizations carried out by the author, and the probability table method [fr

  16. Analysis of photoisomerizable dyes using laser absorption and fluorescence techniques

    International Nuclear Information System (INIS)

    Duchowicz, R.; Di Paolo, R.E.; Scaffardi, L.; Tocho, J.O.

    1992-01-01

    The attention of the present report has been directed mainly to the description of laser-based techniques developed in order to obtain kinetic and spectroscopic properties of polymethine cyanine dyes in solution. Special attention was dedicated to photoisomerizable molecules where the absorption spectra of both isomers are strongly overlapped. As an example, measurements of two different dyes of laser technological interest, DTCI and DODCI were performed. The developed methods provide a complete quantitative description of photophysical processes. (author). 14 refs, 6 figs

  17. Neutron scattering and absorption properties

    Energy Technology Data Exchange (ETDEWEB)

    Holden, N.E.

    1993-12-01

    The Table in this report presents an evaluated set of values for the experimental quantities, which characterize the properties for scattering and absorption of neutrons. The neutron cross section is given for room temperature neutrons, 20.43{degree}C, corresponds to a thermal neutron energy of 0.0253 electron volts (eV) or a neutron velocity of 2200 meters/second. The neutron resonance integral is defined over the energy range from 0.5 eV to 0.1 {times} 10{sup 6} eV, or 0.1 MeV. A list of the major references used is given below. The literature cutoff data is October 1993. Uncertainties are given in parentheses. Parentheses with two or more numbers indicate values to the excited states(s) and to the ground state of the product nucleus.

  18. Description and Flow Characterization of Hypersonic Facilities

    Science.gov (United States)

    1994-08-01

    Computing Flows in Chemical Nonequilibrium." AIAA Paper 89-0199, Presented at the 27th Aerospace Science Meeting, Reno, Nevada , January 9-12, 1989...percentage of atomic oxygen, atmoic nitrogen, free electrons, and oxides of nitrogen (NOx). These species are likely to be in either thermal or chemical

  19. Risk Characterization uncertainties associated description, sensitivity analysis

    International Nuclear Information System (INIS)

    Carrillo, M.; Tovar, M.; Alvarez, J.; Arraez, M.; Hordziejewicz, I.; Loreto, I.

    2013-01-01

    The power point presentation is about risks to the estimated levels of exposure, uncertainty and variability in the analysis, sensitivity analysis, risks from exposure to multiple substances, formulation of guidelines for carcinogenic and genotoxic compounds and risk subpopulations

  20. Absorptive Capacity and Diversity

    DEFF Research Database (Denmark)

    Kristinsson, Kári

    international business, organizational economics, strategic management, technology management and last but not least neo-Schumpeterian economics. The goal of this dissertation is to examine what many consider as neglected arguments from the work by Cohen and Levinthal and thereby illuminate an otherwise......One of the most influential contributions to neo-Schumpeterian economics is Cohen and Levinthal‘s papers on absorptive capacity. Since their publication in the late 1980s and early 1990s the concept absorptive capacity has had substantial impact on research in economics and management, including...... overlooked area of research. Although research based on Cohen and Levinthal‘s work has made considerable impact, there is scarcity of research on certain fundamental points argued by Cohen and Levinthal. Among these is the importance of employee diversity as well as the type and nature of interaction between...

  1. Análise descritiva por ordenação: aplicação na caracterização sensorial de biscoitos laminados salgados Ranking descriptive analysis: application in the sensory characterization of cracker biscuits

    Directory of Open Access Journals (Sweden)

    Lorena Carnelocce

    2012-12-01

    Full Text Available A Análise Descritiva por Ordenação (ADO foi aplicada na caracterização de biscoitos cream cracker e água e sal comerciais, empregando julgadores pré-selecionados, mas sem experiência prévia em análise sensorial. O método compreendeu as etapas de levantamento e conceituação dos atributos, treinamento qualitativo e análise final, utilizando o procedimento de ordenação. Para verificação da eficiência na discriminação das amostras, o procedimento de ordenação foi comparado ao uso de escala não estruturada. Dados de caracterização instrumental de textura e cor foram comparados aos obtidos na descrição sensorial dos biscoitos. Análise Procrustes Generalizada foi utilizada na avaliação dos dados de ordenação ou escala, e os resultados da ordenação foram também avaliados por Teste de Friedman. A eficiência da equipe e a configuração das amostras foram similares no procedimento de ordenação e com o uso de escala. Após um treinamento qualitativo e uma avaliação inicial das amostras por um procedimento de ordenação, os julgadores não apresentaram divergência de comportamento, mesmo empregando um procedimento mais difícil (uso de escala. Cor e aroma de assado e sabor tostado, aroma de manteiga e sabor amanteigado, crocância (manual e na boca e uniformidade da cor foram os atributos mais importantes na discriminação. A ADO permitiu a caracterização e a discriminação de modo concordante com a composição indicada no rótulo dos produtos e os resultados instrumentais de textura e cor.Ranking Descriptive Analysis (RDA was applied to the characterization of commercial cream cracker and water and salt biscuits, using pre-selected assessors with no previous experience in sensory analysis. The method had the following steps: development of attributes, glossary and references, qualitative training and final analysis using the ranking procedure. To check the efficiency in discriminating the samples, the ranking

  2. Sound absorption of snow

    OpenAIRE

    Maysenhölder, W.; Schneebeli, M.; Zhou, X.; Zhang, T.; Heggli, M.

    2008-01-01

    Recently fallen snow possesses good sound-absorbing properties. This fact is well-known and confirmed by measurements. Is the filigree structure of snowflakes decisive? In principle we know that the sound-absorbing capacity of a porous material is dependent on its structure. But until now the question as to which structural characteristics are significant has been insufficiently answered. Detailed investigations of snow are to explain this fact by precise measurements of the sound absorption,...

  3. Iron absorption studies

    International Nuclear Information System (INIS)

    Ekenved, G.

    1976-01-01

    The main objective of the present work was to study iron absorption from different iron preparations in different types of subjects and under varying therapeutic conditions. The studies were performed with different radioiron isotope techniques and with a serum iron technique. The preparations used were solutions of ferrous sulphate and rapidly-disintegrating tablets containing ferrous sulphate, ferrous fumarate and ferrous carbonate and a slow-release ferrous sulphate tablet of an insoluble matrix type (Duroferon Durules). The serum iron method was evaluated and good correlation was found between the serum iron response and the total amount of iron absorbed after an oral dose of iron given in solution or in tablet form. New technique for studying the in-vivo release properties of tablets was presented. Iron tablets labelled with a radio-isotope were given to healthy subjects. The decline of the radioactivity in the tablets was followed by a profile scanning technique applied to different types of iron tablets. The release of iron from the two types of tablets was shown to be slower in vivo than in vitro. It was found that co-administration of antacids and iron tablets led to a marked reduction in the iron absorption and that these drugs should not be administered sumultaneously. A standardized meal markedly decreased the absorbability of iron from iron tablets. The influence of the meal was more marked with rapidly-disintegrating than with slow-release ferrous sulphate tablets. The absorption from rapidly-disintegrating and slow-release ferrous sulphate tablets was compared under practical clinical conditions during an extended treatment period. The studies were performed in healthy subjects, blood donors and patients with iron deficiency anaemia and it was found that the absorption of iron from the slow-release tablets was significantly better than from the rapidly-disintegrating tablets in all three groups of subjects. (author)

  4. Total Absorption Spectroscopy

    International Nuclear Information System (INIS)

    Rubio, B.; Gelletly, W.

    2007-01-01

    The problem of determining the distribution of beta decay strength (B(GT)) as a function of excitation energy in the daughter nucleus is discussed. Total Absorption Spectroscopy is shown to provide a way of determining the B(GT) precisely. A brief history of such measurements and a discussion of the advantages and disadvantages of this technique, is followed by examples of two recent studies using the technique. (authors)

  5. Relic Neutrino Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, b

    2004-01-28

    Resonant annihilation of extremely high-energy cosmic neutrinos on big-bang relic anti-neutrinos (and vice versa) into Z-bosons leads to sizable absorption dips in the neutrino flux to be observed at Earth. The high-energy edges of these dips are fixed, via the resonance energies, by the neutrino masses alone. Their depths are determined by the cosmic neutrino background density, by the cosmological parameters determining the expansion rate of the universe, and by the large redshift history of the cosmic neutrino sources. We investigate the possibility of determining the existence of the cosmic neutrino background within the next decade from a measurement of these absorption dips in the neutrino flux. As a by-product, we study the prospects to infer the absolute neutrino mass scale. We find that, with the presently planned neutrino detectors (ANITA, Auger, EUSO, OWL, RICE, and SalSA) operating in the relevant energy regime above 10{sup 21} eV, relic neutrino absorption spectroscopy becomes a realistic possibility. It requires, however, the existence of extremely powerful neutrino sources, which should be opaque to nucleons and high-energy photons to evade present constraints. Furthermore, the neutrino mass spectrum must be quasi-degenerate to optimize the dip, which implies m{sub {nu}} 0.1 eV for the lightest neutrino. With a second generation of neutrino detectors, these demanding requirements can be relaxed considerably.

  6. X-ray absorption spectroscopy: EXAFS [Extended X-ray Absorption Fine Structure] and XANES [X-ray Absorption Near Edge Structure

    International Nuclear Information System (INIS)

    Alp, E.E.; Mini, S.M.; Ramanathan, M.

    1990-04-01

    The x-ray absorption spectroscopy (XAS) had been an essential tool to gather spectroscopic information about atomic energy level structure in the early decades of this century. It has also played an important role in the discovery and systematization of rare-earth elements. The discovery of synchrotron radiation in 1952, and later the availability of broadly tunable synchrotron based x-ray sources have revitalized this technique since the 1970's. The correct interpretation of the oscillatory structure in the x-ray absorption cross-section above the absorption edge by Sayers et. al. has transformed XAS from a spectroscopic tool to a structural technique. EXAFS (Extended X-ray Absorption Fine Structure) yields information about the interatomic distances, near neighbor coordination numbers, and lattice dynamics. An excellent description of the principles and data analysis techniques of EXAFS is given by Teo. XANES (X-ray Absorption Near Edge Structure), on the other hand, gives information about the valence state, energy bandwidth and bond angles. Today, there are about 50 experimental stations in various synchrotrons around the world dedicated to collecting x-ray absorption data from the bulk and surfaces of solids and liquids. In this chapter, we will give the basic principles of XAS, explain the information content of essentially two different aspects of the absorption process leading to EXAFS and XANES, and discuss the source and samples limitations

  7. In situ X-ray absorption spectroscopy of transition metal based water oxidation catalysts

    NARCIS (Netherlands)

    van Oversteeg, Christina H M|info:eu-repo/dai/nl/413490483; Doan, Hoang Q; de Groot, Frank M F|info:eu-repo/dai/nl/08747610X; Cuk, Tanja

    2016-01-01

    X-ray absorption studies of the geometric and electronic structure of primarily heterogeneous Co, Ni, and Mn based water oxidation catalysts are reviewed. The X-ray absorption near edge and extended X-ray absorption fine structure studies of the metal K-edge, characterize the metal oxidation state,

  8. Absorption of Sunlight by Water Vapor in Cloudy Conditions: A Partial Explaination for the Cloud Absorption Anomaly

    Science.gov (United States)

    Crisp, D.

    1996-01-01

    The atmospheric radiative transfer algorithms used in most global general circulation models underestimate the globally-averaged solar energy absorbed by cloudy atmospheres by up to 25 Wm(sup -2)...Here, a sophisticated atmospheric radiative transfer model was used to provide a more comprehensive description of the physical processes that contribute to the absorption of solar radiation by the Earth's atmosphere.

  9. Absorption heat pumps

    Science.gov (United States)

    Huhtinen, M.; Heikkilae, M.; Andersson, R.

    1987-03-01

    The aim of the study was to analyze the technical and economic feasibility of absorption heat pumps in Finland. The work was done as a case study: the technical and economic analyses have been carried out for six different cases, where in each the suitable size and type of the heat pump plant and the auxiliary components and connections were specified. The study also detailed the costs concerning the procurement, installation and test runs of the machinery, as well as the savings in energy costs incurred by the introduction of the plant. Conclusions were drawn of the economic viability of the applications studied. The following cases were analyzed: heat recovery from flue gases and productin of district heat in plants using peat, natural gas, and municipal wastes as a fuel. Heat recovery in the pulp and paper industry for the upgrading of pressure of secondary steam and for the heating of white liquor and combustion and drying the air. Heat recovery in a peat-fulled heat and power plant from flue gases that have been used for the drying of peat. According to the study, the absorption heat pump suits best to the production of district heat, when the heat source is the primary energy is steam produced by the boiler. Included in the flue as condensing is the purification of flue gases. Accordingly, benefit is gained on two levels in thick applications. In heat and power plants the use of absorption heat pumps is less economical, due to the fact that the steam used by the pump reduces the production of electricity, which is rated clearly higher than heat.

  10. Rapidly variable relatvistic absorption

    Science.gov (United States)

    Parker, M.; Pinto, C.; Fabian, A.; Lohfink, A.; Buisson, D.; Alston, W.; Jiang, J.

    2017-10-01

    I will present results from the 1.5Ms XMM-Newton observing campaign on the most X-ray variable AGN, IRAS 13224-3809. We find a series of nine absorption lines with a velocity of 0.24c from an ultra-fast outflow. For the first time, we are able to see extremely rapid variability of the UFO features, and can link this to the X-ray variability from the inner accretion disk. We find a clear flux dependence of the outflow features, suggesting that the wind is ionized by increasing X-ray emission.

  11. The Soret absorption properties of carotenoids and chlorophylls in antenna complexes of higher plants

    NARCIS (Netherlands)

    Croce, Roberta; Cinque, Gianfelice; Holzwarth, Alfred R.; Bassi, Roberto

    2000-01-01

    The absorption spectra of two light harvesting complexes from higher plants, CP29 and LHC II, have been analysed in the Soret region in order to obtain a description in terms of the absorption spectra of the individual pigments. This information is of great practical use when applying spectroscopic

  12. Pondermotive absorption of a short intense laser pulse in a non-uniform plasma

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, A.A.; Platonov, K.Yu. [Inst. for Laser Physics, SC `Vavilov State Optical Inst.` 12, Birzhevaya line, St Petersburg (Russian Federation); Tanaka, K.A.

    1998-03-01

    An analytical description of the pondermotive absorption mechanism at a short high intense laser pulse interaction with a strong inhomogeneous plasma is presented. The optimal conditions for the maximum of resonance absorption of laser pulse interaction with non-uniform plasma at normal incidence are founded. (author)

  13. Description logics of context

    CSIR Research Space (South Africa)

    Klarman, S

    2013-05-01

    Full Text Available We introduce Description Logics of Context (DLCs) - an extension of Description Logics (DLs) for context-based reasoning. Our approach descends from J. McCarthy's tradition of treating contexts as formal objects over which one can quantify...

  14. Physics 3204. Course Description.

    Science.gov (United States)

    Newfoundland and Labrador Dept. of Education.

    A description of the physics 3204 course in Newfoundland and Labrador is provided. The description includes: (1) statement of purpose, including general objectives of science education; (2) a list of six course objectives; (3) course content for units on sound, light, optical instruments, electrostatics, current electricity, Michael Faraday and…

  15. Descriptive set theory

    CERN Document Server

    Moschovakis, YN

    1987-01-01

    Now available in paperback, this monograph is a self-contained exposition of the main results and methods of descriptive set theory. It develops all the necessary background material from logic and recursion theory, and treats both classical descriptive set theory and the effective theory developed by logicians.

  16. Development of a portable cavity-enhanced absorption spectrometer for the measurement of ambient NO3 and N2O5: experimental setup, lab characterizations, and field applications in a polluted urban environment

    Science.gov (United States)

    Wang, Haichao; Chen, Jun; Lu, Keding

    2017-04-01

    A small and portable incoherent broadband cavity-enhanced absorption spectrometer (IBBCEAS) for NO3 and N2O5 measurement has been developed. The instrument features a mechanically aligned non-adjustable optical mounting system, and the novel design of the optical mounting system enables a fast setup and stable operation in field applications. To remove the influence of the strong nonlinear absorption by water vapour, a dynamic reference spectrum through NO titration is used for the spectrum analysis. The wall loss effects of the sample system were extensively studied, and the total transmission efficiencies were determined to be 85 and 55 % for N2O5 and NO3, respectively, for our experimental setup. The limit of detection (LOD) was estimated to be 2.4 pptv (1σ) and 2.7 pptv (1σ) at 1 s intervals for NO3 and N2O5, respectively. The associated uncertainty of the field measurement was estimated to be 19 % for NO3 and 22-36 % for N2O5 measurements from the uncertainties of transmission efficiency, absorption cross section, effective cavity length, and mirror reflectivity. The instrument was successfully deployed in two comprehensive field campaigns conducted in the winter and summer of 2016 in Beijing. Up to 1.0 ppb NO3+N2O5 was observed with the presence of high aerosol loadings, which indicates an active night-time chemistry in Beijing.

  17. Exercise, Insulin Absorption Rates, and Artificial Pancreas Control

    Science.gov (United States)

    Frank, Spencer; Hinshaw, Ling; Basu, Rita; Basu, Ananda; Szeri, Andrew J.

    2016-11-01

    Type 1 Diabetes is characterized by an inability of a person to endogenously produce the hormone insulin. Because of this, insulin must be injected - usually subcutaneously. The size of the injected dose and the rate at which the dose reaches the circulatory system have a profound effect on the ability to control glucose excursions, and therefore control of diabetes. However, insulin absorption rates via subcutaneous injection are variable and depend on a number of factors including tissue perfusion, physical activity (vasodilation, increased capillary throughput), and other tissue geometric and physical properties. Exercise may also have a sizeable effect on the rate of insulin absorption, which can potentially lead to dangerous glucose levels. Insulin-dosing algorithms, as implemented in an artificial pancreas controller, should account accurately for absorption rate variability and exercise effects on insulin absorption. The aforementioned factors affecting insulin absorption will be discussed within the context of both fluid mechanics and data driven modeling approaches.

  18. On Meanings and Descriptions

    Directory of Open Access Journals (Sweden)

    Mieke Bal

    1981-09-01

    Full Text Available Although descriptive passages would appear to be of marginal importance in narrative texts, they are, in fact, of both logical and semantic necessity. Narratology, therefore, must take these segments into account. In this article, I shall survey the present situation in this field and compare rival points of view. I shall also offer several suggestions for analyzing descriptions. The following topics will be discussed: the nature of description as a specific type of discourse which makes it recognizable as such; the internal structure of description; the place and function of descriptions in the text as a whole. In the latter section, the semantic impact of descriptions in the overall meaning of narrative texts will be accounted for. This article is intended as a contribution to the theory of description as a part of narratology. It also has a didactic purpose, since it proposes a model for the analysis of texts which can be used for systematic text-study, both in a historical and a comparative perspective.

  19. MULTIMAGNON ABSORPTION IN MNF2-OPTICAL ABSORPTION SPECTRUM.

    Science.gov (United States)

    The absorption spectrum of MnF2 at 4.2K in the 3900A region was measured in zero external fields and in high fields. Exciton lines with magnon ...sidebands are observed, accompanied by a large number of weak satellite lines. Results on the exciton and magnon absorptions are similar to those of...McClure et al. The satellite lines are interpreted as being multi- magnon absorptions, and it is possible to fit the energy of all the absorptions with

  20. Analyzing Water's Optical Absorption

    Science.gov (United States)

    2002-01-01

    A cooperative agreement between World Precision Instruments (WPI), Inc., and Stennis Space Center has led the UltraPath(TM) device, which provides a more efficient method for analyzing the optical absorption of water samples at sea. UltraPath is a unique, high-performance absorbance spectrophotometer with user-selectable light path lengths. It is an ideal tool for any study requiring precise and highly sensitive spectroscopic determination of analytes, either in the laboratory or the field. As a low-cost, rugged, and portable system capable of high- sensitivity measurements in widely divergent waters, UltraPath will help scientists examine the role that coastal ocean environments play in the global carbon cycle. UltraPath(TM) is a trademark of World Precision Instruments, Inc. LWCC(TM) is a trademark of World Precision Instruments, Inc.

  1. Atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Haswell, S.J.

    1991-01-01

    Atomic absorption spectroscopy is now well established and widely used technique for the determination of trace and major elements in a wide range analyte types. There have been many advances in the atomic spectroscopy over the last decade and for this reason and to meet the demand, it was felt that there was a need for an updated book. Whilst interest in instrumental design has tended to dominate the minds of the spectrocopist, the analyst concerned with obtaining reliable and representative data, in diverse areas of application, has been diligently modifying and developing sample treatment and instrumental introduction techniques. Such methodology is de fundamental part of analysis and form the basis of the fourteen application chapters of this book. The text focuses in the main on AAS; however, the sample handling techniques described are in many cases equally applicable to ICP-OES and ICP-MS analysis. (author). refs.; figs.; tabs

  2. Museum audio description

    OpenAIRE

    Martins, Cláudia Susana Nunes

    2011-01-01

    Audio description for the blind and visually impaired has been around since people have described what is seen. Throughout time, it has evolved and developed within different media, starting with reality and daily life, moving into the cinema and television, then across other performing arts, museums and art galleries, and public places. Thus, academics and entertainment providers have developed a growing interest for audio description, especially in what concerns the best methods and strateg...

  3. Nonlinear effects in collective absorption

    International Nuclear Information System (INIS)

    Uenoyama, Takeshi; Mima, Kunioki; Watanabe, Tsuguhiro.

    1981-01-01

    The collective absorption of high intensity laser radiation is analyzed numerically. Density profile modification due to the ponderomotive force associating laser radiation and the excited electron plasma waves is self-consistently taken into account, and the intensity dependences of the absorption efficiency are obtained. In the high intensity regime, the absorption efficiency is found to be strongly enhanced in the plasma without flow, but reduced with supersonic flow. (author)

  4. Atomic absorption spectrophotometry in perspective

    International Nuclear Information System (INIS)

    Soffiantini, V.

    1981-01-01

    Atomic absorption spectrophotometry is essentially an analytical technique used for quantitative trace metal analysis in a variety of materials. The speed and specificity of the technique is its greatest advantage over other analytical techniques. What atomic absorption spectrophotometry can and cannot do and its advantages and disadvantages are discussed, a summary of operating instructions are given, as well as a summary of analytical interferences. The applications of atomic absorption spectrophotometry are also shortly discussed

  5. Reliability of semiology description.

    Science.gov (United States)

    Heo, Jae-Hyeok; Kim, Dong Wook; Lee, Seo-Young; Cho, Jinwhan; Lee, Sang-Kun; Nam, Hyunwoo

    2008-01-01

    Seizure semiology is important for classifying patients' epilepsy. Physicians usually get most of the seizure information from observers though there have been few reports on the reliability of the observers' description. This study aims at determining the reliability of observers' description of the semiology. We included 92 patients who had their habitual seizures recorded during video-EEG monitoring. We compared the semiology described by the observers with that recorded on the videotape, and reviewed which characteristics of the observers affected the reliability of their reported data. The classification of seizures and the individual components of the semiology based only on the observer-description was somewhat discordant compared with the findings from the videotape (correct classification, 85%). The descriptions of some ictal behaviors such as oroalimentary automatism, tonic/dystonic limb posturing, and head versions were relatively accurate, but those of motionless staring and hand automatism were less accurate. The specified directions by the observers were relatively correct. The accuracy of the description was related to the educational level of the observers. Much of the information described by well-educated observers is reliable. However, every physician should keep in mind the limitations of this information and use this information cautiously.

  6. Phytases for improved iron absorption

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Meyer, Anne S.

    2016-01-01

    Phytase enzymes present an alternative to iron supplements, because they have been shown to improve iron absorption by means of catalysing the degradation of a potent iron absorption inhibitor: phytic acid. Phytic acid is a hexaphosphate of inositol and is particularly prevalent in cereal grains...

  7. Multifunctional hybrids for electromagnetic absorption

    Energy Technology Data Exchange (ETDEWEB)

    Huynen, I. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Quievy, N. [Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bailly, C. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bollen, P. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Detrembleur, C. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium); Eggermont, S.; Molenberg, I. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Thomassin, J.M.; Urbanczyk, L. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium)

    2011-05-15

    Highlights: > EM absorption requires low dielectric constant and {approx}1 S/m electrical conductivity. > New hybrids were processed with CNT-filled polymer foam inserted in Al honeycomb. > The EM absorption in the GHz range is superior to any known material. > A closed form model is used to guide the design of the hybrid. > The architectured material is light with potential for thermal management. - Abstract: Electromagnetic (EM) interferences are ubiquitous in modern technologies and impact on the reliability of electronic devices and on living cells. Shielding by EM absorption, which is preferable over reflection in certain instances, requires combining a low dielectric constant with high electrical conductivity, which are antagonist properties in the world of materials. A novel class of hybrid materials for EM absorption in the gigahertz range has been developed based on a hierarchical architecture involving a metallic honeycomb filled with a carbon nanotube-reinforced polymer foam. The waveguide characteristics of the honeycomb combined with the performance of the foam lead to unexpectedly large EM power absorption over a wide frequency range, superior to any known material. The peak absorption frequency can be tuned by varying the shape of the honeycomb unit cell. A closed form model of the EM reflection and absorption provides a tool for the optimization of the hybrid. This designed material sets the stage for a new class of sandwich panels combining high EM absorption with mass efficiency, stiffness and thermal management.

  8. Optical absorption of irradiated carbohydrates

    International Nuclear Information System (INIS)

    Supe, A.A.; Tiliks, Yu.E.

    1994-01-01

    The optical absorption spectra of γ-irradiated carbohydrates (glucose, lactose, sucrose, maltose, and starch) and their aqueous solutions were studied. The comparison of the data obtained with the determination of the concentrations of molecular and radical products of radiolysis allows the absorption bands with maxima at 250 and 310 nm to be assigned to the radicals trapped in the irradiated carbohydrates

  9. Water absorption in brick masonry

    NARCIS (Netherlands)

    Brocken, H.J.P.; Smolders, H.R.

    1996-01-01

    The water absorption in brick, mortar that was cured separately, and masonry samples was studied using NMR. Models of the moisture transport are usually formulated on the basis of a diffusion equation. In the case of water absorption in separate brick and mortar samples, the moisture diffusivity in

  10. Multifunctional hybrids for electromagnetic absorption

    International Nuclear Information System (INIS)

    Huynen, I.; Quievy, N.; Bailly, C.; Bollen, P.; Detrembleur, C.; Eggermont, S.; Molenberg, I.; Thomassin, J.M.; Urbanczyk, L.

    2011-01-01

    Highlights: → EM absorption requires low dielectric constant and ∼1 S/m electrical conductivity. → New hybrids were processed with CNT-filled polymer foam inserted in Al honeycomb. → The EM absorption in the GHz range is superior to any known material. → A closed form model is used to guide the design of the hybrid. → The architectured material is light with potential for thermal management. - Abstract: Electromagnetic (EM) interferences are ubiquitous in modern technologies and impact on the reliability of electronic devices and on living cells. Shielding by EM absorption, which is preferable over reflection in certain instances, requires combining a low dielectric constant with high electrical conductivity, which are antagonist properties in the world of materials. A novel class of hybrid materials for EM absorption in the gigahertz range has been developed based on a hierarchical architecture involving a metallic honeycomb filled with a carbon nanotube-reinforced polymer foam. The waveguide characteristics of the honeycomb combined with the performance of the foam lead to unexpectedly large EM power absorption over a wide frequency range, superior to any known material. The peak absorption frequency can be tuned by varying the shape of the honeycomb unit cell. A closed form model of the EM reflection and absorption provides a tool for the optimization of the hybrid. This designed material sets the stage for a new class of sandwich panels combining high EM absorption with mass efficiency, stiffness and thermal management.

  11. Atmospheric absorption of sound - Update

    Science.gov (United States)

    Bass, H. E.; Sutherland, L. C.; Zuckerwar, A. J.

    1990-01-01

    Best current expressions for the vibrational relaxation times of oxygen and nitrogen in the atmosphere are used to compute total absorption. The resulting graphs of total absorption as a function of frequency for different humidities should be used in lieu of the graph published earlier by Evans et al (1972).

  12. Intestinal Absorption of Thyroid Hormone

    NARCIS (Netherlands)

    N. Kelderman-Bolk (Nienke)

    2015-01-01

    textabstractIn this thesis the treatment of hypothyroidism and absorption of T4 is described from a clinical and basic point of view. Put together the thesis gives insight in the factors influencing LT4 absorption and its results have influenced the timing of LT4 intake.

  13. Intestinal absorption of fluorescently labeled nanoparticles.

    Science.gov (United States)

    Simovic, Spomenka; Song, Yunmei; Nann, Thomas; Desai, Tejal A

    2015-07-01

    Characterization of intestinal absorption of nanoparticles is critical in the design of noninvasive anticancer, protein-based, and gene nanoparticle-based therapeutics. Here we demonstrate a general approach for the characterization of the intestinal absorption of nanoparticles and for understanding the mechanisms active in their processing within healthy intestinal cells. It is generally accepted that the cellular processing represents a major drawback of current nanoparticle-based therapeutic systems. In particular, endolysosomal trafficking causes degradation of therapeutic molecules such as proteins, lipids, acid-sensitive anticancer drugs, and genes. To date, investigations into nanoparticle processing within intestinal cells have studied mass transport through Caco-2 cells or everted rat intestinal sac models. We developed an approach to visualize directly the mechanisms of nanoparticle processing within intestinal tissue. These results clearly identify a mechanism by which healthy intestinal cells process nanoparticles and point to the possible use of this approach in the design of noninvasive nanoparticle-based therapies. Advances in nanomedicine have resulted in the development of new therapies for various diseases. Intestinal route of administration remains the easiest and most natural. The authors here designed experiments to explore and characterize the process of nanoparticle transport across the intestinal tissue. In so doing, further insights were gained for future drug design. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Optical absorption of silicon nanowires

    International Nuclear Information System (INIS)

    Xu, T.; Lambert, Y.; Krzeminski, C.; Grandidier, B.; Stiévenard, D.; Lévêque, G.; Akjouj, A.; Pennec, Y.; Djafari-Rouhani, B.

    2012-01-01

    We report on simulations and measurements of the optical absorption of silicon nanowires (NWs) versus their diameter. We first address the simulation of the optical absorption based on two different theoretical methods: the first one, based on the Green function formalism, is useful to calculate the scattering and absorption properties of a single or a finite set of NWs. The second one, based on the finite difference time domain (FDTD) method, is well-adapted to deal with a periodic set of NWs. In both cases, an increase of the onset energy for the absorption is found with increasing diameter. Such effect is experimentally illustrated, when photoconductivity measurements are performed on single tapered Si nanowires connected between a set of several electrodes. An increase of the nanowire diameter reveals a spectral shift of the photocurrent intensity peak towards lower photon energies that allow to tune the absorption onset from the ultraviolet radiations to the visible light spectrum.

  15. Olkiluoto site description 2011

    International Nuclear Information System (INIS)

    2012-12-01

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties

  16. CRAC2 model description

    International Nuclear Information System (INIS)

    Ritchie, L.T.; Alpert, D.J.; Burke, R.P.; Johnson, J.D.; Ostmeyer, R.M.; Aldrich, D.C.; Blond, R.M.

    1984-03-01

    The CRAC2 computer code is a revised version of CRAC (Calculation of Reactor Accident Consequences) which was developed for the Reactor Safety Study. This document provides an overview of the CRAC2 code and a description of each of the models used. Significant improvements incorporated into CRAC2 include an improved weather sequence sampling technique, a new evacuation model, and new output capabilities. In addition, refinements have been made to the atmospheric transport and deposition model. Details of the modeling differences between CRAC2 and CRAC are emphasized in the model descriptions

  17. Olkiluoto site description 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties.

  18. Generalizing: The descriptive struggle

    Directory of Open Access Journals (Sweden)

    Barney G. Glaser, Ph.D.; Hon Ph.D.

    2006-11-01

    Full Text Available The literature is not kind to the use of descriptive generalizations. Authors struggle and struggle to find and rationalize a way to use them and then fail in spite of trying a myriad of work-arounds. And then we have Lincoln and Guba’s famous statement: “The only generalization is: there is no generalization” in referring to qualitative research. (op cit, p. 110 They are referring to routine QDA yielding extensive descriptions, but which tacitly include conceptual generalizations without any real thought of knowledge about them. In this chapter I wish to explore this struggle for the purpose of explaining that the various contra arguments to using descriptive generalizations DO NOT apply to the ease of using conceptual generalizations yielded in SGT and especially FGT. I will not argue for the use of descriptive generalization. I agree with Lincoln and Guba with respect to QDA, “the only generalization is: there is no generalization.” It is up to the QDA methodologists, of whom there are many; to continue the struggle and I wish them well.

  19. Tore Supra: technical description

    International Nuclear Information System (INIS)

    1985-08-01

    This report is aimed, after a brief recall of physics and technologic perspectives of Tore Supra, at giving a detailed description of the basic machine; details of each component are defined. Volume 1 is specifically concerned with the general aspects of Tore Supra and the toroidal field system [fr

  20. Systematic Description of Sensors

    NARCIS (Netherlands)

    Regtien, Paulus P.L.; Sydenham, Peter H.; Thorn, Richard

    A sensor performs the exchange of information (thus energy) from one domain to another and therefore it operates on the interface between different physical domains. Several frameworks have been developed for a systematic description of sensors. Basically, they are based on either of two different

  1. Fractal description of fractures

    International Nuclear Information System (INIS)

    Lung, C.W.

    1991-06-01

    Recent studies on the fractal description of fractures are reviewed. Some problems on this subject are discussed. It seems hopeful to use the fractal dimension as a parameter for quantitative fractography and to apply fractal structures to the development of high toughness materials. (author). 28 refs, 7 figs

  2. MCFire model technical description

    Science.gov (United States)

    David R. Conklin; James M. Lenihan; Dominique Bachelet; Ronald P. Neilson; John B. Kim

    2016-01-01

    MCFire is a computer program that simulates the occurrence and effects of wildfire on natural vegetation, as a submodel within the MC1 dynamic global vegetation model. This report is a technical description of the algorithms and parameter values used in MCFire, intended to encapsulate its design and features a higher level that is more conceptual than the level...

  3. Dry Cleaning, Course Description.

    Science.gov (United States)

    Briscoe, Albert J.; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center which was established to teach high school dropouts and/or hard-core unemployed youth. The ultimate objectives of this course are to prepare students for employment in dry cleaning occupations and to assist them in completing their high school graduation…

  4. Business Education, Course Description.

    Science.gov (United States)

    O'Neill, Robert; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center in teaching high school dropouts and hard-core unemployed youth. The ultimate objectives of the business education curriculum at the Center are to prepare students for employment in clerical occupations and to assist them in completing their high school…

  5. Communications, Course Description.

    Science.gov (United States)

    Vickstrom, Sandra E.; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center which was established to teach high school dropouts and/or hardcore unemployed youth. The ultimate objectives of this curriculum are to develop communicative skills necessary for social interaction and to help the student complete high school graduation…

  6. Reading, Course Description.

    Science.gov (United States)

    Decker, George; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center which was established to teach high school dropouts and hard-core unemployed youth. The objectives of this reading curriculum are to develop skills of retarded readers, further develop skills of adequate readers, and develop an appreciation for reading.…

  7. Updating action domain descriptions.

    Science.gov (United States)

    Eiter, Thomas; Erdem, Esra; Fink, Michael; Senko, Ján

    2010-10-01

    Incorporating new information into a knowledge base is an important problem which has been widely investigated. In this paper, we study this problem in a formal framework for reasoning about actions and change. In this framework, action domains are described in an action language whose semantics is based on the notion of causality. Unlike the formalisms considered in the related work, this language allows straightforward representation of non-deterministic effects and indirect effects of (possibly concurrent) actions, as well as state constraints; therefore, the updates can be more general than elementary statements. The expressivity of this formalism allows us to study the update of an action domain description with a more general approach compared to related work. First of all, we consider the update of an action description with respect to further criteria, for instance, by ensuring that the updated description entails some observations, assertions, or general domain properties that constitute further constraints that are not expressible in an action description in general. Moreover, our framework allows us to discriminate amongst alternative updates of action domain descriptions and to single out a most preferable one, based on a given preference relation possibly dependent on the specified criteria. We study semantic and computational aspects of the update problem, and establish basic properties of updates as well as a decomposition theorem that gives rise to a divide and conquer approach to updating action descriptions under certain conditions. Furthermore, we study the computational complexity of decision problems around computing solutions, both for the generic setting and for two particular preference relations, viz. set-inclusion and weight-based preference. While deciding the existence of solutions and recognizing solutions are PSPACE-complete problems in general, the problems fall back into the polynomial hierarchy under restrictions on the additional

  8. Subgap Absorption in Conjugated Polymers

    Science.gov (United States)

    Sinclair, M.; Seager, C. H.; McBranch, D.; Heeger, A. J; Baker, G. L.

    1991-01-01

    Along with X{sup (3)}, the magnitude of the optical absorption in the transparent window below the principal absorption edge is an important parameter which will ultimately determine the utility of conjugated polymers in active integrated optical devices. With an absorptance sensitivity of materials. We have used PDS to measure the optical absorption spectra of the conjugated polymers poly(1,4-phenylene-vinylene) (and derivitives) and polydiacetylene-4BCMU in the spectral region from 0.55 eV to 3 eV. Our spectra show that the shape of the absorption edge varies considerably from polymer to polymer, with polydiacetylene-4BCMU having the steepest absorption edge. The minimum absorption coefficients measured varied somewhat with sample age and quality, but were typically in the range 1 cm{sup {minus}1} to 10 cm{sup {minus}1}. In the region below 1 eV, overtones of C-H stretching modes were observed, indicating that further improvements in transparency in this spectral region might be achieved via deuteration of fluorination.

  9. Sabine absorption coefficients to random incidence absorption coefficients

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2014-01-01

    into random incidence absorption coefficients for porous absorbers are investigated. Two optimization-based conversion methods are suggested: the surface impedance estimation for locally reacting absorbers and the flow resistivity estimation for extendedly reacting absorbers. The suggested conversion methods...

  10. Absorption factor for cylindrical samples

    International Nuclear Information System (INIS)

    Sears, V.F.

    1984-01-01

    The absorption factor for the scattering of X-rays or neutrons in cylindrical samples is calculated by numerical integration for the case in which the absorption coefficients of the incident and scattered beams are not equal. An extensive table of values having an absolute accuracy of 10 -4 is given in a companion report [Sears (1983). Atomic Energy of Canada Limited, Report No. AECL-8176]. In the present paper an asymptotic expression is derived for the absorption factor which can be used with an error of less than 10 -3 for most cases of interest in both neutron inelastic scattering and neutron diffraction in crystals. (Auth.)

  11. Inhibiting Cholesterol Absorption During Lactation Programs Future Intestinal Absorption of Cholesterol in Adult Mice.

    Science.gov (United States)

    Dimova, Lidiya G; de Boer, Jan Freark; Plantinga, Josee; Plösch, Torsten; Hoekstra, Menno; Verkade, Henkjan J; Tietge, Uwe J F

    2017-08-01

    In nematodes, the intestine senses and integrates early life dietary cues that lead to lifelong epigenetic adaptations to a perceived nutritional environment-it is not clear whether this process occurs in mammals. We aimed to establish a mouse model of reduced dietary cholesterol availability from maternal milk and investigate the consequences of decreased milk cholesterol availability, early in life, on the metabolism of cholesterol in adult mice. We blocked intestinal absorption of cholesterol in milk fed to newborn mice by supplementing the food of dams (for 3 weeks between birth and weaning) with ezetimibe, which is secreted into milk. Ezetimibe interacts with the intestinal cholesterol absorption transporter NPC1l1 to block cholesterol uptake into enterocytes. Characterization of these offspring at 24 weeks of age showed a 27% decrease in cholesterol absorption (P intestine. We observed increased histone H3K9me3 methylation at positions -423 to -607 of the proximal Npc1l1 promoter in small intestine tissues from 24-week-old offspring fed ezetimibe during lactation, compared with controls. These findings show that the early postnatal mammalian intestine functions as an environmental sensor of nutritional conditions, responding to conditions such as low cholesterol levels by epigenetic modifications of genes. Further studies are needed to determine how decreased sterol absorption for a defined period might activate epigenetic regulators; the findings of our study might have implications for human infant nutrition and understanding and preventing cardiometabolic disease. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  12. Device Scale Modeling of Solvent Absorption using MFIX-TFM

    Energy Technology Data Exchange (ETDEWEB)

    Carney, Janine E. [National Energy Technology Lab. (NETL), Albany, OR (United States); Finn, Justin R. [National Energy Technology Lab. (NETL), Albany, OR (United States); Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)

    2016-10-01

    Recent climate change is largely attributed to greenhouse gases (e.g., carbon dioxide, methane) and fossil fuels account for a large majority of global CO2 emissions. That said, fossil fuels will continue to play a significant role in the generation of power for the foreseeable future. The extent to which CO2 is emitted needs to be reduced, however, carbon capture and sequestration are also necessary actions to tackle climate change. Different approaches exist for CO2 capture including both post-combustion and pre-combustion technologies, oxy-fuel combustion and/or chemical looping combustion. The focus of this effort is on post-combustion solvent-absorption technology. To apply CO2 technologies at commercial scale, the availability and maturity and the potential for scalability of that technology need to be considered. Solvent absorption is a proven technology but not at the scale needed by typical power plant. The scale up and down and design of laboratory and commercial packed bed reactors depends heavily on the specific knowledge of two-phase pressure drop, liquid holdup, the wetting efficiency and mass transfer efficiency as a function of operating conditions. Simple scaling rules often fail to provide proper design. Conventional reactor design modeling approaches will generally characterize complex non-ideal flow and mixing patterns using simplified and/or mechanistic flow assumptions. While there are varying levels of complexity used within these approaches, none of these models resolve the local velocity fields. Consequently, they are unable to account for important design factors such as flow maldistribution and channeling from a fundamental perspective. Ideally design would be aided by development of predictive models based on truer representation of the physical and chemical processes that occur at different scales. Computational fluid dynamic (CFD) models are based on multidimensional flow equations with first

  13. Oral and Written Picture Description in Individuals with Aphasia

    Science.gov (United States)

    Vandenborre, Dorien; Visch-Brink, Evy; van Dun, Kim; Verhoeven, Jo; Mariën, Peter

    2018-01-01

    Background: Aphasia is characterized by difficulties in connected speech/writing. Aims: To explore the differences between the oral and written description of a picture in individuals with chronic aphasia (IWA) and healthy controls. Descriptions were controlled for productivity, efficiency, grammatical organization, substitution behaviour and…

  14. Metamaterials for perfect absorption

    CERN Document Server

    Lee, Young Pak; Yoo, Young Joon; Kim, Ki Won

    2016-01-01

    This book provides a comprehensive overview of the theory and practical development of metamaterial-based perfect absorbers (MMPAs). It begins with a brief history of MMPAs which reviews the various theoretical and experimental milestones in their development. The theoretical background and fundamental working principles of MMPAs are then discussed, providing the necessary background on how MMPAs work and are constructed. There then follows a section describing how different MMPAs are designed and built according to the operating frequency of the electromagnetic wave, and how their behavior is changed. Methods of fabricating and characterizing MMPAs are then presented. The book elaborates on the performance and characteristics of MMPAs, including electromagnetically-induced transparency (EIT). It also covers recent advances in MMPAs and their applications, including multi-band, broadband, tunability, polarization independence and incidence independence. Suitable for graduate students in optical sciences and e...

  15. X-ray spectroscopic characterization of laser produced hot dense plasmas

    International Nuclear Information System (INIS)

    Kontogiannopoulos, N.

    2007-12-01

    In this work we performed experiments of emission and absorption spectroscopy of laser produced plasmas, to provide well characterized spectral data which permit to benchmark atomic physics codes. More precisely, we produced xenon and krypton plasmas in NLTE (non local thermodynamic equilibrium) conditions and studied their emission spectra. In a second experiment, we characterized the absorption spectra of zinc sulfide and aluminium plasmas in LTE (local thermodynamic equilibrium) conditions.The first two chapters give an outline of the theory involved in the study of the emission and absorption plasma spectroscopy. Chapter 1 describes the different atomic processes occurring in a plasma. The LTE and the NLTE statistics ruling the equilibrium of the atomic processes are presented. Then, we give a brief description of the different codes of plasma atomic physics used in the analysis of our experimental data, namely HULLAC, SCO and TRANSPEC/AVERROES. In Chapter 2 the macroscopic theory of the radiation transport through a plasma is given. We describe also the self-similar model of Basko and the view factor approach, which permits us to calculate the heating conditions of the absorption foils achieved in the interior of the spherical gold cavity. Chapter 3 gives a description of the instruments used for realizing the two experiments, as well as the technical characteristics of the LULI2000 laser facility used to perform the experiments. Chapter 4 presents the experiment realized to characterize the emission spectra of the xenon and krypton plasmas in NLTE, as well the analysis of the experimental data with TRANSPEC/AVERROES. Finally, the experiment for measuring the absorption spectrum of the ZnS plasma mixture and the analysis of the experimental data with the code SCO are given in Chapter 5

  16. Multidimensional nonlinear descriptive analysis

    CERN Document Server

    Nishisato, Shizuhiko

    2006-01-01

    Quantification of categorical, or non-numerical, data is a problem that scientists face across a wide range of disciplines. Exploring data analysis in various areas of research, such as the social sciences and biology, Multidimensional Nonlinear Descriptive Analysis presents methods for analyzing categorical data that are not necessarily sampled randomly from a normal population and often involve nonlinear relations. This reference not only provides an overview of multidimensional nonlinear descriptive analysis (MUNDA) of discrete data, it also offers new results in a variety of fields. The first part of the book covers conceptual and technical preliminaries needed to understand the data analysis in subsequent chapters. The next two parts contain applications of MUNDA to diverse data types, with each chapter devoted to one type of categorical data, a brief historical comment, and basic skills peculiar to the data types. The final part examines several problems and then concludes with suggestions for futu...

  17. Descriptive sensory evaluations

    DEFF Research Database (Denmark)

    Dehlholm, Christian

    in projective mapping frame geometry and restrictions on the reported semantics. Two rapid descriptive evaluation techniques were proposed to represent a consensus evaluation. One of the approaches, ‘consensus attribute rating’ (CAR), allows a group of assessors to rate products on a list of pre......-selected attributes. The other approach, ‘consensus Napping’, allows a group of assessors to project products according to an agreed consensus placement on a paper sheet. Evaluations were performed either by groups of experienced sensory assessors or by product experts. Compared with conventional profiling techniques......, the evaluations showed significant correlations between some product configurations, but no consistent and systematic similarities. On average, product expert groups had less in common with the reference profiles than the trained panellist groups and the semantic descriptions of products varied to a large degree...

  18. Descriptive sensory evaluations

    DEFF Research Database (Denmark)

    Dehlholm, Christian

    A recent trend in descriptive sensory evaluation methodology has been the application of rapid evaluation techniques. The ease in use makes the techniques extremely easy to implement by industry and university environments. Thus, one might not consider validity in the choice of method. The overall...... in projective mapping frame geometry and restrictions on the reported semantics. Two rapid descriptive evaluation techniques were proposed to represent a consensus evaluation. One of the approaches, ‘consensus attribute rating’ (CAR), allows a group of assessors to rate products on a list of pre...... for all groups. Hence, consensus profiling with untrained assessors should not be used for the purpose of considering consistency between panels, while assessors trained in the product may perform more reliably. As for projective mapping variations of frame geometry, evaluations in a rectangular...

  19. Resource Description Framework (RDF)

    OpenAIRE

    Gibbins, Nicholas; Shadbolt, Nigel

    2009-01-01

    The Resource Description Framework (RDF) is the standard knowledge representation language for the Semantic Web, an evolution of the World Wide Web that aims to provide a well-founded infrastructure for publishing, sharing and querying structured data. This article provides an introduction to RDF and its related vocabulary definition language RDF Schema, and explains its relationship with the OWL Web Ontology Language. Finally, it provides an overview of the historical development of RDF and ...

  20. TMACS system description

    International Nuclear Information System (INIS)

    Scaief, C.C.

    1995-01-01

    This document provides a description of the Tank Monitor and Control System (TMACS). It is intended as an introduction for those persons unfamiliar with the system as well as a reference document for the users, maintenance personnel, and system designers. In addition to describing the system, the document outlines the associated drawing documentation, provides maintenance and spare parts information, and discusses other TMACS documents that provide additional detail

  1. Ultrasonic absorption in solid specimens

    International Nuclear Information System (INIS)

    Siwabessy, P.J. W.; Stewart, G.A.

    1996-01-01

    As part of a project to measure the absorption of high frequency (50 - 500 kHz) sonar signals in warm sea-water, a laboratory apparatus has been constructed and tested against room temperature distilled water and various solutions of MgSO 4 (chemical relaxation of MgSO 4 is the major contribution to absorption below 200 kHz). The technique involves monitoring the decay of an acoustic signal for different sizes of vessels of water suspended in an evacuated chamber. So far, all containing vessels used have been spherical in shape. Extrapolation of the results to infinite volume yields the absorption due to the water alone. In order to accommodate variations in temperature and pressure, and to make the system more robust (e.g. for ship deck usage), it is desirable to employ stainless steel vessels. However, it was found that the quality of the data was greatly improved when pyrex glass spheres were used. The stainless steel spheres were manufactured by welding together mechanically spun hemispheres. The linear frequency dependence characteristic of acoustic absorption in solids was observed (in contrast to the quadratic frequency dependence of acoustic absorption in water), and the acoustic absorption was found to depend strongly on the thermal history of the steel

  2. XML Diagnostics Description Standard

    International Nuclear Information System (INIS)

    Neto, A.; Fernandes, H.; Varandas, C.; Lister, J.; Yonekawa, I.

    2006-01-01

    A standard for the self-description of fusion plasma diagnostics will be presented, based on the Extensible Markup Language (XML). The motivation is to maintain and organise the information on all the components of a laboratory experiment, from the hardware to the access security, to save time and money when problems arises. Since there is no existing standard to organise this kind of information, every Association stores and organises each experiment in different ways. This can lead to severe problems when the organisation schema is poorly documented or written in national languages. The exchange of scientists, researchers and engineers between laboratories is a common practice nowadays. Sometimes they have to install new diagnostics or to update existing ones and frequently they lose a great deal of time trying to understand the currently installed system. The most common problems are: no documentation available; the person who understands it has left; documentation written in the national language. Standardisation is the key to solving all the problems mentioned. From the commercial information on the diagnostic (component supplier; component price) to the hardware description (component specifications; drawings) to the operation of the equipment (finite state machines) through change control (who changed what and when) and internationalisation (information at least in the native language and in English), a common XML schema will be proposed. This paper will also discuss an extension of these ideas to the self-description of ITER plant systems, since the problems will be identical. (author)

  3. Quality Assurance Requirements and Description

    International Nuclear Information System (INIS)

    Ram Murthy

    2002-01-01

    The Quality Assurance Requirements and Description (QARD) is the principal Quality Assurance (QA) document for the Civilian Radioactive Waste Management Program (Program). It establishes the minimum requirements for the QA program [INTRODUCTION :1p2s (NOT A REQUIREMENT)]. The QARD contains regulatory requirements and program commitments necessary for the development of an effective QA program [INTRODUCTION :1p3s (NOT A REQUIREMENT)]. Implementing documents must be based on, and be consistent with the QARD. The QARD applies to the following: (1) Acceptance of spent nuclear fuel and high-level waste. (2) Transport of spent nuclear fuel and high-level waste. (3) Storage of spent nuclear fuel through receipt of storage cask certification or a facility operating license. (4) Monitored Geologic Repository, including the site characterization activities [Exploratory Studies Facility (ESF) and surface based testing], through receipt of an operating license. (5) High-level waste form development through qualification, production, and acceptance. (6) Characterization of DOE spent nuclear fuel, and conditioning through acceptance of DOE spent nuclear fuel. Section 2.0, Quality Assurance Program, defines in greater detail criteria for determining work subject to the QARD

  4. An outdoor investigation of the absorption degradation of single ...

    Indian Academy of Sciences (India)

    thermography was used for mapping the module temperature profile. Fourier transform infrared spectroscopy (FTIR) was used for the absorption characterization. ... The localized heating can cause structural damage which increases surface recombina- tion and reduces the mobility and lifetime of photogenerated electrons.

  5. Characterization of the Cu(Π) and Zn(Π) binding to the Amyloid-β short peptides by both the Extended X-ray Absorption Fine Structure and the Synchrotron Radiation Circular Dichroism spectroscopy

    Science.gov (United States)

    Zhang, Zhiyin; Sun, Shuaishuai; Xu, Jianhua; Zhang, Jing; Huang, Yan; Zhang, Bingbing; Tao, Ye

    2013-04-01

    Alzheimer's disease (AD) is a progressive and devastating neurodegenerative pathology, clinically characterized by dementia, cognitive impairment, personality disorders and memory loss. It is generally accepted that, misfolding of Aβ peptides is the key element in pathogenesis and the secondary structure of Aβ can be changed to major β-strand with reasons unknown yet. Many studies have shown that the misfolding may be linked with some biometals, mainly copper and zinc ions. To characterize interactions of Aβ and metal ions, we utilized both the extended X-ray fine structure spectroscopy (EXAFS) and the synchrotron radiation circular dichroism spectroscopy (SRCD). Aβ (13-22), Aβ (13-21), Aβ (E22G) and Aβ(HH-AA) were selected to study the mechanism of copper and zinc binding to Aβ. We found that Cu interaction with H13 and H14 residues led to the disappearance of the PPΠ, while the Cu binding E22 residue caused a remarkable conformation change to β-sheet enrichment. The Zn ion, in contrast, made little effect on the conformation and it coordinated to only one histidine (H residue) or not.

  6. MCO Monitoring activity description

    International Nuclear Information System (INIS)

    SEXTON, R.A.

    1998-01-01

    Spent Nuclear Fuel remaining from Hanford's N-Reactor operations in the 1970s has been stored under water in the K-Reactor Basins. This fuel will be repackaged, dried and stored in a new facility in the 200E Area. The safety basis for this process of retrieval, drying, and interim storage of the spent fuel has been established. The monitoring of MCOS in dry storage is a currently identified issue in the SNF Project. This plan outlines the key elements of the proposed monitoring activity. Other fuel stored in the K-Reactor Basins, including SPR fuel, will have other monitoring considerations and is not addressed by this activity description

  7. Description logic rules

    CERN Document Server

    Krötzsch, M

    2010-01-01

    Ontological modelling today is applied in many areas of science and technology,including the Semantic Web. The W3C standard OWL defines one of the most important ontology languages based on the semantics of description logics. An alternative is to use rule languages in knowledge modelling, as proposed in the W3C's RIF standard. So far, it has often been unclear how to combine both technologies without sacrificing essential computational properties. This book explains this problem and presents new solutions that have recently been proposed. Extensive introductory chapters provide the necessary

  8. Absorption dynamics and delay time in complex potentials

    Science.gov (United States)

    Villavicencio, Jorge; Romo, Roberto; Hernández-Maldonado, Alberto

    2018-05-01

    The dynamics of absorption is analyzed by using an exactly solvable model that deals with an analytical solution to Schrödinger’s equation for cutoff initial plane waves incident on a complex absorbing potential. A dynamical absorption coefficient which allows us to explore the dynamical loss of particles from the transient to the stationary regime is derived. We find that the absorption process is characterized by the emission of a series of damped periodic pulses in time domain, associated with damped Rabi-type oscillations with a characteristic frequency, ω = (E + ɛ)/ℏ, where E is the energy of the incident waves and ‑ɛ is energy of the quasidiscrete state of the system induced by the absorptive part of the Hamiltonian; the width γ of this resonance governs the amplitude of the pulses. The resemblance of the time-dependent absorption coefficient with a real decay process is discussed, in particular the transition from exponential to nonexponential regimes, a well-known feature of quantum decay. We have also analyzed the effect of the absorptive part of the potential on the dynamical delay time, which behaves differently from the one observed in attractive real delta potentials, exhibiting two regimes: time advance and time delay.

  9. Redefining the Relationship between Intellectual Capital and Innovation: The Mediating Role of Absorptive Capacity

    OpenAIRE

    Cassol, Alessandra; Gonçalo, Cláudio Reis; Ruas, Roberto Lima

    2016-01-01

    Abstract The objective of this study is to analyze the relationship between absorptive capacity, intellectual capital and innovation. The main purpose of this research is to demonstrate that absorptive capacity can leverage the relation between intellectual capital and innovation potential. The method was a single case study using exploratory and descriptive research strategies and applying both quantitative and qualitative techniques. The case study investigated was a Brazilian corporation t...

  10. Transdermic absorption of Melagenina II

    International Nuclear Information System (INIS)

    Hernandez Gonzalez, I.; Martinez Lopez, B.; Ruiz Pena, M.; Caso Pena, R.

    1997-01-01

    The transdermic absorption of Melagenina II (MII) was evaluated. MII was a labelled with 125I by the yodogen method and purified by column chromatography with Sephadex LH-20 in ethanol: water (7:3). In vitro absorption of ( 125I ) - MII thought human skin was carried out in Keshary-Chien modified diffusion cells. Tape stripping method was applied after 24 hours to evaluate the accumulated activity in dermis and epidermis. In vivo assays were performed in Sprague Dawley rats to analyze absorption of MII until 24 hours after a single application and for five days a low penetrability of the drug while in vivo there were not found blood levels significantly greater than zero , nevertheless and important amount of radioactivity was found in feces and urine. The activity was concentrated mainly in the application site in both models

  11. Absorption properties of identical atoms

    International Nuclear Information System (INIS)

    Sancho, Pedro

    2013-01-01

    Emission rates and other optical properties of multi-particle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas. -- Highlights: •The absorption rates of a pair of identical atoms in product and (anti)symmetrized states are different. •The modifications of the optical properties are essentially determined by the overlapping between the atoms. •The absorption properties differ, in some cases, for bosons and fermions

  12. Multiple Descriptions Using Sparse Decompositions

    DEFF Research Database (Denmark)

    Jensen, Tobias Lindstrøm; Østergaard, Jan; Dahl, Joachim

    2010-01-01

    In this paper, we consider the design of multiple descriptions (MDs) using sparse decompositions. In a description erasure channel only a subset of the transmitted descriptions is received. The MD problem concerns the design of the descriptions such that they individually approximate the source...... first-order method to the proposed convex problem such that we can solve large-scale instances for image sequences....

  13. X-ray absorption spectroscopy investigations on radioactive matter using MARS beamline at SOLEIL synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Llorens, Isabelle; Solari, Pier Lorenzo; Sitaud, Bruno [Synchrotron SOLEIL - l' Orme des Merisiers Saint Aubin, Gif-sur-Yvette (France); and others

    2014-07-01

    The MARS beamline at the SOLEIL synchrotron is dedicated to the characterization of radioactive material samples. One great advantage of the beamline is the possibility to characterize about 380 radionuclides by different X-ray techniques in the same place. This facility is unique in Europe. A wide energy range from around 3.5 keV to 36 keV K-edges from K to Cs, and L3 edges from Cd to Am and beyond can be used. The MARS beamline is optimized for X-ray absorption spectroscopy techniques (XANES/EXAFS), powder diffraction (XRD) but X-ray fluorescence (XRF) analysis, High Energy Resolution Fluorescence Detected-XAS (HERFD-XAS), X-ray Emission (XES) and μ-XAS/XRD are also possible. A description of the beamline as well as its performances are given in a first part. Then some scientific examples of XAS studies from users are presented which cover a wide variety of topics in radiochemistry and nuclear materials.

  14. Absorption distances in the dynamical theory of electron diffraction

    International Nuclear Information System (INIS)

    Kamiya, Yoshihiko; Goto, Toshiaki.

    1982-01-01

    The contrast effect of the electron microscopic image at crystal defects is characterized by two parameters; extincion distance and absorption distance. Both quantities are orginally defined for the elastic scattering. Since the inelastic scattering contributes to the electron microscopic image, parameters used for the interpretation of the images are not the same as those for the elastic scattering. It is shown that the difference of absorption distance beteen the theoretical estimation and that used for interpretation is due to the contrst effect of the small angle inelastic scattering. (author)

  15. Aerosol Absorption Measurements in MILAGRO.

    Science.gov (United States)

    Gaffney, J. S.; Marley, N. A.; Arnott, W. P.; Paredes-Miranda, L.; Barnard, J. C.

    2007-12-01

    During the month of March 2006, a number of instruments were used to determine the absorption characteristics of aerosols found in the Mexico City Megacity and nearby Valley of Mexico. These measurements were taken as part of the Department of Energy's Megacity Aerosol Experiment - Mexico City (MAX-Mex) that was carried out in collaboration with the Megacity Interactions: Local and Global Research Observations (MILAGRO) campaign. MILAGRO was a joint effort between the DOE, NSF, NASA, and Mexican agencies aimed at understanding the impacts of a megacity on the urban and regional scale. A super-site was operated at the Instituto Mexicano de Petroleo in Mexico City (designated T-0) and at the Universidad Technologica de Tecamac (designated T-1) that was located about 35 km to the north east of the T-0 site in the State of Mexico. A third site was located at a private rancho in the State of Hidalgo approximately another 35 km to the northeast (designated T-2). Aerosol absorption measurements were taken in real time using a number of instruments at the T-0 and T-1 sites. These included a seven wavelength aethalometer, a multi-angle absorption photometer (MAAP), and a photo-acoustic spectrometer. Aerosol absorption was also derived from spectral radiometers including a multi-filter rotating band spectral radiometer (MFRSR). The results clearly indicate that there is significant aerosol absorption by the aerosols in the Mexico City megacity region. The absorption can lead to single scattering albedo reduction leading to values below 0.5 under some circumstances. The absorption is also found to deviate from that expected for a "well-behaved" soot anticipated from diesel engine emissions, i.e. from a simple 1/lambda wavelength dependence for absorption. Indeed, enhanced absorption is seen in the region of 300-450 nm in many cases, particularly in the afternoon periods indicating that secondary organic aerosols are contributing to the aerosol absorption. This is likely due

  16. Sound absorption property of openpore aluminum foams

    OpenAIRE

    WANG Fang; WANG Lu-cai; WU Jian-guo

    2007-01-01

    This paper presents a study on sound absorption property of aluminum foam by evaluating its sound absorption coefficients using standing wave tube method. Experimental results showed that the average values of sound absorption coefficients (over the test frequency range) are all above 0.4, which indicate very good sound absorption property of the aluminum foams. The sound absorption coefficient is affected by frequency and pore structure, and reaches its maximum value at around 1 000 Hz. With...

  17. Evalutive Descriptions of Art

    Directory of Open Access Journals (Sweden)

    Nataša Lah

    2016-01-01

    Full Text Available Taking into account the fact that, throughout history, certain artworks have been considered as “worth of watching” (according to the Greek etymon ἀξιοϑέατος / aksioteatos, preservation, or theorizing, while others were not, one is led to investigate the various types of evaluative descriptions. Those artworks that are more valuable than others, or simply valuable in themselves on the basis of rather specific features, have always represented the paradigmatic model for the evaluator, thus revealing the identitary nature of value as different from one epoch to another. Our aim has been to discern, with regard to this starting point, the way in which the process of evaluating artworks fits the general matrix of the universal theory of value, with its clearly distinguished levels of evaluation, beginning with value descriptions, continuing through the features of evaluation or abstract qualities of values extracted from these descriptions, and ending with value norms or systems of accepted generalizations in evaluation. Value standpoints in such an evaluation matrix represent dispositions or preferences in procedures, which reflect the norms or signifying concepts of the time. Corresponding procedures, or applications of the hierarchicized signification of artworks, are manifested in all known forms of artwork assessment: attribution, institutionalization, and setting of priorities in terms of exhibition, conservation, acquisition, restoration, and so on. Research in the history of European art-historical ideas has corroborated the hypothesis that, prior to the late 18th century, clear normative patterns were applied when it came to the evaluation of artworks. However, with the emergence of early Romanticism, this could no longer be done in the traditional way. Before the period in question, visual art was created (regardless of some stylistic discrepancies between individual authors and classified according to well-defined thematic

  18. Polemic and Descriptive Negations

    DEFF Research Database (Denmark)

    Horslund, Camilla Søballe

    2011-01-01

    as such may be more or less central to the meaning of the utterance. The present paper investigates the role of morphosyntactic and prosodic prominence as well as register and social setting on the interpretation of negations. It seems plausible to expect that if the negation as such is central to the meaning...... of the utterance (as in polemic negations), the negation will be articulated prominently in order to emphasise this importance. Likewise, if the negation is not central to the meaning of the utterance, it should not be articulated prominently. Moreover, it is plausible to expect descriptive negations to be more...... common in certain social context or genres, while polemic negations are more likely to come up in other genres and social settings. Previous studies have shown a relation between articulatory prominence and register, which may further inform the analysis. Hence, the paper investigates how articulatory...

  19. Task Description Language

    Science.gov (United States)

    Simmons, Reid; Apfelbaum, David

    2005-01-01

    Task Description Language (TDL) is an extension of the C++ programming language that enables programmers to quickly and easily write complex, concurrent computer programs for controlling real-time autonomous systems, including robots and spacecraft. TDL is based on earlier work (circa 1984 through 1989) on the Task Control Architecture (TCA). TDL provides syntactic support for hierarchical task-level control functions, including task decomposition, synchronization, execution monitoring, and exception handling. A Java-language-based compiler transforms TDL programs into pure C++ code that includes calls to a platform-independent task-control-management (TCM) library. TDL has been used to control and coordinate multiple heterogeneous robots in projects sponsored by NASA and the Defense Advanced Research Projects Agency (DARPA). It has also been used in Brazil to control an autonomous airship and in Canada to control a robotic manipulator.

  20. Olkiluoto site description 2004

    International Nuclear Information System (INIS)

    2005-05-01

    This Olkiluoto Site Description 2004 is a description of the Olkiluoto site, in which the various disciplines have been integrated to produce a coherent picture, and is based on the data available prior to the start of the underground excavation of the ONKALO facility. This report is the first version of such a Site Report and supplements the site syntheses that have already been published. Further Site Reports will be produced on a regular basis and it is planned that the Site Report should form the geoscientific basis of the Safety Case in a future licence application. The report updates the Baseline report published in 2003 and is designed to produce an integrated site model, by focusing on interdisciplinary interactions, and also by including new data obtained during 2003 and 2004. The report has been produced by the OMTF (Olkiluoto Modelling Task Force), which covers the areas of geology, rock mechanics, hydrogeology and hydrogeochemistry. In addition to discussing the input from these four disciplines, the Site Report also includes a description of the surface conditions. Formally, the surface conditions are not within the remit of the OMTF, which is concentrating on modelling the bedrock around the ONKALO and the future repository. The influence of the surface conditions to the overall system and to the conditions at depth is recognised, however, and thus a summary of climate, ecosystems and overburden properties is also included in this report. Chapter 1 sets out the methodology to be used in the modelling, describes the various discipline-specific models which are developed and the modelled areas which are used, and also describes two important processes - the prediction/outcome studies and the uncertainty and confidence assessment. The difference between the estimate (the prediction) and the result (the outcome) indicates the level of knowledge and the prevailing uncertainties in the models. Chapter 2 presents the applied investigation data, which are

  1. Bent Electro-Absorption Modulator

    DEFF Research Database (Denmark)

    2002-01-01

    components and the applied electric field in relation to the frequency of the modulated radiation, the bending losses (and possibly coupling losses) will provide extinction of light guided by the bent waveguide section. The refractive index contract may be modulated while keeping the absorption coefficient...... by bendng losses co-operates to provide more compact modulators with improved performance (extinction) and speed....

  2. EVALUATION OF ATOMIC ABSORPTION SPECTROPHOTOMETRY ...

    African Journals Online (AJOL)

    cistvr

    Three commonly used techniques, namely atomic absorption spectrophotometry (AAS-Ashing and. AAS-Non Ashing) and titrimetry (potassium permanganate titration) have been evaluated in this study to determine the calcium content in six food samples whose calcium levels ranged from 0 to more than. 250mg/100g ...

  3. Absorptive capacity and smart companies

    Directory of Open Access Journals (Sweden)

    Patricia Moro González

    2014-12-01

    Full Text Available Purpose: The current competitive environment is substantially modifying the organizations’ learning processes due to a global increase of available information allowing this to be transformed into knowledge. This opportunity has been exploited since the nineties by the tools of “Business Analytics” and “Business Intelligence” but, nevertheless, being integrated in the study of new organizational capacities engaged in the process of creating intelligence inside organizations is still an outstanding task. The review of the concept of absorptive capacity and a detailed study from the perspective of this new reality will be the main objective of study of this paper.Design/methodology/approach: By comparing classical absorptive capacity and absorptive capacity from the point of view of information management tools in each one of the three stages of the organizational learning cycle, some gaps of the former are overcome/fulfilled. The academic/bibliographical references provided in this paper have been obtained from ISI web of knowledge, Scopus and Dialnet data bases, supporting the state of affairs on absorptive capacity and thereafter filtering by "Business Intelligence" and "Business Analytics". Specialized websites and Business Schools` Publications there have also been included, crowning the content on information management tools used that are currently used in the strategic consulting.Findings: Our contribution to the literature is the development of "smart absorptive capacity". This is a new capacity emerging from the reformulation of the classical concept of absorptive capacity wherein some aspects of its definition that might have been omitted are emphasized. The result of this new approach is the creation of a new Theoretical Model of Organizational Intelligence, which aims to explain, within the framework of the Resources and Capabilities Theory, the competitive advantage achieved by the so-called smart companies

  4. Light Absorption By Coated Soot

    Science.gov (United States)

    Sedlacek, A. J.; Lee, J.; Onasch, T. B.; Davidovits, P.; Cross, E. S.

    2009-12-01

    The contribution of aerosol absorption on direct radiative forcing is still an active area of research, in part, because aerosol extinction is dominated by light scattering and, in part, because the primary absorbing aerosol of interest, soot, exhibits complex aging behavior that alters its optical properties. The consequences of this can be evidenced by the work of Ramanathan and Carmichael (2008) who suggest that incorporating the atmospheric heating due to brown clouds will increase black carbon (BC) radiative forcing from the IPCC best estimate of 0.34 Wm-2 (±0.25 Wm-2) (IPCC 2007) to 0.9 Wm-2. This noteworthy degree of the uncertainty is due largely to the interdependence of BC optical properties on particle mixing state and aggregate morphology, each of which changes as the particle ages in the atmosphere and becomes encapsulated within a coating of inorganic and/or organic substances. With the advent of techniques that can directly measure aerosol light absorption without influences due to collection substrate or light scattering (e.g., photoacoustic spectroscopy (Arnott et al., 2005; Lack et al., 2006) and photothermal interferometry (Sedlacek and Lee 2007)) the potential exists for quantifying this interdependence. In July 2008, a laboratory-based measurement campaign, led by Boston College and Aerodyne, was initiated to begin addressing this interdependence. To achieve this objective measurements of both the optical and physical properties of flame-generated soot under nascent, coated and denuded conditions were conducted. In this paper, light absorption by dioctyl sebacate (DOS) encapsulated soot and sulfuric acid coated soot using the technique of photothermal interferometry will be presented. In the case of DOS-coated soot, a monotonic increase in light absorption as a function DOS coating thickness to nearly 100% is observed. This observation is consistent with a coating-induced amplification in particle light absorption. (Bond et al. 2006) However

  5. Laser Irradiated Foam Targets: Absorption and Radiative Properties

    Science.gov (United States)

    Salvadori, Martina; Luigi Andreoli, Pier; Cipriani, Mattia; Consoli, Fabrizio; Cristofari, Giuseppe; De Angelis, Riccardo; di Giorgio, Giorgio; Giulietti, Danilo; Ingenito, Francesco; Gus'kov, Sergey Yu.; Rupasov, Alexander A.

    2018-01-01

    An experimental campaign to characterize the laser radiation absorption of foam targets and the subsequent emission of radiation from the produced plasma was carried out in the ABC facility of the ENEA Research Center in Frascati (Rome). Different targets have been used: plastic in solid or foam state and aluminum targets. The activated different diagnostics allowed to evaluate the plasma temperature, the density distribution, the fast particle spectrum and the yield of the X-Ray radiation emitted by the plasma for the different targets. These results confirm the foam homogenization action on laser-plasma interaction, mainly attributable to the volume absorption of the laser radiation propagating in such structured materials. These results were compared with simulation absorption models of the laser propagating into a foam target.

  6. A dynamic model of digestion and absorption in pigs

    DEFF Research Database (Denmark)

    Strathe, Anders Bjerring; Danfær, Allan Christian; Chwalibog, Andrzej

    2008-01-01

    The paper describes and evaluates the construction of a mathematical model to study the kinetics of digestion and absorption in growing pigs. The core of the model is based on a compartmental structure, which divides the gastro-intestinal tract into four anatomical segments: the stomach, two part......, starch, sugars and dietary fibre. Besides a chemical description of the feed, the model further requires information about daily dry matter intake and feeding frequency.......The paper describes and evaluates the construction of a mathematical model to study the kinetics of digestion and absorption in growing pigs. The core of the model is based on a compartmental structure, which divides the gastro-intestinal tract into four anatomical segments: the stomach, two parts...

  7. Sound absorption of microperforated panels inside compact acoustic enclosures

    Science.gov (United States)

    Yang, Cheng; Cheng, Li

    2016-01-01

    This paper investigates the sound absorption effect of microperforated panels (MPPs) in small-scale enclosures, an effort stemming from the recent interests in using MPPs for noise control in compact mechanical systems. Two typical MPP backing cavity configurations (an empty backing cavity and a honeycomb backing structure) are studied. Although both configurations provide basically the same sound absorption curves from standard impedance tube measurements, their in situ sound absorption properties, when placed inside a small enclosure, are drastically different. This phenomenon is explained using a simple system model based on modal analyses. It is shown that the accurate prediction of the in situ sound absorption of the MPPs inside compact acoustic enclosures requires meticulous consideration of the configuration of the backing cavity and its coupling with the enclosure in front. The MPP structure should be treated as part of the entire system, rather than an absorption boundary characterized by the surface impedance, calculated or measured in simple acoustic environment. Considering the spatial matching between the acoustic fields across the MPP, the possibility of attenuating particular enclosure resonances by partially covering the enclosure wall with a properly designed MPP structure is also demonstrated.

  8. Polarized absorption in determination of impurities in olive oil

    Science.gov (United States)

    Alias, A. N.; Zabidi, Z. M.; Yaacob, Y.; Amir, I. S.; Alshurdin, S. H. N.; Aini, N. A.

    2017-08-01

    The effect of impurities in olive oil blending with palm oil was characterized using polarized absorption method. Polarized absorption was based on the absorption of light which vibrating in a particular plane to pass through the sample. This polarized light allowed the molecule to absorb at the specific orientation. There were four samples have been prepared that were 100:0, 70:30, 50:50 and 0:100 with volume ratio of the olives to palm oil. Two linear polarizers were mounting between the samples in order to get linearly polarized. This specific orientation was affected the absorption spectra of the sample. The results have shown that the analyzing polarizer with angle 00 has bell shape spectra. All the orientation of analyzing polarizer had shown the maximum current output at 100% olive oil. Whereas 100% palm oil has shown the minimum current output. The changing in absorption spectra indicates that the anisotropic properties of each sample were different due to the present of impurities.

  9. Sound absorption property of openpore aluminum foams

    Directory of Open Access Journals (Sweden)

    WANG Fang

    2007-02-01

    Full Text Available This paper presents a study on sound absorption property of aluminum foam by evaluating its sound absorption coefficients using standing wave tube method. Experimental results showed that the average values of sound absorption coefficients (over the test frequency range are all above 0.4, which indicate very good sound absorption property of the aluminum foams. The sound absorption coefficient is affected by frequency and pore structure, and reaches its maximum value at around 1 000 Hz. With the increase of porosity and decrease of cell diameter, the sound absorption coefficient values increase.

  10. Absorption/desorption in sprays

    International Nuclear Information System (INIS)

    Naimpally, A.

    1987-01-01

    This survey paper shall seek to present the present state of knowledge concerning absorption and desorption in spray chambers. The first part of the paper presents the theories and formulas for the atomization and break-up of sprays in nozzles. Formulas for the average (sauter-mean) diameters are then presented. For the case of absorption processes, the formulas for the dimensionless mass transfer coefficients is in drops. The total; mass transfer is the total of the transfer in individual drops. For the case of desorption of sparingly soluble gases from liquids in a spray chamber, the mass transfer occurs in the spray just at the point of break-up of the jet. Formulas for the desorption of gases are presented

  11. Descriptive assessment for physical education

    OpenAIRE

    Pirih Tavčar, Ksenija

    2016-01-01

    Descriptive grading is a type of grading in which opinions about children’s knowledge or products are expressed in sentences. This opinion highlights what individual children know or have mastered, what they have not mastered, and what they should do to improve. In descriptive grading, the pupil’s work is assessed in terms of learning objectives. In their descriptive grades, physical education (PE) teachers write down everything that they have taught and reviewed with their pupils during t...

  12. Modernization of Atomic Absorption Spectrophotometer

    International Nuclear Information System (INIS)

    Tasic, Visa; Milivojevic, Dragan; Karabasevic, Dejan

    2003-01-01

    In Copper Institute in Bor, connection has been made between absorption spectrophotometer and standard PC with the aim to make its operation more reliable and comfortable. Applied solution includes both software and hardware components. An I/O interface module has been installed in PC [1]. Software component consists of programs for measuring and interpretation of results. Paper presents details of this job realization.(Author)

  13. Photodetector with enhanced light absorption

    Science.gov (United States)

    Kane, James

    1985-01-01

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  14. Iodine Absorption Cells Purity Testing

    Czech Academy of Sciences Publication Activity Database

    Hrabina, Jan; Zucco, M.; Philippe, Ch.; Pham, Minh Tuan; Holá, Miroslava; Acef, O.; Lazar, Josef; Číp, Ondřej

    2017-01-01

    Roč. 17, č. 1 (2017), s. 1-13, č. článku 17010102. ISSN 1424-8220 R&D Projects: GA ČR GA15-18430S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : iodine cells * absorption spectroscopy * laser spectroscopy * laser standards * frequency stability Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.677, year: 2016

  15. Olkiluoto biosphere description 2006

    International Nuclear Information System (INIS)

    Haapanen, R.; Aro, L.; Ilvesniemi, H.; Kareinen, T.; Kirkkala, T.; Mykrae, S.; Turkki, H.; Lahdenperae, A.-M.; Ikonen, A.T.K.

    2007-02-01

    This report summarises the current knowledge of the biosphere of Olkiluoto, and it is the first Biosphere Description Report. The elements considered were climate, topography, land use, overburden, terrestrial vegetation and fauna and sea flora, fauna and water. The principal aim was to present a synthesis of the present state (now to 2020) and the main features of past evolution of the biosphere at the site using currently available data. The lack of site specific parameters and their importance was discussed. Conceptual ecosystem models are presented for land and sea. Currently available data made it possible to calculate the biomass of the terrestrial vegetation and further convert it to carbon. In the case of terrestrial animals, preliminary figures are given for moose alone due to lack of sitespecific data. For the same reason, the sea ecosystem model was not quantified within this work. The ecosystems on Olkiluoto do not deviate from the surrounding areas. Since mires are few on Olkiluoto, forests are the most important land ecosystem. However, coastal areas are the transition zones between land and sea, and also potential sites for deep groundwater discharge. The major interest concerning aquatic ecosystems was laid on four future lakes potentially developing from the sea due to the land up-lift. Current sea sediments near Olkiluoto are future land areas, and thus very important. Spatially, the forest ecosystems of Olkiluoto are now most comprehensively covered, while the temporal coverage is highest in sea ecosystems. Lack of data is greatest in terrestrial fauna and sea sediments. During this work, the system boundaries were crossed and the use of data over disciplines was started. The data were mostly in agreement, but some discrepancies were detected. To solve these, and to supplement the existing data, some recommendations were given. (orig.)

  16. Remark on: the neutron spherical optical-model absorption.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A. B.; Nuclear Engineering Division

    2007-06-30

    The energy-dependent behavior of the absorption term of the spherical neutron optical potential for doubly magic {sup 208}Pb and the neighboring {sup 209}Bi is examined. These considerations suggest a phenomenological model that results in an intuitively attractive energy dependence of the imaginary potential that provides a good description of the observed neutron cross sections and that is qualitatively consistent with theoretical concepts. At the same time it provides an alternative to some of the arbitrary assumptions involved in many conventional optical-model interpretations reported in the literature and reduces the number of the parameters of the model.

  17. Study on Differential Optical Absorption Spectroscopy : Technique and its Applications

    OpenAIRE

    Liu, Jianguo

    2002-01-01

    ln the first part of speech, with a description of the principle of DOAS (Differential Optical Absorption Spectroscopy), the design and realization of two different kinds of DOAS systems are nresented. 0ne is using a slotted disc raoid scanning device with a photomultiplier, which is suitable for ambient air quality measurement. It can measure total 16 kinds of pollutants such as SO_2, NO, N02, NH_3, O_3, C_6H_6, C_7H_8 and CH_2O etc., with detection limits of 1-2ppb. The other is using a UV ...

  18. Characterization of heterotrophic nitrifying bacteria with respiratory ammonification and denitrification activity--description of Paenibacillus uliginis sp. nov., an inhabitant of fen peat soil and Paenibacillus purispatii sp. nov., isolated from a spacecraft assembly clean room.

    Science.gov (United States)

    Behrendt, Undine; Schumann, Peter; Stieglmeier, Michaela; Pukall, Rüdiger; Augustin, Jürgen; Spröer, Cathrin; Schwendner, Petra; Moissl-Eichinger, Christine; Ulrich, Andreas

    2010-10-01

    In the course of studying the influence of N-fertilization on N(2) and N(2)O flux rates in relation to soil bacterial community composition of a long-term fertilization experiment in fen peat grassland, a strain group was isolated that was related to a strain isolated from a spacecraft assembly clean room during diversity studies of microorganisms, which withstood cleaning and bioburden reduction strategies. Both the fen soil isolates and the clean room strain revealed versatile physiological capacities in N-transformation processes by performing heterotrophic nitrification, respiratory ammonification and denitrification activity. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the investigated isolates belonged to the genus Paenibacillus. Sequence similarities lower than 97% in comparison to established species indicated a separate species position. Except for the peptidoglycan type (A4alpha L-Lys-D-Asp), chemotaxonomic features of the isolates matched the genus description, but differences in several physiological characteristics separated them from related species and supported their novel species status. Despite a high 16S rRNA gene sequence similarity between the clean room isolate ES_MS17(T) and the representative fen soil isolate N3/975(T), DNA-DNA hybridization studies revealed genetic differences at the species level. These differences were substantiated by MALDI-TOF MS analysis, ribotyping and several distinct physiological characteristics. On the basis of these results, it was concluded that the fen soil isolates and the clean room isolate ES_MS17(T) represented two novel species for which the names Paenibacillus uliginis sp. nov. (type strain N3/975(T)=DSM 21861(T)=LMG 24790(T)) and Paenibacillus purispatii sp. nov. (type strain ES_MS17(T)=DSM 22991(T)=CIP 110057(T)) are proposed. Copyright © 2010 Elsevier GmbH. All rights reserved.

  19. Topical absorption and systemic toxicity.

    Science.gov (United States)

    Alikhan, Fatima Sasha; Maibach, Howard

    2011-09-01

    Dermal absorption of some chemicals and drugs can cause systemic toxicity. We evaluated several case reports from the past decade, which discuss the dermal absorption of a specific chemical and potential local and systemic effects. We focused on herbicide and pesticide exposure along with exposure to cutaneous medication, occupational contact, and cosmeceutical exposure. Although causality cannot be established in most cases, it is critical to be aware of the possible effects of topical absorption that may not be immediately apparent. We recommended further studies on specific chemicals to ascertain causality and determine the highest exposure level with no observed adverse affect level (NOAEL) and the reference dose (RfD). Post-marketing epidemiology data in most geographical areas are markedly limited. A weak link in public health resides in the inadequate reporting and workup of alleged chemically related adverse effects. This arena mandates a re-thinking of how to increase this reporting, and workup, as a backup to our preclinical and clinical studies. Public awareness and funding will be rewarded by increased evidence to backup pre-approval pre-marketing studies.

  20. Organizational forms and knowledge absorption

    Directory of Open Access Journals (Sweden)

    Radovanović Nikola

    2016-01-01

    Full Text Available Managing the entire portion of knowledge in an organization is a challenging task. At the organizational level, there can be enormous quantities of unknown, poorly valued or inefficiently applied knowledge. This is normally followed with the underdeveloped potential or inability of organizations to absorb knowledge from external sources. Facilitation of the efficient internal flow of knowledge within the established communication network may positively affect organizational capacity to absorb or identify, share and subsequently apply knowledge to commercial ends. Based on the evidences that the adoption of different organizational forms affects knowledge flows within an organization, this research analyzed the relationship between common organizational forms and absorptive capacity of organizations. In this paper, we test the hypothesis stating that the organizational structure affects knowledge absorption and exploitation in the organization. The methodology included quantitative and qualitative research method based on a questionnaire, while the data has been statistically analyzed and the hypothesis has been tested with the use of cross-tabulation and chi-square tests. The findings suggest that the type of organizational form affects knowledge absorption capacity and that having a less formalized and more flexible structure in an organization increases absorbing and exploiting opportunities of potentially valuable knowledge.

  1. Trusting Description: Authenticity, Accountability, and Archival Description Standards

    Science.gov (United States)

    MacNeil, Heather

    2009-01-01

    It has been suggested that one of the purposes of archival description is to establish grounds for presuming the authenticity of the records being described. The article examines the implications of this statement by examining the relationship between and among authenticity, archival description, and archival accountability, assessing how this…

  2. Microwave absorption properties of gold nanoparticle doped polymers

    DEFF Research Database (Denmark)

    Jiang, Chenhui; Ouattara, Lassana; Ingrosso, Chiara

    2011-01-01

    This paper presents a method for characterizing microwave absorption properties of gold nanoparticle doped polymers. The method is based on on-wafer measurements at the frequencies from 0.5GHz to 20GHz. The on-wafer measurement method makes it possible to characterize electromagnetic (EM) property...... of small volume samples. The epoxy based SU8 polymer and SU8 doped with gold nanoparticles are chosen as the samples under test. Two types of microwave test devices are designed for exciting the samples through electrical coupling and magnetic coupling, respectively. Measurement results demonstrate...... that the nanocomposites absorb a certain amount of microwave energy due to gold nanoparticles. Higher nanoparticle concentration results in more significant absorption effect....

  3. Caracterização Estrutural e da Capacidade de Absorção de Água em Bloco de Cimento com Adição de Resíduo de Pneu (Ecobloco = Water Absorption Capacity and Structural Characterization of Cement Block with Addition of Tire Residue (Ecobloco.

    Directory of Open Access Journals (Sweden)

    Maria da Conceição S. Gomes

    2007-12-01

    Full Text Available Foram feitos caracterizações estruturais com ensaios em corpo de prova, medidas granulométricas do resíduo, docimento, do pó de brita e da areia, e a medida da capacidade de absorção de água em blocos de cimento (chamados de ecoblocos com adição de 5%, 10%, 15%, 25% e 35% de resíduo de pneu, obtido por meio de raspagem de pneus automotivos inservíveis. A geometria de confecção dos ecoblocos foi projetada para serem encaixados no empilhamento vertical, requerendo o mínimo de massa de cimento para a confecção de parede de vedação. = Experiment for structural characterizations were made in test body as well as measurements of the capacity of water absorption in cement blocks (called ecoblocos with the addition of 5%, 10%, 15%, 25% and 35% of tire residue.These additions are obtained by means of worn out tire’s scratching. The ecoblocos´ design was projected for them to be inserted in the vertical piling up, requesting the minimum of mortar for the construction of walls.

  4. Characteristics of water absorption of beans

    OpenAIRE

    上中, 登紀子; 森, 孝夫; 豊沢, 功; Tokiko, Uenaka; Takao, Mori; Isao, Toyosawa

    2001-01-01

    Characteristics of water absorption of soybean, azuki bean and kidney beans (cv. Toramame and Taishokintoki) were investigated. The way of water absorption of soybean was different from that of other beans, because soybeans absorbed water from whole surface of seed coat immediately after the immersion. Azuki beans absorbed extremely slowly water from only strophiole, and then the water absorption in other tissue was induced by a certain amount of water absorption playing a role of trigger. Th...

  5. Evolution of absorption machines; Evolution des machines a absorption

    Energy Technology Data Exchange (ETDEWEB)

    Soide, I.; Klemsdal, E. [Gaz de France (GDF), 75 - Paris (France); Le Goff, P.; Hornut, J.M. [LSGC-ENSIC, 54 - Nancy (France)

    1997-12-31

    Most of todays absorption air-conditioning machineries use the lithium bromide-water pair. The most performing can operate at a 150-160 deg. C, the temperature being limited by the corrosion resistance of metals with respect to LiBr solutions. Also, there is a revival of interest for water-ammonia systems. These systems require the use of a rectification column which reduces the coefficient of performance. Higher thermal performances are reached with hydrocarbon pairs and ternary mixtures (water-methanol-LiBr etc..). This paper presents different schemes of refrigerating heat pumps based on these different systems. (J.S.)

  6. Uniform semiclassical approximation for absorptive scattering systems

    International Nuclear Information System (INIS)

    Hussein, M.S.; Pato, M.P.

    1987-07-01

    The uniform semiclassical approximation of the elastic scattering amplitude is generalized to absorptive systems. An integral equation is derived which connects the absorption modified amplitude to the absorption free one. Division of the amplitude into a diffractive and refractive components is then made possible. (Author) [pt

  7. Structural sound absorption in liquid metals

    International Nuclear Information System (INIS)

    Niyazov, S.

    1993-01-01

    Present article is devoted to structural sound absorption in liquid metals. The study of sound absorption in liquid metals shown that in all studied objects the structural absorption of sound was observed. The mechanism of structural relaxation in molten metal was revealed.

  8. Iron absorption in relation to iron status

    International Nuclear Information System (INIS)

    Magnusson, B.; Bjoern-Rasmussen, E.; Hallberg, L.; Rossander, L.

    1981-01-01

    The absorption from a 3 mg dose of ferrous iron was measured in 250 male subjects. The absorption was related to the log concentration of serum ferritin in 186 subjects of whom 99 were regular blood donors (r= -0.76), and to bone marrow haemosiderin grading in 52 subjects with varying iron status. The purpose was to try and establish a percentage absorption from such a dose that is representative of subjects who are borderline iron deficient. This information is necessary for food iron absorption studies in order (1) to calculate the absorption of iron from the diet at a given iron status and (2) compare the absorption of iron from different meals studied in different groups of subjects by different investigarors. The results suggest that an absorption of about 40% of a 3 mg reference dose of ferrous iron is given in a fasting state, roughly corresponds to the absorption in borderline-iron-deficient subjects. The results indicate that this 40% absorption value corresponds to a serum ferritin level of 30 μg/l and that food iron absorption in a group of subjects should be expressed preferably as the absorption corresponding to a reference-dose absorption of 45%, or possibly a serum ferritin level of 30 μg/l. (author)

  9. Quantum trajectory description of entanglement dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Guevara, Ivonne [Departamento de Fisica, Universidad Nacional de Colombia, Carrera 30 No.45-03, Bogota D.C. (Colombia); Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111 (Australia); Viviescas, Carlos [Departamento de Fisica, Universidad Nacional de Colombia, Carrera 30 No.45-03, Bogota D.C. (Colombia)

    2013-07-01

    We present and overview of the characterization of the dynamical evolution of entanglement in open quantum system by means of diffusive quantum trajectories. We show how this method allows for a complete description of this phenomenon providing deterministic evolution equations for some experimentally relevant cases, and excellent upper bounds for the entanglement dynamics in some other cases. Remarkably, for a family of entanglement measures, all the information of the entanglement dynamics can be recovered from a single trajectory. For some of the cases considered we propose quantum optical experimental setups which allow for a real time measurement of the entanglement time evolution.

  10. Indoor Measurement of Angle Resolved Light Absorption by Black Silicon

    DEFF Research Database (Denmark)

    Amdemeskel, Mekbib Wubishet; Iandolo, Beniamino; Davidsen, Rasmus Schmidt

    2017-01-01

    Angle resolved optical spectroscopy of photovoltaic (PV) samples gives crucial information on PV panels under realistic working conditions. Here, we introduce measurements of angle resolved light absorption by PV cells, performed indoors using a collimated high radiance broadband light source. Our...... indoor method offers a significant simplification as compared to measurements by solar trackers. As a proof-of-concept demonstration, we show characterization of black silicon solar cells. The experimental results showed stable and reliable optical responses that makes our setup suitable for indoor......, angle resolved characterization of solar cells....

  11. [The percutaneous absorption of diclofenac].

    Science.gov (United States)

    Riess, W; Schmid, K; Botta, L; Kobayashi, K; Moppert, J; Schneider, W; Sioufi, A; Strusberg, A; Tomasi, M

    1986-07-01

    The percutaneous absorption of diclofenac diethylammonium 1.16% (w/w) in a combination of emulsion cream and gel (Voltaren Emulgel) and of diclofenac sodium 1% (w/w) in a cream formulation (Voltaren cream) was investigated in guinea-pig, rabbit and man. The percutaneous absorption of diclofenac sodium in guinea-pig was 3 to 6% of the dose when the cream formulation in doses of 320, 100 or 40 mg was applied on 10 cm2 of occluded skin and left in place for 6 h. The transdermal delivery of 14C-labelled diclofenac yielded plateau plasma concentrations of radiotracer from 1.5 h after application until removal of the residual cream. Subsequently the steady state drug depots in the skin and muscle tissue were depleted promptly. During daily administration the steady state levels in the muscle tissue in proximity to the application site were about 3 times higher than in distant muscle tissue. By topical application on knee joints of rabbits diclofenac penetrated into the patellar ligament, the adipose corpus and the synovial fluid. In man the percutaneous absorption was 6% of the dose when the Emulgel formulation was spread by 5 mg/cm2 and left for 12 h on non-occluded skin. The pattern of metabolites of diclofenac in human urine was the same after topical and oral administration. In man, upon daily topical administration of 3 times 2.5 g cream formulation (10 mg/cm2) the diclofenac steady state plasma levels were 20 to 40 nmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Reproducibility of The Random Incidence Absorption Coefficient Converted From the Sabine Absorption Coefficient

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho; Chang, Ji-ho

    2015-01-01

    Absorption coefficients measured in reverberation chambers, Sabine absorption coefficients, suffer from two major problems. Firstly, they sometimes exceed unity. Secondly, the reproducibility of the Sabine absorption coefficients is quite poor, meaning that the Sabine absorption coefficients vary...... resistivity optimization outperforms the surface impedance optimization in terms of the reproducibility....

  13. Phytases for Improved Iron Absorption

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Nyffenegger, Christian; Meyer, Anne S.

    2014-01-01

    Microbial phytases (EC 3.1.3.8) catalyse dephosphorylation of phytic acid, which is the primary storage compound for phosphorous in cereal kernels. The negatively charged phosphates in phytic acid chelate iron (Fe3+) and thus retards iron bioavailability in humans 1. Supplementation of microbial...... phytase can improve iron absorption from cereal-based diets 2. In order for phytase to catalyse iron release in vivo the phytase must be robust to low pH and proteolysis in the gastric ventricle. Our work has compared the robustness of five different microbial phytases, evaluating thermal stability...

  14. Electronic absorption spectra of antiviral aminophenol derivatives

    Science.gov (United States)

    Belkov, M. V.; Ksendzova, G. A.; Raichyonok, T. F.; Skornyakov, I. V.; Sorokin, V. L.; Tolstorozhev, G. B.; Shadyro, O. I.

    2011-03-01

    Electronic absorption spectra of aminophenol derivatives in solutions have been studied. A general property of the absorption spectra of these compounds, the dependence of the maximum of a long-wavelength absorption band on the solvent polarity, is revealed. As a rule, the absorption band maximum of compounds possessing pharmacological properties shows a greater shift to short wavelength with an increase in the medium polarity than that of inactive compounds. Absorption measurements of solutions of aminophenol derivatives can be used for a tentative estimation of their antiviral activity.

  15. X-ray spectroscopic characterization of laser produced hot dense plasmas; Caracterisation par spectroscopie X de plasmas chauds et denses crees par lasers de puissance

    Energy Technology Data Exchange (ETDEWEB)

    Kontogiannopoulos, N

    2007-12-15

    In this work we performed experiments of emission and absorption spectroscopy of laser produced plasmas, to provide well characterized spectral data which permit to benchmark atomic physics codes. More precisely, we produced xenon and krypton plasmas in NLTE (non local thermodynamic equilibrium) conditions and studied their emission spectra. In a second experiment, we characterized the absorption spectra of zinc sulfide and aluminium plasmas in LTE (local thermodynamic equilibrium) conditions.The first two chapters give an outline of the theory involved in the study of the emission and absorption plasma spectroscopy. Chapter 1 describes the different atomic processes occurring in a plasma. The LTE and the NLTE statistics ruling the equilibrium of the atomic processes are presented. Then, we give a brief description of the different codes of plasma atomic physics used in the analysis of our experimental data, namely HULLAC, SCO and TRANSPEC/AVERROES. In Chapter 2 the macroscopic theory of the radiation transport through a plasma is given. We describe also the self-similar model of Basko and the view factor approach, which permits us to calculate the heating conditions of the absorption foils achieved in the interior of the spherical gold cavity. Chapter 3 gives a description of the instruments used for realizing the two experiments, as well as the technical characteristics of the LULI2000 laser facility used to perform the experiments. Chapter 4 presents the experiment realized to characterize the emission spectra of the xenon and krypton plasmas in NLTE, as well the analysis of the experimental data with TRANSPEC/AVERROES. Finally, the experiment for measuring the absorption spectrum of the ZnS plasma mixture and the analysis of the experimental data with the code SCO are given in Chapter 5.

  16. Modelling object typicality in description logics - [Workshop on Description Logics

    CSIR Research Space (South Africa)

    Britz, K

    2009-07-01

    Full Text Available The authors presents a semantic model of typicality of concept members in description logics that accords well with a binary, globalist cognitive model of class membership and typicality. The authors define a general preferential semantic framework...

  17. The exact electromagnetic field description of photon emission, absorption, and radiation pattern. II.

    Science.gov (United States)

    Grimes, Dale M; Grimes, Craig A

    2002-10-01

    This is the second of two articles, the first of which contains a proposed explanation of quantum theory based upon electron nonlocality and classical electrodynamics. In this second article classical field theory is used to describe a unique field set for exchange of radiation between an atomic eigenstate and the far field. The radiation satisfies the thermodynamic condition of reversibility as described by Boltzmann, Planck, and Einstein. The exchanged radiation supports the kinematic properties of photons, and it can be emitted or absorbed by a vanishingly small volume.

  18. Iodine Absorption Cells Purity Testing

    Directory of Open Access Journals (Sweden)

    Jan Hrabina

    2017-01-01

    Full Text Available This article deals with the evaluation of the chemical purity of iodine-filled absorption cells and the optical frequency references used for the frequency locking of laser standards. We summarize the recent trends and progress in absorption cell technology and we focus on methods for iodine cell purity testing. We compare two independent experimental systems based on the laser-induced fluorescence method, showing an improvement of measurement uncertainty by introducing a compensation system reducing unwanted influences. We show the advantages of this technique, which is relatively simple and does not require extensive hardware equipment. As an alternative to the traditionally used methods we propose an approach of hyperfine transitions’ spectral linewidth measurement. The key characteristic of this method is demonstrated on a set of testing iodine cells. The relationship between laser-induced fluorescence and transition linewidth methods will be presented as well as a summary of the advantages and disadvantages of the proposed technique (in comparison with traditional measurement approaches.

  19. Enhancing THz Absorption using Thin-Film Multilayer Stacks

    Science.gov (United States)

    Grbovic, Dragoslav; Bolakis, Christos; Karunasiri, Gamani

    2010-03-01

    Terahertz imaging has seen significant proliferation in recent years. This band of electromagnetic spectrum has been underutilized for a long time due to the lack of sufficiently powerful sources and sensitive detectors. Because of virtually harmless effects on living tissue, terahertz (THz) radiation is attractive for various applications, ranging from non-invasive medical diagnostics to detection of concealed weapons. Our work focuses on identifying materials, or more specifically a stack of thin-films with increased absorption in the band of interest. In this work, we demonstrate a method that combines finite element modeling, thin-film deposition and experimental characterization to create highly-absorptive multi-layer stacks. Finite element modeling is used to simulate the absorption of a combination of thin dielectric and metallic films. Metals are deposited using e-beam evaporation and dielectric films using plasma enhanced chemical vapor deposition (PECVD). The simulated and measured THz absorption characteristics of the composite thin-film multilayer stacts will be presented.

  20. Solute dispersion in open channel flow with bed absorption

    Science.gov (United States)

    Wang, Ping; Chen, G. Q.

    2016-12-01

    Reactive solute dispersion is of essential significance in various ecological and environmental applications. It is only qualitatively known that boundary absorption depletes pollutant around the boundary and reduces the concentration nearby. All the existing studies on this topic have been focused on the longitudinally distributed mean concentration, far from enough to fully characterize the transport process with tremendous cross-sectional concentration nonuniformity. This work presents an analytical study of the evolution of two-dimensional concentration distribution for solute dispersion in a laminar open channel flow with bed absorption. The fourth order Aris-Gill expansion proposed in our previous study (Wang and Chen, 2016b) is further extended for the case with bed absorption to cover the transitional effects of skewness and kurtosis. Results reveal the extremely nonuniform cross-sectional concentration distribution, and demonstrate that concentration at the bed instead of the mean should be used for reliable quantification of the absorption flux. The accurate two-dimensional concentration distribution presented in this study brings important environmental implications such as risk assessment associated with peak concentration position and duration of toxic pollutant cloud in open channel waters.

  1. Sub-millimetre wave absorption spectra of artificial RNA molecules

    CERN Document Server

    Globus, T; Woolard, D; Gelmont, B

    2003-01-01

    We demonstrate submillimetre-wave Fourier transform spectroscopy as a novel technique for biological molecule characterization. Transmission measurements are reported at frequencies 10-25 cm sup - sup 1 for single- and double-stranded RNA molecules of known base-pair sequences: homopolymers poly[A], poly[U], poly[C] and poly[G], and double-stranded homopolymers poly[A]-poly[U] and poly[C]-poly[G]. Multiple resonances are observed (i.e. in the microwave through terahertz frequency regime). We also present a computational method to predict the low-frequency absorption spectra of short artificial DNA and RNA. Theoretical conformational analysis of molecules was utilized to derive the low-frequency vibrational modes. Oscillator strengths were calculated for all the vibrational modes in order to evaluate their weight in the absorption spectrum of a molecule. Normal modes and absorption spectra of the double-stranded RNA chain poly[C]-poly[G] were calculated. The absorption spectra extracted from the experiment wer...

  2. Terahertz sensing of highly absorptive water-methanol mixtures with multiple resonances in metamaterials.

    Science.gov (United States)

    Chen, Min; Singh, Leena; Xu, Ningning; Singh, Ranjan; Zhang, Weili; Xie, Lijuan

    2017-06-26

    Terahertz sensing of highly absorptive aqueous solutions remains challenging due to strong absorption of water in the terahertz regime. Here, we experimentally demonstrate a cost-effective metamaterial-based sensor integrated with terahertz time-domain spectroscopy for highly absorptive water-methanol mixture sensing. This metamaterial has simple asymmetric wire structures that support multiple resonances including a fundamental Fano resonance and higher order dipolar resonance in the terahertz regime. Both the resonance modes have strong intensity in the transmission spectra which we exploit for detection of the highly absorptive water-methanol mixtures. The experimentally characterized sensitivities of the Fano and dipole resonances for the water-methanol mixtures are found to be 160 and 305 GHz/RIU, respectively. This method provides a robust route for metamaterial-assisted terahertz sensing of highly absorptive chemical and biochemical materials with multiple resonances and high accuracy.

  3. Optical absorption of tetraphenylporphyrin thin films in UV-vis-NIR region.

    Science.gov (United States)

    El-Nahass, M M; Zeyada, H M; Aziz, M S; Makhlouf, M M

    2005-11-01

    The optical absorption of thermally evaporated tetraphenylporphyrin (TPP) in the UV-vis-NIR region have been studied. The absorption spectra recorded in the UV-vis region for the as deposited and annealed films showed different absorption bands, namely the Soret(B) at region 360-490nm, Q-band region consist of four bands in the region 500-720nm and two other bands labeled N and M in UV region. The Soret band always shows its characteristic effect splitting in all the TPP thin films and the effect of annealing on the intensities of these components have been observed. The spectra of the infrared absorption allow characterization of vibrational modes for the powder, as deposited and annealed thin films. Some of the optical absorption parameters, namely molar extinction coefficient, epsilon, half band width, Deltalambda, electronic dipole strength, q(2) and oscillator strength, f, of the principle optical transitions have also been evaluated.

  4. Nonlinear Optical Absorption and Refraction Study of Metallophthalocyanine Dyes.

    Science.gov (United States)

    Wei, Tai-Huei

    Metallophthalocyanines and related conjugated ring molecules have attracted recent interest because, as confined, reduced-dimensionality (2D) delocalized electronic systems, large electronic nonlinearities are expected. This has led to interest in: (1) developing a fundamental understanding of the mechanisms which contribute to the nonlinear optical response, (2) obtaining well defined and accurate measurements of the refractive and absorptive contributions to the observed nonlinearities, and (3) identifying means of enhancing and maximizing the nonlinear susceptibilities. This dissertation deals with the characterization of the nonlinear absorption and refraction of two representative metallophthalocyanine dyes: chloro aluminum phthalocyanine dissolved in methanol, referred to as CAP, and a silicon naphthalocyanine derivative dissolved in toluene, referred to as SiNc. Using the Z -scan technique, the experiments are performed on both the picosecond and nanosecond timescales at a wavelength of 0.532 mum. The Z-scan technique separates nonlinear absorption and nonlinear refraction by measuring both the total transmittance and far field axial transmittance of a focused Gaussian beam as a function of the position (z) of the material relative to the beam waist. In the picosecond regime, Z-scan experiments using pulses of different widths indicate that both nonlinear absorption and refraction are fluence dependent. Therefore, we determine the dominant nonlinearities are excited state absorption (ESA) and excited state refraction (ESR). Through nanosecond Z-scan measurements, we see additional nonlinear absorption and nonlinear refraction. By power limiting measurements using single picosecond pulses and trains of picosecond pulses separated by 7 nanosecond, this additional nonlinear absorption is determined due to intersystem crossing to the triplet state with subsequent triplet state ESA. Therefore, a five state model is used to explain the nonlinear absorption. On the

  5. Detector Description Framework in LHCb

    CERN Document Server

    Ponce, Sébastien

    2003-01-01

    The Gaudi architecture and framework are designed to provide a common infrastructure and environment for simulation, filtering, reconstruction and analysis applications. In this context, a Detector Description Service was developed in LHCb in order to also provide easy and coherent access to the description of the experimental apparatus. This service centralizes every information about the detector, including geometry, materials, alignment, calibration, structure and controls. From the proof of concept given by the first functional implementation of this service late 2000, the Detector Description Service has grown and has become one of the major components of the LHCb software, shared among all applications, including simulation, reconstruction, analysis and visualization. We describe here the full and functional implementation of the service. We stress the easiness of customization and extension of the detector description by the user, on the seamless integration with condition databases in order to handle ...

  6. Absorption of Sunlight by Water Vapor in Cloudy Conditions: A Partial Explanation for the Cloud Absorption Anomaly

    Science.gov (United States)

    Crisp, D.

    1997-01-01

    The atmospheric radiative transfer algorithms used in most global general circulation models underestimate the globally-averaged solar energy absorbed by cloudy atmospheres by up to 25 W/sq m. The origin of this anomalous absorption is not yet known, but it has been attributed to a variety of sources including oversimplified or missing physical processes in these models, uncertainties in the input data, and even measurement errors. Here, a sophisticated atmospheric radiative transfer model was used to provide a more comprehensive description of the physical processes that contribute to the absorption of solar radiation by the Earth's atmosphere. We found that the amount of sunlight absorbed by a cloudy atmosphere is inversely proportional to the solar zenith angle and the cloud top height, and directly proportional to the cloud optical depth and the water vapor concentration within the clouds. Atmospheres with saturated, optically-thick, low clouds absorbed about 12 W/sq m more than clear atmospheres. This accounts for about 1/2 to 1/3 of the anomalous ab- sorption. Atmospheres with optically thick middle and high clouds usually absorb less than clear atmospheres. Because water vapor is concentrated within and below the cloud tops, this absorber is most effective at small solar zenith angles. An additional absorber that is distributed at or above the cloud tops is needed to produce the amplitude and zenith angle dependence of the observed anomalous absorption.

  7. HI Absorption in Merger Remnants

    Science.gov (United States)

    Teng, Stacy H.; Veileux, Sylvain; Baker, Andrew J.

    2012-01-01

    It has been proposed that ultraluminous infrared galaxies (ULIRGs) pass through a luminous starburst phase, followed by a dust-enshrouded AGN phase, and finally evolve into optically bright "naked" quasars once they shed their gas/dust reservoirs through powerful wind events. We present the results of our recent 21- cm HI survey of 21 merger remnants with the Green Bank Telescope. These remnants were selected from the QUEST (Quasar/ULIRG Evolution Study) sample of ULIRGs and PG quasars; our targets are all bolometrically dominated by AGN and sample all phases of the proposed ULIRG -> IR-excess quasar -> optical quasar sequence. We explore whether there is an evolutionary connection between ULIRGs and quasars by looking for the occurrence of HI absorption tracing neutral gas outflows; our results will allow us to identify where along the sequence the majority of a merger's gas reservoir is expelled.

  8. Sound absorption with green materials

    Science.gov (United States)

    Trematerra, Amelia; Lombardi, Ilaria

    2017-07-01

    Green materials are a valid alternative to traditional materials that are by-products of processing oil. At the end of their useful life, green materials can be disposed of without polluting the environment. They are now being used in the construction and automotive industries. While, studies are currently being carried out in the aviation sector on the use of green materials for non-structural components of airplanes. Green materials can be used to improve the acoustic comfort inside buildings as well as mitigate reverberation, echoes effects and reduce the transmission of noise between rooms. In this paper, the acoustic measurements of the properties of green materials are reported. The absorption coefficient of samples of the materials were measured in the frequency range from 200 Hz to 2,000 Hz with an impedance tube, with the flow resistance being measured.

  9. Phosphorus absorption in drip irrigation

    International Nuclear Information System (INIS)

    Guennelon, R.; Habib, R.

    1979-01-01

    Introducing the use of solute phosphate with drip irrigation may be an unsatisfying practice on account of the very weak mobility of PO 4 anion. Nevertheless P can move down to 30-40 cm depth by following the saturated flux along earth-worms holes or crakes, or by displacement in very narrow structural porosity, even in heavy soils. In this case roots cannot easily absorb PO 4 from soil solution, as soon as the soil is quite saturated. On the other hand, it seems that P absorption occurs very quickly and easily when the implantation of 32 P tagged solution is carried out at the border of zone which is concerned by the irrigation effects [fr

  10. Infrared absorption spectroscopic study of Nd 3+ substituted Zn–Mg ...

    Indian Academy of Sciences (India)

    Compositions of polycrystalline ZnMg1-Fe2–NdO4 ( = 0.00, 0.20, 0.40, 0.60, 0.80 and 1.00; = 0.00, 0.05 and 0.10) ferrites were prepared by standard ceramic method and characterized by X-ray diffraction, scanning electron microscopy and infrared absorption spectroscopy. Far infrared absorption spectra show ...

  11. Infrared absorption spectroscopic study of Nd 3 substituted Zn–Mg ...

    Indian Academy of Sciences (India)

    Compositions of polycrystalline ZnMg1-Fe2–NdO4 ( = 0.00, 0.20, 0.40, 0.60, 0.80 and 1.00; = 0.00, 0.05 and 0.10) ferrites were prepared by standard ceramic method and characterized by X-ray diffraction, scanning electron microscopy and infrared absorption spectroscopy. Far infrared absorption spectra show ...

  12. Heating of solar coronal loops by resonant absorption of Alfven waves

    Science.gov (United States)

    Grossmann, William; Smith, Robert A.

    1988-01-01

    Numerical calculations governing the efficiency of coronal loop heating by the resonant absorption of shear Alfven waves are reported. The loop structure is modeled by a class of axisymmetric force-free equilibria of a long straight cylinder, approximating a large aspect ratio loop. For a range of parameters characterizing the evolution of solar coronal loops, the absorption bandwidth falls in the frequency range of the photospheric motions due to granulation and p-modes. Resonant Alfven wave absorption is thus a viable mechanism for coronal loop heating.

  13. The Effects of Various Additive Components on the Sound Absorption Performances of Polyurethane Foams

    Directory of Open Access Journals (Sweden)

    Shuming Chen

    2015-01-01

    Full Text Available Flexible polyurethane (PU foams comprising various additive components were synthesized to improve their acoustic performances. The purpose of this study was to investigate the effects of various additive components of the PU foams on the resultant sound absorption, which was characterized by the impedance tube technique to obtain the incident sound absorption coefficient and transmission loss. The maximum enhancement in the acoustic properties of the foams was obtained by adding fluorine-dichloroethane (141b and triethanolamine. The results showed that the acoustic absorption properties of the PU foams were improved by adding 141b and triethanolamine and depended on the amount of the water, 141b, and triethanolamine.

  14. Comparative study of sound absorption coefficient determination using FEM method and experimental tests on Kundt's tube

    Science.gov (United States)

    Deaconu, Marius; Toma, Adina Cristina; Dragasanu, Luminita Ioana; Mihai, Dragos

    2017-06-01

    Sound absorption coefficient is a commonly used parameter to characterize the acoustic properties of sound absorbing materials that plays an important role in noise attenuation. For this study a specific material has been chosen in order to be evaluated experimentally and compared with the simulated results. Both simulation and experimental assessments used to estimate the sound absorption coefficient are based on transfer function method in accordance with standard SR EN JSO 10354-2. Results are obtained for 15, 30, 45 mm material sample thickness in order to assess the relationship between absorption coefficient, thickness and frequency response. Comparative analysis is performed to determine differences given by the two approaches.

  15. Broken-cloud enhancement of solar radiation absorption

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, R.N. [Science Applications International Corporation, San Diego, CA (United States); Somerville, R.C. [Univ. of California, La Jolla, CA (United States); Subasilar, B. [Curtain Univ. of Technology, Perth (Australia)

    1996-04-01

    Two papers recently published in Science have shown that there is more absorption of solar radiation than estimated by current atmospheric general circulation models (GCMs) and that the discrepancy is associated with cloudy scenes. We have devised a simple model which explains this as an artifact of stochastic radiative transport. We first give a heuristic description, unencumbered by mathematical detail. Consider a simple case with clouds distributed at random within a single level whose upper and lower boundaries are fixed. The solar zenith angle is small to moderate; this is therefore an energetically important case. Fix the average areal liquid water content of the cloud layer, and take the statistics of the cloud distribution to be homogeneous within the layer. Furthermore, assume that all the clouds in the layer have the same liquid water content, constant throughout the cloud, and that apart from their droplet content they are identical to the surrounding clear sky. Let the clouds occupy on the average a fraction p{sub cld} of the volume of the cloudy layer, and let them have a prescribed distribution of sizes about some mean. This is not a fractal distribution, because it has a scale. Cloud shape is unimportant so long as cloud aspect ratios are not far from unity. Take the single-scattering albedo to be unity for the droplets in the clouds. All of the absorption is due to atmospheric gases, so the absorption coefficient at a point is the same for cloud and clear sky. Absorption by droplets is less than 10% effect in the numerical stochastic radiation calculations described below, so it is reasonable to neglect it at this level of idealization.

  16. Impact of transporters in oral absorption

    DEFF Research Database (Denmark)

    Gram, Luise Kvisgaard; Rist, Gerda Marie; Steffansen, Bente

    2009-01-01

    was to investigate whether transporters were involved in the intestinal absorption of an organic anion A275 and to compare the impact of interactions related to transporters in the Caco-2 cell model versus the in vivo rat model of intestinal absorption. In both models, it was investigated whether intestinal...... permeation of A275 was concentration dependent and affected by inhibitors or competitive organic anions. Interactions related to transporters in intestinal permeation was clearly demonstrated in the Caco-2 cell model but was not directly evident for in vivo rat absorption. However, an observed biphasic...... in vivo absorption and a large intervariability between rats might mask a dose-dependent absorption of A275. To avoid these suggested interactions, a dose of at least 10 mg/kg, which saturates the intestinal transporters involved in A275 absorption, should be administered, but at doses below that the risk...

  17. Phytosterol glycosides reduce cholesterol absorption in humans

    OpenAIRE

    Lin, Xiaobo; Ma, Lina; Racette, Susan B.; Anderson Spearie, Catherine L.; Ostlund, Richard E.

    2009-01-01

    Dietary phytosterols inhibit intestinal cholesterol absorption and regulate whole body cholesterol excretion and balance. However, they are biochemically heterogeneous and a portion is glycosylated in some foods with unknown effects on biological activity. We tested the hypothesis that phytosterol glycosides reduce cholesterol absorption in humans. Phytosterol glycosides were extracted and purified from soy lecithin in a novel two-step process. Cholesterol absorption was measured in a series ...

  18. Vitamin B12 absorption from eggs.

    Science.gov (United States)

    Doscherholmen, A; McMahon, J; Ripley, D

    1975-09-01

    The assimilation of 57Co B12 from in vivo labeled eggs was much inferior to that of a comparable amount of crystalline 57Co B12. Furthermore, the absorption varied with the form in which the eggs were served. Judged by the urinary excretion test and the plasma absorption of radioactivity the average absorption from boiled and fried eggs was more than twice that from scrambled whole eggs, but less than half that absorbed from crystalline 57Co B12.

  19. Flame emission, atomic absorption and fluorescence spectrometry

    International Nuclear Information System (INIS)

    Horlick, G.

    1980-01-01

    Six hundred and thirty references are cited in this review. The information in the review is divided into 12 major areas: books, reviews, and bibliographies; fundamental studies in flames; developments in instrumentation; measurement techniques and procedure; flame emission spectrometry; flame atomic absorption spectrometry; flame molecular absorption spectrometry; electrothermal atomization atomic absorption spectroscopy; hydride generation techniques; graphite furnace atomic emission spectrometry; atomic fluorescence spectrometry; and analytical comparisons

  20. A descriptive epidemiological study on stroke in Kampala, Uganda ...

    African Journals Online (AJOL)

    Background Basic stroke features are hardly known in sub-Saharan countries, and no data are available in Uganda. Objective To characterize patients presenting with clinical stroke to Mulago Hospital. Design Descriptive epidemiological study. Setting Mulago National referral Hospital in Kampala, Uganda. Participants ...

  1. The genus Xiphinema in southern Africa. XI. Description of ...

    African Journals Online (AJOL)

    The genus Xiphinema in southern Africa. XI. Description of Xiphinema stockeri n. sp. from. Botswana (Nematoda: Dorylaimida). J.C. de W. Kruger and J. Heyns. Department of Zoology, Rand Afrikaans University, Johannesburg. Xiphinema stockeri n. sp. is described from Botswana The new species is characterized by an ...

  2. NMR imaging of cell phone radiation absorption in brain tissue

    Science.gov (United States)

    Gultekin, David H.; Moeller, Lothar

    2013-01-01

    A method is described for measuring absorbed electromagnetic energy radiated from cell phone antennae into ex vivo brain tissue. NMR images the 3D thermal dynamics inside ex vivo bovine brain tissue and equivalent gel under exposure to power and irradiation time-varying radio frequency (RF) fields. The absorbed RF energy in brain tissue converts into Joule heat and affects the nuclear magnetic shielding and the Larmor precession. The resultant temperature increase is measured by the resonance frequency shift of hydrogen protons in brain tissue. This proposed application of NMR thermometry offers sufficient spatial and temporal resolution to characterize the hot spots from absorbed cell phone radiation in aqueous media and biological tissues. Specific absorption rate measurements averaged over 1 mg and 10 s in the brain tissue cover the total absorption volume. Reference measurements with fiber optic temperature sensors confirm the accuracy of the NMR thermometry. PMID:23248293

  3. Optical absorption of sodium copper chlorophyllin thin films in UV-vis-NIR region.

    Science.gov (United States)

    Farag, A A M

    2006-11-01

    The optical absorption studies of sodium copper chlorophyllin thin films (SCC), prepared by spray pyrolysis, in the UV-vis-NIR region was reported for the first time. Several new discrete transitions are observed in the UV-vis region of the spectra in addition to a strong continuum component in the IR region. The spectra of the infrared absorption allow characterization of vibration modes for the powder and thin films of SCC. The absorption spectrum recorded in the UV-vis region showed different absorption bands, namely the Soret (B) in the region 340-450 nm and Q-band in the region 600-700 nm and other band labeled N in the 240-320 region. Some important spectral parameters namely optical absorption coefficient (alpha), molar extinction coefficient (epsilon(molar)), oscillator strength (f), electric dipole strength (q(2)) and absorption half bandwidth (Deltalambda) of the principle optical transitions were evaluated. The analysis of the absorption coefficient in the absorption region revealed direct transitions and the energy gap was estimated as 1.63 eV. Discussion of the obtained results and their comparison with the previous published data are also given.

  4. Emission and Absorption Entropy Generation in Semiconductors

    DEFF Research Database (Denmark)

    Reck, Kasper; Varpula, Aapo; Prunnila, Mika

    2013-01-01

    While emission and absorption entropy generation is well known in black bodies, it has not previously been studied in semiconductors, even though semiconductors are widely used for solar light absorption in modern solar cells [1]. We present an analysis of the entropy generation in semiconductor...... materials due to emission and absorption of electromagnetic radiation. It is shown that the emission and absorption entropy generation reduces the fundamental limit on the efficiency of any semiconductor solar cell even further than the Landsberg limit. The results are derived from purely thermodynamical...

  5. Differential Photoacoustic Particle Absorption Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We developed a highly sensitive and compact instrument to directly measure particulate matter (PM) optical absorption. This device is based on differential...

  6. Absorption enhancement in graphene photonic crystal structures.

    Science.gov (United States)

    Khaleque, Abdul; Hattori, Haroldo T

    2016-04-10

    Graphene, a single layer of carbon atoms arranged in a honeycomb lattice, is attracting significant interest because of its potential applications in electronic and optoelectronic devices. Although graphene exhibits almost uniform absorption within a large wavelength range, its interaction with light is weak. In this paper, the enhancement of the optical absorption in graphene photonic crystal structures is studied: the structure is modified by introducing scatterers and mirrors. It is shown that the absorption of the graphene photonic crystal structure can be enhanced about four times (nearly 40%) with respect to initial reference absorption of 9.8%. The study can be a useful tool for investigating graphene physics in different optical settings.

  7. X-ray absorption in atomic potassium

    International Nuclear Information System (INIS)

    Gomilsek, Jana Padeznik; Kodre, Alojz; Arcon, Iztok; Nemanic, Vincenc

    2008-01-01

    A new high-temperature absorption cell for potassium vapor is described. X-ray absorption coefficient of atomic potassium is determined in the energy interval of 600 eV above the K edge where thresholds for simultaneous excitations of 1s and outer electrons, down to [1s2p] excitation, appear. The result represents also the atomic absorption background for XAFS (X-ray absorption fine structure) structure analysis. The K ionization energy in the potassium vapor is determined and compared with theoretical data and with the value for the metal

  8. Cryo-Infrared Optical Characterization at NASA GSFC

    Science.gov (United States)

    Boucarut, Ray; Quijada, Manuel A.; Henry, Ross M.

    2004-01-01

    The development of large space infrared optical systems, such as the Next Generation Space Telescope (NGST), has increased requirements for measurement accuracy in the optical properties of materials. Many materials used as optical components in infrared optical systems, have strong temperature dependence in their optical properties. Unfortunately, data on the temperature dependence of most of these materials is sparse. In this paper, we provide a description of the capabilities existing in the Optics Branch at the Goddard Space Flight Center that enable the characterization of the refractive index and absorption coefficient changes and other optical properties in infrared materials at cryogenic temperatures. Details of the experimental apparatus, which include continuous flow liquid helium optical cryostat, and a Fourier Transform Infrared (FTIR) spectrometer are discussed.

  9. CANISTER HANDLING FACILITY DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    Beesley. J.F.

    2005-01-01

    The purpose of this facility description document (FDD) is to establish requirements and associated bases that drive the design of the Canister Handling Facility (CHF), which will allow the design effort to proceed to license application. This FDD will be revised at strategic points as the design matures. This FDD identifies the requirements and describes the facility design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This FDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This FDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the facility. Knowledge of these requirements is essential in performing the design process. The FDD follows the design with regard to the description of the facility. The description provided in this FDD reflects the current results of the design process

  10. CANISTER HANDLING FACILITY DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    J.F. Beesley

    2005-04-21

    The purpose of this facility description document (FDD) is to establish requirements and associated bases that drive the design of the Canister Handling Facility (CHF), which will allow the design effort to proceed to license application. This FDD will be revised at strategic points as the design matures. This FDD identifies the requirements and describes the facility design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This FDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This FDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the facility. Knowledge of these requirements is essential in performing the design process. The FDD follows the design with regard to the description of the facility. The description provided in this FDD reflects the current results of the design process.

  11. Fuel Handling Facility Description Document

    International Nuclear Information System (INIS)

    M.A. LaFountain

    2005-01-01

    The purpose of the facility description document (FDD) is to establish the requirements and their bases that drive the design of the Fuel Handling Facility (FHF) to allow the design effort to proceed to license application. This FDD is a living document that will be revised at strategic points as the design matures. It identifies the requirements and describes the facility design as it currently exists, with emphasis on design attributes provided to meet the requirements. This FDD was developed as an engineering tool for design control. Accordingly, the primary audience and users are design engineers. It leads the design process with regard to the flow down of upper tier requirements onto the facility. Knowledge of these requirements is essential to performing the design process. It trails the design with regard to the description of the facility. This description is a reflection of the results of the design process to date

  12. Description du langage scientifique (Description of Scientific Language)

    Science.gov (United States)

    Widdowson, H. G.

    1977-01-01

    A description of scientific language using three approaches: text, textualization, and discourse. Scientific discourse is analogous to universal deep structure; text, to surface variations in diverse languages; and textualization, to transformational processes. The relationship of the primary and secondary (scientific) cultures and their languages…

  13. Auteur Description: From the Director's Creative Vision to Audio Description

    Science.gov (United States)

    Szarkowska, Agnieszka

    2013-01-01

    In this report, the author follows the suggestion that a film director's creative vision should be incorporated into Audio description (AD), a major technique for making films, theater performances, operas, and other events accessible to people who are blind or have low vision. The author presents a new type of AD for auteur and artistic films:…

  14. CHARACTERIZATION OF PEOPLE IN CARDIAC SURGERIES: A DESCRIPTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Keila Maria Azevedo Ponte

    2013-03-01

    Full Text Available Objetivo: Caracterizar os pacientes submetidos à cirurgia cardíaca em hospital de referência da região norte do Ceará. Metodologia: Estudo descritivo, retrospectivo e documental realizado pela análise de 176 prontuários de acordo com os aspectos éticos da resolução 196/96. Resultados: Identificou-se predominância de pacientes masculinos, casados, residentes em municípios distantes do serviço de saúde com predomínio da faixa etária acima de 40 anos. A permanência hospitalar foi baixa e por isso, percebe-se redução de riscos relacionados à internação e também dos custos com estes serviços, os quais influenciam para o aumento da rotatividade e disponibilização de leitos. Discussão: Foi evidenciada grande rotatividade e efetividade do serviço, possibilitando também vislumbrar que a principal cirurgia realizada é a revascularização do miocárdio em homens com a duração de internação em torno de quatro dias. Conclusão: Apesar dos riscos de uma cirurgia cardiovascular no hospital estudado, os pacientes recuperam-se com grande sucesso.

  15. Infrared multiphoton absorption and decomposition

    International Nuclear Information System (INIS)

    Evans, D.K.; McAlpine, R.D.

    1984-01-01

    The discovery of infrared laser induced multiphoton absorption (IRMPA) and decomposition (IRMPD) by Isenor and Richardson in 1971 generated a great deal of interest in these phenomena. This interest was increased with the discovery by Ambartzumian, Letokhov, Ryadbov and Chekalin that isotopically selective IRMPD was possible. One of the first speculations about these phenomena was that it might be possible to excite a particular mode of a molecule with the intense infrared laser beam and cause decomposition or chemical reaction by channels which do not predominate thermally, thus providing new synthetic routes for complex chemicals. The potential applications to isotope separation and novel chemistry stimulated efforts to understand the underlying physics and chemistry of these processes. At ICOMP I, in 1977 and at ICOMP II in 1980, several authors reviewed the current understandings of IRMPA and IRMPD as well as the particular aspect of isotope separation. There continues to be a great deal of effort into understanding IRMPA and IRMPD and we will briefly review some aspects of these efforts with particular emphasis on progress since ICOMP II. 31 references

  16. Absorption of ozone by porous particles

    Energy Technology Data Exchange (ETDEWEB)

    Afanas' ev, V.P.; Dorofeev, S.B.; Sinitsyn, V.I.; Smirnov, B.M.

    1981-11-01

    The absorption of ozone by porous zeolite, silica gel, and activated carbon particles has been studied experimentally. It was shown that in addition to absorption, dissociation of ozone on the surface plays an important and sometimes decisive role. The results obtained were used to analyze the nature of ball lightning.

  17. A transient absorption study of allophycocyanin

    Indian Academy of Sciences (India)

    Transient dynamics of allophycocyanin trimers and monomers are observed by using the pump-probe, transient absorption technique. The origin of spectral components of the transient absorption spectra is discussed in terms of both kinetics and spectroscopy. We find that the energy gap between the ground and excited ...

  18. Probing ultrafast carrier dynamics, nonlinear absorption and ...

    Indian Academy of Sciences (India)

    diameter of about 60 nm of the core–shell silicon nanowires, (b) linear optical absorption measurement using a visible–infrared absorption spectrometer. on the nanowires and on the substrate [9]. The overall thickness of the silicon nanowire film was ∼600 nm measured independently using atomic force microscopy ...

  19. Regularity of the interband light absorption coefficient

    Indian Academy of Sciences (India)

    In experimental studies the absorption coefficient is a means to study the band gaps at ... to l2( ), where. ⊂ Zd is a finite set. (usually taken to be a lattice cube centred at the origin) and λ±,uλ± are eigenvalues and eigenfunctions of H. ±. ,ω . Then the interband light absorption coefficient A for such finite volume models can.

  20. Anomalous infrared absorption in granular superconductors

    International Nuclear Information System (INIS)

    Carr, G.L.; Garland, J.C.; Tanner, D.B.

    1983-01-01

    Granular superconductors are shown to have a far-infrared absorption that is larger when the samples are superconducting than when they are normal. By constrast, theoretical models for these materials predict that when the samples become superconducting, the absorption should decrease

  1. A Low-Cost Quantitative Absorption Spectrophotometer

    Science.gov (United States)

    Albert, Daniel R.; Todt, Michael A.; Davis, H. Floyd

    2012-01-01

    In an effort to make absorption spectrophotometry available to high school chemistry and physics classes, we have designed an inexpensive visible light absorption spectrophotometer. The spectrophotometer was constructed using LEGO blocks, a light emitting diode, optical elements (including a lens), a slide-mounted diffraction grating, and a…

  2. Terahertz absorption spectrum of triacetone triperoxide (TATP)

    Science.gov (United States)

    Wilkinson, John; Konek, Christopher T.; Moran, Jesse S.; Witko, Ewelina M.; Korter, Timothy M.

    2009-08-01

    We report here, for the first time, the terahertz absorption spectrum of triacetone triperoxide (TATP). The experimental spectra are coupled with solid-state density functional theory, and preliminary assignments are provided to gain physical insight into the experimental spectrum. The calculated absorption coefficients are in excellent agreement with experiment.

  3. Absorption of sound by tree bark

    Science.gov (United States)

    G. Reethof; L. D. Frank; O. H. McDaniel

    1976-01-01

    Laboratory tests were conducted with a standing wave tube to measure the acoustic absorption of normally incident sound by the bark of six species of trees. Twelve bark samples, 10 cm in diameter, were tested. Sound of seven frequencies between 400 and 1600 Hz was used in the measurements. Absorption was generally about 5 percent; it exceeded 10 percent for only three...

  4. Spectral interferences in atomic absorption spectrometry, (5)

    International Nuclear Information System (INIS)

    Daidoji, Hidehiro

    1979-01-01

    Spectral interferences were observed in trace element analysis of concentrated solutions by atomic absorption spectrometry. Molecular absorption and emission spectra for strontium chloride and nitrate, barium chloride and nitrate containing 12 mg/ml of metal ion in airacetylene flame were measured in the wavelength range from 200 to 700 nm. The absorption and emission spectra of SrO were centered near 364.6 nm. The absorption spectra of SrOH around 606.0, 671.0 and 682.0 nm were very strong. And, emission spectrum of BaOH in the wavelength range from 480 to 550 nm was stronger. But, the absorption of this band spectrum was very weak. In the wavelength range from 200 to 400 nm, some unknown bands of absorption were observed for strontium and barium. Absorption spectra of SrCl and BaCl were observed in the argon-hydrogen flame. Also, in the carbon tube atomizer, the absorption spectra of SrCl and BaCl were detected clearly in the wavelength range from 185 to 400 nm. (author)

  5. Calculated optical absorption of different perovskite phases

    DEFF Research Database (Denmark)

    Castelli, Ivano Eligio; Thygesen, Kristian Sommer; Jacobsen, Karsten Wedel

    2015-01-01

    of perovskites the solar light absorption efficiency varies greatly depending not only on bandgap size and character (direct/indirect) but also on the dipole matrix elements. The oxides exhibit generally a fairly weak absorption efficiency due to indirect bandgaps while the most efficient absorbers are found...

  6. Flue gas treatment with membrane gas absorption

    NARCIS (Netherlands)

    Klaassen, R.; Feron, P.H.M.; Jansen, A.E.

    1998-01-01

    Dutch researchers from the TN0 Institute have developed a technique to carry out gas-liquid contacting operations using hollow fibre membranes in combination with an absorption liquid. The method known as membrane gas absorption, aims to combine the advantages of membrane technology (compactness,

  7. Cosmic radio-noise absorption bursts caused by solar wind shocks

    Directory of Open Access Journals (Sweden)

    A. Osepian

    2004-09-01

    Full Text Available Bursts of cosmic noise absorption observed at times of sudden commencements (SC of geomagnetic storms are examined. About 300SC events in absorption for the period 1967-1990 have been considered. It is found that the response of cosmic radio-noise absorption to the passage of an interplanetary shock depends on the level of the planetary magnetic activity preceding the SC event and on the magnitude of the magnetic field perturbation associated with the SC (as measured in the equatorial magnetosphere. It is shown that for SC events observed against a quiet background (Kp<2, the effects of the SC on absorption can be seen only if the magnitude of the geomagnetic field perturbation caused by the solar wind shock exceeds a threshold value ΔBth. It is further demonstrated that the existence of this threshold value, ΔBth, deduced from experimental data, can be related to the existence of a threshold for exciting and maintaining the whistler cyclotron instability, as predicted by quasi-linear theory. SC events observed against an active background (Kp<2 are accompanied by absorption bursts for all magnetic field perturbations, however small. A quantitative description of absorption bursts associated with SC events is provided by the whistler cyclotron instability theory.

  8. Report on the remedial investigation of Bear Creek Valley at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 2: Appendix A -- Waste sites, source terms, and waste inventory report; Appendix B -- Description of the field activities and report database; Appendix C -- Characterization of hydrogeologic setting report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This Remedial Investigation (RI) Report characterizes the nature and extent of contamination, evaluates the fate and transport of contaminants, and assesses risk to human health and the environment resulting from waste disposal and other US Department of Energy (DOE) operations in Bear Creek Valley (BCV). BCV, which is located within the DOE Oak Ridge Reservation (ORR) encompasses multiple waste units containing hazardous and radioactive wastes arising from operations at the adjacent Oak Ridge Y-12 Plant. The primary waste units discussed in this RI Report are the S-3 Site, Oil Landfarm (OLF), Boneyard/Burnyard (BYBY), Sanitary Landfill 1 (SL 1), and Bear Creek Burial Grounds (BCBG). These waste units, plus the contaminated media resulting from environmental transport of the wastes from these units, are the subject of this RI. This BCV RI Report represents the first major step in the decision-making process for the BCV watershed. The RI results, in concert with the follow-on FS will form the basis for the Proposed Plan and Record of Decision for all BCV sites. This comprehensive decision document process will meet the objectives of the watershed approach for BCV. Appendix A includes descriptions of waste areas and estimates of the current compositions of the wastes. Appendix B contains an extensive database of environmental data for the Bear Creek Valley Characterization Area. Information is also presented about the number and location of samples collected, the analytes examined, and the extent of data validation. Appendix C describes the hydrogeologic conceptual model for Bear Creek Valley. This model is one of the principal components of the conceptual site models for contaminant transport in BCV.

  9. Report on the remedial investigation of Bear Creek Valley at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 2: Appendix A - Waste sites, source terms, and waste inventory report; Appendix B - Description of the field activities and report database; Appendix C - Characterization of hydrogeologic setting report

    International Nuclear Information System (INIS)

    1996-01-01

    This Remedial Investigation (RI) Report characterizes the nature and extent of contamination, evaluates the fate and transport of contaminants, and assesses risk to human health and the environment resulting from waste disposal and other US Department of Energy (DOE) operations in Bear Creek Valley (BCV). BCV, which is located within the DOE Oak Ridge Reservation (ORR) encompasses multiple waste units containing hazardous and radioactive wastes arising from operations at the adjacent Oak Ridge Y-12 Plant. The primary waste units discussed in this RI Report are the S-3 Site, Oil Landfarm (OLF), Boneyard/Burnyard (BYBY), Sanitary Landfill 1 (SL 1), and Bear Creek Burial Grounds (BCBG). These waste units, plus the contaminated media resulting from environmental transport of the wastes from these units, are the subject of this RI. This BCV RI Report represents the first major step in the decision-making process for the BCV watershed. The RI results, in concert with the follow-on FS will form the basis for the Proposed Plan and Record of Decision for all BCV sites. This comprehensive decision document process will meet the objectives of the watershed approach for BCV. Appendix A includes descriptions of waste areas and estimates of the current compositions of the wastes. Appendix B contains an extensive database of environmental data for the Bear Creek Valley Characterization Area. Information is also presented about the number and location of samples collected, the analytes examined, and the extent of data validation. Appendix C describes the hydrogeologic conceptual model for Bear Creek Valley. This model is one of the principal components of the conceptual site models for contaminant transport in BCV

  10. Electrochemical synthesis and spectroscopic characterization of ...

    African Journals Online (AJOL)

    phenylpyrrole) coatings in an organic medium on iron and platinum electrodes. ... XPS measurements, infrared (FT-IR) and electronic absorption (UV-vis) spectroscopies were used to characterize the iron and platinum-coated electrodes. Finally the ...

  11. Absorption of controlled-release iron

    International Nuclear Information System (INIS)

    Cook, J.D.; Lipschitz, D.A.; Skikne, B.S.

    1982-01-01

    A multiple-dose double radioiron technic was used to compare absorption of iron administered as a controlled release (CR) capsule and as an elixir; both formulations contained 50 mg elemental iron as ferrous sulfate. When taken by normal subjects in the fasting state, mean absorption from the elixir and CR capsule averaged 4.92% and 4.38%, which gave a CR capsule:elixir ratio of 0.89. This difference was not significant, but when taken with meals that inhibit absorption of dietary iron by different degrees, absorption of the CR formulation was superior. CR capsule:elixir absorption ratios averaged 1.70 from a meal that is mildly inhibitory and 3.13 from a meal that causes more marked inhibition. It is concluded that CR iron formulations may offer a therapeutic advantage to patients who take oral iron with meals to avoid gastrointestinal side effects

  12. Thorax X-ray diagnostics. DDS (double base description system). Uniform terminology and standardized sytematics. Correct diagnosis

    International Nuclear Information System (INIS)

    Kulke, H.M.

    2012-01-01

    The booklet describes the so called DDS (double-base description system) to be used in the frame of medical thorax X-ray examinations with modern imaging devices. The following issues are discussed: Description features, shadow characterization, general fundamentals, procedural methodology, diagnostic findings protocol, examples and case descriptions.

  13. Geotechnical Description of Mineral Deposits

    Directory of Open Access Journals (Sweden)

    Sasvári Tibor

    1996-06-01

    Full Text Available Performing various mineral deposits extraction methods requires thorough knowledge of the rock masses` geomechanical parameters. In the geotechnical description of mineral deposits there is proposed a methodical approarch at the collection, registration, and evaluation of rock masses` geological properties for geotechnics being applied within the mining industry.

  14. Natural Language Description of Emotion

    Science.gov (United States)

    Kazemzadeh, Abe

    2013-01-01

    This dissertation studies how people describe emotions with language and how computers can simulate this descriptive behavior. Although many non-human animals can express their current emotions as social signals, only humans can communicate about emotions symbolically. This symbolic communication of emotion allows us to talk about emotions that we…

  15. Task descriptions versus use cases

    DEFF Research Database (Denmark)

    Lauesen, Søren; Kuhail, Mohammad Amin

    2011-01-01

    project: Acquire a new system to support a hotline. Among the 15 replies, eight used traditional use cases that specified a dialog between user and system. Seven used a related technique, task description, which specified the customer’s needs without specifying a dialog. It also allowed the analyst...

  16. The geometry description markup language

    International Nuclear Information System (INIS)

    Chytracek, R.

    2001-01-01

    Currently, a lot of effort is being put on designing complex detectors. A number of simulation and reconstruction frameworks and applications have been developed with the aim to make this job easier. A very important role in this activity is played by the geometry description of the detector apparatus layout and its working environment. However, no real common approach to represent geometry data is available and such data can be found in various forms starting from custom semi-structured text files, source code (C/C++/FORTRAN), to XML and database solutions. The XML (Extensible Markup Language) has proven to provide an interesting approach for describing detector geometries, with several different but incompatible XML-based solutions existing. Therefore, interoperability and geometry data exchange among different frameworks is not possible at present. The author introduces a markup language for geometry descriptions. Its aim is to define a common approach for sharing and exchanging of geometry description data. Its requirements and design have been driven by experience and user feedback from existing projects which have their geometry description in XML

  17. Marketing and Merchandising, Course Description.

    Science.gov (United States)

    Boyer, Jerome L.; Anderson, Floyd L.

    This course description was developed by educators for use at the Work Opportunity Center which was established to teach high school dropouts and/or hard-core unemployed youth. The ultimate objectives of the marketing and merchandising curriculum are to prepare students for careers in distribution and to assist them in graduating from high school.…

  18. Use cases versus task descriptions

    DEFF Research Database (Denmark)

    Lauesen, Søren; Kuhail, Mohammad Amin

    2011-01-01

    to specify require-ments for the same project: Acquire a new system to support a hotline. [Princi-pal ideas/results] Among the 15 replies, eight used traditional use cases that specified a dialog between users and system. Seven used a related technique, task description, which specified the customer's needs...

  19. Epsilon. A System Description Language

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kyng, Morten

    This paper discusses the use of Petri nets as a semantic tool in the design of languages and in the construction and analysis of system descriptions. The topics treated are: -- Languages based on nets. -- The problem of time in nets. -- Nets and related models. -- Nets and formal semantics...

  20. THE SPANISH SCIENTIFIC JOURNALS: A DESCRIPTIVE APPROACH

    Directory of Open Access Journals (Sweden)

    Melba G. Claudio-González

    2017-02-01

    Full Text Available The main objective of this article is to present a broad description of Spanish scientific journals. The results were obtained from a survey distributed to 1,280 editors of Spanish scientific journals included in Dulcinea database (2012 edition. The response rate was 43,8%. As specific objectives, the study aimed to characterize scientific journals and to analyze the particularities of a set of parameters that make up the economic, strategic and operational dimensions of the journals in the period studied. The results show that the funding model of the Spanish scientific journals depends mainly on institutional support, that many journals lack a stable organizational structure and rely heavily on volunteer work, and that the debate on the limitations and difficulties affecting the development of open access remains open.

  1. Generalized Probabilistic Description of Noninteracting Identical Particles

    Science.gov (United States)

    Karczewski, Marcin; Markiewicz, Marcin; Kaszlikowski, Dagomir; Kurzyński, Paweł

    2018-02-01

    We investigate an operational description of identical noninteracting particles in multiports. In particular, we look for physically motivated restrictions that explain their bunching probabilities. We focus on a symmetric 3-port in which a triple of superquantum particles admitted by our generalized probabilistic framework would bunch with a probability of 3/4 . The bosonic bound of 2/3 can then be restored by imposing the additional requirement of product evolution of certain input states. These states are characterized by the fact that, much like product states, their entropy equals the sum of entropies of their one-particle substates. This principle is, however, not enough to exclude the possibility of superquantum particles in higher-order multiports.

  2. Mixture component effects on the in vitro dermal absorption of pentachlorophenol

    Energy Technology Data Exchange (ETDEWEB)

    Riviere, J.E.; Qiao, G.; Baynes, R.E.; Brooks, J.D. [Coll. of Veterinary Medicine, North Carolina State Univ., Raleigh, NC (United States); Mumtaz, M. [Agency for Toxic Substances and Disease Registry (ATSDR), Atlanta, GA (United States)

    2001-08-01

    Interactions between chemicals in a mixture and interactions of mixture components with the skin can significantly alter the rate and extent of percutaneous absorption, as well as the cutaneous disposition of a topically applied chemical. The predictive ability of dermal absorption models, and consequently the dermal risk assessment process, would be greatly improved by the elucidation and characterization of these interactions. Pentachlorophenol (PCP), a compound known to penetrate the skin readily, was used as a marker compound to examine mixture component effects using in vitro porcine skin models. PCP was administered in ethanol or in a 40% ethanol/60% water mixture or a 40% ethanol/60% water mixture containing either the rubefacient methyl nicotinate (MNA) or the surfactant sodium lauryl sulfate (SLS), or both MNA and SLS. Experiments were also conducted with {sup 14}C-labelled 3,3',4,4'-tetrachlorobiphenyl (TCB) and 3,3',4,4',5-pentachlorobiphenyl (PCB). Maximal PCP absorption was 14.12% of the applied dose from the mixture containing SLS, MNA, ethanol and water. However, when PCP was administered in ethanol only, absorption was only 1.12% of the applied dose. There were also qualitative differences among the absorption profiles for the different PCP mixtures. In contrast with the PCP results, absorption of TCB or PCB was negligible in perfused porcine skin, with only 0.14% of the applied TCB dose and 0.05% of the applied PCB dose being maximally absorbed. The low absorption levels for the PCB congeners precluded the identification of mixture component effects. These results suggest that dermal absorption estimates from a single chemical exposure may not reflect absorption seen after exposure as a chemical mixture and that absorption of both TCB and PCB are minimal in this model system. (orig.)

  3. Sound absorption study of raw and expanded particulate vermiculites

    Science.gov (United States)

    Vašina, Martin; Plachá, Daniela; Mikeska, Marcel; Hružík, Lumír; Martynková, Gražyna Simha

    2016-12-01

    Expanded and raw vermiculite minerals were studied for their ability to absorb sound. Phase and structural characterization of the investigated vermiculites was found similar for both types, while morphology and surface properties vary. Sound waves reflect in wedge-like structure and get minimized, and later are absorbed totally. We found that thanks to porous character of expanded vermiculite the principle of absorption of sound into layered vermiculite morphology is analogous to principle of sound minimization in "anechoic chambers." It was found in this study that the best sound damping properties of the investigated vermiculites were in general obtained at higher powder bed heights and higher excitation frequencies.

  4. Lowest excited states and optical absorption spectra of donor–acceptor copolymers for organic photovoltaics: a new picture emerging from tuned long-range corrected density functionals

    KAUST Repository

    Pandey, Laxman

    2012-01-01

    Polymers with low optical gaps are of importance to the organic photovoltaics community due to their potential for harnessing a large portion of the solar energy spectrum. The combination along their backbones of electron-rich and electron-deficient fragments contributes to the presence of low-lying excited states that are expected to display significant charge-transfer character. While conventional hybrid functionals are known to provide unsatisfactory results for charge-transfer excitations at the time-dependent DFT level, long-range corrected (LRC) functionals have been reported to give improved descriptions in a number of systems. Here, we use such LRC functionals, considering both tuned and default range-separation parameters, to characterize the absorption spectra of low-optical-gap systems of interest. Our results indicate that tuned LRC functionals lead to simulated optical-absorption properties in good agreement with experimental data. Importantly, the lowest-lying excited states (excitons) are shown to present a much more localized nature than initially anticipated. © 2012 the Owner Societies.

  5. CRACUK model description (appendices to the CRAC2 model description)

    International Nuclear Information System (INIS)

    Nixon, W.; Egan, M.J.

    1986-08-01

    The CRACUK computer code is a revised version of the US consequence modelling code CRAC2, adapted to suit UK requirements. The revisions include modifications to the models for spatial interval representation, weather sequence sampling, atmospheric dispersion, dosimetry and countermeasures. This document describes, in the form of appendices to the CRAC2 model description, each of the revisions made to the original model which collectively distinguish CRACUK from CRAC2. (author)

  6. Pathlength Determination for Gas in Scattering Media Absorption Spectroscopy

    Science.gov (United States)

    Mei, Liang; Somesfalean, Gabriel; Svanberg, Sune

    2014-01-01

    Gas in scattering media absorption spectroscopy (GASMAS) has been extensively studied and applied during recent years in, e.g., food packaging, human sinus monitoring, gas diffusion studies, and pharmaceutical tablet characterization. The focus has been on the evaluation of the gas absorption pathlength in porous media, which a priori is unknown due to heavy light scattering. In this paper, three different approaches are summarized. One possibility is to simultaneously monitor another gas with known concentration (e.g., water vapor), the pathlength of which can then be obtained and used for the target gas (e.g., oxygen) to retrieve its concentration. The second approach is to measure the mean optical pathlength or physical pathlength with other methods, including time-of-flight spectroscopy, frequency-modulated light scattering interferometry and the frequency domain photon migration method. By utilizing these methods, an average concentration can be obtained and the porosities of the material are studied. The last method retrieves the gas concentration without knowing its pathlength by analyzing the gas absorption line shape, which depends upon the concentration of buffer gases due to intermolecular collisions. The pathlength enhancement effect due to multiple scattering enables also the use of porous media as multipass gas cells for trace gas monitoring. All these efforts open up a multitude of different applications for the GASMAS technique. PMID:24573311

  7. Pathlength Determination for Gas in Scattering Media Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Liang Mei

    2014-02-01

    Full Text Available Gas in scattering media absorption spectroscopy (GASMAS has been extensively studied and applied during recent years in, e.g., food packaging, human sinus monitoring, gas diffusion studies, and pharmaceutical tablet characterization. The focus has been on the evaluation of the gas absorption pathlength in porous media, which a priori is unknown due to heavy light scattering. In this paper, three different approaches are summarized. One possibility is to simultaneously monitor another gas with known concentration (e.g., water vapor, the pathlength of which can then be obtained and used for the target gas (e.g., oxygen to retrieve its concentration. The second approach is to measure the mean optical pathlength or physical pathlength with other methods, including time-of-flight spectroscopy, frequency-modulated light scattering interferometry and the frequency domain photon migration method. By utilizing these methods, an average concentration can be obtained and the porosities of the material are studied. The last method retrieves the gas concentration without knowing its pathlength by analyzing the gas absorption line shape, which depends upon the concentration of buffer gases due to intermolecular collisions. The pathlength enhancement effect due to multiple scattering enables also the use of porous media as multipass gas cells for trace gas monitoring. All these efforts open up a multitude of different applications for the GASMAS technique.

  8. Inferring Aerosol Angstrom Absorption Exponent using satellite observations

    Science.gov (United States)

    Torres, O.; Bhartia, P. K.; Jethva, H. T.; Ahn, C.

    2013-12-01

    The Angstrom Absorption Exponent (AAE) is a parameter commonly used to characterize the wavelength-dependence of aerosol absorption optical depth (AAOD). It is closely related to aerosol composition. Black carbon (BC) containing aerosols yield AAE values near unity whereas Organic carbon (OC) aerosol particles are associated with values larger than 2. Even larger AAE values have been reported for desert dust aerosol particles. Knowledge of spectral AAOD is necessary for the calculation of direct radiative forcing effect of aerosols and for inferring aerosol composition. We have developed a satellite-based method of determining the spectral AAOD of absorbing aerosols. The technique uses multi-spectral measurements of upwelling radiation from scenes where absorbing aerosols are present above clouds. The upwelling reflectance at the cloud top is attenuated by the absorption effects of the overlying aerosol layer. This attenuation effect can be described using an approximations of Beer's Law. The upwelling reflectance at the cloud-top in an aerosol-free atmospheric column is mainly a function of cloud optical depth (COD). In the proposed method of AAE derivation, the first step is determining COD which is retrieved using a previously developed color-ratio based approach. In the second step, the spectral AAOD is derived by an inversion of the measured spectral reflectance. The proposed technique will be discussed and application results making use of OMI multi-spectral measurements in the UV-Vis. will be presented.

  9. Strong saturable absorption of black titanium oxide nanoparticle films

    Science.gov (United States)

    Zhang, Rong-Fang; Guo, Deng-Zhu; Zhang, Geng-Min

    2017-12-01

    Nonlinear optical materials with strong saturable absorption (SA) properties play an essential role in passive mode-locking generation of ultrafast lasers. Here we report black TiO2-x nanoparticles are promising candidate for such an application. Black TiO2-x nanoparticles are synthesized by using cathodic plasma electrolysis, and nanoparticle films are deposited on optical glass plates via natural sedimentation and post annealing. Characterization of the samples with TEM, SEM, XRD and XPS reveal that nanoparticles have diameters of 8-70 nm, and are in polycrystalline structure and co-existence of anatase, rutile and abundant oxygen-deficient phases. Optical transmittance and reflectance measurements with a UV/VIS/NIR spectrophotometer evidence an excellent wide-spectral optical absorption property. The nonlinear optical properties of the samples were measured by using open-aperture Z-scan technique with picosecond 532-nm laser, and verified by direct transmission measurements using nanosecond 1064-nm laser. Strong SA behavior was detected, and the nonlinear absorption coefficient is as high as β = - 4.9 × 10-8 m/W, at least two orders larger than most previous reports on ordinary TiO2. The strong SA behaviors are ascribed to the existence of plenty surface states and defect states within bandgap, and the relaxation rates of electrons from upper energy levels to lower ones are much slower than excitation rates.

  10. Synthesis and microwave absorption properties of PPy/Co nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Juhua, E-mail: luojuhua@163.com [School of Materials Engineering, Yancheng Institute of Technology, Yancheng 224051 (China); Gao, Duoduo [School of Material Science and Engineering, Changzhou University, Changzhou 213164 (China)

    2014-11-15

    Polypyrrole (PPy)/cobalt (Co) nanocomposites were successfully prepared by an in-situ polymerization of pyrrole in the presence of synthesized Co nanoparticles. Characterization of the product was accomplished by XRD, TEM, FT-IR, VSM, and vector network analyzer techniques. XRD analysis revealed that characteristic diffraction peaks of polypyrrole and Co appeared at the same time in nanocomposites. FT-IR analysis indicated a successful conjugation of Co particles with polypyrrole. TEM confirmed the formation of a core-shell structure with a wide particle size distribution. Magnetization measurements showed that polypyrrole coating decreased the saturation magnetization of Co significantly. With the increase of the matching thickness, the absorption peak varied towards low frequency direction. When the matching thickness was 3.0 mm, the value of the maximum reflection loss (RL) was −20.0 dB at 13.8 GHz with the 7.2 GHz bandwidth. - Highlights: • The influence of PPy on the structure of Co is discussed. • The influence of PPy on the magnetic properties of Co is discussed. • The influence of PPy on the absorption property of Co is discussed. • PPy/Co possessed the excellent absorption property.

  11. Relationship between mechanical-property and energy-absorption trends for composite tubes

    Science.gov (United States)

    Farley, Gary L.

    1992-01-01

    U.S. Army helicopters are designed to dissipate prescribed levels of crash impact kinetic energy without compromising the integrity of the fuselage. Because of the complexity of the energy-absorption process it is imperative for designers of energy-absorbing structures to develop an in-depth understanding of how and why composite structures absorb energy. A description of the crushing modes and mechanisms of energy absorption for composite tubes and beams is presented. Three primary crushing modes of composite structures including transverse shearing, lamina bending, and local buckling are described. The experimental data presented show that fiber and matrix mechanical properties and laminate stiffness and strength mechanical properties cannot reliably predict the energy-absorption response of composite tubes.

  12. A LiBr-H2O Absorption Refrigerator Incorporating a Thermally Activated Solution Pumping Mechanism

    OpenAIRE

    Ian W. Eames

    2017-01-01

    This paper provides an illustrated description of a proposed LiBr-H2O vapour absorption refrigerator which uses a thermally activated solution pumping mechanism that combines controlled variations in generator vapour pressure with changes it produces in static-head pressure difference to circulate the absorbent solution between the generator and absorber vessels. The proposed system is different and potentially more efficient than a bubble pump system previously proposed and avoids the need f...

  13. Aerosol Angstrom Absorption Coefficient Comparisons during MILAGRO.

    Science.gov (United States)

    Marley, N. A.; Marchany-Rivera, A.; Kelley, K. L.; Mangu, A.; Gaffney, J. S.

    2007-12-01

    Measurements of aerosol absorption were obtained as part of the MAX-Mex component of the MILAGRO field campaign at site T0 (Instituto Mexicano de Petroleo in Mexico City) by using a 7-channel aethalometer (Thermo- Anderson) during the month of March, 2006. The absorption measurements obtained in the field at 370, 470, 520, 590, 660, 880, and 950 nm were used to determine the aerosol Angstrom absorption exponents by linear regression. Since, unlike other absorbing aerosol species (e.g. humic like substances, nitrated PAHs), black carbon absorption is relatively constant from the ultraviolet to the infrared with an Angstrom absorption exponent of -1 (1), a comparison of the Angstrom exponents can indicate the presence of aerosol components with an enhanced UV absorption over that expected from BC content alone. The Angstrom exponents determined from the aerosol absorption measurements obtained in the field varied from - 0.7 to - 1.3 during the study and was generally lower in the afternoon than the morning hours, indicating an increase in secondary aerosol formation and photochemically generated UV absorbing species in the afternoon. Twelve-hour integrated samples of fine atmospheric aerosols (Petroleo (IMP) and CENICA.

  14. Gastrointestinal absorption of Np in rats

    International Nuclear Information System (INIS)

    Wirth, R.; Volf, V.

    1985-01-01

    The effect of Np mass and the acidity of the administered Np solutions as well as the age, sex and nutritional status of the animals injected or gavaged with 239Np or 237Np were determined. The latter factor proved to be dominant for absorption of Np from the gut. Thus in fasting weanling and young adult male rats, the absorption of 239Np was sixfold higher (0.18% and 0.12%, respectively) than in fed ones (0.03% and 0.02%, respectively). Absorption by fasted adult females was 0.05% of the administered 239Np, about half of that of adult males. Raising the Np-mass gavaged to fasted female rats to 1 and 10 mg 237Np/kg resulted in an absorption of 0.23% and 0.26%, respectively. Thus, an increased absorption of Np in adult rats seems to be expected only if a large mass is ingested. No dependence of the absorption of Np on nitric acid concentration was found. The data obtained after oral administration of 238Pu and 239Np to adult rats suggest that the f1 factor recommended by the ICRP for fractional absorption of soluble Np compounds from the gut should be decreased, whereas the f1 factor for soluble Pu compounds should be raised

  15. Micronutrient interactions: effects on absorption and bioavailability.

    Science.gov (United States)

    Sandström, B

    2001-05-01

    A potential risk of interactions between micronutrients affecting absorption and bioavailability has to be considered in any supplementation or fortification strategy. At levels of essential micronutrients present in foods, most micronutrients appear to utilise specific absorptive mechanisms and not be vulnerable to interactions. In aqueous solutions and at higher intake levels competition between elements with similar chemical characteristics and uptake by non-regulated processes can take place. These interactions have clearly been demonstrated in experimental absorption studies and to some extent have been confirmed in supplementation studies. Negative effects of iron supplementation on indices of zinc and copper status and of zinc supplementation on iron and copper status have been reported. In contrast, the negative effect of calcium on iron absorption has not been confirmed in long-term supplementation studies. Ascorbic acid has a strong iron absorption promoting potential and in iron deficient populations ascorbic acid supplementation improves iron status. Thus, ascorbic acid supplements or an increased intake of ascorbic acid rich foods could have important public health implications, especially in populations subsisting on a mainly plant food based diet. The effect of poor status of a given micronutrient on absorption and utilisation of other micronutrients should also be considered while developing strategies to improve micronutrient status in a population. Awareness of these interactions, combined with a balanced evaluation of the dietary intake of the population with regard to absorption promoting and inhibiting substances and the risk for multiple deficiencies, could lead to more effective strategies to improve micronutrient status.

  16. Threshold nonlinear absorption in Zeeman transitions

    International Nuclear Information System (INIS)

    Narayanan, Andal; Hazra, Abheera; Sandhya, S N

    2010-01-01

    We experimentally study the absorption spectroscopy from a collection of gaseous 87 Rb atoms at room temperature irradiated with three fields. Two of these fields are in a pump-probe saturation absorption configuration. The third field co-propagates with the pump field. The three fields address Zeeman degenerate transitions between hyperfine levels 5S 1/2 , F = 1 and 5P 3/2 , F = 0, F = 1 around the D2 line. We find a sub-natural absorption resonance in the counter-propagating probe field for equal detunings of all three fields. This absorption arises in conjunction with the appearance of increased transmission due to electro-magnetically induced transparency in the co-propagating fields. The novel feature of this absorption is its onset only for the blue of 5P 3/2 , F = 0, as the laser frequency is scanned through the excited states 5P 3/2 , F = 0, F = 1 and F = 2. The absorption rapidly rises to near maximum values within a narrow band of frequency near 5P 3/2 , F = 0. Our experimental results are compared with a dressed atom model. We find the threshold absorption to be a result of coherent interaction between the dressed states of our system.

  17. Sound Absorption Properties Of Single-Hole Hollow Polyester Fiber Reinforced Hydrogenated Carboxyl Nitrile Rubber Composites

    Directory of Open Access Journals (Sweden)

    Jie Hong

    2017-09-01

    Full Text Available A series of single-hole hollow polyester fiber (SHHPF reinforced hydrogenated carboxyl nitrile rubber (HXNBR composites were fabricated. In this study, the sound absorption property of the HXNBR/SHHPF composite was tested in an impedance tube, the composite morphology was characterized by scanning electron microscope (SEM, and the tensile mechanical property was measured by strength tester. The results demonstrated that a remarkable change in sound absorption can be observed by increasing the SHHPF content from 0% to 40%. In the composite with 40% SHHPF in 1 mm thickness, the sound absorption coefficient reached 0.671 at 2,500 Hz; the effective bandwidth was 1,800-2,500 Hz for sound absorption coefficient larger than 0.2. But the sound absorption property of the composite deteriorated when the SHHPF content increased to 50% in 1 mm thickness. While with 20% SHHPF proportion, the sound absorption property was improved by increasing the thickness of composites from 1 to 5 mm. Compared with the pure HXNBR of the same thickness, the tensile mechanical property of the composite improved significantly by increasing the SHHPF proportion. As a lightweight composite with excellent sound absorption property, the HXNBR/SHHPF composite has potential practical application value in the fields of engineering.

  18. 75 FR 65643 - Notice of Proposed Information Collection for Public Comment: Survey of Market Absorption of New...

    Science.gov (United States)

    2010-10-26

    ... Information Collection for Public Comment: Survey of Market Absorption of New Multifamily Units AGENCY: Office... required by the Paperwork Reduction Act of 1995. The Department is soliciting public comments on the... amended). I. Abstract: Description of the Need for the Information and Proposed Use The Survey of Market...

  19. Neural regulation of intestinal nutrient absorption.

    Science.gov (United States)

    Mourad, Fadi H; Saadé, Nayef E

    2011-10-01

    The nervous system and the gastrointestinal (GI) tract share several common features including reciprocal interconnections and several neurotransmitters and peptides known as gut peptides, neuropeptides or hormones. The processes of digestion, secretion of digestive enzymes and then absorption are regulated by the neuro-endocrine system. Luminal glucose enhances its own absorption through a neuronal reflex that involves capsaicin sensitive primary afferent (CSPA) fibres. Absorbed glucose stimulates insulin release that activates hepatoenteric neural pathways leading to an increase in the expression of glucose transporters. Adrenergic innervation increases glucose absorption through α1 and β receptors and decreases absorption through activation of α2 receptors. The vagus nerve plays an important role in the regulation of diurnal variation in transporter expression and in anticipation to food intake. Vagal CSPAs exert tonic inhibitory effects on amino acid absorption. It also plays an important role in the mediation of the inhibitory effect of intestinal amino acids on their own absorption at the level of proximal or distal segment. However, chronic extrinsic denervation leads to a decrease in intestinal amino acid absorption. Conversely, adrenergic agonists as well as activation of CSPA fibres enhance peptides uptake through the peptide transporter PEPT1. Finally, intestinal innervation plays a minimal role in the absorption of fat digestion products. Intestinal absorption of nutrients is a basic vital mechanism that depends essentially on the function of intestinal mucosa. However, intrinsic and extrinsic neural mechanisms that rely on several redundant loops are involved in immediate and long-term control of the outcome of intestinal function. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Force-detected nanoscale absorption spectroscopy in water at room temperature using an optical trap

    Science.gov (United States)

    Parobek, Alexander; Black, Jacob W.; Kamenetska, Maria; Ganim, Ziad

    2018-04-01

    Measuring absorption spectra of single molecules presents a fundamental challenge for standard transmission-based instruments because of the inherently low signal relative to the large background of the excitation source. Here we demonstrate a new approach for performing absorption spectroscopy in solution using a force measurement to read out optical excitation at the nanoscale. The photoinduced force between model chromophores and an optically trapped gold nanoshell has been measured in water at room temperature. This photoinduced force is characterized as a function of wavelength to yield the force spectrum, which is shown to be correlated to the absorption spectrum for four model systems. The instrument constructed for these measurements combines an optical tweezer with frequency domain absorption spectroscopy over the 400-800 nm range. These measurements provide proof-of-principle experiments for force-detected nanoscale spectroscopies that operate under ambient chemical conditions.

  1. Optoacoustic measurements of water vapor absorption at selected CO laser wavelengths in the 5-micron region

    Science.gov (United States)

    Menzies, R. T.; Shumate, M. S.

    1976-01-01

    Measurements of water vapor absorption were taken with a resonant optoacoustical detector (cylindrical pyrex detector, two BaF2 windows fitted into end plates at slight tilt to suppress Fabry-Perot resonances), for lack of confidence in existing spectral tabular data for the 5-7 micron region, as line shapes in the wing regions of water vapor lines are difficult to characterize. The measurements are required for air pollution studies using a CO laser, to find the differential absorption at the wavelengths in question due to atmospheric constituents other than water vapor. The design and performance of the optoacoustical detector are presented. Effects of absorption by ambient NO are considered, and the fixed-frequency discretely tunable CO laser is found suitable for monitoring urban NO concentrations in a fairly dry climate, using the water vapor absorption data obtained in the study.

  2. In vivo absorption spectra of the two stable states of the Euglena photoreceptor photocycle.

    Science.gov (United States)

    Barsanti, Laura; Coltelli, Primo; Evangelista, Valtere; Passarelli, Vincenzo; Frassanito, Anna Maria; Vesentini, Nicoletta; Santoro, Fabrizio; Gualtieri, Paolo

    2009-01-01

    Euglena gracilis possesses a simple but sophisticated light detecting system, consisting of an eyespot formed by carotenoids globules and a photoreceptor. The photoreceptor of Euglena is characterized by optical bistability, with two stable states. In order to provide important and discriminating information on the series of structural changes that Euglena photoreceptive protein(s) undergoes inside the photoreceptor in response to light, we measured the in vivo absorption spectra of the two stable states A and B of photoreceptor photocycle. Data were collected using two different devices, i.e. a microspectrophotometer and a digital microscope. Our results show that the photocycle and the absorption spectra of the photoreceptor possess strong spectroscopic similarities with a rhodopsin-like protein. Moreover, the analysis of the absorption spectra of the two stable states of the photoreceptor and the absorption spectrum of the eyespot suggests an intriguing hypothesis for the orientation of microalgae toward light.

  3. Long Wavelength Plasmonic Absorption Enhancement in Silicon Using Optical Lithography Compatible Core-Shell-Type Nanowires

    Directory of Open Access Journals (Sweden)

    Mohammed Shahriar Sabuktagin

    2014-01-01

    Full Text Available Plasmonic properties of rectangular core-shell type nanowires embedded in thin film silicon solar cell structure were characterized using FDTD simulations. Plasmon resonance of these nanowires showed tunability from  nm. However this absorption was significantly smaller than the Ohmic loss in the silver shell due to very low near-bandgap absorption properties of silicon. Prospect of improving enhanced absorption in silicon to Ohmic loss ratio by utilizing dual capability of these nanowires in boosting impurity photovoltaic effect and efficient extraction of the photogenerated carriers was discussed. Our results indicate that high volume fabrication capacity of optical lithography techniques can be utilized for plasmonic absorption enhancement in thin film silicon solar cells over the entire long wavelength range of solar radiation.

  4. Gas treating absorption theory and practice

    CERN Document Server

    Eimer, Dag

    2014-01-01

    Gas Treating: Absorption Theory and Practice provides an introduction to the treatment of natural gas, synthesis gas and flue gas, addressing why it is necessary and the challenges involved.  The book concentrates in particular on the absorption-desorption process and mass transfer coupled with chemical reaction. Following a general introduction to gas treatment, the chemistry of CO2, H2S and amine systems is described, and selected topics from physical chemistry with relevance to gas treating are presented. Thereafter the absorption process is discussed in detail, column hardware is explain

  5. Optical absorption in a thin nickel wire

    OpenAIRE

    INAGAKI, Takashi; Goudonnet, J.P.; ARAKAWA, E.T.

    1986-01-01

    Absorption of a 633-nm phonton in a cylindrical nickel wire with diameter 13 m was measured by a photoacoustic method as a function of angle of phonton incidence . A good photoacoustic signal was obtained with a 6-m W He-Ne laser as a light source without employing focusing optics. The absorption measured for p-polarized phontons was found to be in good agreement with geometrical optics calculation. For s-polarized light, however, significant excess absorption was found for >35.

  6. Optical absorption in irradiated natural beryl

    International Nuclear Information System (INIS)

    Isotani, S.; Dias, O.L.; Albuquerque, A.R.P.L.

    1983-10-01

    Three species of beryl irradiated with γ-rays of 60 Co were studied by optical absorption. One became yellow and the other two Maxixe's blue. The effects of heat treatments were determined by the thermal isochronal decays of the optical absorption bands. Activation energies and frequency factor were obtained through the first order process kinetic model. Discussions lend us to assign for the UV band-edge the model of absorption by a hole center stabilized by a Fe 2+ (substituting Al 3+ ) ion in a neighbour oxygen. (Author) [pt

  7. Gastrointestinal absorption of uranium in man

    International Nuclear Information System (INIS)

    Larsen, R.P.; Orlandini, K.A.

    1984-01-01

    A method has been established for determining the fractional absorption of uranium directly in man. Measurements are made of the urinary excretion rates of uranium for individuals whose drinking water has a high 234 U to 238 U activity ratio and is the primary source of 234 U in their diets. For two individuals, the values obtained for the fractional absorption of 234 U were 0.004 and 0.006. The values obtained for the fractional absorption of 238 U, using a literature value for the 238 U intake from food, were 0.008 and 0.015. The present ICRP value is 0.20. 7 references, 1 table

  8. Absorption of proteins and amino acids

    International Nuclear Information System (INIS)

    Jeejeebhoy, K.N.

    1976-01-01

    Although the absorption of proteins and amino acids is an important issue in nutrition, its measurement is not common because of the methodological difficulties. Complications are attributable in particular to the magnitude of endogenous protein secretion and to the diversity of absorption mechanisms for amino acids either as individual units or as peptides. Methods for studying absorption include balance techniques, tolerance tests, tracer techniques using proteins or amino acids labelled with 131 I, 3 H, or 15 N, intestinal perfusion studies, and others; they must be selected according to the nature of the information sought. Improvements over the current methods would be useful. (author)

  9. Sound absorption by a Helmholtz resonator

    Science.gov (United States)

    Komkin, A. I.; Mironov, M. A.; Bykov, A. I.

    2017-07-01

    Absorption characteristics of a Helmholtz resonator positioned at the end wall of a circular duct are considered. The absorption coefficient of the resonator is experimentally investigated as a function of the diameter and length of the resonator neck and the depth of the resonator cavity. Based on experimental data, the linear analytic model of a Helmholtz resonator is verified, and the results of verification are used to determine the dissipative attached length of the resonator neck so as to provide the agreement between experimental and calculated data. Dependences of sound absorption by a Helmholtz resonator on its geometric parameters are obtained.

  10. Absorption spectrum of Iodine around 5915 A

    International Nuclear Information System (INIS)

    1990-01-01

    The iodine absorption spectrum around 5915 A is of interest for many authors especially the hyperfine structure of the iodine line. Lodine absorption spectrum was obtained due to the interaction of iodine vapour with dye laser [(R6G) (0.5A) scanning range around 5915 A] which is pumped by(Ar + )laser absorption spectrum. The decrease in the peak of the transmission line around 5915 A shows the signal futher decreased by heating the iodine cell. This analysis has been done using a monochromator

  11. Saturable absorption in detonation nanodiamond dispersions

    Science.gov (United States)

    Vanyukov, Viatcheslav; Mikheev, Gennady; Mogileva, Tatyana; Puzyr, Alexey; Bondar, Vladimir; Lyashenko, Dmitry; Chuvilin, Andrey

    2017-07-01

    We report on a saturable absorption in aqueous dispersions of nanodiamonds with femtosecond laser pulse excitation at a wavelength of 795 nm. The open aperture Z-scan experiments reveal that in a wide range of nanodiamond particle sizes and concentrations, a light-induced increase of transmittance occurs. The transmittance increase originates from the saturation of light absorption and is associated with a light absorption at 1.5 eV by graphite and dimer chains (Pandey dimer chains). The obtained key nonlinear parameters of nanodiamond dispersions are compared with those of graphene and carbon nanotubes, which are widely used for the mode-locking.

  12. Biopharmaceutics classification and intestinal absorption study of apigenin.

    Science.gov (United States)

    Zhang, Jianjun; Liu, Dapeng; Huang, Yanting; Gao, Yuan; Qian, Shuai

    2012-10-15

    The aim of the study was to characterize the biopharmaceutics classification system (BCS) category of apigenin (AP) using intrinsic dissolution rate (IDR) and rat intestinal permeability, and to investigate the intestinal absorption mechanism of AP in rats. In the present investigation, equilibrium solubility and intrinsic dissolution rate (IDR) of AP were estimated in phosphate buffers. Effective intestinal permeability (P(eff)) of AP was determined using single-pass intestinal perfusion (SPIP) technique in four segments (duodenum, jejunum, ileum and colon) of rat intestine at three concentrations (10, 50 and 100 μg/ml). The aqueous solubility of AP in tested phosphate buffers was very poor with maximum solubility of 2.16 μg/ml at pH 7.5. The IDR of AP was very low with a value of 0.006 mg/min/cm(2). The minimum and maximum P(eff)s determined by SPIP were 0.198×10(-4) and 0.713×10(-4) cm/s at jejunum and duodenum site, respectively. In addition, the concentration-dependent permeability behavior was observed in the duodenum and jejunum, which suggested that AP was transported by both passive and active carrier-mediated saturable mechanism in these two intestinal segments. However, the observed concentration-independent permeability behavior in ileum and colon indicated primarily passive transport mechanism of absorption of AP in the last two intestinal segments. AP was classified as class II drug of the BCS due to its low solubility and high intestinal permeability. AP could be well absorbed in the whole intestine with the main absorption site at duodenum. The absorption of AP in four intestinal segments exhibited different transport mechanisms. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Continuum description for jointed media

    International Nuclear Information System (INIS)

    Thomas, R.K.

    1982-04-01

    A general three-dimensional continuum description is presented for a material containing regularly spaced and approximately parallel jointing planes within a representative elementary volume. Constitutive relationships are introduced for linear behavior of the base material and nonlinear normal and shear behavior across jointing planes. Furthermore, a fracture permeability tensor is calculated so that deformation induced alterations to the in-situ values can be measured. Examples for several strain-controlled loading paths are presented

  14. GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION.

    Energy Technology Data Exchange (ETDEWEB)

    PAQUETTE,D.E.; BENNETT,D.B.; DORSCH,W.R.; GOODE,G.A.; LEE,R.J.; KLAUS,K.; HOWE,R.F.; GEIGER,K.

    2002-05-31

    THE DEPARTMENT OF ENERGY ORDER 5400.1, GENERAL ENVIRONMENTAL PROTECTION PROGRAM, REQUIRES THE DEVELOPMENT AND IMPLEMENTATION OF A GROUNDWATER PROTECTION PROGRAM. THE BNL GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION PROVIDES AN OVERVIEW OF HOW THE LABORATORY ENSURES THAT PLANS FOR GROUNDWATER PROTECTION, MONITORING, AND RESTORATION ARE FULLY DEFINED, INTEGRATED, AND MANAGED IN A COST EFFECTIVE MANNER THAT IS CONSISTENT WITH FEDERAL, STATE, AND LOCAL REGULATIONS.

  15. Personality: Description, Classification and Evaluation

    Directory of Open Access Journals (Sweden)

    Ibrahim Taymur

    2012-06-01

    Full Text Available Many descriptions and classifications of personality have been made to understand and acknowledge human being through out the history. During the developmental process of psychiatry, almost every school defined and assessed personality regarding to their own perspective. As DSM (Diagnostical and Statistical Manual of Mental Disorders and ICD (International Classification of Diseases being available to common usage, scientists conducted studies to set a common terminology for personality. Categorical and dimensional approaches are the most fundamentally different assessment strategies in the research and clinical aspects about personality. While categorical approach views the personality as dichotomies which consists of different groups, dimensional approach aims to describe the personality on the basis of dimensions, thus suggests that the personality is a structure formed by definite dimensions. Several advantages and disadvantages can be noticed when descriptions of personality and tools for the evaluation of personality are reviewed. When the section making suggestions about personality disorder in DSM-5 is evaluated, it is seen that it aims to restructure the personality disorder diagnostic group according to new findings and critiques. In this article, the description of personality throughout the history, dimensional, categorical and cognitive approaches to personality, the features of the tools that are used to assess and measure the personality are reviewed.

  16. Description of fiction in Wikipedia

    Directory of Open Access Journals (Sweden)

    Alenka Šauperl

    2010-01-01

    Full Text Available Subject description of fiction in the Slovenian Cooperative On-line Bibliographic Database (COBIB is still inadequate. Participation in COBIB is granted to librarians who have successfully passed the exam. As a consequence, the number of contributing librarians is limited. However, all Slovenian librarians can collaborate in the Slovenian Wikipedia. Slovenian and foreign library science researchers have proposed the structure of subject description of fiction. An analysis of articles describing nine works of fiction in five wikipedias (English, French, Spanish, Croatian and Slovenian has shown new characteristics. Drawing on these findings, a suggestion of an optimal structure is made. An article describing a work of fiction should begin with a general introductory statement comprising the name of the author, his/her nationality and genre.Translators and original title should be written if a translation is presented. Illustrators and other contributors, the background and other specific information on the work should be added if relevant. The main body of the text should be structured in the following chapters: 1 contents, 2 collection, 3 reviews and awards, 4 editions and translations, 5 adaptations, 6 see also, 7 links and 8 sources. An "infobox: book" with Slovenian adaptation and relevant categories should be inserted. Copying these Wikipedia articles into the library catalogue would enhance subject description and provide better subject access to fiction.

  17. Absorption of manganese and iron in a mouse model of hemochromatosis.

    Directory of Open Access Journals (Sweden)

    Jonghan Kim

    Full Text Available Hereditary hemochromatosis, an iron overload disease associated with excessive intestinal iron absorption, is commonly caused by loss of HFE gene function. Both iron and manganese absorption are regulated by iron status, but the relationships between the transport pathways of these metals and how they are affected by HFE-associated hemochromatosis remain poorly understood. Loss of HFE function is known to alter the intestinal expression of DMT1 (divalent metal transporter-1 and Fpn (ferroportin, transporters that have been implicated in absorption of both iron and manganese. Although the influence of HFE deficiency on dietary iron absorption has been characterized, potential effects on manganese metabolism have yet to be explored. To investigate the role of HFE in manganese absorption, we characterized the uptake and distribution of the metal in Hfe (-/- knockout mice after intravenous, intragastric, and intranasal administration of (54Mn. These values were compared to intravenous and intragastric administration of (59Fe. Intestinal absorption of (59Fe was increased and clearance of injected (59Fe was also increased in Hfe(-/- mice compared to controls. Hfe (-/- mice displayed greater intestinal absorption of (54Mn compared to wild-type Hfe(+/+ control mice. After intravenous injection, the distribution of (59Fe to heart and liver was greater in Hfe (-/- mice but no remarkable differences were observed for (54Mn. Although olfactory absorption of (54Mn into blood was unchanged in Hfe (-/- mice, higher levels of intranasally-instilled (54Mn were associated with Hfe(-/- brain compared to controls. These results show that manganese transport and metabolism can be modified by HFE deficiency.

  18. Global sampling of the photochemical reaction paths of bromoform by ultrafast deep-UV through near-IR transient absorption and ab initio multiconfigurational calculations.

    Science.gov (United States)

    Pal, S K; Mereshchenko, A S; Butaeva, E V; El-Khoury, P Z; Tarnovsky, A N

    2013-03-28

    Ultrafast deep-ultraviolet through near infrared (210-950 nm) transient absorption spectroscopy complemented by ab initio multiconfigurational calculations offers a global description of the photochemical reaction pathways of bromoform following 255-nm excitation in methylcyclohexane and acetonitrile solutions. Photoexcitation of CHBr3 leads to the ground-state iso-CHBr3 product in a large quantum yield (∼35%), formed through two different mechanisms: concerted excited-state isomerization and cage-induced isomerization through the recombination of the nascent radical pair. These two processes take place on different time scales of tens of femtoseconds and several picoseconds, respectively. The novel ultrafast direct isomerization pathway proposed herein is consistent with the occurrence of a conical intersection between the first excited singlet state of CHBr3 and the ground electronic state of iso-CHBr3. Complete active space self-consistent field calculations characterize this singularity in the vicinity of a second order saddle point on the ground state which connects the two isomer forms. For cage-induced isomerization, both the formation of the nascent radical pair and its subsequent collapse into ground-state iso-CHBr3 are directly monitored through the deep-ultraviolet absorption signatures of the radical species. In both mechanisms, the optically active (i.e., those with largest Franck-Condon factors) C-Br-Br bending and Br-Br stretching modes of ground-state iso-CHBr3 have the largest projection on the reaction coordinate, enabling us to trace the structural changes accompanying vibrational relaxation of the non-equilibrated isomers through transient absorption dynamics. The iso-CHBr3 photoproduct is stable in methylcyclohexane, but undergoes either facile thermal isomerization to the parent CHBr3 structure through a cyclic transition state stabilized by the polar acetonitrile medium (∼300-ps lifetime), and hydrolysis in the presence of water.

  19. Gintonin absorption in intestinal model systems

    Directory of Open Access Journals (Sweden)

    Byung-Hwan Lee

    2018-01-01

    Conclusion: The present study shows that gintonin could be absorbed in the intestine through transcellular and paracellular diffusion, and active transport. In addition, the lipid component of gintonin might play a key role in its intestinal absorption.

  20. Electromagnetically induced absorption via incoherent collisions

    International Nuclear Information System (INIS)

    Yang Xihua; Sheng Jiteng; Xiao Min

    2011-01-01

    We conduct theoretical studies on electromagnetically induced absorption via incoherent collisions in an inhomogeneously broadened ladder-type three-level system with the density-matrix approach. The effects of the collision-induced coherence decay rates as well as the probe laser field intensity on the probe field absorption are examined. It is shown that with the increase of the collisional decay rates in a moderate range, a narrow dip due to electromagnetically induced transparency superimposed on the Doppler-broadened absorption background can be turned into a narrow peak under the conditions that the probe field intensity is not very weak as compared to the pump field, which results from the enhancement of constructive interference and suppression of destructive interference between one-photon and multiphoton transition pathways. The physical origin of the collision-assisted electromagnetically induced absorption is analyzed with a power-series solution of the density-matrix equations.

  1. Actinide absorption from the gastrointestinal tract

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1981-01-01

    A summary of our research is presented, describing the importance of the animal species, route of entry, oxidation state, solubility, and organic binding on the absorption of actinides from the gastrointestinal tract. The animal species tested made little difference in absorption, nor was the oxidation state a major factor in plutonium absorption under nonfasting conditions. The organic binding of actinides to either plant or animal tissues resulted in a 2- to 4-fold increase, except for 237 Np, which caused a 10-fold decrease. The age of the animals was the major influence on absorption. In all species studied, neonates absorbed more actinide than did the adults by two or three orders of magnitude. Retention of the actinide in the intestinal mucosa of rats and swine amounted to about half the dose of 238 Pu-nitrate administered; both after gavage and inhalation

  2. Unveiling the Microfoundations of Absorptive Capacity

    DEFF Research Database (Denmark)

    Distel, Andreas Philipp

    2017-01-01

    explores the multilevel antecedents of absorptive capacity using survey data gathered from 342 informants at different levels of analysis in 106 medical technology firms. Multilevel structural equation modeling analyses indicate that formal and informal integration mechanisms are positively related......Although the concept of absorptive capacity has gained wide acceptance in the literature, our understanding of the origins of a firm’s ability to absorb and leverage new knowledge is limited. Drawing on Coleman’s (1990) bathtub framework for macro-micro-macro-relations in social science, this study...... to absorptive capacity at the organizational level and that this relationship is mediated through a microlevel process. The findings reveal that knowledge workers’ cognitive process of perspective taking and their creative behavior are important microfoundations of absorptive capacity. Moreover, the results...

  3. The Driving Forces of Subsidiary Absorptive Capacity

    DEFF Research Database (Denmark)

    Schleimer, Stephanie C.; Pedersen, Torben

    2013-01-01

    The study investigates how a multinational corporation (MNC) can promote the absorptive capacity of its subsidiaries. The focus is on what drives the MNC subsidiary's ability to absorb marketing strategies that are initiated by the MNC parent, as well as how the subsidiary enacts on this absorptive...... capacity in order to compete in its focal market. The dual embeddedness of MNC subsidiaries plays a key role in this investigation, as subsidiaries belong to the MNC network and are simultaneously embedded in their host country environment. We argue that subsidiary absorptive capacity is formed...... as a purposeful response to this dual embeddedness. An analysis of marketing strategy absorptions undertaken by 213 subsidiaries reveals that MNCs can assist their subsidiaries to compete in competitive and dynamic focal markets by forming specific organizational mechanisms that are conducive to the development...

  4. Absorption chillers: Part of the solution

    International Nuclear Information System (INIS)

    Occhionero, A.J.; Hughes, P.J.; Reid, E.A.

    1991-01-01

    Acid rain, ozone depletion, global warming, and implementation economics are considered as they relate to the advisability of expanding the application of absorption chillers. Introductory and background information are provided to put the discussion in the proper context. Then all four issues are discussed separately as they relate to absorption chillers. Acid rain and ozone depletion concerns, and implementation economics, are found to support the expanded use of absorption chillers. The global warming concern is found to be more of a gray area, but the areas of benefit correspond well with the conditions of greatest economic advantage. All things considered, absorption chillers are believed to be part of the environmental and economic solution. It is further believed that integrated resource planning (IRP) processes that consider electric and gas technologies on an equal footing would come to the same conclusion for many regions of the United States. 9 refs., 3 tabs

  5. Differential Photoacoustic Particle Absorption Monitor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a highly sensitive and compact monitor to measure light absorption from particulate matters. The fundamental of the proposed device is based on...

  6. Performance Analysis of Solution Transportation Absorption Chiller

    Science.gov (United States)

    Kiani, Behdad; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    Thermally activated advanced absorption cycles are considered promising candidates to replace CFCs, HCFCs and HFCs for residential and commercial applications. In such absorption systems, it is desirable to utilize the waste heat from industries for heating and cooling applications in commercial and residential sectors. For this purpose, it is necessary to transport energy over some distance because the waste heat source and demand are generally located apart from each other. Transportation of steam, hot water or chilled water requires high construction costs for insulation. There is an efficient method of energy transportation using absorption system called “ Solution Transportation Absorption System (STA)”. The solution is transported at an ambient temperature so that tube-insulations not required. This paper shows the simulation of the abovementioned system and the optimal result, using mathematical optimization. The optimum system with industry‧s waste heat utilization is obtained. At the end, the effect on the pollution emission and energy conservation is obtained.

  7. Absorption boundary conditions for geomertical acoustics

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2012-01-01

    Defining accurate acoustical boundary conditions is of crucial importance for room acoustic simulations. In predicting sound fields using phased geometrical acoustics methods, the absorption coefficients or surface impedances of the boundary surfaces can be used, but no guideline has been developed...... on which boundary condition produces the best results. In this study, various boundary conditions in terms of normal and random incidence absorption coefficients, and normal incidence surface impedances are used in a phased beam tracing model, and simulated results are validated with boundary element...... solutions. Two rectangular rooms with uniform and non-uniform absorption distributions are tested. It is concluded that the impedance and random incidence absorption boundary conditions produce reasonable results with some exceptions at low frequencies for acoustically soft materials....

  8. Porosity and liquid absorption of cement paste

    DEFF Research Database (Denmark)

    Krus, M.; Hansen, Kurt Kielsgaard; Kunzel, H. M.

    1997-01-01

    are not accessible to the smaller helium atoms. Considering the results of dilatation tests both before and after water and hexane saturation, it seems possible that a contraction of capillary pores due to moisture-related swelling of the cement gel leads to the non-linear water absorption over the square root......The moisture behaviour of building materials exposed to the natural climate is largely dependent on their water absorption. In contrast to most building stones, cementitious materials like concrete do not exhibit a water absorption that is proportional to the square root of time. There must...... be a slowing-down effect which is related to water because the absorption of organic liquids, such as hexane, is quite normal. Measurements of the porosity of hardened cement paste determined by helium pycnometry and water saturation show that water molecules can enter spaces in the microstructure which...

  9. On pair-absorption in intrinsic vapours

    International Nuclear Information System (INIS)

    Hotop, R.; Niemax, K.; Schlueter, D.

    1982-01-01

    The bound-state pair-absorption bands Cs(6 2 S 1 sub(/) 2 ) + Cs(6 2 S 1 sub(/) 2 ) + hν → Cs(5 2 D 5 sub(/) 2 sub(,) 3 sub(/) 2 ) + Cs(6 2 P 1 sub(/) 2 ) and the K-K continuum-state pair-absorptions in the wavelength region 2.350 <= lambda <= 2.850 Angstroem have been investigated experimentally. In the case of the bound-state pair-absorption bands a theoretical approach for the absorption cross section at the band centre is given which is in good agreement with the experimental observation. Differences between our and the theoretical formulas given by the Stanford group are discussed. (orig.)

  10. Romania's road to Euro zone. From structural balance to structural balance corrected for absorption

    Directory of Open Access Journals (Sweden)

    Aura-Gabriela SOCOL

    2013-02-01

    Full Text Available The sovereign-debt crisis in the European Union has determined the necessity to reform the signal indicators for the analysis of the public finances' sustainability. In this context, many of the developing/emerging countries consider that the informational value provided by the structural budget balance indicator is insufficient, especially during the periods characterized by absorption. The present study suggests the transition from classical structural budget balance (CAB in the structural balance corrected for absorption (CAAB and supports the use of an improved indicator of the structural budget balance with a superior informational relevance for the macro-economic policies decision makers. Based on the economic literature we will demonstrate that the structural budget balance indicator should be improved, in order to also take into consideration the deviation of the current account balance from its sustainable level, particularly in the stage of the economic cycle characterized by high absorption.

  11. Emission and Absorption in the M87 LINER

    Science.gov (United States)

    Sabra, Bassem M.; Shields, Joseph C.; Ho, Luis C.; Barth, Aaron J.; Filippenko, Alexei V.

    2003-02-01

    The nucleus of M87 displays a LINER spectrum at optical wavelengths, with a nuclear disk of nebulosity that is resolved by the Hubble Space Telescope (HST). We present new results from optical and ultraviolet spectra of the central ~40 pc as measured by HST. In contrast with previous results for the extended disk, the emission-line spectrum of the central region is best reproduced by a multicomponent photoionization scenario, rather than shock heating. The nebular properties as well as energetic considerations suggest a transition on scales of several tens of parsecs, from predominantly photoionization by a central accretion source to shock ionization within the disk. If this source is at all representative, it suggests that many LINERs may be composite in terms of the energetic processes that give rise to the emission spectrum. We also report measurements of resonance-line absorption for the nucleus. The absorption spectrum, like the emission lines, is characterized by low ionization. The absorption-line measurements coupled with independent constraints suggest a total hydrogen column density of 1019-1020 cm-2, outflowing from the galaxy center with a velocity of ~126 km s-1. The kinematic signature of an outflow, along with evidence that the absorber covers the power-law continuum source but not the emission-line clouds, suggests that the absorbing matter is related to accretion phenomena in the nucleus. The presence of such an outflow resembles similar behavior in luminous active galactic nuclei, although the low ionization that characterizes LINERs is probably indicative of a different mode of accretion in these sources. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  12. Systemic Absorption of Nanomaterials by Oral Exposure

    DEFF Research Database (Denmark)

    Binderup, Mona-Lise; Bredsdorff, Lea; Beltoft, Vibe Meister

    This report and accompanying database systematically evaluates the reliability and relevance of the existing scientific literature regarding systemic absorption of nanomaterials by oral exposure and makes specific recommendations for future testing approaches.......This report and accompanying database systematically evaluates the reliability and relevance of the existing scientific literature regarding systemic absorption of nanomaterials by oral exposure and makes specific recommendations for future testing approaches....

  13. Determination of hafnium by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Yoshida, Isao; Kobayashi, Hiroshi; Ueno, Keihei.

    1977-01-01

    Optimum conditions for atomic absorption spectrophotometric determination of hafnium were investigated by use of a Jarrel-Ash AA-1 instrument which was equipped with a premixed gas burner slotted 50 mm in length and 0.4 mm in width. Absorption of hafnium, which was atomized in an nitrous oxide-acetylene flame, was measured on a resonance line at 307.29 nm. The absorption due to hafnium was enhanced in the presence of ammonium fluoride and iron(III) ion, as shown in Figs. 2 and 3, depending on their concentration. The highest absorption was attained by the addition of (0.15 -- 0.3)M ammonium fluoride, 0.07 M of iron(III) ion and 0.05 M of hydrochloric acid. An excess of the additives decreased the absorption. The presence of zirconium, which caused a significant interference in the ordinary analytical methods, did not affect the absorption due to hafnium, if the zirconium concentration is less than 0.2 M. A standard procedure was proposed; A sample containing a few mg of hafnium was dissolved in a 25-ml volumetric flask, and ammonium fluoride, ferric nitrate and hydrochloric acid were added so that the final concentrations were 0.3, 0.07 and 0.05 M, respectively. Atomic absorption was measured on the aqueous solution in a nitrous oxide-acetylene flame and the hafnium content was calculated from the absorbance. Sensitivity was as high as 12.5 μg of Hf/ml/l% absorption. The present method is especially recommendable to the direct determination of hafnium in samples containing zirconium. (auth.)

  14. Seasonal Solar Thermal Absorption Energy Storage Development.

    Science.gov (United States)

    Daguenet-Frick, Xavier; Gantenbein, Paul; Rommel, Mathias; Fumey, Benjamin; Weber, Robert; Gooneseker, Kanishka; Williamson, Tommy

    2015-01-01

    This article describes a thermochemical seasonal storage with emphasis on the development of a reaction zone for an absorption/desorption unit. The heat and mass exchanges are modelled and the design of a suitable reaction zone is explained. A tube bundle concept is retained for the heat and mass exchangers and the units are manufactured and commissioned. Furthermore, experimental results of both absorption and desorption processes are presented and the exchanged power is compared to the results of the simulations.

  15. Variations in the spectral values of specific absorption of phytoplankton

    Digital Repository Service at National Institute of Oceanography (India)

    Sathyendranath, S.; Lazzara, L; Prieur, L

    Absorption spectra of laboratory cultures of eight species of phytoplankton were studied. These spectra, normalized per unit of chlorophyll a concentration (specific absorption) show variability in magnitude and spectral form. Specific absorption...

  16. Vitamin D and intestinal calcium absorption.

    Science.gov (United States)

    Christakos, Sylvia; Dhawan, Puneet; Porta, Angela; Mady, Leila J; Seth, Tanya

    2011-12-05

    The principal function of vitamin D in calcium homeostasis is to increase calcium absorption from the intestine. Calcium is absorbed by both an active transcellular pathway, which is energy dependent, and by a passive paracellular pathway through tight junctions. 1,25Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) the hormonally active form of vitamin D, through its genomic actions, is the major stimulator of active intestinal calcium absorption which involves calcium influx, translocation of calcium through the interior of the enterocyte and basolateral extrusion of calcium by the intestinal plasma membrane pump. This article reviews recent studies that have challenged the traditional model of vitamin D mediated transcellular calcium absorption and the crucial role of specific calcium transport proteins in intestinal calcium absorption. There is also increasing evidence that 1,25(OH)(2)D(3) can enhance paracellular calcium diffusion. The influence of estrogen, prolactin, glucocorticoids and aging on intestinal calcium absorption and the role of the distal intestine in vitamin D mediated intestinal calcium absorption are also discussed. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Absorption Spectra of Gold Nanoparticle Suspensions

    Science.gov (United States)

    Anan'eva, M. V.; Nurmukhametov, D. R.; Zverev, A. S.; Nelyubina, N. V.; Zvekov, A. A.; Russakov, D. M.; Kalenskii, A. V.; Eremenko, A. N.

    2018-02-01

    Three gold nanoparticle suspensions are obtained, and mean radii in distributions - (6.1 ± 0.2), (11.9 ± 0.3), and (17.3 ± 0.7) nm - are determined by the transmission electron microscopy method. The optical absorption spectra of suspensions are obtained and studied. Calculation of spectral dependences of the absorption index of suspensions at values of the gold complex refractive index taken from the literature showed a significant deviation of experimental and calculated data in the region of 450-800 nm. Spectral dependences of the absorption of suspensions are simulated within the framework of the Mie-Drude theory taking into account the interband absorption in the form of an additional term in the imaginary part of the dielectric permittivity of the Gaussian type. It is shown that to quantify the spectral dependences in the region of the plasmon absorption band of nanoparticles, correction of the parameters of the interband absorption is necessary in addition to the increase of the relaxation parameter of the Drude theory. Spectral dependences of the dielectric permittivity of gold in nanodimensional state are refined from the solution of the inverse problem. The results of the present work are important for predicting the special features of operation of photonic devices and optical detonators based on gold nanoparticles.

  18. High temperature measurement of water vapor absorption

    Science.gov (United States)

    Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

    1985-01-01

    An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

  19. Ranking descriptive analysis in the sensory characterization of strawberry flavored diet yogurt enriched with whey protein concentrate / Análise descritiva por ordenação na caracterização sensorial de iogurte diet sabor morango enriquecido com concentrado protéico do soro

    Directory of Open Access Journals (Sweden)

    Luis Antonio Minim

    2010-09-01

    Full Text Available This study evaluated the sensory characteristics of diet strawberry flavored yogurt enriched with whey protein concentrate (WPC. Three formulations containing 0,5%, 1% and 1.5% of WPC (F2, F3 and F4 in order of increasing concentration and a controlled formulation without the addition of WCP (F1 were developed and evaluated by Ranking Descriptive Analysis. Twenty selected and trained panelists evaluated the samples characterized by attributes: pink color, viscosity, characteristic aroma of strawberry yogurt, characteristic flavor of strawberry yogurt, sweet taste, sour taste and consistency. The formulations differed significantly (p Este estudo avaliou as características sensoriais de iogurte diet sabor morango enriquecidos com concentrado protéico de soro (CPS. Três formulações contendo 0,5%, 1% e 1,5% de CPS (F2, F3 e F4 em ordem crescente de concentração e uma formulação controle sem adição de CPS (F1 foram desenvolvidas e avaliadas por meio da Análise Descritiva por Ordenação. Vinte provadores selecionados e treinados avaliaram as amostras caracterizadas pelos atributos: cor rosa, viscosidade, aroma característico de iogurte de morango, sabor característico de iogurte de morango, gosto doce, gosto ácido e consistência. As formulações diferiram significativamente (p < 0.05 nos atributos gosto doce e consistência. As amostras F3 e F4 apresentaram maior consistência confirmando a eficiência do CPS no aumento da consistência.

  20. Ultraviolet-visible absorptive features of water extractable and humic fractions of animal manure and compost

    Science.gov (United States)

    UV-vis spectroscopy is a useful tool for characterizing water extractable or humic fractions of natural organic matter (WEOM). Whereas the whole UV-visible spectra of these fractions are more or less featureless, the specific UV absorptivity at 254 and 280 nm as well as spectral E2/E3 and E4/E6 rat...

  1. Complexes of uranyl with N-oxides of heterocyclic amines. Electron-vibrational absorption spectra

    International Nuclear Information System (INIS)

    Jezowska-Trzebiatowska, B.; Wieczorek, M.

    1977-01-01

    A number of coordination compounds formed by uranyl chloride and nitrate with N-oxides of heterocyclic amines have been prepared and characterized by spectral measurements in the absorption region 20000-50000 cm -1 . The electrons and vibronic transitions have been determined and discussed. (author)

  2. Narrow CIV lambda 1549A Absorption Lines in Moderate-Redshift Quasars

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2002-01-01

    A large, high-quality spectral data base of well-selected, moderate-redshift radio-loud and radio-quiet quasars is used to characterize the incidence of narrow associated CIV lambda 1549 absorption, and how this may depend on some quasar properties, including radio-type. Preliminary results...

  3. Impact of aerosol heat radiation absorption on the dynamics of an atmospheric boundary layer in equilibrium

    NARCIS (Netherlands)

    Barbaro, E.W.; Vilà-Guerau de Arellano, J.; Krol, M.C.; Holtslag, A.A.M.

    2012-01-01

    The objective of this work is to investigate the influence of the shortwave radiation (SW) absorption by aerosols on the dynamics and heat budget of the atmospheric boundary layer (ABL). This study is relevant for areas characterized by large concentrations of light-absorbing aerosol, which are

  4. Redefining the Relationship between Intellectual Capital and Innovation: The Mediating Role of Absorptive Capacity

    Directory of Open Access Journals (Sweden)

    Alessandra Cassol

    2016-12-01

    Full Text Available The objective of this study is to analyze the relationship between absorptive capacity, intellectual capital and innovation. The main purpose of this research is to demonstrate that absorptive capacity can leverage the relation between intellectual capital and innovation potential. The method was a single case study using exploratory and descriptive research strategies and applying both quantitative and qualitative techniques. The case study investigated was a Brazilian corporation that has been doing business in the paper and corrugated cardboard industry for 72 years. The paper describes a case analysis demonstrating that adoption of practices associated with absorptive capacity has potential to foster intellectual capital, which is particularly important for development of innovations. These practices include assimilation of new technologies; creating capacity to utilize existing internal knowledge held by employees; use of benchmarking; application of technical knowledge; and registration of patents. Triangulation of data provided evidence confirming that the relationship between absorptive capacity and intellectual capital is a driver of innovation in the firm investigated. Additionally, this relationship is better explained by the mediating role of absorptive capacity, which is capable of potentiating intellectual capital to foster innovation.

  5. Single-photon absorption by single photosynthetic light-harvesting complexes

    Science.gov (United States)

    Chan, Herman C. H.; Gamel, Omar E.; Fleming, Graham R.; Whaley, K. Birgitta

    2018-03-01

    We provide a unified theoretical approach to the quantum dynamics of absorption of single photons and subsequent excitonic energy transfer in photosynthetic light-harvesting complexes. Our analysis combines a continuous mode -photon quantum optical master equation for the chromophoric system with the hierarchy of equations of motion describing excitonic dynamics in presence of non-Markovian coupling to vibrations of the chromophores and surrounding protein. We apply the approach to simulation of absorption of single-photon coherent states by pigment–protein complexes containing between one and seven chromophores, and compare with results obtained by excitation using a thermal radiation field. We show that the values of excitation probability obtained under single-photon absorption conditions can be consistently related to bulk absorption cross-sections. Analysis of the timescale and efficiency of single-photon absorption by light-harvesting systems within this full quantum description of pigment–protein dynamics coupled to a quantum radiation field reveals a non-trivial dependence of the excitation probability and the excited state dynamics induced by exciton–phonon coupling during and subsequent to the pulse, on the bandwidth of the incident photon pulse. For bandwidths equal to the spectral bandwidth of Chlorophyll a, our results yield an estimation of an average time of ∼0.09 s for a single chlorophyll chromophore to absorb the energy equivalent of one (single-polarization) photon under irradiation by single-photon states at the intensity of sunlight.

  6. Model parameterization to simulate and compare the PAR absorption potential of two competing plant species.

    Science.gov (United States)

    Bendix, Jörg; Silva, Brenner; Roos, Kristin; Göttlicher, Dietrich Otto; Rollenbeck, Rütger; Nauss, Thomas; Beck, Erwin

    2010-05-01

    Mountain pastures dominated by the pasture grass Setaria sphacelata in the Andes of southern Ecuador are heavily infested by southern bracken (Pteridium arachnoideum), a major problem for pasture management. Field observations suggest that bracken might outcompete the grass due to its competitive strength with regard to the absorption of photosynthetically active radiation (PAR). To understand the PAR absorption potential of both species, the aims of the current paper are to (1) parameterize a radiation scheme of a two-big-leaf model by deriving structural (LAI, leaf angle parameter) and optical (leaf albedo, transmittance) plant traits for average individuals from field surveys, (2) to initialize the properly parameterized radiation scheme with realistic global irradiation conditions of the Rio San Francisco Valley in the Andes of southern Ecuador, and (3) to compare the PAR absorption capabilities of both species under typical local weather conditions. Field data show that bracken reveals a slightly higher average leaf area index (LAI) and more horizontally oriented leaves in comparison to Setaria. Spectrometer measurements reveal that bracken and Setaria are characterized by a similar average leaf absorptance. Simulations with the average diurnal course of incoming solar radiation (1998-2005) and the mean leaf-sun geometry reveal that PAR absorption is fairly equal for both species. However, the comparison of typical clear and overcast days show that two parameters, (1) the relation of incoming diffuse and direct irradiance, and (2) the leaf-sun geometry play a major role for PAR absorption in the two-big-leaf approach: Under cloudy sky conditions (mainly diffuse irradiance), PAR absorption is slightly higher for Setaria while under clear sky conditions (mainly direct irradiance), the average bracken individual is characterized by a higher PAR absorption potential. (approximately 74 MJ m(-2) year(-1)). The latter situation which occurs if the maximum daily

  7. Subject categories and scope descriptions

    International Nuclear Information System (INIS)

    2002-01-01

    This document is one in a series of publications known as the ETDE/INIS Joint Reference Series. It defines the subject categories and provides the scope descriptions to be used for categorization of the nuclear literature for the preparation of INIS and ETDE input by national and regional centres. Together with the other volumes of the INIS Reference Series it defines the rules, standards and practices and provides the authorities to be used in the International Nuclear Information System and ETDE. A complete list of the volumes published in the INIS Reference Series may be found on the inside front cover of this publication. This INIS/ETDE Reference Series document is intended to serve two purposes: to define the subject scope of the International Nuclear Information System (INIS) and the Energy Technology Data Exchange (ETDE) and to define the subject classification scheme of INIS and ETDE. It is thus the guide to the inputting centres in determining which items of literature should be reported, and in determining where the full bibliographic entry and abstract of each item should be included in INIS or ETDE database. Each category is identified by a category code consisting of three alphanumeric characters. A scope description is given for each subject category. The scope of INIS is the sum of the scopes of all the categories. With most categories cross references are provided to other categories where appropriate. Cross references should be of assistance in finding the appropriate category; in fact, by indicating topics that are excluded from the category in question, the cross references help to clarify and define the scope of the category to which they are appended. A Subject Index is included as an aid to subject classifiers, but it is only an aid and not a means for subject classification. It facilitates the use of this document, but is no substitute for the description of the scope of the subject categories

  8. ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    M. Maniyar

    2004-06-22

    The purpose of this revision of the System Description Document (SDD) is to establish requirements that drive the design of the electrical power system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience are design engineers. This type of SDD leads and follows the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential to performing the design process. This SDD follows the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to this system are obtained from ''Project Functional and Operational Requirements'' (F&OR) (Siddoway, 2003). Other requirements to support the design process have been taken from higher level requirements documents such as ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), the fire hazards analyses, and the preclosure safety analysis. The above mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canori and Leitner 2003) requirements. This SDD includes several appendices with supporting information. Appendix B lists key system charts, diagrams, drawings, and lists; and Appendix C is a list of system procedures.

  9. ELECTRICAL SUPPORT SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    S. Roy

    2004-06-24

    The purpose of this revision of the System Design Description (SDD) is to establish requirements that drive the design of the electrical support system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience/users are design engineers. This type of SDD both ''leads'' and ''trails'' the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD trails the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to electrical support systems are obtained from the ''Project Functional and Operational Requirements'' (F&OR) (Siddoway 2003). Other requirements to support the design process have been taken from higher-level requirements documents such as the ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), and fire hazards analyses. The above-mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canon and Leitner 2003) requirements. This SDD contains several appendices that include supporting information. Appendix B lists key system charts, diagrams, drawings, and lists, and Appendix C includes a list of system procedures.

  10. SNF AGING SYSTEM DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    L.L. Swanson

    2005-01-01

    The purpose of this system description document (SDD) is to establish requirements that drive the design of the spent nuclear fuel (SNF) aging system and associated bases, which will allow the design effort to proceed. This SDD will be revised at strategic points as the design matures. This SDD identifies the requirements and describes the system design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This SDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This SDD is part of an iterative design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD follows the design with regard to the description of the system. The description provided in the SDD reflects the current results of the design process. Throughout this SDD, the term aging cask applies to vertical site-specific casks and to horizontal aging modules. The term overpack is a vertical site-specific cask that contains a dual-purpose canister (DPC) or a disposable canister. Functional and operational requirements applicable to this system were obtained from ''Project Functional and Operational Requirements'' (F andOR) (Curry 2004 [DIRS 170557]). Other requirements that support the design process were taken from documents such as ''Project Design Criteria Document'' (PDC) (BSC 2004 [DES 171599]), ''Site Fire Hazards Analyses'' (BSC 2005 [DIRS 172174]), and ''Nuclear Safety Design Bases for License Application'' (BSC 2005 [DIRS 171512]). The documents address requirements in the ''Project Requirements Document'' (PRD) (Canori and Leitner 2003 [DIRS 166275]). This SDD includes several appendices. Appendix A is a Glossary; Appendix B is a list of key system charts, diagrams, drawings, lists and additional supporting information; and Appendix C is a list of

  11. Calcium fortification of breakfast cereal enhances calcium absorption in children without affecting iron absorption.

    Science.gov (United States)

    Abrams, S A; Griffin, I J; Davila, P; Liang, L

    2001-10-01

    Provision of calcium-fortified foods may represent an important component of improving the calcium intake of children. We sought to determine whether the addition of calcium to cereal would have a net positive effect on calcium absorption without decreasing iron absorption. Twenty-seven children, 6 to 9 years of age, were provided two servings per day (30 g of cereal per serving) of either a low (39 mg/serving) or fortified (156 mg/serving) calcium-containing cereal product for 14 days. Calcium absorption was measured by using stable isotopes added to milk (extrinsically labeled) and to the calcium-fortified cereal (intrinsically labeled). Fractional calcium absorption from the fortified cereal was virtually identical to that from milk. Fractional absorption of calcium from milk did not differ significantly when given with enriched or low-calcium-containing cereal. Total calcium absorption increased from 215 +/- 45 mg/d to 269 +/- 45 mg/d with the addition of the calcium-fortified cereal (P Iron absorption was similar when children received the calcium-fortified cereal or unfortified cereal. The addition of a moderate amount of calcium to a cereal product was beneficial to calcium absorption and did not interfere with iron absorption. Use of calcium-fortified food products may be considered a practical approach to increasing the calcium intake of children.

  12. Polarization control of intermediate state absorption in resonance-mediated multi-photon absorption process

    International Nuclear Information System (INIS)

    Xu, Shuwu; Yao, Yunhua; Jia, Tianqing; Ding, Jingxin; Zhang, Shian; Sun, Zhenrong; Huang, Yunxia

    2015-01-01

    We theoretically and experimentally demonstrate the control of the intermediate state absorption in an (n + m) resonance-mediated multi-photon absorption process by the polarization-modulated femtosecond laser pulse. An analytical solution of the intermediate state absorption in a resonance-mediated multi-photon absorption process is obtained based on the time-dependent perturbation theory. Our theoretical results show that the control efficiency of the intermediate state absorption by the polarization modulation is independent of the laser intensity when the transition from the intermediate state to the final state is coupled by the single-photon absorption, but will be affected by the laser intensity when this transition is coupled by the non-resonant multi-photon absorption. These theoretical results are experimentally confirmed via a two-photon fluorescence control in (2 + 1) resonance-mediated three-photon absorption of Coumarin 480 dye and a single-photon fluorescence control in (1 + 2) resonance-mediated three-photon absorption of IR 125 dye. (paper)

  13. DESCRIPTIVE GRADES IN INITIAL MATHEMATICAL TEACHING PARENTS' ATTITUDES

    Directory of Open Access Journals (Sweden)

    Dževad Burgić

    2014-04-01

    Full Text Available Evaluation is very sensitive process in up bring-education work and it is important for comprehensive development of student. More often are fears of different kind, certain forms of unacceptable behavior, are connected with students failure in school and with school evaluation.Grade is feedback on achievements whose purpose is to provide timely information of current level and the steps that are ahead. Numerical grade reflects level of achievements, but there is no indication about elements that makes that grade. Descriptive grade contains key information's about the progress and for that kind of grade you need a lot of words. For student to be descriptively graded, teacher needs to be professionally educated and ready for detailed monitoring and evaluation of student's achievements. Teacher, using appropriate terminology, should successfully describe achievements of student's progress. The school is expected to teach students how to learn and to prepare them for lifelong learning. One of the important factors is also parents. During the time spent with teachers and parents a need has be shown to examine parent's attitudes about descriptive grades in nine-year elementary school. One of the courses that a descriptive grade cannot fully characterize the overall progress of students is mathematics. This course has been chosen because of the problems that parents have when their kids are in first two grades of nine-year elementary school, their attitudes about descriptive grades and difficulties they have when they try to understand student's achievements.

  14. DESCRIPTIVE GRADES IN INITIAL MATHEMATICAL TEACHING PARENT'S ATTITUDES

    Directory of Open Access Journals (Sweden)

    Dževad Burgić

    2014-04-01

    Full Text Available Evaluation is very sensitive process in up bring-education work and it is important for comprehensive development of student. More often are fears of different kind, certain forms of unacceptable behavior, are connected with students failure in school and with school evaluation.Grade is feedback on achievements whose purpose is to provide timely information of current level and the steps that are ahead. Numerical grade reflects level of achievements, but there is no indication about elements that makes that grade. Descriptive grade contains key information's about the progress and for that kind of grade you need a lot of words. For student to be descriptively graded, teacher needs to be professionally educated and ready for detailed monitoring and evaluation of student's achievements. Teacher, using appropriate terminology, should successfully describe achievements of student's progress. The school is expected to teach students how to learn and to prepare them for lifelong learning. One of the important factors is also parents. During the time spent with teachers and parents a need has be shown to examine parent's attitudes about descriptive grades in nine-year elementary school. One of the courses that a descriptive grade cannot fully characterize the overall progress of students is mathematics. This course has been chosen because of the problems that parents have when their kids are in first two grades of nine-year elementary school, their attitudes about descriptive grades and difficulties they have when they try to understand student's achievements.

  15. Monitored Geologic Repository Project Description Document

    Energy Technology Data Exchange (ETDEWEB)

    P. Curry

    2001-06-26

    The primary objective of the Monitored Geologic Repository Project Description Document (PDD) is to allocate the functions, requirements, and assumptions to the systems at Level 5 of the Civilian Radioactive Waste Management System (CRWMS) architecture identified in Section 4. It provides traceability of the requirements to those contained in Section 3 of the Yucca Mountain Site Characterization Project Requirements Document (YMP RD) (YMP 2001a) and other higher-level requirements documents. In addition, the PDD allocates design related assumptions to work products of non-design organizations. The document provides Monitored Geologic Repository (MGR) technical requirements in support of design and performance assessment in preparing for the Site Recommendation (SR) and License Application (LA) milestones. The technical requirements documented in the PDD are to be captured in the System Description Documents (SDDs) which address each of the systems at Level 5 of the CRWMS architecture. The design engineers obtain the technical requirements from the SDDs and by reference from the SDDs to the PDD. The design organizations and other organizations will obtain design related assumptions directly from the PDD. These organizations may establish additional assumptions for their individual activities, but such assumptions are not to conflict with the assumptions in the PDD. The PDD will serve as the primary link between the technical requirements captured in the SDDs and the design requirements captured in US Department of Energy (DOE) documents. The approved PDD is placed under Level 3 baseline control by the CRWMS Management and Operating Contractor (M&O) and the following portions of the PDD constitute the Technical Design Baseline for the MGR: the design characteristics listed in Table 1-1, the MGR Architecture (Section 4.1), the Technical Requirements (Section 5), and the Controlled Project Assumptions (Section 6).

  16. Thermodynamic description of liquid-state limits.

    Science.gov (United States)

    Woodcock, Leslie V

    2012-03-29

    A state of random close packing (RCP) of spheres is found to have a thermodynamic status and a fundamental role in the description of liquid-state equilibria. The RCP limiting amorphous ground state, with reproducible density and well-characterized structure, is obtained by well-defined irreversible and reversible processes. The limiting packing fraction y(RCP) = 0.6366 ± 0.0005 (Buffon's constant within the uncertainty), and a residual entropy per sphere ΔS((RCP-FCC)) is approximately equal to k(B) (Boltzmann's constant). Since the Mayer virial expansion does not represent dense fluid equations-of-state for densities exceeding the available-volume percolation transition (ρ(pa)), we infer that a RCP state belongs to the same thermodynamic phase as prepercolation equilibrium dense hard-sphere fluid and likewise for hard-core fluids with attractive forces. Monte Carlo (MC) calculation of the liquid-state coexistence properties of square-well (SW) attractive spheres, together with existing MC results for liquid-vapor coexistence in the SW fluid, support this conclusion. Further findings for liquid-vapor coexistence limits are reported. The extremely weak second-order available-volume percolation transition of the hard-sphere fluid is strengthened by square-well perturbation as temperature is reduced. At the critical temperature, this transition becomes first order, whereupon a liquid at the percolation density coexists in thermodynamic equilibrium with its vapor at a lower density. The critical coexisting vapor density relates to the extended-volume bonded cluster percolation transition ρ(pe)(λ) defined for given well width (λ). Taking experimental liquid argon data as an example, it can be seen that the thermodynamic description of the coexistence limits, found here for square-well fluids, applies to real liquids.

  17. The vegetation of Yucca Mountain: Description and ecology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-29

    Vegetation at Yucca Mountain, Nevada, was monitored over a six-year period, from 1989 through 1994. Yucca Mountain is located at the northern limit of the Mojave Desert and is the only location being studied as a potential repository for high-level nuclear waste. Site characterization consists of a series of multidisciplinary, scientific investigations designed to provide detailed information necessary to assess the suitability of the Yucca Mountain Site as a repository. This vegetation description establishes a baseline for determining the ecological impact of site characterization activities; it porvides input for site characterization research and modeling; and it clarifies vegetation community dynamics and relationships to the physical environment. A companion study will describe the impact of site characterization of vegetation. Cover, density, production, and species composition of vascular plants were monitored at 48 Ecological Study Plots (ESPs) stratified in four vegetation associations. Precipitation, soil moisture, and maximum and minimum temperatures also were measured at each study plot.

  18. The vegetation of Yucca Mountain: Description and ecology

    International Nuclear Information System (INIS)

    1996-01-01

    Vegetation at Yucca Mountain, Nevada, was monitored over a six-year period, from 1989 through 1994. Yucca Mountain is located at the northern limit of the Mojave Desert and is the only location being studied as a potential repository for high-level nuclear waste. Site characterization consists of a series of multidisciplinary, scientific investigations designed to provide detailed information necessary to assess the suitability of the Yucca Mountain Site as a repository. This vegetation description establishes a baseline for determining the ecological impact of site characterization activities; it porvides input for site characterization research and modeling; and it clarifies vegetation community dynamics and relationships to the physical environment. A companion study will describe the impact of site characterization of vegetation. Cover, density, production, and species composition of vascular plants were monitored at 48 Ecological Study Plots (ESPs) stratified in four vegetation associations. Precipitation, soil moisture, and maximum and minimum temperatures also were measured at each study plot

  19. Characterizing Black Hole Mergers

    Science.gov (United States)

    Baker, John; Boggs, William Darian; Kelly, Bernard

    2010-01-01

    Binary black hole mergers are a promising source of gravitational waves for interferometric gravitational wave detectors. Recent advances in numerical relativity have revealed the predictions of General Relativity for the strong burst of radiation generated in the final moments of binary coalescence. We explore features in the merger radiation which characterize the final moments of merger and ringdown. Interpreting the waveforms in terms of an rotating implicit radiation source allows a unified phenomenological description of the system from inspiral through ringdown. Common features in the waveforms allow quantitative description of the merger signal which may provide insights for observations large-mass black hole binaries.

  20. Polycapillary Optics Based Confocal Micro X-ray Fluorescence and X-ray Absorption Spectroscopy Setup at The European Synchrotron Radiation Facility Collaborative Research Group Dutch-Belgian Beamline, BM26A.

    Science.gov (United States)

    Bauters, Stephen; Tack, Pieter; Rudloff-Grund, Jennifer Helen; Banerjee, Dipanjan; Longo, Alessandro; Vekemans, Bart; Bras, Wim; Brenker, Frank E; van Silfhout, Roelof; Vincze, Laszlo

    2018-02-06

    A novel plug-and-play setup based on polycapillary X-ray optics enables three-dimensional (3D) confocal X-ray fluorescence (XRF) and X-ray absorption spectroscopy down to 8 × 8 × 11 μm 3 (17 keV) at the European Synchrotron Radiation Facility Collaborative Research Group Dutch-Belgian Beamline, BM26A. A complete description and analytical characterization is presented, together with two recently performed experimental cases. In Deep Earth diamond São Luiz-Frankfurt am Main 16, an olivine-rich inclusion was mapped with full 3D XRF elemental imaging. The preliminary tests on Iron Gall ink contained in an historical document, a letter from the court of King Philip II of Spain, reveal both the delicate nature of Iron Gall ink and the lack of Fe-Ni chemical bonding.

  1. Implanted Silicon Resistor Layers for Efficient Terahertz Absorption

    Science.gov (United States)

    Chervenak, J. A.; Abrahams, J.; Allen, C. A.; Benford, D. J.; Henry, R.; Stevenson, T.; Wollack, E.; Moseley, S. H.

    2005-01-01

    Broadband absorption structures are an essential component of large format bolometer arrays for imaging GHz and THz radiation. We have measured electrical and optical properties of implanted silicon resistor layers designed to be suitable for these absorbers. Implanted resistors offer a low-film-stress, buried absorber that is robust to longterm aging, temperature, and subsequent metals processing. Such an absorber layer is readily integrated with superconducting integrated circuits and standard micromachining as demonstrated by the SCUBA II array built by ROE/NIST (1). We present a complete characterization of these layers, demonstrating frequency regimes in which different recipes will be suitable for absorbers. Single layer thin film coatings have been demonstrated as effective absorbers at certain wavelengths including semimetal (2,3), thin metal (4), and patterned metal films (5,6). Astronomical instrument examples include the SHARC II instrument is imaging the submillimeter band using passivated Bi semimetal films and the HAWC instrument for SOFIA, which employs ultrathin metal films to span 1-3 THz. Patterned metal films on spiderweb bolometers have also been proposed for broadband detection. In each case, the absorber structure matches the impedance of free space for optimal absorption in the detector configuration (typically 157 Ohms per square for high absorption with a single or 377 Ohms per square in a resonant cavity or quarter wave backshort). Resonant structures with -20% bandwidth coupled to bolometers are also under development; stacks of such structures may take advantage of instruments imaging over a wide band. Each technique may enable effective absorbers in imagers. However, thin films tend to age, degrade or change during further processing, can be difficult to reproduce, and often exhibit an intrinsic granularity that creates complicated frequency dependence at THz frequencies. Thick metal films are more robust but the requirement for

  2. Addressing the Language Description Deficit

    Directory of Open Access Journals (Sweden)

    M. Ali Bolgiin

    2010-01-01

    Full Text Available Well-described language features are key to successful teaching and learning, especially for achieving advanced levels of proficiency. Other measures, such as simply increasing the number of reading and listening passages in a language program alone are not enough to bring the student to a higher level in a given skill. In fact, even being present in the target culture does not suffice. Angelelli and Degueldre (2002 argue that at advanced levels, even spending time in a country where the language is spoken is not necessarily sufficient for learners: "They do not need just exposure; they need answers to questions and explanations that they can rarely get by simply being immersed in a language/ culture." Less commonly taught languages (LCTLs lack descriptions that have such answers and explanations (cf. Fotos, 2002. It is argued in this paper that corpuslinguistic analyses help to provide actual usage-based, rather than intuition-based, descriptions and explanations of language features. Such approach is illustrated through English and Turkish examples.

  3. Integrated Project Management System description

    International Nuclear Information System (INIS)

    1994-09-01

    The Integrated Program Management System (IPMS) Description is a ''working'' document that describes the work processes of the Uranium Mill Tailings Remedial Action Project Office (UMTRA) and IPMS Group. This document has undergone many revisions since the UMTRA Project began; this revision not only updates the work processes but more clearly explains the relationships between the Project Office, contractors, and other participants. The work process flow style has been revised to better describe Project work and the relationships of participants. For each work process, more background and guidance on ''why'' and ''what is expected'' is given. For example, a description of activity data sheets has been added in the work organization and the Project performance and reporting processes, as well as additional detail about the federal budget process and funding management and improved flow charts and explanations of cost and schedule management. A chapter has been added describing the Cost Reduction/Productivity Improvement Program. The Change Control Board (CCB) procedures (Appendix A) have been updated. Project critical issues meeting (PCIM) procedures have been added as Appendix B. Budget risk assessment meeting procedures have been added as Appendix C. These appendices are written to act as stand-alone documentation for each process. As the procedures are improved and updated, the documentation can be updated separately

  4. Thermodynamical description of excited nuclei

    International Nuclear Information System (INIS)

    Bonche, P.

    1989-01-01

    In heavy ion collisions it has been possible to obtain composite systems at rather high excitation energies corresponding to temperatures of several MeV. The theoretical studies of these systems are based on concepts borrowed from thermodynamics or statistical physics, such as the temperature. In these lectures, we present the concepts of statistical physics which are involved in the physics of heavy ion as they are produced nowadays in the laboratory and also during the final stage of a supernova collapse. We do not attempt to describe the reaction mechanisms which yield such nuclear systems nor their decay by evaporation or fragmentation. We shall only study their static properties. The content of these lectures is organized in four main sections. The first one gives the basic features of statistical physics and thermodynamics necessary to understand quantum mechanics at finite temperature. In the second one, we present a study of the liquid-gas phase transition in nuclear physics. A phenomenological approach of the stability of hot nuclei follows. The microscopic point of view is proposed in the third part. Starting from the basic concepts derived in the first part, it provides a description of excited or hot nuclei which confirms the qualitative results of the second part. Furthermore it gives a full description of most properties of these nuclei as a function of temperature. Finally in the last part, a microscopic derivation of the equation of state of nuclear matter is proposed to study the collapse of a supernova core

  5. Archival Descriptions from the National Archives Catalog

    Data.gov (United States)

    National Archives and Records Administration — Archival Descriptions from the National Archives Catalog data set provides archival descriptions of the permanent holdings of the federal government in the custody...

  6. Iron absorption after antrectomy with gastroduodenostomy

    International Nuclear Information System (INIS)

    Magnusson, B.E.O.

    1976-01-01

    Haematological values were studied in 177 unselected patients 3-6 years after antrectomy with gastroduodenostomy. The majority (76%) had been operated upon for duodenal ulcer, 20% for gastric ulcer and the remaining patients had had both a duodenal and a gastric ulcer before the operation. In 65 patients a vagotomy had been added to the resection. 10% of the males and 15% of the females had a haemoglobin concentration below 13.0 or 12.0 g/100 ml, respectively. The corresponding frequencies for iron defifiency, defined as absence or only traces of haemosiderin in bone marrow smears, were 7% and 15%. The absorption of a small test dose of inorganic iron (0.56 mg Fe ++ as ferrous ascorbate) was studied in all the antrectomized patients. The absorption was also investigated in normal men and in patients who had had a Billroth II partial gastrectomy. No malabsorption of inorganic iron could be found in any of the groups. An inverse relationship between iron absorption and the grading of haemosiderin in bone marrow smears was found in normal subjects as well as in operated patients. Thus, an adequate increase of the absorption of ferrous iron was found even in operated patients with iron deficiency. Gastric acid secretion, measured as the peak acid output (PAO) after stimulation, was determined in all antrectomized patients. In patients having the same grading of haemosiderin (grade II) a slight but significant positive correlation was found between PAO and the absorption from the test dose (Fe ++ ). The absorption of food iron from a composite meal and the absorption from an iron salt (3.0 mg Fe ++ as ferrous ascorbate) was studied in 4 different groups: 1) normal males, 2) non-operated patients with peptic ulcer, 3) antrectomized patients with gastroduodenostomy and 4) patients operated upon with Billroth II partial gastrectomy. The range and mean absorption values from the test dose of inorganic iron were about the same in all groups. The absorption of food iron

  7. UV laser long-path absorption spectroscopy

    Science.gov (United States)

    Dorn, Hans-Peter; Brauers, Theo; Neuroth, Rudolf

    1994-01-01

    Long path Differential Optical Absorption Spectroscopy (DOAS) using a picosecond UV laser as a light source was developed in our institute. Tropospheric OH radicals are measured by their rotational absorption lines around 308 nm. The spectra are obtained using a high resolution spectrograph. The detection system has been improved over the formerly used optomechanical scanning device by application of a photodiode array which increased the observed spectral range by a factor of 6 and which utilizes the light much more effectively leading to a considerable reduction of the measurement time. This technique provides direct measurements of OH because the signal is given by the product of the absorption coefficient and the OH concentration along the light path according to Lambert-Beers law. No calibration is needed. Since the integrated absorption coefficient is well known the accuracy of the measurement essentially depends on the extent to which the OH absorption pattern can be detected in the spectra. No interference by self generated OH radicals in the detection lightpath has been observed. The large bandwidth (greater than 0.15 nm) and the high spectral resolution (1.5 pm) allows absolute determination of interferences by other trace gas absorptions. The measurement error is directly accessible from the absorption-signal to baseline-noise ratio in the spectra. The applicability of the method strongly depends on visibility. Elevated concentrations of aerosols lead to considerable attenuation of the laser light which reduces the S/N-ratio. In the moderately polluted air of Julich, where we performed a number of OH measurement spectra. In addition absorption features of unidentified species were frequently detected. A quantitative deconvolution even of the known species is not easy to achieve and can leave residual structures in the spectra. Thus interferences usually increase the noise and deteriorate the OH detection sensitivity. Using diode arrays for sensitive

  8. 3D Energy Absorption Diagram Construction of Paper Honeycomb Sandwich Panel

    Directory of Open Access Journals (Sweden)

    Dongmei Wang

    2018-01-01

    Full Text Available Paper honeycomb sandwich panel is an environment-sensitive material. Its cushioning property is closely related to its structural factors, the temperature and humidity, random shocks, and vibration events in the logistics environment. In order to visually characterize the cushioning property of paper honeycomb sandwich panel in different logistics conditions, the energy absorption equation of per unit volume of paper honeycomb sandwich panel was constructed by piecewise function. The three-dimensional (3D energy absorption diagram of paper honeycomb sandwich panel was constructed by connecting the inflexion of energy absorption curve. It takes into account the temperature, humidity, strain rate, and characteristics of the honeycomb structure. On the one hand, this diagram breaks through the limitation of the static compression curve of paper honeycomb sandwich panel, which depends on the test specimen and is applicable only to the standard condition. On the other hand, it breaks through the limitation of the conventional 2D energy absorption diagram which has less information. Elastic modulus was used to normalize the plateau stress and energy absorption per unit volume. This makes the 3D energy absorption diagram universal for different material sandwich panels. It provides a new theoretical basis for packaging optimized design.

  9. Dynamics of water absorption through superabsorbent polymer

    Science.gov (United States)

    Chang, Sooyoung; Kim, Wonjung

    2017-11-01

    Superabsorbent polymers (SAPs) consist of hydrophilic cross-linked polymer networks that can absorb and retain a great amount of water relative to their own mass, so that they are widely used for disposable diapers and holding soil moisture in agriculture. SAPs are typically available in the form of submillimeter-sized particles, and the water absorption is driven by capillary flows between particles as well as diffusion that entail swelling. Although the control of water absorption of SAPs is important in engineering applications, but the dynamics of water absorption in SAP particles has not been fully understood. We examine the dynamics of the water absorption of sodium polyacrylate, one of the most common SAP. We experimentally measured the water absorption of sodium polyacrylate particles in one-dimensional confined channel. The water flows through the particles were analyzed by capillarity dominant at the early stage and by diffusion involving volume expansion critical at a later stage. The results provide a quantitative basis of the hydrodynamic analysis of the water flow through SAP particles from a macroscopic point of view, facilitating the prediction of water uptake of SAPs in hygienic and agricultural applications. This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIP) (No.2015R1A2A2A04006181).

  10. Phytosterol glycosides reduce cholesterol absorption in humans.

    Science.gov (United States)

    Lin, Xiaobo; Ma, Lina; Racette, Susan B; Anderson Spearie, Catherine L; Ostlund, Richard E

    2009-04-01

    Dietary phytosterols inhibit intestinal cholesterol absorption and regulate whole body cholesterol excretion and balance. However, they are biochemically heterogeneous and a portion is glycosylated in some foods with unknown effects on biological activity. We tested the hypothesis that phytosterol glycosides reduce cholesterol absorption in humans. Phytosterol glycosides were extracted and purified from soy lecithin in a novel two-step process. Cholesterol absorption was measured in a series of three single-meal tests given at intervals of 2 wk to each of 11 healthy subjects. In a randomized crossover design, participants received approximately 300 mg of added phytosterols in the form of phytosterol glycosides or phytosterol esters, or placebo in a test breakfast also containing 30 mg cholesterol-d7. Cholesterol absorption was estimated by mass spectrometry of plasma cholesterol-d7 enrichment 4-5 days after each test. Compared with the placebo test, phytosterol glycosides reduced cholesterol absorption by 37.6+/-4.8% (Pphytosterol esters 30.6+/-3.9% (P=0.0001). These results suggest that natural phytosterol glycosides purified from lecithin are bioactive in humans and should be included in methods of phytosterol analysis and tables of food phytosterol content.

  11. Zinc absorption in inflammatory bowel disease

    International Nuclear Information System (INIS)

    Valberg, L.S.; Flanagan, P.R.; Kertesz, A.; Bondy, D.C.

    1986-01-01

    Zinc absorption was measured in 29 patients with inflammatory bowel disease and a wide spectrum of disease activity to determine its relationship to disease activity, general nutritional state, and zinc status. Patients with severe disease requiring either supplementary oral or parenteral nutrition were excluded. The mean 65ZnCl2 absorption, in the patients, determined using a 65Zn and 51Cr stool-counting test, 45 +/- 17% (SD), was significantly lower than the values, 54 +/- 16%, in 30 healthy controls, P less than 0.05. Low 65ZnCl2 absorption was related to undernutrition, but not to disease activity in the absence of undernutrition or to zinc status estimated by leukocyte zinc measurements. Mean plasma zinc or leukocyte zinc concentrations in patients did not differ significantly from controls, and only two patients with moderate disease had leukocyte zinc values below the 5th percentile of normal. In another group of nine patients with inflammatory bowel disease of mild-to-moderate severity and minimal nutritional impairment, 65Zn absorption from an extrinsically labeled turkey test meal was 31 +/- 10% compared to 33 +/- 7% in 17 healthy controls, P greater than 0.1. Thus, impairment in 65ZnCl2 absorption in the patients selected for this study was only evident in undernourished persons with moderate or severe disease activity, but biochemical evidence of zinc deficiency was uncommon, and clinical features of zinc depletion were not encountered

  12. Iron absorption from adequate Filipino meals

    International Nuclear Information System (INIS)

    Trinidad, T.P.; Madriaga, J.R.; Valdez, D.H.; Cruz, E.M.; Mallillin, A.C.; Sison, C.C.; Kuizon, M.D.

    1991-01-01

    Iron absorption from adequate Filipino meals representing the three major island groups of the Philippines (Luzon, Visayas and Mindanao) was studied using double isotope extrinsic tag method. Mean iron absorption of the one-day meal for Metro Manila was 6.6 ± 1.26%, Central Visayas, 6.3 ± 1.15% and Southern Mindanao, 6.4 ± 1.19%. Comparison between meals (breakfast, lunch, dinner) for each region as well as one-day meal for the three regions showed no significant differences (P > .01). Correlation tests done between iron absorption and the following iron enhancers: ascorbic acid, amount of fish, meat or poultry and inhibitors: phytic acid and tannic acid did not give significant results. The overall bar x of 6.4 ± 1.20% may be used as the non-heme iron absorption level from an adequate Filipino meal. This value can be considered as one of the bases for arriving at recommended dietary allowances for iron among Filipinos instead of the 10% iron absorption assumed in 1976

  13. Iron absorption from adequate Filipinos meals

    International Nuclear Information System (INIS)

    Trinidad, T.P.; Madriaga, J.R.; Valdez, D.H.; Cruz, E.M.; Mallillin, A.C.; Sison, C.C.; Kuizon, M.D.

    1989-01-01

    Iron absorption from adequate Filipino meals representing the three major island groups of the Philippines (Luzon, Visayas, and Mindanao) was studied using double isotope extrinsic tag method. Mean iron absorption of the one-day meal for Metro Manila was 6.6 +- 1.26%. Central Visayas, 6.3 +- 1.15% and Southern Mindanao, 6.4 +- 1.19%. Comparison between meals (breakfast, lunch, dinner) for each region as well as one-day meal for the three regions showed no significant differences (P>0.01). Correlation tests done between iron absorption and the following iron enhancers: ascorbic acid, amount of fish, meat or poultry; and inhibitors: phytic acid and tannic acid, did not give significant results. The overall average of 6.4 +- 1.20% may be used as the iron absorption level from an adequate Filipino meal. This value can be considered as one of the bases for arriving at recommended dietary allowances for iron among Filipinos instead of the 10% iron absorption assumed in 1976. (Auth.). 21 refs.; 3 tabs.; 3 annexes

  14. Biotin absorption by distal rat intestine

    International Nuclear Information System (INIS)

    Bowman, B.B.; Rosenberg, I.H.

    1987-01-01

    We used the in vivo intestinal loop approach, with short (10-min) and long (3-h) incubations, to examine biotin absorption in proximal jejunum, distal ileum, cecum and proximal colon. In short-term studies, luminal biotin disappearance from rat ileum was about half that observed in the jejunum, whereas absorption by proximal colon was about 12% of that in the jejunum. In 3-h closed-loop studies, the absorption of 1.0 microM biotin varied regionally. Biotin absorption was nearly complete in the small intestine after 3 h; however, only about 15% of the dose had been absorbed in the cecum and 27% in the proximal colon after 3 h. Independent of site of administration, the major fraction of absorbed biotin was recovered in the liver; measurable amounts of radioactive biotin were also present in kidney and plasma. The results support the potential nutritional significance for the rat of biotin synthesized by bacteria in the distal intestine, by demonstrating directly an absorptive capability of mammalian large bowel for this vitamin

  15. Identifying the perfect absorption of metamaterial absorbers

    Science.gov (United States)

    Duan, G.; Schalch, J.; Zhao, X.; Zhang, J.; Averitt, R. D.; Zhang, X.

    2018-01-01

    We present a detailed analysis of the conditions that result in unity absorption in metamaterial absorbers to guide the design and optimization of this important class of functional electromagnetic composites. Multilayer absorbers consisting of a metamaterial layer, dielectric spacer, and ground plane are specifically considered. Using interference theory, the dielectric spacer thickness and resonant frequency for unity absorption can be numerically determined from the functional dependence of the relative phase shift of the total reflection. Further, using transmission line theory in combination with interference theory we obtain analytical expressions for the unity absorption resonance frequency and corresponding spacer layer thickness in terms of the bare resonant frequency of the metamaterial layer and metallic and dielectric losses within the absorber structure. These simple expressions reveal a redshift of the unity absorption frequency with increasing loss that, in turn, necessitates an increase in the thickness of the dielectric spacer. The results of our analysis are experimentally confirmed by performing reflection-based terahertz time-domain spectroscopy on fabricated absorber structures covering a range of dielectric spacer thicknesses with careful control of the loss accomplished through water absorption in a semiporous polyimide dielectric spacer. Our findings can be widely applied to guide the design and optimization of the metamaterial absorbers and sensors.

  16. SNF AGING SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    L.L. Swanson

    2005-04-06

    The purpose of this system description document (SDD) is to establish requirements that drive the design of the spent nuclear fuel (SNF) aging system and associated bases, which will allow the design effort to proceed. This SDD will be revised at strategic points as the design matures. This SDD identifies the requirements and describes the system design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This SDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This SDD is part of an iterative design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD follows the design with regard to the description of the system. The description provided in the SDD reflects the current results of the design process. Throughout this SDD, the term aging cask applies to vertical site-specific casks and to horizontal aging modules. The term overpack is a vertical site-specific cask that contains a dual-purpose canister (DPC) or a disposable canister. Functional and operational requirements applicable to this system were obtained from ''Project Functional and Operational Requirements'' (F&OR) (Curry 2004 [DIRS 170557]). Other requirements that support the design process were taken from documents such as ''Project Design Criteria Document'' (PDC) (BSC 2004 [DES 171599]), ''Site Fire Hazards Analyses'' (BSC 2005 [DIRS 172174]), and ''Nuclear Safety Design Bases for License Application'' (BSC 2005 [DIRS 171512]). The documents address requirements in the ''Project Requirements Document'' (PRD) (Canori and Leitner 2003 [DIRS 166275]). This SDD includes several appendices. Appendix A is a Glossary; Appendix B is a list of key system charts

  17. The absorption of carbon monoxide in COSORB solutions: absorption rate and capacity

    NARCIS (Netherlands)

    Hogendoorn, Kees; van Swaaij, Willibrordus Petrus Maria; Versteeg, Geert

    1995-01-01

    Absorption rate experiments and equilibrium experiments were carried out for the COSORB reaction at 300 K. The equilibrium data at 300 K could reasonably well be described with the following relation: [...] Determination of the kinetics and mechanism of a chemical reaction by means of absorption

  18. Absorption lines, Faraday rotation, and magnetic field estimates for QSO absorption-line clouds

    International Nuclear Information System (INIS)

    Kronberg, P.P.; Perry, J.J.

    1982-01-01

    We have estimated the extragalactic component of Faraday rotation for a sample of 37 QSOs for which there is good absorption line data, which we have also analyzed. Statistical evidence is presented which suggests that we have isolated a component of Faraday rotation which is occurring in the absorption clouds of some QSOs

  19. Global warming description using Daisyworld model with greenhouse gases.

    Science.gov (United States)

    Paiva, Susana L D; Savi, Marcelo A; Viola, Flavio M; Leiroz, Albino J K

    2014-11-01

    Daisyworld is an archetypal model of the earth that is able to describe the global regulation that can emerge from the interaction between life and environment. This article proposes a model based on the original Daisyworld considering greenhouse gases emission and absorption, allowing the description of the global warming phenomenon. Global and local analyses are discussed evaluating the influence of greenhouse gases in the planet dynamics. Numerical simulations are carried out showing the general qualitative behavior of the Daisyworld for different scenarios that includes solar luminosity variations and greenhouse gases effect. Nonlinear dynamics perspective is of concern discussing a way that helps the comprehension of the global warming phenomenon. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Selective gas absorption by ionic liquids

    DEFF Research Database (Denmark)

    Shunmugavel, Saravanamurugan; Kegnæs, Søren; Due-Hansen, Johannes

    2010-01-01

    processes for flue gas cleaning. The results show that CO 2, NO and SO2 can be reversible and selective absorbed using different ILs and that Supported Ionic Liquid-Phase (SILP) absorbers are promising materials for industrial flue gas cleaning. Absorption/desorption dynamics can be tuned by temperatures......Reversible absorption performance for the flue gas components CO 2, NO and SO2 has been tested for several different ionic liquids (ILs) at different temperatures and flue gas compositions. Furthermore, different porous, high surface area carriers have been applied as supports for the ionic liquids...... to obtain Supported Ionic Liquid-Phase (SILP) absorber materials. The use of solid SILP absorbers with selected ILs were found to significantly improve the absorption capacity and sorption dynamics at low flue gas concentration, thus making the applicability of ILs viable in technical, continuous flow...

  1. Time-resolved absorption measurements on OMEGA

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; DaSilva, L.; Delettrez, J.; Gregory, G.G.; Richardson, M.C.

    1986-01-01

    Time-resolved measurements of the incident laser light that is scattered and/or refracted from targets irradiated by the 24 uv-beam OMEGA laser at LLE, have provided some interesting features related to time-resolved absorption. The decrease in laser absorption characteristic of irradiating a target that implodes during the laser pulse has been observed. The increase in absorption expected as the critical density surface moves from a low to a high Z material in the target has also been noted. The detailed interpretation of these results is made through comparisons with simulation using the code LILAC, as well as with streak data from time-resolved x-ray imaging and spectroscopy. In addition, time and space-resolved imaging of the scattered light yields information on laser irradiation uniformity conditions on the target. The report consists of viewgraphs

  2. Plasmon absorption modulator systems and methods

    Science.gov (United States)

    Kekatpure, Rohan Deodatta; Davids, Paul

    2014-07-15

    Plasmon absorption modulator systems and methods are disclosed. A plasmon absorption modulator system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and a metal layer formed on a top surface of the stack of quantum well layers. A method for modulating plasmonic current includes enabling propagation of the plasmonic current along a metal layer, and applying a voltage across the stack of quantum well layers to cause absorption of a portion of energy of the plasmonic current by the stack of quantum well layers. A metamaterial switching system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and at least one metamaterial structure formed on a top surface of the stack of quantum well layers.

  3. Intestinal absorption of specific structured triacylglycerols

    DEFF Research Database (Denmark)

    Mu, Huiling; Høy, Carl-Erik

    2001-01-01

    -sn-glycerol (10:0/18:2/10:0), and 1,3-didodecanoyl-2-linoleoyl-sn-glycerol (12:0/18:2/12:0) in a rat model. Safflower oil was used in the absorption study in order to compare the absorption of medium- chain fatty acids and long-chain fatty acids, The triacylglycerol species of lymph Lipids were separated......-type triacylglycerols. From the present study we conclude that the medium-chain fatty acids from STAG, in addition to absorption into the portal blood as free fatty acids, are absorbed by the same pathway as the conventional long-chain triacylglycerols, that is, they are hydrolyzed into free fatty acids, absorbed...

  4. Ultrafast Coherent Absorption in Diamond Metamaterials.

    Science.gov (United States)

    Karvounis, Artemios; Nalla, Venkatram; MacDonald, Kevin F; Zheludev, Nikolay I

    2018-02-27

    Diamond is introduced as a material platform for visible/near-infrared photonic metamaterials, with a nanostructured polycrystalline diamond metasurface only 170 nm thick providing an experimental demonstration of coherent light-by-light modulation at few-optical-cycle (6 fs) pulse durations. "Coherent control" of absorption in planar (subwavelength-thickness) materials has emerged recently as a mechanism for high-contrast all-optical gating, with a speed of response that is limited only by the spectral width of the absorption line. It is shown here that a free-standing diamond membrane structured by focused ion beam milling can provide strong, spectrally near-flat absorption over a visible to near-infrared wavelength range that is wide enough (wider than is characteristically achievable in plasmonic metal metasurfaces) to facilitate coherent modulation of ultrashort optical pulses comprising only a few oscillations of electromagnetic field. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Absorption of carbon dioxide in waste tanks

    International Nuclear Information System (INIS)

    Hobbs, D.T.

    1987-01-01

    Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution

  6. Tunable electromagnetically induced absorption based on graphene

    Science.gov (United States)

    Cao, Maoyong; Wang, Tongling; Zhang, Huiyun; Zhang, Yuping

    2018-04-01

    In this paper, an electronically induced absorption (EIA) structure based on graphene at the infrared frequency is proposed. A pair of nanorods is coupled to a ring resonator, resulting in electronically induced transparency (EIT), and then, Babinet's principle is applied to transform the EIT structure into an EIA structure. Based on the bright and dark modes of the coupling schemes, the adjustment of the coupling strength between the dark and bright modes can be achieved by changing the asymmetry degree. In addition, the transparency window and the absorption peak can be tuned by changing the Fermi energy of graphene. This graphene-based EIA structure can develop the path in narrow-band filtering and, absorptive switching in the future.

  7. A Review: Characteristics of Noise Absorption Material

    Science.gov (United States)

    Amares, S.; Sujatmika, E.; Hong, T. W.; Durairaj, R.; Hamid, H. S. H. B.

    2017-10-01

    Noise is always treated as a nuisance to human and even noise pollution appears in the environmental causing discomfort. This also concerns the engineering design that tends to cultivate this noise propagation. Solution such as using material to absorb the sound have been widely used. The fundamental of the sound absorbing propagation, sound absorbing characteristics and its factors are minimally debated. Furthermore, the method in order to pertain sound absorbing related to the sound absorption coefficient is also limited, as many studies only contributes in result basis and very little in literature aspect. This paper revolves in providing better insight on the importance of sound absorption and the materials factors in obtaining the sound absorption coefficient.

  8. Gold analysis by the gamma absorption technique

    International Nuclear Information System (INIS)

    Kurtoglu, Arzu; Tugrul, A.B.

    2003-01-01

    Gold (Au) analyses are generally performed using destructive techniques. In this study, the Gamma Absorption Technique has been employed for gold analysis. A series of different gold alloys of known gold content were analysed and a calibration curve was obtained. This curve was then used for the analysis of unknown samples. Gold analyses can be made non-destructively, easily and quickly by the gamma absorption technique. The mass attenuation coefficients of the alloys were measured around the K-shell absorption edge of Au. Theoretical mass attenuation coefficient values were obtained using the WinXCom program and comparison of the experimental results with the theoretical values showed generally good and acceptable agreement

  9. Absorption spectra of AA-stacked graphite

    International Nuclear Information System (INIS)

    Chiu, C W; Lee, S H; Chen, S C; Lin, M F; Shyu, F L

    2010-01-01

    AA-stacked graphite shows strong anisotropy in geometric structures and velocity matrix elements. However, the absorption spectra are isotropic for the polarization vector on the graphene plane. The spectra exhibit one prominent plateau at middle energy and one shoulder structure at lower energy. These structures directly reflect the unique geometric and band structures and provide sufficient information for experimental fitting of the intralayer and interlayer atomic interactions. On the other hand, monolayer graphene shows a sharp absorption peak but no shoulder structure; AA-stacked bilayer graphene has two absorption peaks at middle energy and abruptly vanishes at lower energy. Furthermore, the isotropic features are expected to exist in other graphene-related systems. The calculated results and the predicted atomic interactions could be verified by optical measurements.

  10. Review on absorption technology with emphasis on small capacity absorption machines

    Directory of Open Access Journals (Sweden)

    Labus Jerko M.

    2013-01-01

    Full Text Available The aim of this paper is to review the past achievements in the field of absorption systems, their potential and possible directions for future development. Various types of absorption systems and research on working fluids are discussed in detail. Among various applications, solar cooling and combined cooling, heating and power (CCHP are identified as two most promising applications for further development of absorption machines. Under the same framework, special attention is given to the small capacity absorption machines and their current status at the market. Although this technology looks promising, it is still in development and many issues are open. With respect to that fact, this paper covers all the relevant aspects for further development of small capacity absorption machines.

  11. Theory buried under heavy description

    Directory of Open Access Journals (Sweden)

    Vivian B. Martin Ph.D.

    2010-12-01

    Full Text Available In journalism when a reporter puts the main news or point of the story deep down in the text, we say she’s buried the lead, the lead being the main point of the story and usually the first paragraph. In Children in Genocide: extreme traumatization and affect regulation, psychoanalyst Suzanne Kaplan buries her theory. Her study of the after effects of trauma among Holocaust survivors who were children during their persecution and survivors of atrocities during the Rwandan atrocities of the 1990s, is filled with highly descriptive material from the many interviews that serve as data. An interesting grounded theory is peeking out from under all the disciplinary discourse and historical background one must read through to get to what grounded theory readers will consider the juicy parts: concepts on affect regulation in trauma survivors.

  12. Integrated Project Management System description

    International Nuclear Information System (INIS)

    1987-03-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project is a Department of Energy (DOE) designated Major System Acquisition (MSA). To execute and manage the Project mission successfully and to comply with the MSA requirements, the UMTRA Project Office (''Project Office'') has implemented and operates an Integrated Project Management System (IPMS). The Project Office is assisted by the Technical Assistance Contractor's (TAC) Project Integration and Control (PIC) Group in system operation. Each participant, in turn, provides critical input to system operation and reporting requirements. The IPMS provides a uniform structured approach for integrating the work of Project participants. It serves as a tool for planning and control, workload management, performance measurement, and specialized reporting within a standardized format. This system description presents the guidance for its operation. Appendices 1 and 2 contain definitions of commonly used terms and abbreviations and acronyms, respectively. 17 figs., 5 tabs

  13. Reversible gates and circuits descriptions

    Science.gov (United States)

    Gracki, Krzystof

    2017-08-01

    This paper presents basic methods of reversible circuit description. To design reversible circuit a set of gates has to be chosen. Most popular libraries are composed of three types of gates so called CNT gates (Control, NOT and Toffoli). The gate indexing method presented in this paper is based on the CNT gates set. It introduces a uniform indexing of the gates used during synthesis process of reversible circuits. The paper is organized as follows. Section 1 recalls basic concepts of reversible logic. In Section 2 and 3 a graphical representation of the reversible gates and circuits is described. Section 4 describes proposed uniform NCT gates indexing. The presented gate indexing method provides gate numbering scheme independent of lines number of the designed circuit. The solution for a circuit consisting of smaller number of lines is a subset of solution for a larger circuit.

  14. Relativistic description of deformed nuclei

    International Nuclear Information System (INIS)

    Price, C.E.

    1988-01-01

    The author has shown that relativistic Hartree calculations using parameters that have been fit to the properties of nuclear matter can provide a good description of both spherical and axially deformed nuclei. The quantitative agreement with experiment is equivalent to that which was obtained in non-relativistic calculations using Skyrme interactions. The equilibrium deformation is strongly correlated with the size of the spin-orbit splitting, and that parameter sets which give roughly the correct value for this splitting provide the best agreement with the quadrupole moments in the s-d shell. Finally, for closed shell +/- 1 nuclei, it was shown that the self-consistent calculations are able to reproduce the experimental magnetic moments. This was not possible in relativistic calculations which include only the effects of the valence orbital

  15. Infrared Absorption by Atmospheric Aerosols in Mexico City during MILAGRO.

    Science.gov (United States)

    Kelley, K. L.; Mangu, A.; Gaffney, J. S.; Marley, N. A.

    2007-12-01

    Past research in our group using cylindrical internal reflectance spectroscopy has indicated that aqueous aerosols could contribute to the radiative warming as greenhouse species (1,2). Although aerosol radiative effects have been known for sometime and are considered one of the major uncertainties in climate change modeling, most of the studies have focused on the forcing due to scattering and absorption of radiation in the uv- visible region (3). Infrared spectral information also allows the confirmation of key functional groups that are responsible for enhanced absorption observations from secondary organics in the uv-visible region. This work extends our efforts to evaluate the infrared absorption by aerosols, particularly organics, that are now found to be a major fraction of urban and regional aerosols in the 0.1 to 1.0 micron size range and to help identify key types of organics that can contribute to aerosol absorption. During the MILAGRO campaign, quartz filter samples were taken at 12-hour intervals from 5 am to 5 pm (day) and from 5 pm to 5 am (night) during the month of March 2006. These samples were taken at the two super-sites, T-0 (Instituto Mexicano de Petroleo in Mexico City) and T-1 (Universidad Technologica de Tecamac, State of Mexico). The samples have been characterized for total carbon content (stable isotope mass spectroscopy) and natural radionuclide tracers, as well as for their UV-visible spectroscopic properties by using integrating sphere diffuse reflectance spectroscopy (Beckman DU with a Labsphere accessory). These same samples have been characterized in the mid and near infrared spectral ranges using diffuse reflection spectroscopy (Nicolet 6700 FTIR with a Smart Collector accessory). Aerosol samples were removed from the surfaces of the aerosol filters by using Si-Carb sampler. The samples clearly indicate the presence of carbonyl organic constituents and the spectra are quite similar to those observed for humic and fulvic acids

  16. Particulate absorption properties in the Red Sea from hyperspectral particulate absorption spectra

    KAUST Repository

    Tiwari, Surya Prakash

    2018-03-16

    This paper aims to describe the variability of particulate absorption properties using a unique hyperspectral dataset collected in the Red Sea as part of the TARA Oceans expedition. The absorption contributions by phytoplankton (aph) and non-algal particles (aNAP) to the total particulate absorption coefficients are determined using a numerical decomposition method (NDM). The NDM is validated by comparing the NDM derived values of aph and aNAP with simulated values of aph and aNAP are found to be in excellent agreement for the selected wavelengths (i.e., 443, 490, 555, and 676nm) with high correlation coefficient (R2), low root mean square error (RMSE), mean relative error (MRE), and with a slope close to unity. Further analyses showed that the total particulate absorption coefficients (i.e., ap(443)average = 0.01995m−1) were dominated by phytoplankton absorption (i.e., aph(443)average = 0.01743m−1) with a smaller contribution by non-algal particles absorption (i.e., aNAP(443)average = 0.002524m−1). The chlorophyll a is computed using the absorption based Line Height Method (LHM). The derived chlorophyll-specific absorption ((a⁎ph = aph(λ)/ChlLH)) showed more variability in the blue part of spectrum as compared to the red part of spectrum representative of the package effect and changes in pigment composition. A new parametrization proposed also enabled the reconstruction of a⁎ph(λ) for the Red Sea. Comparison of derived spectral constants with the spectral constants of existing models showed that our study A(λ) values are consistent with the existing values, despite there is a divergence with the B(λ) values. This study provides valuable information derived from the particulate absorption properties and its spectral variability and this would help us to determine the relationship between the phytoplankton absorption coefficients and chlorophyll a and its host of variables for the Red Sea.

  17. XUV Absorption by Solid Density Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, C A

    2009-09-21

    An inverse bremsstrahlung model for plasmas and simple metals that approximates the cold, solid Al experimental data below the L-edge is applied to matter conditions relevant to XUV laser applications. The model involves an all-order calculation using a semi-analytical effective electron-ion interaction. The predicted increases in XUV absorption with rising temperature occur via two effects: increased availability of final states from reduced electron degeneracy and a stronger electron-ion interaction from reduced screening. Discrepancies in the temperature dependence as well as other details between the present approach and a recently proposed absorption model are discussed.

  18. Extending Organizational Antecedents Of Absorptive Capacity

    DEFF Research Database (Denmark)

    Burcharth, Ana Luiza de Araújo; Lettl, Christopher; Ulhøi, John Parm

    2015-01-01

    on multi-informant survey data collected from SMEs in Denmark (n=169), we find empirical support for the impact of these characteristics (except for tolerance for failure) on various aspects of absorptive capacity (both potential and realized). Before concluding, we discuss the theoretical and managerial......Absorptive capacity has generally been perceived as a ‘passive’ outcome of R&D investments. Recently, however, a renewed debate on its ‘proactive’ dimensions has emerged. We tap into this development and complement the existing discussion on combinative capabilities with a perspective that focuses...

  19. Achromatic THz absorption of conductive nanofilms

    Directory of Open Access Journals (Sweden)

    Qiang Yin

    2015-10-01

    Full Text Available According to the theory, an ultrathin conductive film can achromatically dissipate electromagnetic waves with frequency ranging from radio to terahertz. A moderate absorption effect, which gives rise to a maximal absorbance of 50%, can be found if an impedance matching condition is satisfied. We have experimentally demonstrated the frequency-irrelevant, maximal absorption by employing a conductive nanofilm and launching terahertz waves at Brewster angle when the sheet (square resistance of the film meets the impedance matching condition. In the entire terahertz spectral range covered by our experiments, the frequency-independent optical properties were consistent with the theoretical calculations.

  20. Laser isotope separation by multiple photon absorption

    Science.gov (United States)

    Robinson, C.P.; Rockwood, S.D.; Jensen, R.J.; Lyman, J.L.; Aldridge, J.P. III.

    1987-04-07

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, is the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO[sub 2] laser light may be used to highly enrich [sup 34]S in natural SF[sub 6] and [sup 11]B in natural BCl[sub 3]. 8 figs.

  1. Monitoring of MOCVD reactants by UV absorption

    Energy Technology Data Exchange (ETDEWEB)

    Baucom, K.C.; Killeen, K.P.; Moffat, H.K.

    1995-07-01

    In this paper, we describe how UV absorption measurements can be used to measure the flow rates of metal organic chemical vapor deposition (MOCVD) reactants. This method utilizes the calculation of UV extinction coefficients by measuring the total pressure and absorbance in the neat reactant system. The development of this quantitative reactant flow rate monitor allows for the direct measurement of the efficiency of a reactant bubbler. We demonstrate bubbler efficiency results for TMGa, and then explain some discrepancies found in the TMAl system due to the monomer to dimer equilibrium. Also, the UV absorption spectra of metal organic and hydride MOCVD reactants over the wavelength range 185 to 400 nm are reported.

  2. Theory of attosecond absorption spectroscopy in krypton

    DEFF Research Database (Denmark)

    Baggesen, Jan Conrad; Lindroth, Eva; Madsen, Lars Bojer

    2012-01-01

    A theory for time-domain attosecond pump–attosecond probe photoabsorption spectroscopy is formulated and related to the atomic response. The theory is illustrated through a study of attosecond absorption spectroscopy in krypton. The atomic parameters entering the formulation such as energies...... of the hole in this manner. In a second example, a hole is created in an inner shell by the first pulse, and the second probe pulse couples an even more tightly bound state to that hole. The hole decays in this example by Auger electron emission, and the absorption spectroscopy follows the decay of the hole...

  3. Optical absorption spectra of Ag-11 isomers

    DEFF Research Database (Denmark)

    Martinez, Jose Ignacio; Fernandez, E. M.

    2009-01-01

    The optical absorption spectra of the three most; stable structural isomers of the Ag-11 cluster were calculated using the time-dependent, density functional theory within the Casida formalism. The slightly different, spectra, of the isomers may permit the identification of the ground-stale confi......The optical absorption spectra of the three most; stable structural isomers of the Ag-11 cluster were calculated using the time-dependent, density functional theory within the Casida formalism. The slightly different, spectra, of the isomers may permit the identification of the ground...

  4. Absorptive routines and international patent performance

    Directory of Open Access Journals (Sweden)

    Fernando E. García-Muiña

    2017-04-01

    We enrich the treatment of the absorptive capacity phases including the moderating effects between routines associated to the traditional potential-realized absorptive capacities. Taking into account external knowledge search strategies, the deeper external relationships, the better transference and appropriation of specific external knowledge. Nevertheless, when the moderating role of assimilation is included, cooperation agreements appear as the most efficient source of external knowledge. Finally, we show that technological tools let firms store and structure the information making easier its use for international patenting. This positive effect is reinforced in the presence of exploitation routines, since technological knowledge will better fit to the industry's key factors of success.

  5. Absorption of pentacaine from ulcerous rat stomach

    International Nuclear Information System (INIS)

    Tomcikova, O.; Babulova, A.; Durisova, M.; Trnovec, T.; Benes, L.

    1985-01-01

    Pentacaine is a local anaesthetic which exhibited positive effects on healing of model ulcers in the rat stomach. The in situ disappearance of pentacaine from the ulcerous and intact rat stomach was studied. Gastric ulcers were produced by oral administration of phenylbutazone (200 mg/kg) 3.5 h before absorption experiment. Pentacaine exhibited a biexponential decrease from the lumen of the stomach, the rate of which was essentially the same in both groups. The total amount of pentacaine absorbed was small because of extremly low absorption rate. (author)

  6. X-ray absorption spectroscopy of photoionised plasmas at Z

    Science.gov (United States)

    Mancini, R. C.

    2011-06-01

    Photoionised plasmas are found in astrophysical environments such as x-ray binaries, active galactic nuclei, and in the accretion disks of compact objects. The Z facility at Sandia National Laboratories is a powerful source of x-rays that enables us to produce and study in the laboratory photoionised plasmas relevant for astrophysics under well characterized conditions. We discuss an experimental and theory/modeling effort in which the intense x-ray flux emitted at the collapse of a z-pinch experiment conducted at Z is employed to produce a neon photoionized plasma. The broad-band x-ray radiation flux from the z-pinch is used to both create the neon photoionised plasma and provide a source of backlighting photons to study the atomic kinetics through K-shell line absorption spectroscopy. The plasma is contained in a cm-scale gas cell located at about 5 cm from the z-pinch, and the filling pressure is carefully monitored all the way to shot time since it determines the particle number density of the plasma. Time-integrated and gated transmission spectra are recorded with a TREX spectrometer equipped with two elliptically-bent crystals and a set of slits to record up to six spatially-resolved spectra per crystal in the same shot. The spectral resolution is approximately 1000. The transmission data shows line absorption transitions in several ionization stages of neon including Be-, Li-, He- and H-like Ne ions. Detailed modeling calculations of the absorption spectra are used to interpret and model the high-resolution transmission spectra recorded in the Z experiments with the goal of extracting the ion population distribution of the plasma. Furthermore, the analysis of the gated data provides a window into the dynamics of the photoionized plasma. The data analysis is performed with the aid of a novel application of genetic algorithms to plasma spectroscopy.

  7. UV Absorption Measurements of Nitric Oxide Compared to Probe Sampling Data for Measurements in a Turbine Engine Exhaust at Simulated Altitude Conditions

    National Research Council Canada - National Science Library

    Howard, R

    1997-01-01

    .... NO-UV absorption measurements, using both resonance and continuum lamps, were made through several chords of the exhaust flow near the nozzle exit plane as a part of a larger effort to characterize...

  8. Colony collapse disorder: a descriptive study.

    Directory of Open Access Journals (Sweden)

    Dennis Vanengelsdorp

    Full Text Available BACKGROUND: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L. colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD. METHODS AND PRINCIPAL FINDINGS: Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels, no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor were higher in control colonies than CCD-affected colonies. CONCLUSIONS/SIGNIFICANCE: This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted.

  9. Colony collapse disorder: a descriptive study.

    Science.gov (United States)

    Vanengelsdorp, Dennis; Evans, Jay D; Saegerman, Claude; Mullin, Chris; Haubruge, Eric; Nguyen, Bach Kim; Frazier, Maryann; Frazier, Jim; Cox-Foster, Diana; Chen, Yanping; Underwood, Robyn; Tarpy, David R; Pettis, Jeffery S

    2009-08-03

    Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L.) colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD) because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD. Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor) were higher in control colonies than CCD-affected colonies. This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted.

  10. Ultrafast transient absorption revisited: Phase-flips, spectral fingers, and other dynamical features

    Energy Technology Data Exchange (ETDEWEB)

    Cina, Jeffrey A., E-mail: cina@uoregon.edu; Kovac, Philip A. [Department of Chemistry and Biochemistry, and Oregon Center for Optical, Molecular, and Quantum Science, University of Oregon, Eugene, Oregon 97403 (United States); Jumper, Chanelle C. [Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6 (Canada); Dean, Jacob C.; Scholes, Gregory D., E-mail: gscholes@princeton.edu [Department of Chemistry, Princeton University, Princeton, New Jersey 08544 (United States)

    2016-05-07

    We rebuild the theory of ultrafast transient-absorption/transmission spectroscopy starting from the optical response of an individual molecule to incident femtosecond pump and probe pulses. The resulting description makes use of pulse propagators and free molecular evolution operators to arrive at compact expressions for the several contributions to a transient-absorption signal. In this alternative description, which is physically equivalent to the conventional response-function formalism, these signal contributions are conveniently expressed as quantum mechanical overlaps between nuclear wave packets that have undergone different sequences of pulse-driven optical transitions and time-evolution on different electronic potential-energy surfaces. Using this setup in application to a simple, multimode model of the light-harvesting chromophores of PC577, we develop wave-packet pictures of certain generic features of ultrafast transient-absorption signals related to the probed-frequency dependence of vibrational quantum beats. These include a Stokes-shifting node at the time-evolving peak emission frequency, antiphasing between vibrational oscillations on opposite sides (i.e., to the red or blue) of this node, and spectral fingering due to vibrational overtones and combinations. Our calculations make a vibrationally abrupt approximation for the incident pump and probe pulses, but properly account for temporal pulse overlap and signal turn-on, rather than neglecting pulse overlap or assuming delta-function excitations, as are sometimes done.

  11. Photothermal Determination of Absorption and Scattering Spectra of Silver Nanoparticles.

    Science.gov (United States)

    Marcano Olaizola, Aristides

    2018-02-01

    This work reports on photothermal lens spectra of silver nanoparticles of different dimensions in the spectral region of 370-730 nm performed using an arc-lamp-based photothermal spectrophotometer. We show that the photothermal and extinction cross-section spectra of the samples are similar for nanoparticles of reduced dimensions where scattering effects are small. The results differ substantially for nanoparticles of a diameter larger than 30 nm for which scattering becomes relevant. We demonstrate that the photothermal spectrum corresponds to the absorption component of the particle's extinction. Photothermal spectra show a clear picture of the plasmonic peaks of the nanoparticle even in the presence of high scattering. By subtracting the photothermal component from the total extinction, we extract the scattering cross-section spectra of the nanoparticles. The technique allows determination of the absorption and scattering components of the extinction providing a better understanding of the particle's optical properties. The results agree well with the Mie approximation, which is valid for a single spherical nanoparticle. We discuss and demonstrate the application of the method to characterize particles of arbitrary shape and dimensions.

  12. Tunneling times in bianisotropic, dispersive and absorptive metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Radosavljević, Sanja [School of Electrical Engineering, University of Belgrade, Bulevar kralja Aleksandra 73, 11120 Belgrade (Serbia); Photonics Research Group, Ghent University – imec, Sint-Pietersnieuwstraat 41, 9000 Ghent (Belgium); Radovanović, Jelena, E-mail: radovanovic@etf.bg.ac.rs [School of Electrical Engineering, University of Belgrade, Bulevar kralja Aleksandra 73, 11120 Belgrade (Serbia); Milanović, Vitomir [School of Electrical Engineering, University of Belgrade, Bulevar kralja Aleksandra 73, 11120 Belgrade (Serbia)

    2016-12-09

    Tunneling times in complex bianisotropic materials have been examined in detail, with absorption and dispersion taken into account. Tunneling is characterized by the dwell and the phase tunneling time. In this paper, we have developed a theoretical model and derived the appropriate expressions for each of these quantities, as well as a relationship between them and the corresponding expression for the energy density. The model has been verified through numerical calculations based on experimental data. We have distinguished cases in which the phases of transmitted and incident wave match each other, and showed that for small angles of incidence, the time that the wave spends inside the barrier can be approximated as a linear function of the barrier width. The Hartman effect has been detected, although for very thick layers of metamaterial. - Highlights: • We analyze the tunneling times in bianisotropic, dispersive and absorptive metamaterials. • Conditions of zero phase tunneling time are identified for a range of frequencies of interest. • The Hartman effect has been detected for very thick barriers of metamaterial.

  13. Cyclic Organic Peroxides Characterization by Mass Spectrometry and Raman Microscopy

    Science.gov (United States)

    2011-04-01

    included d -ace- tone (99% isotope), acetone, cyclopentanone, hexamethylene tetraamine, benzoyl peroxide (98% w/w), and formaldehyde (CH O, 37% wt...absorption of the N-H stretching at 3336 cm in FTIR absorption and 3346 cm in Raman scattering [40], [41]. Urea has a strong carbonyl absorption in the range...demonstrate the presence of a carbonyl group. The corresponding Raman signal was observed about 1650–1770 cm . Characterization of the nitrogen-carbon bond

  14. Water absorption characteristic of interlocking compressed earth brick units

    Science.gov (United States)

    Bakar, B. H. Abu; Saari, S.; Surip, N. A.

    2017-10-01

    This study aims to investigate the water absorption characteristic of interlocking compressed earth brick (ICEB) units. Apart from compressive strength, water absorption is an important property in masonry. This property can affect the quality of the brick itself and the bond strength between the brick and mortar in masonry structures and can result in reducing its strength properties. The units were tested for 24 h water absorption and 5 h boiling water absorption. A total of 170 ICEB units from four ICEB types underwent both tests. For the 24 h water absorption, the ICEB units were dried in the oven for 24 h and then cooled before being weighed. Thereafter, each brick was immersed in water for 24 h and weighed. The same specimens used for the 24 h water absorption test were re-used for the 5 h boiling water absorption test. After completing the 24 h water absorption test, the brick was boiled for 5-hours and weighed. The highest water absorption for the ICEBs in the 24-hour water absorption and 5 h boiling water absorption tests are 15.09% and 17.18%, respectively. The half brick has the highest water absorption (15.87%), whereas the beam brick has the lowest (13.20%). The water absorption of an ICEB unit is higher than that of normal bricks, although the water absorption of the former remains below the maximum rate of the brick water absorption (21%).

  15. The effect of refractive index changes in an intracavity absorption on the laser output power

    International Nuclear Information System (INIS)

    Al-Hawat, Sh.; Eskef, M.

    2007-10-01

    A model describing the intra-cavity absorption has been developed. The model allows for a reliable description of the attenuation of laser power as a function of the gas pressure inside the absorption cell, conducting both real and imaginary parts of the refractive index of the absorbing gas. The model relies on an adequate integration of the additional loss due to the absorption into the rate equations. After that the rate equations are solved under steady state conditions, which is quite reliable for a cw CO 2 laser. The oscillation, clearly observed in case of weak absorption, is described in the framework of an interference model considering the electric field inside the cavity as the interference result of successive phase correlated waves differing from each other in the number of passes made through the cavity. The phase shift is determined by the optical length of the cavity depending on the real part of the refractive index of the gas in the absorption cell. The model has been applied to analyze a large set of attenuation curves obtained in a previous work, in which intra-cavity absorption was measured for the three gases CFC-11, 12, 22 using a tunable cw CO 2 laser at 44 lines of the emission spectrum of the CO 2 molecule distributed on the branches P and R of the two bands at 9.6 μm and 10.6 μm. For mostly all examples, the value of the absorption cross section (imaginary part of the refractive index) has been determined by fitting the model to the experimental data. Furthermore, the value of the linear polarizability (real part of the refractive index) has been calculated from the oscillation period for all examples, in which the attenuation curve exhibits reliable oscillating behavior. The results are in fair agreement with the values of the absorption cross section published in the Hitran data base, as well as with the results obtained from independent absorption measurements performed outside the cavity (Author)

  16. Role of regional absorption and gastrointestinal motility on variability in oral absorption of a model drug.

    Science.gov (United States)

    Narang, Ajit S; Balakrishnan, Anand; Morrison, John; Li, Jinjiang; Wang, Jennifer; Gu, Huidong; Taylor, Katrina; Santone, Kenneth; Ehrmann, Jon; Beyer, Sophie; Lu, Xujin; Ketner, Rod; Pizzano, Jennifer; Orcutt, Tami; Shields, Eric; Dulac, Heidi; Aborn, Sharon; Batchelder, Margaret; Lentz, Kimberley

    2017-08-01

    Variability in oral absorption in pre-clinical species makes human dose projection challenging. In this study, we investigated the mechanistic basis of variability in oral absorption of a model hydrophobic compound with pH-dependent solubility, BMS-955829, after oral dosing in rats, dogs, and cynomolgus monkeys. The contribution of regional absorption to pharmacokinetic variability was assessed in ported monkeys by direct intraduodenal and intraileal administration. The effect of BMS-955829 on gastric emptying and intestinal motility was investigated by radiography after co-administration of barium. BMS-955829 exhibited species dependent oral bioavailability, with high variability in monkeys. During regional absorption studies, highest rate of drug absorption was observed after direct intraduodenal administration. Radiography studies indicated that BMS-955829 slowed gastric emptying and intestinal motility. The effect of rate and site of drug release on oral exposure was studied using different drug product formulations. Reducing the rate of drug release reduced oral exposure variability without compromising exposure in cynomolgus monkeys. This effect was likely mediated by avoidance of rapid initial absorption and drug effect on gastric emptying and intestinal transit within the biorelevant timeframe. Thus, drug release rate can modulate the effect of physiological factors on variability in the oral absorption of sensitive compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Examination of the Measurement of Absorption Using the Reverberant Room Method for Highly Absorptive Acoustic Foam

    Science.gov (United States)

    Hughes, William O.; McNelis, Anne M.; Chris Nottoli; Eric Wolfram

    2015-01-01

    The absorption coefficient for material specimens are needed to quantify the expected acoustic performance of that material in its actual usage and environment. The ASTM C423-09a standard, "Standard Test Method for Sound Absorption and Sound Absorption Coefficients by the Reverberant Room Method" is often used to measure the absorption coefficient of material test specimens. This method has its basics in the Sabine formula. Although widely used, the interpretation of these measurements are a topic of interest. For example, in certain cases the measured Sabine absorption coefficients are greater than 1.0 for highly absorptive materials. This is often attributed to the diffraction edge effect phenomenon. An investigative test program to measure the absorption properties of highly absorbent melamine foam has been performed at the Riverbank Acoustical Laboratories. This paper will present and discuss the test results relating to the effect of the test materials' surface area, thickness and edge sealing conditions. A follow-on paper is envisioned that will present and discuss the results relating to the spacing between multiple piece specimens, and the mounting condition of the test specimen.

  18. The Absorption Refrigerator as a Thermal Transformer

    Science.gov (United States)

    Herrmann, F.

    2009-01-01

    The absorption refrigerator can be considered a thermal transformer, that is, a device that is analogous to the electric transformer. The analogy is based on the correspondence between the extensive quantities, entropy and electric charge and the intensive variables, temperature and electric potential. (Contains 1 footnote and 6 figures.)

  19. Acoustic absorption of geopolymer/sand mixture

    Czech Academy of Sciences Publication Activity Database

    Perná, Ivana; Hanzlíček, Tomáš; Straka, Pavel; Steinerová, Michaela

    2009-01-01

    Roč. 53, č. 1 (2009), s. 48-51 ISSN 0862-5468 Institutional research plan: CEZ:AV0Z30460519 Keywords : acoustic absorption coefficient * geopolymer Subject RIV: JI - Composite Materials Impact factor: 0.649, year: 2009 www.ceramics-silikaty.cz/2009/pdf/2009_01_48.pdf

  20. A method optimization study for atomic absorption ...

    African Journals Online (AJOL)

    Sadia Ata

    2014-04-24

    Apr 24, 2014 ... The atomic absorption spectrophotometer (Hitachi model. A-1800) was used during this study. For simultaneous analysis, it consists of eight turret lamps with a wavelength range of. 190–900 nm. For analysis precision, it has D2 and self reversal background correction with a grating of 1800 gooves/mm.